Sati, Hisham
2011-06-01
M-theory can be defined on closed manifolds as well as on manifolds with boundary. As an extension, we show that manifolds with corners appear naturally in M-theory. We illustrate this with four situations: the lift to bounding 12 dimensions of M-theory on anti-de Sitter spaces, ten-dimensional heterotic string theory in relation to 12 dimensions, and the two M-branes within M-theory in the presence of a boundary. The M2-brane is taken with (or as) a boundary and the worldvolume of the M5-brane is viewed as a tubular neighborhood. We then concentrate on the (variant) of the heterotic theory as a corner and explore analytical and geometric consequences. In particular, we formulate and study the phase of the partition function in this setting and identify the corrections due to the corner(s). The analysis involves considering M-theory on disconnected manifolds and makes use of the extension of the Atiyah-Patodi-Singer index theorem to manifolds with corners and the b-calculus of Melrose.
International Nuclear Information System (INIS)
Sati, Hisham
2011-01-01
M-theory can be defined on closed manifolds as well as on manifolds with boundary. As an extension, we show that manifolds with corners appear naturally in M-theory. We illustrate this with four situations: the lift to bounding 12 dimensions of M-theory on anti-de Sitter spaces, ten-dimensional heterotic string theory in relation to 12 dimensions, and the two M-branes within M-theory in the presence of a boundary. The M2-brane is taken with (or as) a boundary and the worldvolume of the M5-brane is viewed as a tubular neighborhood. We then concentrate on the (variant) of the heterotic theory as a corner and explore analytical and geometric consequences. In particular, we formulate and study the phase of the partition function in this setting and identify the corrections due to the corner(s). The analysis involves considering M-theory on disconnected manifolds and makes use of the extension of the Atiyah-Patodi-Singer index theorem to manifolds with corners and the b-calculus of Melrose.
Schwarz, John H.
1995-01-01
A proposed duality between type IIB superstring theory on R^9 X S^1 and a conjectured 11D fundamental theory (``M theory'') on R^9 X T^2 is investigated. Simple heuristic reasoning leads to a consistent picture relating the various p-branes and their tensions in each theory. Identifying the M theory on R^{10} X S^1 with type IIA superstring theory on R^{10}, in a similar fashion, leads to various relations among the p-branes of the IIA theory.
International Nuclear Information System (INIS)
Paulot, Louis
2003-01-01
In their search for a unified theory of fundamental interactions, with quantum gravity, physicists introduced superstring theories. In addition to the fundamental strings, they contain extended objects of diverse dimensions, exchanged by U-duality groups. There is also a conjectured mother theory, called 'M-theory', which would give eleven-dimensional supergravity in the low energy limit. In this work, we show that one can construct from del Pezzo surfaces generalized Kac-Moody super-algebras which extend U-duality groups. These super-algebras give the bosonic fields content of M-theory dimensional reductions. We recover the fields equations of motion as a self-duality condition, related to a symmetry of the Picard lattice of the corresponding del Pezzo surface. This allows to explain the symmetry of the 'magic triangle' of Cremmer, Julia, Lue and Pope. (author) [fr
International Nuclear Information System (INIS)
Ooguri, H.; Lawrence Berkeley National Lab., CA
1997-09-01
A low energy effective theory of parallel D(irichlet) branes is a gauge theory with sixteen supercharges, but one can consider a web of brane to realize situations with reduced number of supersymmetry. In this talk, the authors discusses four-dimensional theories with N = 1 and 2 supersymmetry (i.e. four and eight supercharges). In the case of theories with N = 2 supersymmetry, the exact description of the Coulomb branch is given by reinterpreting the web of branes as a configuration of a single fivebrane in the IIA theory. Recently the authors studied the case with N = 1 supersymmetry, and found that description in terms of the fivebrane in M Theory captures strong coupling dynamics of the N = 1 gauge theory in four dimensions. In particular, they found that the configuration of the fivebrane geometrically encodes information on the Affleck-Dine-Seiberg superpotential and the structure of the quantum moduli space of vacua
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Schwarz, J. H.
1998-01-01
BPS saturated p-branes play an important role in recent progress in understanding superstring theory and M theory. One approach to understanding the dynamics of p-branes is to formulate an effective (p+1) dimensional world-volume theory. The construction of such brane actions involves a number of interesting issues. One such issue is how to formulate the action for theories that contain chiral bosons. The two main examples, which are the M theory five-brane and the heterotic string, are described in this lecture. Also, double dimensional reduction of the M theory five-brane on K3 is shown to give the heterotic string. (Author). 32 refs
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Becker, Katrin; Becker, Melanie; Robbins, Daniel
2015-01-01
In this talk we report on recent progress in describing compactifications of string theory and M-theory on G 2 and Spin(7) manifolds. We include the infinite set of α’-corrections and describe the entire tower of massless and massive Kaluza–Klein modes resulting from such compactifications. (invited comment)
Sasakian manifolds and M-theory
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Figueroa-O’Farrill, José; Santi, Andrea
2016-01-01
We extend the link between Einstein Sasakian manifolds and Killing spinors to a class of η-Einstein Sasakian manifolds, both in Riemannian and Lorentzian settings, characterizing them in terms of generalized Killing spinors. We propose a definition of supersymmetric M-theory backgrounds on such a geometry and find a new class of such backgrounds, extending previous work of Haupt, Lukas and Stelle. (paper)
Topological M Theory from Pure Spinor Formalism
Grassi, P A; Grassi, Pietro Antonio; Vanhove, Pierre
2005-01-01
We construct multiloop superparticle amplitudes in 11d using the pure spinor formalism. We explain how this construction reduces to the superparticle limit of the multiloop pure spinor superstring amplitudes prescription. We then argue that this construction points to some evidence for the existence of a topological M theory based on a relation between the ghost number of the full-fledged supersymmetric critical models and the dimension of the spacetime for topological models. In particular, we show that the extensions at higher orders of the previous results for the tree and one-loop level expansion for the superparticle in 11 dimensions is related to a topological model in 7 dimensions.
The chiral anomaly from M theory
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Guersoy, Umut; Hartnoll, Sean A.; Portugues, Ruben
2004-01-01
We argue that the chiral anomaly of N=1 super Yang-Mills theory admits a dual description as spontaneous symmetry breaking in M theory on G 2 holonomy manifolds. We identify an angle of the G 2 background dual to the anomalous U(1) R current in field theory. This angle is not an isometry of the metric and we therefore develop a theory of 'massive isometry' to describe fluctuations about such angles. Another example of a massive isometry occurs in the Atiyah-Hitchin metric
Neutrino mass from M theory SO(10)
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Acharya, Bobby S.; Bożek, Krzysztof; Romão, Miguel Crispim; King, Stephen F.; Pongkitivanichkul, Chakrit
2016-01-01
We study the origin of neutrino mass from SO(10) arising from M Theory compactified on a G_2-manifold. This is linked to the problem of the breaking of the extra U(1) gauge group, in the SU(5)×U(1) subgroup of SO(10), which we show can achieved via a (generalised) Kolda-Martin mechanism. The resulting neutrino masses arise from a combination of the seesaw mechanism and induced R-parity breaking contributions. The rather complicated neutrino mass matrix is analysed for one neutrino family and it is shown how phenomenologically acceptable neutrino masses can emerge.
Neutrino mass from M theory SO(10)
Energy Technology Data Exchange (ETDEWEB)
Acharya, Bobby S. [Department of Physics, King’s College,WC2R 2LS, London (United Kingdom); International Centre for Theoretical Physics,I-34151 Trieste (Italy); Bożek, Krzysztof [Department of Physics, King’s College,WC2R 2LS, London (United Kingdom); Romão, Miguel Crispim; King, Stephen F. [School of Physics and Astronomy, University of Southampton,SO17 1BJ, Southampton (United Kingdom); Pongkitivanichkul, Chakrit [Department of Physics, King’s College,WC2R 2LS, London (United Kingdom)
2016-11-29
We study the origin of neutrino mass from SO(10) arising from M Theory compactified on a G{sub 2}-manifold. This is linked to the problem of the breaking of the extra U(1) gauge group, in the SU(5)×U(1) subgroup of SO(10), which we show can achieved via a (generalised) Kolda-Martin mechanism. The resulting neutrino masses arise from a combination of the seesaw mechanism and induced R-parity breaking contributions. The rather complicated neutrino mass matrix is analysed for one neutrino family and it is shown how phenomenologically acceptable neutrino masses can emerge.
Multiple Membranes in M-theory
Bagger, Jonathan; Mukhi, Sunil; Papageorgakis, Constantinos
2013-01-01
We review developments in the theory of multiple, parallel membranes in M-theory. After discussing the inherent difficulties pertaining to a maximally supersymmetric lagrangian formulation with the appropriate field content and symmetries, we discuss how introducing the concept of 3-algebras allows for such a description. Different choices of 3-algebras lead to distinct classes of 2+1 dimensional theories with varying degrees of supersymmetry. We then describe how these are equivalent to a type of conventional superconformal Chern-Simons gauge theories at level k, coupled to bifundamental matter. Analysing the physical properties of these theories leads to the identification of a certain subclass of models with configurations of M2-branes in Z_k orbifolds of M-theory. In addition these models give rise to a whole new sector of the gauge/gravity duality in the form of an AdS_4/CFT_3 correspondence. We also discuss mass deformations, higher derivative corrections as well as the possibility of extracting informa...
Gauged supergravities from M-theory reductions
Katmadas, Stefanos; Tomasiello, Alessandro
2018-04-01
In supergravity compactifications, there is in general no clear prescription on how to select a finite-dimensional family of metrics on the internal space, and a family of forms on which to expand the various potentials, such that the lower-dimensional effective theory is supersymmetric. We propose a finite-dimensional family of deformations for regular Sasaki-Einstein seven-manifolds M 7, relevant for M-theory compactifications down to four dimensions. It consists of integrable Cauchy-Riemann structures, corresponding to complex deformations of the Calabi-Yau cone M 8 over M 7. The non-harmonic forms we propose are the ones contained in one of the Kohn-Rossi cohomology groups, which is finite-dimensional and naturally controls the deformations of Cauchy-Riemann structures. The same family of deformations can be also described in terms of twisted cohomology of the base M 6, or in terms of Milnor cycles arising in deformations of M 8. Using existing results on SU(3) structure compactifications, we briefly discuss the reduction of M-theory on our class of deformed Sasaki-Einstein manifolds to four-dimensional gauged supergravity.
Becker, Katrin; Becker, Melanie; Schwarz, John H.
String theory is one of the most exciting and challenging areas of modern theoretical physics. This book guides the reader from the basics of string theory to recent developments. It introduces the basics of perturbative string theory, world-sheet supersymmetry, space-time supersymmetry, conformal field theory and the heterotic string, before describing modern developments, including D-branes, string dualities and M-theory. It then covers string geometry and flux compactifications, applications to cosmology and particle physics, black holes in string theory and M-theory, and the microscopic origin of black-hole entropy. It concludes with Matrix theory, the AdS/CFT duality and its generalizations. This book is ideal for graduate students and researchers in modern string theory, and will make an excellent textbook for a one-year course on string theory. It contains over 120 exercises with solutions, and over 200 homework problems with solutions available on a password protected website for lecturers at www.cambridge.org/9780521860697. Comprehensive coverage of topics from basics of string theory to recent developments Ideal textbook for a one-year course in string theory Includes over 100 exercises with solutions Contains over 200 homework problems with solutions available to lecturers on-line
Multiple membranes in M-theory
Energy Technology Data Exchange (ETDEWEB)
Bagger, Jonathan, E-mail: bagger@jhu.edu [Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States); Lambert, Neil, E-mail: neil.lambert@cern.ch [Theory Division, CERN, 1211 Geneva 23 (Switzerland); Department of Mathematics, King’s College London, London WC2R 2LS (United Kingdom); Isaac Newton Institute for Mathematical Sciences, 20 Clarkson Road, Cambridge, CB3 OEH (United Kingdom); Mukhi, Sunil, E-mail: mukhi@tifr.res.in [Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400 005 (India); Isaac Newton Institute for Mathematical Sciences, 20 Clarkson Road, Cambridge, CB3 OEH (United Kingdom); Papageorgakis, Constantinos, E-mail: papageorgakis@physics.rutgers.edu [NHETC and Department of Physics and Astronomy, Rutgers University, 126 Frelinghuysen Road, Piscataway, NJ 08854-8019 (United States); Isaac Newton Institute for Mathematical Sciences, 20 Clarkson Road, Cambridge, CB3 OEH (United Kingdom)
2013-06-01
We review developments in the theory of multiple, parallel membranes in M-theory. After discussing the inherent difficulties with constructing a maximally supersymmetric lagrangian with the appropriate field content and symmetries, we introduce 3-algebras and show how they allow for such a description. Different choices of 3-algebras lead to distinct classes of 2+1 dimensional theories with varying degrees of supersymmetry. We then demonstrate that these theories are equivalent to conventional superconformal Chern–Simons gauge theories at level k, but with bifundamental matter. Analysing the physical properties of these theories leads to the identification of a certain subclass of models with configurations of M2-branes on Z{sub k} orbifolds. These models give rise to a whole new gauge/gravity duality in the form of an AdS{sub 4}/CFT{sub 3} correspondence. We also discuss mass deformations, higher derivative corrections, and the possibility of extracting information about M5-brane physics.
Multiple membranes in M-theory
International Nuclear Information System (INIS)
Bagger, Jonathan; Lambert, Neil; Mukhi, Sunil; Papageorgakis, Constantinos
2013-01-01
We review developments in the theory of multiple, parallel membranes in M-theory. After discussing the inherent difficulties with constructing a maximally supersymmetric lagrangian with the appropriate field content and symmetries, we introduce 3-algebras and show how they allow for such a description. Different choices of 3-algebras lead to distinct classes of 2+1 dimensional theories with varying degrees of supersymmetry. We then demonstrate that these theories are equivalent to conventional superconformal Chern–Simons gauge theories at level k, but with bifundamental matter. Analysing the physical properties of these theories leads to the identification of a certain subclass of models with configurations of M2-branes on Z k orbifolds. These models give rise to a whole new gauge/gravity duality in the form of an AdS 4 /CFT 3 correspondence. We also discuss mass deformations, higher derivative corrections, and the possibility of extracting information about M5-brane physics
From chaos to unification: U theory vs. M theory
International Nuclear Information System (INIS)
Ye, Fred Y.
2009-01-01
A unified physical theory called U theory, that is different from M theory, is defined and characterized. U theory, which includes spinor and twistor theory, loop quantum gravity, causal dynamical triangulations, E-infinity unification theory, and Clifford-Finslerian unifications, is based on physical tradition and experimental foundations. In contrast, M theory pays more attention to mathematical forms. While M theory is characterized by supersymmetry string theory, U theory is characterized by non-supersymmetry unified field theory.
A Note on Tensionless Strings in M-Theory
Davis, K.
1996-01-01
In this article we examine the appearance of tensionless strings in M-Theory. We subsequently interpret these tensionless strings in a String Theory context. In particular, we examine tensionless strings appearing in M-Theory on $S^{1}$, M-Theory on $S^{1} / {\\bf Z}_{2}$, and M-Theory on $T^{2}$; we then interpret the appearance of such strings in a String Theory context. Then we reverse this process and examine the appearance of some tensionless strings in String Theory. Subsequently we inte...
N=1 field theory duality from M theory
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Schmaltz, M.; Sundrum, R.
1998-01-01
We investigate Seiberg close-quote s N=1 field theory duality for four-dimensional supersymmetric QCD with the M-theory 5-brane. We find that the M-theory configuration for the magnetic dual theory arises via a smooth deformation of the M-theory configuration for the electric theory. The creation of Dirichlet 4-branes as Neveu-Schwarz 5-branes are passed through each other in type IIA string theory is given an elegant derivation from M theory. copyright 1998 The American Physical Society
M-Theory and Maximally Supersymmetric Gauge Theories
Lambert, Neil
2012-01-01
In this informal review for non-specalists we discuss the construction of maximally supersymmetric gauge theories that arise on the worldvolumes branes in String Theory and M-Theory. Particular focus is made on the relatively recent construction of M2-brane worldvolume theories. In a formal sense, the existence of these quantum field theories can be viewed as predictions of M-Theory. Their construction is therefore a reinforcement of the ideas underlying String Theory and M-Theory. We also briefly discuss the six-dimensional conformal field theory that is expected to arise on M5-branes. The construction of this theory is not only an important open problem for M-Theory but also a significant challenge to our current understanding of quantum field theory more generally.
M theory and singularities of exceptional holonomy manifolds
International Nuclear Information System (INIS)
Acharya, Bobby S.; Gukov, Sergei
2004-12-01
M theory compactifications on G 2 holonomy manifolds, whilst supersymmetric, require singularities in order to obtain non-Abelian gauge groups, chiral fermions and other properties necessary for a realistic model of particle physics. We review recent progress in understanding the physics of such singularities. Our main aim is to describe the techniques which have been used to develop our understanding of M theory physics near these singularities. In parallel, we also describe similar sorts of singularities in Spin(7) holonomy manifolds which correspond to the properties of three dimensional field theories. As an application, we review how various aspects of strongly coupled gauge theories, such as confinement, mass gap and non-perturbative phase transitions may be given a simple explanation in M theory. (author)
M Theory, G2-manifolds and four dimensional physics
International Nuclear Information System (INIS)
Acharya, B.S.
2003-01-01
M theory on a manifold of G 2 -holonomy is a natural framework for obtaining vacua with four large spacetime dimensions and N = 1 supersymmetry. In order to obtain, within this framework, the standard features of particle physics, namely non-Abelian gauge groups and chiral fermions, we consider G 2 -manifolds with certain kinds of singularities at which these features reside. The aim of these lectures is to describe in detail how the above picture emerges. Along the way we will see how interesting aspects of strongly coupled gauge theories, such as confinement, receive relatively simple explanations within the context of M theory. (author)
Cosmological singularities in string and M-theory cosmology
Vazquez-Mozo, M.A.; Ibanez, J.
2000-01-01
I discuss the point of view that non-renormalizability in General Relativity is a consequence of dealing with a low-energy effective field theory of the gravitational field, and how Einstein-Brans-Dicke gravity is retrieved from string/M-theory at low energies. After examining the role of stringy
Dualities in M-theory and Born-Infeld Theory
International Nuclear Information System (INIS)
Brace, Daniel M.
2001-01-01
We discuss two examples of duality. The first arises in the context of toroidal compactification of the discrete light cone quantization of M-theory. In the presence of nontrivial moduli coming from the M-theory three form, it has been conjectured that the system is described by supersymmetric Yang-Mills gauge theory on a noncommutative torus. We are able to provide evidence for this conjecture, by showing that the dualities of this M-theory compactification, which correspond to T-duality in Type IIA string theory, are also dualities of the noncommutative supersymmetric Yang-Mills description. One can also consider this as evidence for the accuracy of the Matrix Theory description of M-theory in this background. The second type of duality is the self-duality of theories with U(1) gauge fields. After discussing the general theory of duality invariance for theories with complex gauge fields, we are able to find a generalization of the well known U(1) Born-Infeld theory that contains any number of gauge fields and which is invariant under the maximal duality group. We then find a supersymmetric extension of our results, and also show that our results can be extended to find Born-Infeld type actions in any even dimensional spacetime
Cavaglia, Marco
2001-01-01
We discuss a simple cosmological model derived from M-theory. Three assumptions lead naturally to a pre-big bang scenario: (a) 11-dimensional supergravity describes the low-energy world; (b) non-gravitational fields live on a three-dimensional brane; and (c) asymptotically past triviality.
Probing non-perturbative effects in M-theory
International Nuclear Information System (INIS)
Hatsuda, Yasuyuki; Okuyama, Kazumi
2014-07-01
The AdS/CFT correspondence enables us to probe M-theory on various backgrounds from the corresponding dual gauge theories. Here we investigate in detail a three-dimensional U(N) N=4 super Yang-Mills theory coupled to one adjoint hypermultiplet and N f fundamental hypermultiplets, which is large N dual to M-theory on AdS 4 x S 7 /Z N f . Using the localization and the Fermi-gas formulation, we explore non-perturbative corrections to the partition function. As in the ABJM theory, we find that there exists a non-trivial pole cancellation mechanism, which guarantees the theory to be well-defined, between worldsheet instantons and membrane instantons for all rational (in particular, physical or integral) values of N f .
M-Theory Model-Building and Proton Stability
Ellis, Jonathan Richard; Nanopoulos, Dimitri V; Ellis, John; Faraggi, Alon E.
1998-01-01
We study the problem of baryon stability in M theory, starting from realistic four-dimensional string models constructed using the free-fermion formulation of the weakly-coupled heterotic string. Suitable variants of these models manifest an enhanced custodial gauge symmetry that forbids to all orders the appearance of dangerous dimension-five baryon-decay operators. We exhibit the underlying geometric (bosonic) interpretation of these models, which have a $Z_2 \\times Z_2$ orbifold structure similar, but not identical, to the class of Calabi-Yau threefold compactifications of M and F theory investigated by Voisin and Borcea. A related generalization of their work may provide a solution to the problem of proton stability in M theory.
M-theory model-building and proton stability
International Nuclear Information System (INIS)
Ellis, J.; Faraggi, A.E.; Nanopoulos, D.V.; Houston Advanced Research Center, The Woodlands, TX; Academy of Athens
1997-09-01
The authors study the problem of baryon stability in M theory, starting from realistic four-dimensional string models constructed using the free-fermion formulation of the weakly-coupled heterotic string. Suitable variants of these models manifest an enhanced custodial gauge symmetry that forbids to all orders the appearance of dangerous dimension-five baryon-decay operators. The authors exhibit the underlying geometric (bosonic) interpretation of these models, which have a Z 2 x Z 2 orbifold structure similar, but not identical, to the class of Calabi-Yau threefold compactifications of M and F theory investigated by Voisin and Borcea. A related generalization of their work may provide a solution to the problem of proton stability in M theory
Calibrated geometries and non perturbative superpotentials in M-theory
International Nuclear Information System (INIS)
Hernandez, R.
1999-12-01
We consider non perturbative effects in M-theory compactifications on a seven-manifold of G 2 holonomy arising from membranes wrapped on supersymmetric three-cycles. When membranes are wrapped on associative submanifolds they induce a superpotential that can be calculated using calibrated geometry. This superpotential is also derived from compactification on a seven-manifold, to four dimensional Anti-de Sitter spacetime, of eleven dimensional supergravity with non vanishing expectation value of the four-form field strength. (author)
Conformal tension in string theories and M-theory
International Nuclear Information System (INIS)
Barros, Manuel; Ferrandez, Angel; Lucas, Pascual
2000-01-01
This paper deals with string theories and M-theories on backgrounds of the form AdSxM,M being a compact principal U(1)-bundle. These configurations are the natural settings to study Hopf T-dualities (Duff et al., Nucl. Phys. B 544 (1999) 145), and so to define duality chains connecting different string theories and M-theories. There is an increasing great interest in studying those properties (physical or geometrical) which are preserved along the duality chains. For example, it is known that Hopf T-dualities preserve the black hole entropies (Duff et al., Nucl. Phys. B 544 (1999) 145). In this paper we consider a two-parameter family of actions which constitutes a natural variation of the conformal total tension action (also known as Willmore-Chen functional in differential geometry). Then, we show that the existence of wide families of solutions (in particular compact solutions) for the corresponding motion equations is preserved along those duality chains. In particular, we exhibit ample classes of Willmore-Chen submanifolds with a reasonable degree of symmetry in a wide variety of conformal string theories and conformal M-theories, that in addition are solutions of a second variational problem known as the area-volume isoperimetric problem. These are good reasons to refer those submanifolds as the best worlds one can find in a conformal universe. The method we use to obtain this invariant under Hopf T-dualities is based on the principle of symmetric criticality. However, it is used in a two-fold sense. First to break symmetry and so to reduce variables. Second to gain rigidity in direct approaches to integrate the Euler-Lagrange equations. The existence of generalized elastic curves is also important in the explicit exhibition of those configurations. The relationship between solutions and elasticae can be regarded as a holographic property
Aspects of Confinement and Screening in M theory
Elitzur, Shmuel; Rabinovici, Eliezer; Elitzur, Shmuel; Pelc, Oskar; Rabinovici, Eliezer
1999-01-01
Confinement and Screening are investigated in SUSY gauge theories, realized by an M5 brane configuration, extending an approach applied previously to N=1 SYM theory, to other models. The electric flux tubes are identified as M2 branes ending on the M5 branes and the conserved charge they carry is identified as a topological property. The group of charges carried by the flux tubes is calculated and the results agree in all cases considered with the field theoretical expectations. In particular, whenever the dynamical matter is expected to screen the confining force, this is reproduced correctly in the M theory realization.
Loop groups, Kaluza-Klein reduction and M-theory
International Nuclear Information System (INIS)
Bergman, Aaron; Varadarajan, Uday
2005-01-01
We show that the data of a principal G-bundle over a principal circle bundle is equivalent to that of a LG-circumflex (def)/= U(1) x LG-bundle over the base of the circle bundle. We apply this to the Kaluza-Klein reduction of M-theory to IIA and show that certain generalized characteristic classes of the loop group bundle encode the Bianchi identities of the antisymmetric tensor fields of IIA supergravity. We further show that the low dimensional characteristic classes of the central extension of the loop group encode the Bianchi identities of massive IIA, thereby adding support to the conjectures given elsewhere
Quantization conditions and functional equations in ABJ(M) theories
International Nuclear Information System (INIS)
Grassi, Alba; Marino, Marcos; Hatsuda, Yasuyuki
2014-12-01
The partition function of ABJ(M) theories on the three-sphere can be regarded as the canonical partition function of an ideal Fermi gas with a non-trivial Hamiltonian. We propose an exact expression for the spectral determinant of this Hamiltonian, which generalizes recent results obtained in the maximally supersymmetric case. As a consequence, we find an exact WKB quantization condition determining the spectrum which is in agreement with numerical results. In addition, we investigate the factorization properties and functional equations for our conjectured spectral determinants. These functional equations relate the spectral determinants of ABJ theories with consecutive ranks of gauge groups but the same Chern-Simons coupling.
Open BPS wall crossing and M-theory
International Nuclear Information System (INIS)
Aganagic, Mina; Yamazaki, Masahito
2010-01-01
Consider the degeneracies of BPS bound states of one D6-brane wrapping Calabi-Yau X with D0-branes and D2-branes. When we include D4-branes wrapping Lagrangian cycles in addition, D2-branes can end on them. These give rise to new bound states in the d=2, N=(2,2) theory of the D4-branes. We call these 'open' BPS states, in contrast to closed BPS states that arise from D-branes without boundaries. Lifting this to M-theory, we show that the generating function is captured by free Fock space spanned by M2-brane particles ending on M5-branes wrapping the Lagrangian. This implies that the open BPS bound states are counted by the square of the open topological string partition function on X, reduced to the corresponding chamber. Our results give new predictions for open BPS invariants and their wall crossing phenomena when we change the open and closed string moduli. We relate our results to the work of Cecotti and Vafa on wall crossing in the two-dimensional N=(2,2) theories. The findings from the crystal melting model for the open BPS invariants proposed recently fit well with the M-theory predictions.
Four-flux and warped heterotic M-theory compactifications
International Nuclear Information System (INIS)
Curio, Gottfried; Krause, Axel
2001-01-01
In the framework of heterotic M-theory compactified on a Calabi-Yau threefold 'times' an interval, the relation between geometry and four-flux is derived beyond first order. Besides the case with general flux which cannot be described by a warped geometry one is naturally led to consider two special types of four-flux in detail. One choice shows how the M-theory relation between warped geometry and flux reproduces the analogous one of the weakly coupled heterotic string with torsion. The other one leads to a quadratic dependence of the Calabi-Yau volume with respect to the orbifold direction which avoids the problem with negative volume of the first order approximation. As in the first order analysis we still find that Newton's constant is bounded from below at just the phenomenologically relevant value. However, the bound does not require an ad hoc truncation of the orbifold-size any longer. Finally we demonstrate explicitly that to leading order in κ 2/3 no Cosmological constant is induced in the four-dimensional low-energy action. This is in accord with what one can expect from supersymmetry
Knot invariants and M-theory: Proofs and derivations
Errasti Díez, Verónica
2018-01-01
We construct two distinct yet related M-theory models that provide suitable frameworks for the study of knot invariants. We then focus on the four-dimensional gauge theory that follows from appropriately compactifying one of these M-theory models. We show that this theory has indeed all required properties to host knots. Our analysis provides a unifying picture of the various recent works that attempt an understanding of knot invariants using techniques of four-dimensional physics. This is a companion paper to K. Dasgupta, V. Errasti Díez, P. Ramadevi, and R. Tatar, Phys. Rev. D 95, 026010 (2017), 10.1103/PhysRevD.95.026010, covering all but Sec. III C. It presents a detailed mathematical derivation of the main results there, as well as additional material. Among the new insights, those related to supersymmetry and the topological twist are highlighted. This paper offers an alternative, complementary formulation of the contents in the first paper, but is self-contained and can be read independently.
Yukawa couplings in SO(10) heterotic M-theory vacua
International Nuclear Information System (INIS)
Faraggi, Alon E.; Garavuso, Richard S.
2003-01-01
We demonstrate the existence of a class of N=1 supersymmetric nonperturbative vacua of Horava-Witten M-theory compactified on a torus fibered Calabi-Yau 3-fold Z with first homotopy group π 1 (Z)=Z 2 , having the following properties: (1) SO(10) grand unification group, (2) net number of three generations of chiral fermions in the observable sector, and (3) potentially viable matter Yukawa couplings. These vacua correspond to semistable holomorphic vector bundles V Z over Z having structure group SU(4) C , and generically contain M5-branes in the bulk space. The nontrivial first homotopy group allows Wilson line breaking of the SO(10) symmetry. Additionally, we propose how the 11-dimensional Horava-Witten M-theory framework may be used to extend the perturbative calculation of the top quark Yukawa coupling in the realistic free-fermionic models to the nonperturbative regime. The basic argument being that the relevant coupling couples twisted-twisted-untwisted states and can be calculated at the level of the Z 2 xZ 2 orbifold without resorting to the full three generation models
Supersymmetric gauge theories with classical groups via M theory fivebrane
International Nuclear Information System (INIS)
Terashima, S.
1998-01-01
We study the moduli space of vacua of four-dimensional N=1 and N=2 supersymmetric gauge theories with the gauge groups Sp(2N c ), SO(2N c ) and SO(2N c +1) using the M theory fivebrane. Higgs branches of the N=2 supersymmetric gauge theories are interpreted in terms of the M theory fivebrane and the type IIA s-rule is realized in it. In particular, we construct the fivebrane configuration which corresponds to a special Higgs branch root. This root is analogous to the baryonic branch root in the SU(N c ) theory which remains as a vacuum after the adjoint mass perturbation to break N=2 to N=1. Furthermore, we obtain the monopole condensations and the meson vacuum expectation values in the confining phase of N=1 supersymmetric gauge theories using the fivebrane technique. These are in complete agreement with the field theory results for the vacua in the phase with a single confined photon. (orig.)
International Nuclear Information System (INIS)
Ketov, S.V.
1997-01-01
Taking the N=2 strings as the starting point, we discuss the equivalent self-dual field theories and analyze their symmetry structure in 2 + 2 dimensions. Restoring the full 'Lorentz' invariance in the target space necessarily leads to an extension of the N=2 string theory to a theory of 2 + 2 dimensional supermembranes propagating in 2 + 10 dimensional target space. The supermembrane requires maximal conformal supersymmetry in 2 + 2 dimensions, in the way advocated by Siegel, and it leads to the self-dual N=4 super-Yang-Mills theory and the self-dual N=8 (gauged) supergravity in 2+2 dimensions. The N=2 strings now appear on equal footing with the other string models as particular limits of the M-theory. (orig.)
Noncommutative Geometry in M-Theory and Conformal Field Theory
Energy Technology Data Exchange (ETDEWEB)
Morariu, Bogdan [Univ. of California, Berkeley, CA (United States)
1999-05-01
In the first part of the thesis I will investigate in the Matrix theory framework, the subgroup of dualities of the Discrete Light Cone Quantization of M-theory compactified on tori, which corresponds to T-duality in the auxiliary Type II string theory. After a review of matrix theory compactification leading to noncommutative supersymmetric Yang-Mills gauge theory, I will present solutions for the fundamental and adjoint sections on a two-dimensional twisted quantum torus and generalize to three-dimensional twisted quantum tori. After showing how M-theory T-duality is realized in supersymmetric Yang-Mills gauge theories on dual noncommutative tori I will relate this to the mathematical concept of Morita equivalence of C*-algebras. As a further generalization, I consider arbitrary Ramond-Ramond backgrounds. I will also discuss the spectrum of the toroidally compactified Matrix theory corresponding to quantized electric fluxes on two and three tori. In the second part of the thesis I will present an application to conformal field theory involving quantum groups, another important example of a noncommutative space. First, I will give an introduction to Poisson-Lie groups and arrive at quantum groups using the Feynman path integral. I will quantize the symplectic leaves of the Poisson-Lie group SU(2)*. In this way we obtain the unitary representations of U_{q}(SU(2)). I discuss the X-structure of SU(2)* and give a detailed description of its leaves using various parametrizations. Then, I will introduce a new reality structure on the Heisenberg double of Fun_{q} (SL(N,C)) for q phase, which can be interpreted as the quantum phase space of a particle on the q-deformed mass-hyperboloid. I also present evidence that the above real form describes zero modes of certain non-compact WZNW-models.
Noncommutative Geometry in M-Theory and Conformal Field Theory
International Nuclear Information System (INIS)
Morariu, Bogdan
1999-01-01
In the first part of the thesis I will investigate in the Matrix theory framework, the subgroup of dualities of the Discrete Light Cone Quantization of M-theory compactified on tori, which corresponds to T-duality in the auxiliary Type II string theory. After a review of matrix theory compactification leading to noncommutative supersymmetric Yang-Mills gauge theory, I will present solutions for the fundamental and adjoint sections on a two-dimensional twisted quantum torus and generalize to three-dimensional twisted quantum tori. After showing how M-theory T-duality is realized in supersymmetric Yang-Mills gauge theories on dual noncommutative tori I will relate this to the mathematical concept of Morita equivalence of C*-algebras. As a further generalization, I consider arbitrary Ramond-Ramond backgrounds. I will also discuss the spectrum of the toroidally compactified Matrix theory corresponding to quantized electric fluxes on two and three tori. In the second part of the thesis I will present an application to conformal field theory involving quantum groups, another important example of a noncommutative space. First, I will give an introduction to Poisson-Lie groups and arrive at quantum groups using the Feynman path integral. I will quantize the symplectic leaves of the Poisson-Lie group SU(2)*. In this way we obtain the unitary representations of U q (SU(2)). I discuss the X-structure of SU(2)* and give a detailed description of its leaves using various parametrizations. Then, I will introduce a new reality structure on the Heisenberg double of Fun q (SL(N,C)) for q phase, which can be interpreted as the quantum phase space of a particle on the q-deformed mass-hyperboloid. I also present evidence that the above real form describes zero modes of certain non-compact WZNW-models
Foliated eight-manifolds for M-theory compactification
Babalic, Elena Mirela; Lazaroiu, Calin Iuliu
2015-01-01
We characterize compact eight-manifolds M which arise as internal spaces in flux compactifications of M-theory down to AdS3 using the theory of foliations, for the case when the internal part ξ of the supersymmetry generator is everywhere non-chiral. We prove that specifying such a supersymmetric background is equivalent with giving a codimension one foliation of M which carries a leafwise G 2 structure, such that the O'Neill-Gray tensors, non-adapted part of the normal connection and the torsion classes of the G 2 structure are given in terms of the supergravity four-form field strength by explicit formulas which we derive. We discuss the topology of such foliations, showing that the C * algebra is a noncommutative torus of dimension given by the irrationality rank of a certain cohomology class constructed from G, which must satisfy the Latour obstruction. We also give a criterion in terms of this class for when such foliations are fibrations over the circle. When the criterion is not satisfied, each leaf of is dense in M.
De Sitter vacua from heterotic M-theory
International Nuclear Information System (INIS)
Becker, Melanie; Curio, Gottfried; Krause, Axel
2004-01-01
It is shown how metastable de Sitter vacua might arise from heterotic M-theory. The balancing of its two non-perturbative effects, open membrane instantons against gaugino condensation on the hidden boundary, which act with opposing forces on the interval length, is used to stabilize the orbifold modulus (dilaton) and other moduli. The non-perturbative effects break supersymmetry spontaneously through F-terms which leads to a positive vacuum energy density. In contrast to the situation for the weakly coupled heterotic string, the charged scalar matter fields receive non-vanishing vacuum expectation values and therefore masses in a phenomenologically relevant regime. It is important that in order to obtain these de Sitter vacua we are not relying on exotic effects or fine-tuning of parameters. Vacua with more realistic supersymmetry breaking scales and gravitino masses are obtained by breaking the hidden E 8 gauge group down to groups of smaller rank. Also small values for the open membrane instanton Pfaffian are favored in this respect. Finally we outline how the incorporation of additional flux superpotentials can be used to stabilize the remaining moduli
M-theory inflation from multi M5-brane dynamics
International Nuclear Information System (INIS)
Becker, Katrin; Becker, Melanie; Krause, Axel
2005-01-01
We derive inflation from M-theory on S 1 /Z 2 via the non-perturbative dynamics of N M5-branes. The open membrane instanton interactions between the M5-branes give rise to exponential potentials which are too steep for inflation individually but lead to inflation when combined together. The resulting type of inflation, known as assisted inflation, facilitates considerably the requirement of having all moduli, except the inflaton, stabilized at the beginning of inflation. During inflation the distances between the M5-branes, which correspond to the inflatons, grow until they reach the size of the S 1 /Z 2 orbifold. At this stage the M5-branes will reheat the universe by dissolving into the boundaries through small instanton transitions. Further flux and non-perturbative contributions become important at this late stage, bringing inflation to an end and stabilizing the moduli. We find that with moderate values for N, one obtains both a sufficient amount of e-foldings and the right size for the spectral index
M theory: a possible unification of physics laws
International Nuclear Information System (INIS)
Fernandes, Alexandre da Silva; Silva, Diego Oliveira Nolasco da; Sousa, Claudio Manoel Gomes de
2011-01-01
Full text: Physics has two pillars which are mutually incompatible: quantum field theory and general relativity theory. Throughout its history, various unifications have been made, and in attempts to have a better understanding of the birth and formation of the Universe is also necessary to unify these pillars. This unification may require 11 dimensions, and 6 of them are compressed so that it cannot be seen with existing instruments. These dimensions are the spaces in which the strings vibrate, and each mode of vibration corresponds to a particle. The last dimension shows that the universe is a brane, it is in full motion in the multiverse and the collision of two branes can answer the biggest problem of cosmology: what was the Big Bang? Black holes can be explained using a theory that contains gravity and quantum mechanics. The theory is still being developed, some problems are being solved and the main one is the experimental problem, because it requires energy levels that are not yet achieved by current particle accelerators. This work presents M theory as a possibility of unification between the micro and macro, which maybe leading us to the theory of everything. (author)
M theory: a possible unification of physics laws
Energy Technology Data Exchange (ETDEWEB)
Fernandes, Alexandre da Silva; Silva, Diego Oliveira Nolasco da; Sousa, Claudio Manoel Gomes de [Universidade Catolica de Brasilia (UCB), DF (Brazil)
2011-07-01
Full text: Physics has two pillars which are mutually incompatible: quantum field theory and general relativity theory. Throughout its history, various unifications have been made, and in attempts to have a better understanding of the birth and formation of the Universe is also necessary to unify these pillars. This unification may require 11 dimensions, and 6 of them are compressed so that it cannot be seen with existing instruments. These dimensions are the spaces in which the strings vibrate, and each mode of vibration corresponds to a particle. The last dimension shows that the universe is a brane, it is in full motion in the multiverse and the collision of two branes can answer the biggest problem of cosmology: what was the Big Bang? Black holes can be explained using a theory that contains gravity and quantum mechanics. The theory is still being developed, some problems are being solved and the main one is the experimental problem, because it requires energy levels that are not yet achieved by current particle accelerators. This work presents M theory as a possibility of unification between the micro and macro, which maybe leading us to the theory of everything. (author)
Explaining the electroweak scale and stabilizing moduli in M theory
International Nuclear Information System (INIS)
Acharya, Bobby S.; Bobkov, Konstantin; Kane, Gordon L.; Kumar, Piyush; Shao Jing
2007-01-01
In a recent paper [B. Acharya, K. Bobkov, G. Kane, P. Kumar, and D. Vaman, Phys. Rev. Lett. 97, 191601 (2006).] it was shown that in fluxless M theory vacua with at least two hidden sectors undergoing strong gauge dynamics and a particular form of the Kaehler potential, all moduli are stabilized by the effective potential and a stable hierarchy is generated, consistent with standard gauge unification. This paper explains the results of [B. Acharya, K. Bobkov, G. Kane, P. Kumar, and D. Vaman, Phys. Rev. Lett. 97, 191601 (2006).] in more detail and generalizes them, finding an essentially unique de Sitter vacuum under reasonable conditions. One of the main phenomenological consequences is a prediction which emerges from this entire class of vacua: namely, gaugino masses are significantly suppressed relative to the gravitino mass. We also present evidence that, for those vacua in which the vacuum energy is small, the gravitino mass, which sets all the superpartner masses, is automatically in the TeV-100 TeV range
Explaining the electroweak scale and stabilizing moduli in M theory
Acharya, Bobby S.; Bobkov, Konstantin; Kane, Gordon L.; Kumar, Piyush; Shao, Jing
2007-12-01
In a recent paper [B. Acharya, K. Bobkov, G. Kane, P. Kumar, and D. Vaman, Phys. Rev. Lett. 97, 191601 (2006).PRLTAO0031-900710.1103/PhysRevLett.97.191601] it was shown that in fluxless M theory vacua with at least two hidden sectors undergoing strong gauge dynamics and a particular form of the Kähler potential, all moduli are stabilized by the effective potential and a stable hierarchy is generated, consistent with standard gauge unification. This paper explains the results of [B. Acharya, K. Bobkov, G. Kane, P. Kumar, and D. Vaman, Phys. Rev. Lett. 97, 191601 (2006).PRLTAO0031-900710.1103/PhysRevLett.97.191601] in more detail and generalizes them, finding an essentially unique de Sitter vacuum under reasonable conditions. One of the main phenomenological consequences is a prediction which emerges from this entire class of vacua: namely, gaugino masses are significantly suppressed relative to the gravitino mass. We also present evidence that, for those vacua in which the vacuum energy is small, the gravitino mass, which sets all the superpartner masses, is automatically in the TeV 100 TeV range.
At the end of the string: the M theory
International Nuclear Information System (INIS)
Vanhove, P.
1998-04-01
The first chapter is a general introduction that presents the more or less historical path that led to the discovery of the superstring perturbative theory, to the duality conjectures and eventually to the M-theory. Non-perturbative solutions of supergravity theories and the particular roles of these solutions to superstrings are detailed in chapter 2. The relevant features of extended supersymmetries from super-Poincare algebra are also presented in chapter 2. The superstring considered as a basic perturbative object as well as the non-perturbative solutions of Dirichlet membranes are presented in chapter 3. Static and dynamic properties of these solutions are detailed and discussed in chapter 4. Chapter 5 is dedicated to tests of duality conjectures through the calculation of instanton corrections for various superstring theories. The duality transformation of the heterotic/type-I couple with the SO(32) group are tested. Chapter 5 ends with the explicit computations of non-perturbative contributions for the type-I and type-II theories generated inside the frame of a super Yang-Mill supersymmetric model. The role of a new matrix formulation of the superstring theory is highlighted. (A.C.)
Orbifolds of M-theory and type II string theories in two dimensions
International Nuclear Information System (INIS)
Roy, S.
1997-01-01
We consider several orbifold compactifications of M-theory and theircorresponding type II duals in two space-time dimensions. In particular, we show that while the orbifold compactification of M-theory on T 9 /J 9 is dual to the orbifold compactification of type IIB string theory on T 8 /I 8 , the same orbifold T 8 /I 8 of type IIA string theory is dual to M-theory compactified on a smooth product manifold K3 x T 5 . Similarly, while the orbifold compactification of M-theory on (K3 x T 5 )/σ. J 5 is dual to the orbifold compactification of type IIB string theory on (K3 x T 4 )/σ.I 4 , the same orbifold of type IIA string theory is dual to the orbifold T 4 x (K3 x S 1 )/σ.J 1 of M-theory. The spectrum of various orbifold compactifications of M-theory and type II string theories on both sides are compared giving evidence in favor of these duality conjectures. We also comment on a connection between the Dasgupta-Mukhi-Witten conjecture and the Dabholkar-Park-Sen conjecture for the six-dimensional orbifold models of type IIB string theory and M-theory. (orig.)
1/4-BPS M-theory bubbles with SO(3) x SO(4) symmetry
International Nuclear Information System (INIS)
Kim, Hyojoong; Kim, Kyung Kiu; Kim, Nakwoo
2007-01-01
In this paper we generalize the work of Lin, Lunin and Maldacena on the classification of 1/2-BPS M-theory solutions to a specific class of 1/4-BPS configurations. We are interested in the solutions of 11 dimensional supergravity with SO(3) x SO(4) symmetry, and it is shown that such solutions are constructed over a one-parameter familiy of 4 dimensional almost Calabi-Yau spaces. Through analytic continuations we can obtain M-theory solutions having AdS 2 x S 3 or AdS 3 x S 2 factors. It is shown that our result is equivalent to the AdS solutions which have been recently reported as the near-horizon geometry of M2 or M5-branes wrapped on 2 or 4-cycles in Calabi-Yau threefolds. We also discuss the hierarchy of M-theory bubbles with different number of supersymmetries
Oriented matroid theory as a mathematical framework for M-theory
Nieto, J. A.
2006-01-01
We claim that $M$(atroid) theory may provide a mathematical framework for an underlying description of $M$-theory. Duality is the key symmetry which motivates our proposal. The definition of an oriented matroid in terms of the Farkas property plays a central role in our formalism. We outline how this definition may be carried over $M$-theory. As a consequence of our analysis we find a new type of action for extended systems which combines dually the $p$-brane and its dual $p^{\\perp}$-brane.
From F/M-theory to K-theory and back
International Nuclear Information System (INIS)
Garcia-Etxebarria, Inaki; Uranga, Angel M.
2006-01-01
We consider discrete K-theory tadpole cancellation conditions in type IIB orientifolds with magnetised 7-branes. Cancellation of K-theory charge constrains the choices of world-volume magnetic fluxes on the latter. We describe the F-/M-theory lift of these configurations, where 7-branes are encoded in the geometry of an elliptic fibration, and their magnetic quanta correspond to supergravity 4-form field strength fluxes. In a K3 compactification example, we show that standard quantization of 4-form fluxes as integer cohomology classes in K3 automatically implies the K-theory charge cancellation constraints on the 7-brane worldvolume magnetic fluxes in string theory (as well as new previously unnoticed discrete constraints, which we also interpret). Finally, we show that flux quantization in F-/M-theory implies that 7-brane world-volume flux quantization conditions are modified in the presence of 3-form fluxes
Alpha- and Omega-Deformations from fluxes in M-Theory
Lambert, Neil; Reffert, Susanne
2014-01-01
We discuss an SL(2,R) family of deformed N=2 four-dimensional gauge theories which we derive from a flux background in M-theory. In addition to the Omega-deformation this family includes a new deformation, which we call the Alpha-deformation, which can be viewed as an S-dual to the Omega-deformation. We study these gauge theories in two ways: by constructing a non-Abelian (but UV-complete) Lagrangian, and by their strong coupling lift to M-theory where their low-energy dynamics can be determined by examining the equation of motion of a single M5-brane wrapped on a Riemann surface.
Breaking E8 to SO(16) in M-theory and F-theory
International Nuclear Information System (INIS)
Aldabe, F.
1998-01-01
M-theory on an 11-dimensional manifold with a boundary must have E 8 gauge groups at each boundary in order to cancel anomalies. The type IA supergravity must have SO(16) gauge group at each boundary in order to be a consistent theory. The latter action can be obtained from the former one via dimensional reduction. Here we make use of the current algebra of the open membrane which couples to the former action to explain why the gauge group E 8 breaks down to SO(16) in going from M-theory to type IA supergravity. We also use the same current algebra to explain why F-theory has an E 8 x E 8 gauge group in its strong coupling limit while it has an SO(16) x SO(16) gauge group in its weak coupling limit. (orig.)
KK-monopoles and G-structures in M-theory/type IIA reductions
International Nuclear Information System (INIS)
Danielsson, Ulf; Dibitetto, Giuseppe; Guarino, Adolfo
2015-01-01
We argue that M-theory/massive IIA backgrounds including KK-monopoles are suitably described in the language of G-structures and their intrinsic torsion. To this end, we study classes of minimal supergravity models that admit an interpretation as twisted reductions in which the twist parameters are not restricted to satisfy the Jacobi constraints ω ω=0 required by an ordinary Scherk-Schwarz reduction. We first derive the correspondence between four-dimensional data and torsion classes of the internal space and, then, check the one-to-one correspondence between higher-dimensional and four-dimensional equations of motion. Remarkably, the whole construction holds regardless of the Jacobi constraints, thus shedding light upon the string/M-theory interpretation of (smeared) KK-monopoles.
From F/M-theory to K-theory and back
Garcia-Etxebarria, I; Garcia-Etxebarria, Inaki; Uranga, Angel M.
2006-01-01
We consider discrete K-theory tadpole cancellation conditions in type IIB orientifolds with magnetised 7-branes. Cancellation of K-theory charge constrains the choices of world-volume magnetic fluxes on the latter. We describe the F-/M-theory lift of these configurations, where 7-branes are encoded in the geometry of an elliptic fibration, and their magnetic quanta correspond to supergravity 4-form field strength fluxes. In a K3 compactification example, we show that standard quantization of 4-form fluxes as integer cohomology classes in K3 automatically implies the K-theory charge cancellation constraints on the 7-brane worldvolume magnetic fluxes in string theory (as well as new previously unnoticed discrete constraints, which we also interpret). Finally, we show that flux quantization in F-/M-theory implies that 7-brane world-volume flux quantization conditions are modified in the presence of 3-form fluxes.
Inflation from M-theory with fourth-order corrections and large extra dimensions
International Nuclear Information System (INIS)
Maeda, Kei-ichi; Ohta, Nobuyoshi
2004-01-01
We study inflationary solutions in the M-theory. Including the fourth-order curvature correction terms, we find three generalized de Sitter solutions, in which our 3-space expands exponentially. Taking one of the solutions, we propose an inflationary scenario of the early universe. This provides us a natural explanation for large extra dimensions in a brane world, and suggests some connection between the 60 e-folding expansion of inflation and TeV gravity based on the large extra dimensions
The number of elementary particles in a fractal M-theory of 11.2360667977 dimensions
International Nuclear Information System (INIS)
He, J.-H.
2007-01-01
It is generally accepted that there are 60 experimentally found particles. The standard model strongly predicts two more hypothetical particles, the Higgs and the graviton. This paper reveals other possible scenario for predicting 69 particles at different energy scales in 11+φ 3 fractal dimensions of a fractal M theory, where φ=(5-1)/2. A modified Newton's law is suggested to experimentally verify our predictions at extremely small quantum scales. The modified Newton's law is in harmony with Heisenberg's uncertainty principle
On N = 1 gauge models from geometric engineering in M-theory
International Nuclear Information System (INIS)
Belhaj, A; Drissi, L B; Rasmussen, J
2003-01-01
We study geometric engineering of four-dimensional N = 1 gauge models from M-theory on a seven-dimensional manifold with G 2 holonomy. The manifold is constructed as a K3 fibration over a three-dimensional base space with ADE geometry. The resulting gauge theory is discussed in the realm of (p, q) webs. We discuss how the anomaly cancellation condition translates into a condition on the associated affine ADE Lie algebras
Hawking radiation from four-dimensional Schwarzschild black holes in M theory
International Nuclear Information System (INIS)
Das, S.R.; Mathur, S.D.; Ramadevi, P.
1999-01-01
Recently a method has been developed for relating four dimensional Schwarzschild black holes in M theory to near-extremal black holes in string theory with four charges, using suitably defined open-quotes boostsclose quotes and T dualities. We show that this method can be extended to obtain the emission rate of low energy massless scalars for the four dimensional Schwarzschild hole from the microscopic picture of radiation from the near extremal hole. copyright 1999 The American Physical Society
G{sub 2}-structures and quantization of non-geometric M-theory backgrounds
Energy Technology Data Exchange (ETDEWEB)
Kupriyanov, Vladislav G. [Centro de Matemática, Computação e Cognição, Universidade de Federal do ABC,Santo André, SP (Brazil); Tomsk State University,Tomsk (Russian Federation); Szabo, Richard J. [Department of Mathematics, Heriot-Watt University,Colin Maclaurin Building, Riccarton, Edinburgh EH14 4AS (United Kingdom); Maxwell Institute for Mathematical Sciences,Edinburgh (United Kingdom); The Higgs Centre for Theoretical Physics,Edinburgh (United Kingdom)
2017-02-20
We describe the quantization of a four-dimensional locally non-geometric M-theory background dual to a twisted three-torus by deriving a phase space star product for deformation quantization of quasi-Poisson brackets related to the nonassociative algebra of octonions. The construction is based on a choice of G{sub 2}-structure which defines a nonassociative deformation of the addition law on the seven-dimensional vector space of Fourier momenta. We demonstrate explicitly that this star product reduces to that of the three-dimensional parabolic constant R-flux model in the contraction of M-theory to string theory, and use it to derive quantum phase space uncertainty relations as well as triproducts for the nonassociative geometry of the four-dimensional configuration space. By extending the G{sub 2}-structure to a Spin(7)-structure, we propose a 3-algebra structure on the full eight-dimensional M2-brane phase space which reduces to the quasi-Poisson algebra after imposing a particular gauge constraint, and whose deformation quantisation simultaneously encompasses both the phase space star products and the configuration space triproducts. We demonstrate how these structures naturally fit in with previous occurences of 3-algebras in M-theory.
Non-Kähler resolved conifold, localized fluxes in M-theory and supersymmetry
International Nuclear Information System (INIS)
Dasgupta, Keshav; Emelin, Maxim; McDonough, Evan
2015-01-01
The known supergravity solution for wrapped D5-branes on the two-cycle of a Kähler resolved conifold is in general ISD but not supersymmetric, with the supersymmetry being broken by the presence of (1, 2) fluxes. However if we allow a non-Kähler metric on the resolved conifold, supersymmetry can easily be restored. The vanishing of the (1, 2) fluxes here corresponds to, under certain conformal rescalings of the metric, the torsion class constraints. We construct a class of explicit non-Kähler metrics on the resolved conifold satisfying the constraints. All this can also be studied from M-theory, where the fluxes and branes become non-localized G-fluxes on deformed Taub-NUT spaces. Interestingly, the gauge fluctuations on the wrapped D5-branes appear now as localized G-fluxes in M-theory. These localized fluxes are related to certain harmonic two-forms that are normalizable. We compute these forms explicitly and discuss how new constraints on the geometry of the non-Kähler manifolds may appear from M-theory considerations.
Flux compactification of M-theory on compact manifolds with Spin(7) holonomy
International Nuclear Information System (INIS)
Constantin, D.
2005-01-01
At the leading order, M-theory admits minimal supersymmetric compactifications if the internal manifold has exceptional holonomy. The inclusion of non-vanishing fluxes in M-theory and string theory compactifications induce a superpotential in the lower dimensional theory, which depends on the fluxes. In this work, we check the conjectured form of this superpotential in the case of warped M-theory compactifications on Spin(7) holonomy manifolds. We perform a Kaluza-Klein reduction of the eleven-dimensional supersymmetry transformation for the gravitino and we find by direct comparison the superpotential expression. We check the conjecture for the heterotic string compactified on a Calabi-Yau three-fold as well. The conjecture can be checked indirectly by inspecting the scalar potential obtained after the compactification of M-theory on Spin(7) holonomy manifolds with non-vanishing fluxes. The scalar potential can be written in terms of the superpotential and we show that this potential stabilizes all the moduli fields describing deformations of the metric except for the radial modulus. All the above analyses require the knowledge of the minimal supergravity action in three dimensions. Therefore we calculate the most general causal N =1 three-dimensional, gauge invariant action coupled to matter in superspace and derive its component form using Ectoplasmic integration theory. We also show that the three-dimensional theory which results from the compactification is in agreement with the more general supergravity construction. The compactification procedure takes into account higher order quantum correction terms in the low energy effective action. We analyze the properties of these terms on a Spin(7) background. We derive a perturbative set of solutions which emerges from a warped compactification on a Spin(7) holonomy manifold with non-vanishing flux for the M-theory field strength and we show that in general the Ricci flatness of the internal manifold is lost, which
M-theory on Spin(7) manifolds, fluxes and 3D, N=1 supergravity
International Nuclear Information System (INIS)
Becker, Melanie; Constantin, Dragos; Gates, S. James; Linch, William D.; Merrell, Willie; Phillips, J.
2004-01-01
We calculate the most general causal N=1 three-dimensional, gauge invariant action coupled to matter in superspace and derive its component form using ectoplasmic integration theory. One example of such an action can be obtained by compactifying M-theory on a Spin(7) holonomy manifold taking non-vanishing fluxes into account. We show that the resulting three-dimensional theory is in agreement with the more general construction. The scalar potential resulting from Kaluza-Klein compactification stabilizes all the moduli fields describing deformations of the metric except for the radial modulus. This potential can be written in terms of the superpotential previously discussed in the literature
M-theory on Spin(7) manifolds, fluxes and 3D, N=1 supergravity
Energy Technology Data Exchange (ETDEWEB)
Becker, Melanie E-mail: melanieb@physics.umd.edu; Constantin, Dragos E-mail: dragos@physics.umd.edu; Gates, S. James E-mail: gatess@wam.umd.edu; Linch, William D. E-mail: ldw@physics.umd.edu; Merrell, Willie E-mail: williem@physics.umd.edu; Phillips, J. E-mail: ferrigno@physics.umd.edu
2004-04-05
We calculate the most general causal N=1 three-dimensional, gauge invariant action coupled to matter in superspace and derive its component form using ectoplasmic integration theory. One example of such an action can be obtained by compactifying M-theory on a Spin(7) holonomy manifold taking non-vanishing fluxes into account. We show that the resulting three-dimensional theory is in agreement with the more general construction. The scalar potential resulting from Kaluza-Klein compactification stabilizes all the moduli fields describing deformations of the metric except for the radial modulus. This potential can be written in terms of the superpotential previously discussed in the literature.
Generalized space-time supersymmetries, division algebras and octonionic M-theory
International Nuclear Information System (INIS)
Lukierski, Jerzy; Toppan, Francesco
2002-03-01
We describe the set of generalized Poincare and conformal superalgebras in D= 4,5 and 7 dimensions as two sequences of superalgebraic structures, taking values in the division algebras R, C and H. The generalized conformal superalgebras are described for D = 4 by OSp(1;8|R), for D = 5 by SU(4,4;1) and for D = 7 by U α U (8;1|H). The relation with other schemes, in particular the framework of conformal spin (super) algebras and Jordan (super) algebras is discussed. By extending the division-algebra-valued super-algebras to octonions we get in D= 11 an octonionic generalized Poincare superalgebra, which we call octonionic M-algebra, describing the octonionic M-theory. It contains 32 real supercharges but, due to the octonionic structure only 52 real bosonic generators remain independent in place of the 528 bosonic charges of standard M-algebra. In octonionic M-theory there is a sort of equivalence between the octonionic M2 (supermembrane) and the octonionic M5 (super-5-brane) sectors. We also define the octonionic generalized conformal M-superalgebra with 239 bosonic generators. (author)
M-theory and U-duality on Td with gauge backgrounds
International Nuclear Information System (INIS)
Obers, N.A.; Pioline, B.; Rabinovici, E.
1998-01-01
The full U-duality symmetry of toroidally compactified M-theory can only be displayed by allowing non-rectangular tori with expectation values of the gauge fields. We construct an E d (Z) U-duality invariant mass formula incorporating non-vanishing gauge backgrounds of the M-theory three-form C. We interpret this mass formula from the point of view of the matrix gauge theory, and identify the coupling of the three-form to the gauge theory as a topological theta term, in agreement with earlier conjectures. We give a derivation of this fact from D-brane analysis, and obtain the matrix gauge theory description of other gauge backgrounds allowed by the discrete light-cone quantization. We further show that the conjectured extended U-duality symmetry of matrix theory on T d in the discrete light-cone quantization has an implementation as an action of E d+1 (Z) on the BPS spectrum. Some implications for the proper interpretation of the rank N of the matrix gauge theory are discussed. (orig.)
Heterotic M-theory, warped geometry and the cosmological constant problem
International Nuclear Information System (INIS)
Krause, A.
2001-01-01
The first part of this thesis analyzes whether a locally flat background represents a stable vacuum for the proposed heterotic M-theory. A calculation of the leading order supergravity exchange diagrams leads to the conclusion that the locally flat vacuum cannot be stable. Afterwards a comparison with the corresponding weakly coupled heterotic string amplitudes is made. Next, we consider compactifications of heterotic M-theory on a Calabi-Yau threefold, including a non-vanishing G-flux. The ensuing warped-geometry is determined completely and used to show that the variation of the Calabi-Yau volume along the orbifold direction varies quadratically with distance instead linearly as suggested by an earlier first order approximation. In the second part of this thesis we propose a mechanism for obtaining a small cosmological constant. This mechanism consists of the separation of two domain-walls, which together constitute our world, up to a distance 2l ≅1/M GUT . The resulting warped-geometry leads to an exponential suppression of the cosmological constant, which thereby can obtain its observed value without introducing a large hierarchy. An embedding of this set-up into IIB string-theory entails an SU(6) grand unified theory with a natural explanation of the Higgs doublet-triplet splitting. Finally, we examine to what extent the string-theory T-duality can influence curvature. To this aim we derive the full transformation of the curvature-tensor under T-duality. (orig.)
M-theory and E10: Billiards, Branes, and Imaginary Roots
Energy Technology Data Exchange (ETDEWEB)
Brown, Jeffrey; Ganor, Ori J.; Helfgott, Craig
2004-01-09
Eleven dimensional supergravity compactified on $T^10$ admits classical solutions describing what is known as billiard cosmology - a dynamics expressible as an abstract (billiard) ball moving in the 10-dimensional root space of the infinite dimensional Lie algebra E10, occasionally bouncing off walls in that space. Unlike finite dimensional Lie algebras, E10 has negative and zero norm roots, in addition to the positive norm roots. The walls above are related to physical fluxes that, in turn, are related to positive norm roots (called real roots) of E10. We propose that zero and negative norm roots, called imaginary roots, are related to physical branes. Adding 'matter' to the billiard cosmology corresponds to adding potential terms associated to imaginary roots. The, as yet, mysterious relation between E10 and M-theory on $T^10$ can now be expanded as follows: real roots correspond to fluxes or instantons, and imaginary roots correspond to particles and branes (in the cases we checked). Interactions between fluxes and branes and between branes and branes are classified according to the inner product of the corresponding roots (again in the cases we checked). We conclude with a discussion of an effective Hamiltonian description that captures some features of M-theory on $T^10.$
The effective action of warped M-theory reductions with higher derivative terms — part I
Energy Technology Data Exchange (ETDEWEB)
Grimm, Thomas W.; Pugh, Tom G.; Weissenbacher, Matthias [Max Planck Institute for Physics,Föhringer Ring 6, 80805 Munich (Germany)
2016-01-25
M-theory accessed via eleven-dimensional supergravity admits globally consistent warped solutions with eight-dimensional compact spaces if background fluxes and higher derivative terms are considered. The internal background is conformally Kähler with vanishing first Chern class. We perturb these solutions including a finite number of Kähler deformations of the metric and vector deformations of the M-theory three-form. Special emphasis is given to the field-dependence of the warp-factor and the higher-derivative terms. We show that the three-dimensional two-derivative effective action takes a surprisingly simple form in terms of a single higher-curvature building block due to numerous non-trivial cancellations. Both the ansatz and the effective action admit a moduli dependent scaling symmetry of the internal metric. Furthermore, we find that the required departure from Ricci-flatness and harmonicity of the zero-mode eigenforms does not alter the effective theory.
Strong Coupling Dynamics of Four-Dimensional N=1 Gauge Theories from M Theory Fivebrane
International Nuclear Information System (INIS)
Hori, K.; Ooguri, H.; Oz, Y.
1997-01-01
It has been known that the fivebrane of type IIA theory can be used to give an exact low energy description of N=2 supersymmetric gauge theories in four dimensions. We follow the recent M theory description by Witten and show that it can be used to study theories with N=1 supersymmetry. The N=2 supersymmetry can be broken to N=1 by turning on a mass for the adjoint chiral superfield in the N=2 vector multiplet. We construct the configuration of the fivebrane for both finite and infinite values of the adjoint mass. The fivebrane describes strong coupling dynamics of N=1 theory with SU(N c ) gauge group and N f quarks. For N c > N f , we show how the brane configuration encodes the information of the Affleck-Dine-Seiberg superpotential. For N c and f , we study the deformation space of the brane configuration and compare it with the moduli space of the N=1 theory. We find agreement with field theory results, including the quantum deformation of the moduli space at N c = N f . We also prove the type II s-rule in M theory and find new non-renormalization theorems for N = 1 superpotentials
M2- and M5-branes in E11 current algebra formulation of M-theory
Shiba, Shotaro; Sugawara, Hirotaka
2018-03-01
Equations of motion for M2- and M5-branes are written down in the E11 current algebra formulation of M-theory. These branes correspond to currents of the second and the fifth rank antisymmetric tensors in the E11 representation, whereas the electric and magnetic fields (coupled to M2- and M5-branes) correspond to currents of the third and the sixth rank antisymmetric tensors, respectively. We show that these equations of motion have solutions in terms of the coordinates on M2- and M5-branes. We also discuss the geometric equations, and show that there are static solutions when M2- or M5-brane exists alone and also when M5-brane wraps around M2-brane. This situation is realized because our Einstein-like equation contains an extra term which can be interpreted as gravitational energy contributing to the curvature, thus avoiding the usual intersection rule.
The domain walls of gauged maximal supergravities and their M-theory origin
International Nuclear Information System (INIS)
Bergshoe, Eric; Nielsen, Mikkel; Roest, Diederik
2004-01-01
We consider gauged maximal supergravities with CSO(p,q,r) gauge groups and their relation to the branes of string and M-theory. The gauge groups are characterised by n mass parameters, where n is the transverse dimension of the brane. We give the scalar potentials and construct the corresponding domain wall solutions. In addition, we show the higher-dimensional origin of the domain walls in terms of (distributions of) branes. We put particular emphasis on the CSO(p,q,r) gauged supergravities in D = 9 and D = 8, which are related to the D7-brane and D6-brane, respectively. In these cases, twisted and group manifold reductions are shown to play a crucial role. We also discuss salient features of the corresponding brane distributions. (author)
M Theory on AdSp x S11-p and superconformal field theories
International Nuclear Information System (INIS)
Aharony, Ofer; Yaron, Oz; Zheng, Yin
1998-01-01
We study the large N limit of the interacting superconformal field theories associated with N M5 branes or M2 branes using the recently proposed relation between these theories and M theory on AdS spaces. We first analyze the spectrum of chiral operators of the 6d (0, 2) theory associated with M5 branes in flat space, and find full agreement with earlier results obtained using its DLCQ description as quantum mechanics on a moduli space of instantons. We then perform a similar analysis for the D N type 6d (0, 2) theories associated with M5 branes at an R 5 /Z 2 singularity, and for the 3d N = 8 superconformal field theories associated with M2 branes in flat space and at an R 8 /Z 2 singularity respectively. Little is known about these three theories, and our study yields for the first time their spectrum of chiral operators (in the large N limit)
Orbifold compactification and solutions of M-theory from Milne spaces
International Nuclear Information System (INIS)
Bytsenko, A.A.; Guimaraes, M.E.X.; Kerner, R.
2005-01-01
In this paper, we consider solutions and spectral functions of M-theory from Milne spaces with extra free dimensions. Conformal deformations to the metric associated with real hyperbolic space forms are derived. For the three-dimensional case, the orbifold identifications SL(2,Z+iZ)/{±Id}, where Id is the identity matrix, is analyzed in detail. The spectrum of an eleven-dimensional field theory can be obtained with the help of the theory of harmonic functions in the fundamental domain of this group and it is associated with the cusp forms and the Eisenstein series. The supersymmetry surviving for supergravity solutions involving real hyperbolic space factors is briefly discussed. (orig.)
Sakurai Prize: Why the Higgs Boson data implies an M-theory world
Kane, Gordon
2017-01-01
Compactifying 11D M-theory on a 7D G2 manifold automatically gives a supersymmetric 4D relativistic quantum field theory. The supersymmetry is softly broken by gluino condensation of the largest gauge group hidden sector, which runs fastest. The resulting gravitino mass is about 40 TeV, and the scalar masses and trilinears of the soft breaking Lagrangian have similar values. All solutions having electroweak symmetry breaking are in the two doublet decoupling region. The coefficient λ of the effective Higgs potential is calculable and determines Mh/MZ. Using the most recent match and run methods, and running down to the TeV scale gives Mh = 126 GeV, and decay BR within a few per cent of the SM Higgs. This was reported in summer 2011, before LHC data, though the result does not depend on any adjustable parameters so it would be unchanged whenever it was reported.
On thermodynamics of AdS black holes in M-theory
Energy Technology Data Exchange (ETDEWEB)
Belhaj, A. [Universite Sultan Moulay Slimane, Departement de Physique, LIRST, Faculte Polydisciplinaire, Beni Mellal (Morocco); Cadi Ayyad University, High Energy Physics and Astrophysics Laboratory, FSSM, Marrakesh (Morocco); Chabab, M.; Masmar, K. [Cadi Ayyad University, High Energy Physics and Astrophysics Laboratory, FSSM, Marrakesh (Morocco); El Moumni, H. [Cadi Ayyad University, High Energy Physics and Astrophysics Laboratory, FSSM, Marrakesh (Morocco); Universite Ibn Zohr, Departement de Physique, Faculte des Sciences, Agadir (Morocco); Sedra, M.B. [Universite Ibn Tofail, Departement de Physique, LASIMO, Faculte des Sciences, Kenitra (Morocco)
2016-02-15
Motivated by recent work on asymptotically AdS{sub 4} black holes in M-theory, we investigate the thermodynamics and thermodynamical geometry of AdS black holes from M2- and M5-branes. Concretely, we consider AdS black holes in AdS{sub p+2} x S{sup 11-p-2}, where p = 2,5 by interpreting the number of M2- (and M5-branes) as a thermodynamical variable. More precisely, we study the corresponding phase transition to examine their stabilities by calculating and discussing various thermodynamical quantities including the chemical potential. Then we compute the thermodynamical curvatures from the Quevedo metric for M2- and M5-branes geometries to reconsider the stability of such black holes. The Quevedo metric singularities recover similar stability results provided by the phase-transition program. It has been shown that similar behaviors are also present in the limit of large N. (orig.)
World-volume effective action of exotic five-brane in M-theory
International Nuclear Information System (INIS)
Kimura, Tetsuji; Sasaki, Shin; Yata, Masaya
2016-01-01
We study the world-volume effective action of an exotic five-brane, known as the M-theory 5"3-brane (M5"3-brane) in eleven dimensions. The supermultiplet of the world-volume theory is the N=(2,0) tensor multiplet in six dimensions. The world-volume action contains three Killing vectors k̂_I_̂"M (Î=1,2,3) associated with the U(1)"3 isometry. We find the effective T-duality rule for the eleven-dimensional backgrounds that transforms the M5-brane effective action to that of the M5"3-brane. We also show that our action provides the source term for the M5"3-brane geometry in eleven-dimensional supergravity.
World-volume effective action of exotic five-brane in M-theory
Energy Technology Data Exchange (ETDEWEB)
Kimura, Tetsuji [Research and Education Center for Natural Sciences, Keio University, Hiyoshi 4-1-1, Yokohama, Kanagawa 223-8521 (Japan); Department of Physics, Tokyo Institute of Technology,Tokyo 152-8551 (Japan); Sasaki, Shin [Department of Physics, Kitasato University,Sagamihara 252-0373 (Japan); Yata, Masaya [Department of Physics, National University of Singapore,2, Science Drive 3, Singapore 117542 (Singapore)
2016-02-25
We study the world-volume effective action of an exotic five-brane, known as the M-theory 5{sup 3}-brane (M5{sup 3}-brane) in eleven dimensions. The supermultiplet of the world-volume theory is the N=(2,0) tensor multiplet in six dimensions. The world-volume action contains three Killing vectors k̂{sub Î}{sup M} (Î=1,2,3) associated with the U(1){sup 3} isometry. We find the effective T-duality rule for the eleven-dimensional backgrounds that transforms the M5-brane effective action to that of the M5{sup 3}-brane. We also show that our action provides the source term for the M5{sup 3}-brane geometry in eleven-dimensional supergravity.
On thermodynamics of AdS black holes in M-theory
International Nuclear Information System (INIS)
Belhaj, A.; Chabab, M.; Masmar, K.; El Moumni, H.; Sedra, M.B.
2016-01-01
Motivated by recent work on asymptotically AdS 4 black holes in M-theory, we investigate the thermodynamics and thermodynamical geometry of AdS black holes from M2- and M5-branes. Concretely, we consider AdS black holes in AdS p+2 x S 11-p-2 , where p = 2,5 by interpreting the number of M2- (and M5-branes) as a thermodynamical variable. More precisely, we study the corresponding phase transition to examine their stabilities by calculating and discussing various thermodynamical quantities including the chemical potential. Then we compute the thermodynamical curvatures from the Quevedo metric for M2- and M5-branes geometries to reconsider the stability of such black holes. The Quevedo metric singularities recover similar stability results provided by the phase-transition program. It has been shown that similar behaviors are also present in the limit of large N. (orig.)
Supermatrix models for M-theory based on osp(1 vertical bar 32, R)
International Nuclear Information System (INIS)
Bagnoud, Maxime; Carlevaro, Luca; Bilal, Adel
2002-01-01
Taking seriously the hypothesis that the full symmetry algebra of M-theory is osp(1 vertical bar 32, R), we derive the supersymmetry transformations for all fields that appear in 11- and 12-dimensional realizations and give the associated SUSY algebras. We study the background-independent osp(1 vertical bar 32, R) cubic matrix model action expressed in terms of representations of the Lorentz groups SO(10,2) and SO(10,1). We explore further the 11-dimensional case and compute an effective action for the BFSS-like degrees of freedom. We find the usual BFSS action with additional terms incorporating couplings to transverse 5-branes, as well as a mass-term and an infinite tower of higher-order interactions
Moving five-branes and membrane instantons in low energy heterotic M theory
International Nuclear Information System (INIS)
Carlos, Beatriz de; Roberts, Jonathan; Schmoehe, Yaiza
2005-01-01
We study cosmological solutions in the context of four-dimensional low energy heterotic M theory with moving bulk branes. First we present nontrivial, analytic axion solutions generated by new symmetries of the full potential-free action, and we discuss their relation to 'triple axion' solutions found in Pre-Big-Bang cosmologies. Next we consider the presence of a nonperturbative superpotential with and without a background perfect fluid. In the absence of a fluid the dilaton and the T-modulus go to the potential-free solutions at late time, while the moving brane tries to avoid colliding with the boundary and stabilize within the bulk. When the fluid is included the dynamics of the fields change, and we study their behavior both numerically and analytically. In particular we examine the possibility of this setup being a realization of the quintessential scenario and the impact of the fluid on the cosmological stabilization of the moduli
Stokes phenomena and quantum integrability in non-critical string/M theory
International Nuclear Information System (INIS)
Chan, Chuan-Tsung; Irie, Hirotaka; Yeh, Chi-Hsien
2012-01-01
We study Stokes phenomena of the k×k isomonodromy systems with an arbitrary Poincaré index r, especially which correspond to the fractional-superstring (or parafermionic-string) multi-critical points (p-hat,q-hat)=(1,r-1) in the k-cut two-matrix models. Investigation of this system is important for the purpose of figuring out the non-critical version of M theory which was proposed to be the strong-coupling dual of fractional superstring theory as a two-matrix model with an infinite number of cuts. Surprisingly the multi-cut boundary-condition recursion equations have a universal form among the various multi-cut critical points, and this enables us to show explicit solutions of Stokes multipliers in quite wide classes of (k,r). Although these critical points almost break the intrinsic Z k symmetry of the multi-cut two-matrix models, this feature makes manifest a connection between the multi-cut boundary-condition recursion equations and the structures of quantum integrable systems. In particular, it is uncovered that the Stokes multipliers satisfy multiple Hirota equations (i.e. multiple T-systems). Therefore our result provides a large extension of the ODE/IM correspondence to the general isomonodromy ODE systems endowed with the multi-cut boundary conditions. We also comment about a possibility that N=2 QFT of Cecotti-Vafa would be “topological series” in non-critical M theory equipped with a single quantum integrability.
Supernatural supersymmetry and its classic example: M-theory inspired NMSSM
Li, Tianjun; Raza, Shabbar; Wang, Xiao-Chuan
2016-06-01
We briefly review the supernatural supersymmetry (SUSY), which provides a most promising solution to the SUSY electroweak fine-tuning problem. In particular, we address its subtle issues as well. Unlike the minimal supersymmetric standard model (MSSM), the next to MSSM (NMSSM) can be scale invariant and has no mass parameter in its Lagrangian before SUSY and gauge symmetry breakings. Therefore, the NMSSM is a perfect framework for supernatural SUSY. To give the SUSY breaking soft mass to the singlet, we consider the moduli and dilaton dominant SUSY breaking scenarios in M-theory on S1/Z2. In these scenarios, SUSY is broken by one and only one F term of moduli or dilaton, and the SUSY breaking soft terms can be determined via the Kähler potential and superpotential from Calabi-Yau compactification of M-theory on S1/Z2. Thus, as predicted by supernatural SUSY, the SUSY electroweak fine-tuning measure is of unity order. In the moduli dominant SUSY breaking scenario, the right-handed sleptons are relatively light around 1 TeV, stau can even be as light as 580 GeV and degenerate with the lightest neutralino, chargino masses are larger than 1 TeV, the light stop masses are around 2 TeV or larger, the first two-generation squark masses are about 3 TeV or larger, and gluinos are heavier tha.n squarks. In the dilaton dominant SUSY breaking scenario, the qualitative picture remains the same but we have heavier spectra as compared to the moduli dominant SUSY breaking scenario. In addition to it, we have Higgs H2/A1-resonance solutions for dark matter (DM). In both scenarios, the minimal value of DM relic density is about 0.2. To obtain the observed DM relic density, we can consider the dilution effect from supercritical string cosmology or introduce the axino as the lightest supersymmetric particle.
G-theory: The generator of M-theory and supersymmetry
Sepehri, Alireza; Pincak, Richard
2018-04-01
In string theory with ten dimensions, all Dp-branes are constructed from D0-branes whose action has two-dimensional brackets of Lie 2-algebra. Also, in M-theory, with 11 dimensions, all Mp-branes are built from M0-branes whose action contains three-dimensional brackets of Lie 3-algebra. In these theories, the reason for difference between bosons and fermions is unclear and especially in M-theory there is not any stable object like stable M3-branes on which our universe would be formed on it and for this reason it cannot help us to explain cosmological events. For this reason, we construct G-theory with M dimensions whose branes are formed from G0-branes with N-dimensional brackets. In this theory, we assume that at the beginning there is nothing. Then, two energies, which differ in their signs only, emerge and produce 2M degrees of freedom. Each two degrees of freedom create a new dimension and then M dimensions emerge. M-N of these degrees of freedom are removed by symmetrically compacting half of M-N dimensions to produce Lie-N-algebra. In fact, each dimension produces a degree of freedom. Consequently, by compacting M-N dimensions from M dimensions, N dimensions and N degrees of freedom is emerged. These N degrees of freedoms produce Lie-N-algebra. During this compactification, some dimensions take extra i and are different from other dimensions, which are known as time coordinates. By this compactification, two types of branes, Gp and anti-Gp-branes, are produced and rank of tensor fields which live on them changes from zero to dimension of brane. The number of time coordinates, which are produced by negative energy in anti-Gp-branes, is more sensible to number of times in Gp-branes. These branes are compactified anti-symmetrically and then fermionic superpartners of bosonic fields emerge and supersymmetry is born. Some of gauge fields play the role of graviton and gravitino and produce the supergravity. The question may arise that what is the physical reason
Non-supersymmetric flux compactifications of heterotic string- and M-theory
Energy Technology Data Exchange (ETDEWEB)
Held, Johannes Georg Joseph
2012-05-08
This dissertation is concerned with non-supersymmetric vacua of string theory in the supergravity (SUGRA) approach. This approach is the effective description of string theory at low energies. The concrete field of research that is treated here is heterotic E{sub 8} x E{sub 8} string theory at weak and at strong coupling, respectively. In the strong coupling limit the theory is described by eleven-dimensional SUGRA with two ten-dimensional boundaries (heterotic M-Theory). The transition to the weak coupling limit is governed by the restricted space dimension, whose length tends to zero for weak coupling such that the two boundaries get identified with each other. The resulting theory is ten-dimensional E{sub 8} x E{sub 8} SUGRA. In the context of this heterotic SUGRA, at first six of the former nine space-dimensions are compactified, and then, in the presence of non-vanishing background flux, conditions for unbroken supersymmetry (SUSY) in four space-time dimensions are analyzed. Afterwards, a violation of one of the necessary SUSY conditions is allowed. An essential ingredient, necessary for this to work, is the presence of flux. This kind of SUSY-breaking leads to severe constraints on the compact six-dimensional manifold, which can be satisfied by fiber bundles with two-dimensional fiber and four-dimensional base. In simple examples one can stabilize the expectation value of the dilaton as well as the volume of the fiber, whereas the volume of the base remains undetermined. Furthermore, the effect of a fermionic condensate is analyzed. The expected additional SUSY-breaking can be observed, and it is shown that the breaking induced by the flux can not be canceled by the contributions from the condensate. The end of this thesis is concerned with the discussion of the strong coupling limit of the previously found examples. To analyze this, it is necessary to rewrite the action of heterotic M-theory as a sum of quadratic terms, which vanish once SUSY is imposed
International Nuclear Information System (INIS)
Toppan, Francesco
2004-06-01
Relying upon the division-algebra classification of Clifford algebras and spinors, a classification of generalized supersymmetries (or, with a slight abuse of language, 'generalized super translations') is provided. In each given space-time the maximal, saturated, generalized supersymmetry, compatible with the division-algebra constraint that can be consistently imposed on spinors and on superalgebra generators, is furnished. Constraining the superalgebra generators in both the complex and the quaternionic cases gives rise to the two classes of constrained hermitian and holomorphic generalized supersymmetries. In the complex case these two classes of generalized supersymmetries can be regarded as complementary. The quaternionic holomorphic supersymmetry only exists in certain space-time dimensions and can admit at most a single bosonic scalar central charge. The results here presented pave the way for a better understanding of the various M algebra-type of structures which can be introduced in different space-time signatures and in association with different division algebras, as well as their mutual relations. In a previous work, e.g., the introduction of a complex holomorphic generalized supersymmetry was shown to be necessary in order to perform the analytic continuation of the standard M-theory to the 11-dimensional Euclidean space. As an application of the present results, it is shown that the above algebra also admits a 12-dimensional, Euclidean, F-algebra presentation. (author)
G-fluxes and non-perturbative stabilisation of heterotic M-theory
International Nuclear Information System (INIS)
Curio, Gottfried; Krause, Axel
2002-01-01
We examine heterotic M-theory compactified on a Calabi-Yau manifold with an additional parallel M5-brane. The dominant non-perturbative effect stems from open membrane instantons connecting the M5 with the boundaries. We derive the four-dimensional low-energy supergravity potential for this situation including subleading contributions as it turns out that the leading term vanishes after minimisation. At the minimum of the potential the M5 gets stabilised at the middle of the orbifold interval while the vacuum energy is shown to be manifestly positive. Moreover, induced by the non-trivial running of the Calabi-Yau volume along the orbifold which is driven by the G-fluxes, we find that the orbifold-length and the Calabi-Yau volume modulus are stabilised at values which are related by the G-flux of the visible boundary. Finally we determine the supersymmetry-breaking scale and the gravitino mass for this open membrane vacuum
A comment on compactification of M-theory on an (almost) light-like circle
International Nuclear Information System (INIS)
Bilal, A.
1998-01-01
In perturbative quantum field theory the limit of compactification on an almost light-like circle has recently been shown to be plagued by divergences. We argue that the light-like limit for M-theory probably is free of such divergences due to, among others, the existence of the wrapping modes of the membranes. To illustrate this, we consider superstring theory compactified on an almost light-like circle. Specifically, we compute a one-loop four-point amplitude in type II theory. As is well known, if the external states have vanishing momenta in the compact dimension, the divergence in the light-like limit is even stronger than in field theory. However, in the case of present interest, where these external momenta are non-vanishing, there is a subtle compensation and the resulting amplitude has a well defined and finite light-like limit. The net effect of taking the light-like limit is to replace the integration over one of the moduli of the four-punctured torus by a sum over a discrete modulus taking values in a finite lattice on the torus. The same result can also be obtained from a suitably ''Wick rotated'' amplitude computed directly with a compact light-like circle. (orig.)
International Nuclear Information System (INIS)
Toppan, Francesco
2004-01-01
Relying upon the division-algebra classification of Clifford algebras and spinors, a classification of generalized supersymmetries (or, with a slight abuse of language,'generalized supertranslations') is provided. In each given space-time the maximal, saturated, generalized supersymmetry, compatible with the division-algebra constraint that can be consistently imposed on spinors and on superalgebra generators, is furnished. Constraining the superalgebra generators in both the complex and the quaternionic cases gives rise to the two classes of constrained hermitean and holomorphic generalized supersymmetries. In the complex case these two classes of generalized supersymmetries can be regarded as complementary. The quaternionic holomorphic supersymmetry only exists in certain space-time dimensions and can admit at most a single bosonic scalar central charge. The results here presented pave the way for a better understanding of the various M algebra-type of structures which can be introduced in different space-time signatures and in association with different division algebras, as well as their mutual relations. In a previous work, e.g., the introduction of a complex holomorphic generalized supersymmetry was shown to be necessary in order to perform the analytic continuation of the standard M-theory to the 11-dimensional euclidean space. As an application of the present results, it is shown that the above algebra also admits a 12-dimensional, euclidean, F-algebra presentation. (author)
G2-MSSM: An M theory motivated model of particle physics
International Nuclear Information System (INIS)
Acharya, Bobby S.; Bobkov, Konstantin; Kane, Gordon L.; Shao Jing; Kumar, Piyush
2008-01-01
We continue our study of the low energy implications of M theory vacua on G 2 -manifolds, undertaken in B. S. Acharya, K. Bobkov, G. L. Kane, P. Kumar, and J. Shao, Phys. Rev. D 76, 126010 (2007); B. Acharya, K. Bobkov, G. Kane, P. Kumar, and D. Vaman, Phys. Rev. Lett. 97, 191601 (2006), where it was shown that the moduli can be stabilized and a TeV scale generated, with the Planck scale as the only dimensionful input. A well-motivated phenomenological model, the G 2 -MSSM, can be naturally defined within the above framework. In this paper, we study some of the important phenomenological features of the G 2 -MSSM. In particular, the soft supersymmetry breaking parameters and the superpartner spectrum are computed. The G 2 -MSSM generically gives rise to light gauginos and heavy scalars with wino lightest supersymmetric particles when one tunes the cosmological constant. Electroweak symmetry breaking is present but fine-tuned. The G 2 -MSSM is also naturally consistent with precision gauge coupling unification. The phenomenological consequences for cosmology and collider physics of the G 2 -MSSM will be reported in more detail soon.
Introduction to branes and M-theory for relativists and cosmologists
International Nuclear Information System (INIS)
Ohta, Nobuyoshi
2003-01-01
We review the recent developments in superstrings. We start with a brief summary of various consistent superstring theories an discuss T-duality which necessarily leads to the presence of D-branes. The properties of D-branes are summarized and we discuss how these suggests the existence of 11-dimensional quantum theory, M-theory, which is believed to give rise to various superstrings as perturbative expansions around particular backgrounds in the theory. We also discuss the interpretation of brane solutions as black holes in string theories and statistical explanation of Bekenstein-Hawking entropy. The idea behind this interpretation is that there is a fundamental duality between closed (gravity) and open (gauge theory) string degrees of freedom, one of whose manifestation is what is known as AdS/CFT correspondence. The idea is used to discuss the greybody factors for BTZ black holes. Finally the entropy of various black holes are discussed in connection with Cardy-Verlinde formula. (author)
Higher derivatives in Type II and M-theory on Calabi-Yau threefolds
Grimm, Thomas W.; Mayer, Kilian; Weissenbacher, Matthias
2018-02-01
The four- and five-dimensional effective actions of Calabi-Yau threefold compactifications are derived with a focus on terms involving up to four space-time derivatives. The starting points for these reductions are the ten- and eleven-dimensional supergravity actions supplemented with the known eight-derivative corrections that have been inferred from Type II string amplitudes. The corrected background solutions are determined and the fluctuations of the Kähler structure of the compact space and the form-field back-ground are discussed. It is concluded that the two-derivative effective actions for these fluctuations only takes the expected supergravity form if certain additional ten- and eleven-dimensional higher-derivative terms for the form-fields are included. The main results on the four-derivative terms include a detailed treatment of higher-derivative gravity coupled to Kähler structure deformations. This is supplemented by a derivation of the vector sector in reductions to five dimensions. While the general result is only given as an expansion in the fluctuations, a complete treatment of the one-Kähler modulus case is presented for both Type II theories and M-theory.
M-theory on eight-manifolds revisited: N = 1 supersymmetry and generalized Spin(7) structures
International Nuclear Information System (INIS)
Tsimpis, Dimitrios
2006-01-01
The requirement of N = 1 supersymmetry for M-theory backgrounds of the form of a warped product M x w X, where X is an eight-manifold and M is three-dimensional Minkowski or AdS space, implies the existence of a nowhere-vanishing Majorana spinor ξ on X. ξ lifts to a nowhere-vanishing spinor on the auxiliary nine-manifold Y: = X x S 1 , where S 1 is a circle of constant radius, implying the reduction of the structure group of Y to Spin(7). In general, however, there is no reduction of the structure group of X itself. This situation can be described in the language of generalized Spin(7) structures, defined in terms of certain spinors of Spin(TY+T*Y). We express the condition for N = 1 supersymmetry in terms of differential equations for these spinors. In an equivalent formulation, working locally in the vicinity of any point in X in terms of a 'preferred' Spin(7) structure, we show that the requirement of N = 1 supersymmetry amounts to solving for the intrinsic torsion and all irreducible flux components, except for the one lying in the 27 of Spin(7), in terms of the warp factor and a one-form L on X (not necessarily nowhere-vanishing) constructed as a ξ bilinear; in addition, L is constrained to satisfy a pair of differential equations. The formalism based on the group Spin(7) is the most suitable language in which to describe supersymmetric compactifications on eight-manifolds of Spin(7) structure, and/or small-flux perturbations around supersymmetric compactifications on manifolds of Spin(7) holonomy
Strings on AdS2 and the high-energy limit of noncritical M-theory
International Nuclear Information System (INIS)
Horava, Petr; Horava, Petr; Keeler, Cynthia A.
2007-01-01
Noncritical M-theory in 2+1 dimensions has been defined as a double-scaling limit of a nonrelativistic Fermi liquid on a flat two-dimensional plane. Here we study this noncritical M-theory in the limit of high energies, analogous to the alpha(prime) → ∞ limit of string theory. In the related case of two-dimensional Type 0A strings, it has been argued that the conformal alpha(prime) → ∞ limit leads to AdS 2 with a propagating fermion whose mass is set by the value of the RR flux. Here we provide evidence that in the high-energy limit, the natural ground state of noncritical M-theory similarly describes the AdS 2 x S 1 spacetime, with a massless propagating fermion. We argue that the spacetime effective theory in this background is captured by a topological higher-spin extension of conformal Chern-Simons gravity in 2+1 dimensions, consistently coupled to a massless Dirac field. Intriguingly, the two-dimensional plane populated by the original nonrelativistic fermions is essentially the twistor space associated with the symmetry group of the AdS 2 x S 1 spacetime; thus, at least in the high-energy limit, noncritical M-theory can be nonperturbatively described as a 'Fermi liquid on twistor space'
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Bagnoud, Maxime; Carlevaro, Luca
2006-01-01
We study T 11-D-q x T q /Z n orbifold compactifications of eleven-dimensional supergravity and M-theory using a purely algebraic method. Given the description of maximal supergravities reduced on square tori as non-linear coset σ-models, we exploit the mapping between scalar fields of the reduced theory and directions in the tangent space over the coset to construct the orbifold action as a non-Cartan preserving finite order inner automorphism of the complexified U-duality algebra. Focusing on the exceptional serie of Cremmer-Julia groups, we compute the residual U-duality symmetry after orbifold projection and determine the reality properties of their corresponding Lie algebras. We carry out this analysis as far as the hyperbolic e 10 algebra, conjectured to be a symmetry of M-theory. In this case the residual subalgebras are shown to be described by a special class of Borcherds and Kac-Moody algebras, modded out by their centres and derivations. Furthermore, we construct an alternative description of the orbifold action in terms of equivalence classes of shift vectors, and, in D 1, we show that a root of e 10 can always be chosen as the class representative. Then, in the framework of the E 10/10 /K(E 10/10 ) effective σ-model approach to M-theory near a spacelike singularity, we identify these roots with brane configurations stabilizing the corresponding orbifolds. In the particular case of Z 2 orbifolds of M-theory descending to type 0' orientifolds, we argue that these roots can be interpreted as pairs of magnetized D9- and D9'-branes, carrying the lower-dimensional brane charges required for tadpole cancellation. More generally, we provide a classification of all such roots generating Z n product orbifolds for n≤6, and hint at their possible interpretation
On E(11) of M-theory: 1. Hidden Symmetries of Maximal Supergravities and Lego of Dynkin Diagrams
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Nurmagambetov, A.J.
2007-01-01
We review a graphical way of classifying hidden symmetry algebras and groups of D=11, 10 maximal supergravities in terms of Dynkin diagrams, the shapes of which are determined by the bosonic field content of supergravities supermultiplets. The approach we follow is tightly related to the West's conjecture on a hidden symmetry of M-theory, and we discuss benefits of the approach in compare to other ways of searching for hidden symmetries of String Theory
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Hyakutake, Yoshifumi [Faculty of Science, Ibaraki University,Bunkyo 2-1-1, Mito, Ibaraki, 310-8512 (Japan)
2015-09-11
We take into account higher derivative R{sup 4} corrections in M-theory and construct quantum black hole and black string solutions in 11 dimensions up to the next leading order. The quantum black string is stretching along the 11th direction and the Gregory-Laflamme instability is examined at the quantum level. Thermodynamics of the boosted quantum black hole and black string are also discussed. Especially we take the near horizon limit of the quantum black string and investigate its instability quantitatively.
Misra, A
2002-01-01
Following the work on the exact evaluation of the non-perturbative contribution to the superpotential from open-membrane instanton in Heterotic M-theory, we evaluate systematically the contribution to the superpotential of a membrane instanton obtained by wrapping of a single M2-brane, once, on an isolated supersymmetric 3-cycle in a G sub 2 -holonomy manifold. We then try to relate the results obtained to those sketched out. We also do a heat-kernel asymptotics analysis to see whether one gets similar UV-divergent terms for (one or both of) the bosonic and fermionic determinants indicative of (partial) cancellation among them. The answer is in the affirmative, as expected by the supersymmetry of the starting membrane action. This work is a first step, both, in extending the work to the evaluation of non-perturbative superpotentials for non-rigid supersymmetric 3-cycle wrappings, and in understanding the large-N Chern-Simons/closed type-A topological string theory duality from M-theory point of view.
M-theory and stringy corrections to anti-de Sitter black holes and conformal field theories
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Caldarelli, Marco M.; Klemm, Dietmar
1999-01-01
We consider black holes in anti-de Sitter space AdS p+2 (p = 2, 3, 5), which have hyperbolic, flat or spherical event horizons. The O(α' 3 ) corrections (or the leading corrections in powers of the eleven-dimensional Planck length, in the case of M-theory compactifications) to the black hole metrics are computed for the various topologies and dimensions. We investigate the consequences of the stringy or M-theory corrections for the black hole thermodynamics. In particular, we show the emergence of a stable branch of small spherical black holes. Surprisingly, for any of the considered dimension and topologies, the corrected thermodynamical quantities turn out to coincide with those calculated within a simplified approach, which uses only the unperturbed metric. We obtain the corrected Hawking-Page transition temperature for black holes with spherical horizons, and show that for p = 3 this phase transition disappears at a value of α' considerably smaller than that estimated previously by Gao and Li. Using the AdS/CFT correspondence, we determine the S 1 x S 3 N = 4 SYM phase diagram for sufficiently large 't Hooft coupling, and show that the critical point at which the Hawking-Page transition disappears (the correspondence point of Horowitz-Polchinski), occurs at g 2 YM N ∼ 20.5. The d = 4 and d = 7 black hole phase diagrams are also determined, and connection is made with the corresponding boundary CFTs. Finally, for flat and hyperbolic horizons, we show that the leading stringy or M-theory corrections do not give rise to any phase transition. However, if the horizon is compactified to a torus T p or to a quotient of hyperbolic space, H p /Γ, the appearance of light winding modes around non-contractible cycles signal new phase transitions, which in the toroidal case have previously been discussed by Barbon et al. We comment on these phase transitions for SYM on H p /Γ and on T p , when the moduli of the torus are taken into account
WiLE: A Mathematica package for weak coupling expansion of Wilson loops in ABJ(M) theory
Preti, M.
2018-06-01
We present WiLE, a Mathematica® package designed to perform the weak coupling expansion of any Wilson loop in ABJ(M) theory at arbitrary perturbative order. For a given set of fields on the loop and internal vertices, the package displays all the possible Feynman diagrams and their integral representations. The user can also choose to exclude non planar diagrams, tadpoles and self-energies. Through the use of interactive input windows, the package should be easily accessible to users with little or no previous experience. The package manual provides some pedagogical examples and the computation of all ladder diagrams at three-loop relevant for the cusp anomalous dimension in ABJ(M). The latter application gives also support to some recent results computed in different contexts.
Comments on the symmetry of AdS6 solutions in string/M-theory and Killing spinor equations
Directory of Open Access Journals (Sweden)
Hyojoong Kim
2016-09-01
Full Text Available It was recently pointed out in [1] that AdS6 solutions in IIB theory enjoy an extended symmetry structure and the consistent truncation to D=4 internal space leads to a nonlinear sigma model with target SL(3,R/SO(2,1. We continue to study the purely bosonic D=4 effective action, and elucidate how the addition of scalar potential term still allows Killing spinor equations in the absence of gauge fields. In particular, the potential turns out to be a single diagonal component of the coset representative. Furthermore, we perform a general analysis of the integrability conditions of Killing spinor equations and establish that the effective action can be in fact generalized to arbitrary sizes and signatures, e.g. with target SL(n,R/SO(p,n−p and the scalar potential expressible by a single diagonal component of the coset representative. We also comment on a similar construction and its generalizations of effective D=5 purely bosonic non-linear sigma model action related to AdS6 in M-theory.
At the end of the string: the M theory; Au bout de la corde: la theorie M
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Vanhove, P
1998-04-15
The first chapter is a general introduction that presents the more or less historical path that led to the discovery of the superstring perturbative theory, to the duality conjectures and eventually to the M-theory. Non-perturbative solutions of supergravity theories and the particular roles of these solutions to superstrings are detailed in chapter 2. The relevant features of extended supersymmetries from super-Poincare algebra are also presented in chapter 2. The superstring considered as a basic perturbative object as well as the non-perturbative solutions of Dirichlet membranes are presented in chapter 3. Static and dynamic properties of these solutions are detailed and discussed in chapter 4. Chapter 5 is dedicated to tests of duality conjectures through the calculation of instanton corrections for various superstring theories. The duality transformation of the heterotic/type-I couple with the SO(32) group are tested. Chapter 5 ends with the explicit computations of non-perturbative contributions for the type-I and type-II theories generated inside the frame of a super Yang-Mill supersymmetric model. The role of a new matrix formulation of the superstring theory is highlighted. (A.C.)
Kane, Gordon
2015-12-01
String/M-theory is an exciting framework within which we try to understand our universe and its properties. Compactified string/M-theories address and offer solutions to almost every important question and issue in particle physics and particle cosmology. But earlier goals of finding a top-down “vacuum selection” principle and deriving the 4D theory have not yet been realized. Does that mean we should stop trying, as nearly all string theorists have? Or can we proceed in the historical way to make a few generic, robust assumptions not closely related to observables, and follow where they lead to testable predictions and explanations? Making only very generic assumptions is a significant issue. I discuss how to try to proceed with this approach, particularly in M-theory compactified on a 7D manifold of G2 holonomy. One goal is to understand our universe as a string/M-theory vacuum for its own sake, in the long tradition of trying to understand our world, and what that implies. In addition, understanding our vacuum may be a prelude to understanding its connection to the multiverse.
International Nuclear Information System (INIS)
Naculich, S.G.; Schnitzer, H.J.
1998-01-01
One-instanton predictions are obtained from the Seiberg-Witten curve derived from M-theory by Landsteiner and Lopez for the Coulomb branch of N=2 supersymmetric SU(N) gauge theory with a matter hypermultiplet in the antisymmetric representation. Since this cubic curve describes a Riemann surface that is non-hyperelliptic, a systematic perturbation expansion about a hyperelliptic curve is developed, with a comparable expansion for the Seiberg-Witten differential. Calculation of the period integrals of the SW differential by the method of residues of D'Hoker, Krichever, and Phong enables us to compute the prepotential explicitly to one-instanton order. It is shown that the one-instanton predictions for SU(2), SU(3), and SU(4) agree with previously available results. For SU(N), N≥5, our analysis provides explicit predictions of a curve derived from M-theory at the one-instanton level in field theory. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Günaydin, Murat [Institute for Gravitation and the Cosmos, Physics Department,Pennsylvania State University, University Park, PA 16802 (United States); Lüst, Dieter [Arnold Sommerfeld Center for Theoretical Physics, Department für Physik, Ludwig-Maximilians-Universität München, Theresienstraße 37, 80333 München (Germany); Max-Planck-Institut für Physik, Werner-Heisenberg-Institut, Föhringer Ring 6, 80805 München (Germany); Malek, Emanuel [Arnold Sommerfeld Center for Theoretical Physics, Department für Physik, Ludwig-Maximilians-Universität München, Theresienstraße 37, 80333 München (Germany)
2016-11-07
We propose a non-associative phase space algebra for M-theory backgrounds with locally non-geometric fluxes based on the non-associative algebra of octonions. Our proposal is based on the observation that the non-associative algebra of the non-geometric R-flux background in string theory can be obtained by a proper contraction of the simple Malcev algebra generated by imaginary octonions. Furthermore, by studying a toy model of a four-dimensional locally non-geometric M-theory background which is dual to a twisted torus, we show that the non-geometric background is “missing” a momentum mode. The resulting seven-dimensional phase space can thus be naturally identified with the imaginary octonions. This allows us to interpret the full uncontracted algebra of imaginary octonions as the uplift of the string theory R-flux algebra to M-theory, with the contraction parameter playing the role of the string coupling constant g{sub s}.
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Gong Yungui; Wang Anzhong; Wu Qiang
2008-01-01
Orbifold branes are studied in the framework of the 11-dimensional Horava-Witten heterotic M-theory. It is found that the effective cosmological constant can be easily lowered to its current observational value by the mechanism of large extra dimensions. The domination of this constant over the evolution of the universe is only temporary. Due to the interaction of the bulk and the branes, the universe will be in its decelerating expansion phase again in the future, whereby all problems connected with a far future de Sitter universe are resolved
Hofman, C.; Park, J.-S.
1997-01-01
The recent developmen ts in string theory suggest that the space-time coordinates should be generalized to non-comm uting matrices. P ostulating this suggestion as the fun- damen tal geometrical principle, w e form ulate a candidate for covariant second quantized RNS superstrings as a topological
M theory on deformed superspace
Faizal, Mir
2011-11-01
In this paper we will analyze a noncommutative deformation of the Aharony-Bergman-Jafferis-Maldacena (ABJM) theory in N=1 superspace formalism. We will then analyze the Becchi-Rouet-Stora-Tyutin (BRST) and anti-BRST symmetries for this deformed ABJM theory, and its linear as well as nonlinear gauges. We will show that the sum of the gauge fixing term and the ghost term for this deformed ABJM theory can be expressed as a combination of the total BRST and the total anti-BRST variation, in Landau and nonlinear gauges. We will show that in Landau and Curci-Ferrari gauges deformed ABJM theory is invariant under an additional set of symmetry transformations. We will also discuss the effect that the addition of a bare mass term has on this theory.
Division algebra, generalized supersymmetries and octonionic M-theory
International Nuclear Information System (INIS)
Toppan, Francesco
2004-11-01
This is the report of the talk given at the conference 'Number, Time and Relativity', held at the Bauman University, Moscow, August 2004, concerning the recent research activity of the author and his collaborators about the inter-relation of the concepts of division algebras, representations of Clifford algebras, generalized supersymmetries with the introduction of an alternative description of the M-algebra in terms of the non-associative structure of the octonions. (author)
Nonperturbative flipped SU(5) vacua in heterotic M-theory
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Faraggi, Alon E. E-mail: faraggi@thphys.ox.ac.uk; Garavuso, Richard E-mail: garavuso@thphys.ox.ac.uk; Isidro, Jose M. E-mail: isidro@thphys.ox.ac.uk
2002-10-07
The evidence for neutrino masses in atmospheric and solar neutrino experiments provides further support for the embedding of the Standard Model fermions in the chiral 16 SO(10) representation. Such an embedding is afforded by the realistic free fermionic heterotic-string models. In this paper we advance the study of these string models toward a nonperturbative analysis by generalizing the work of Donagi, Pantev, Ovrut and Waldram from the case of G=SU(2n+1) to G=SU(2n) stable holomorphic vector bundles on elliptically fibered Calabi-Yau manifolds with fundamental group Z{sub 2}. We demonstrate existence of G=SU(4) solutions with three generations and SO(10) observable gauge group over Hirzebruch base surface, whereas we show that certain classes of del Pezzo base surface do not admit such solutions. The SO(10) symmetry is broken to SU(5)xU(1) by a Wilson line. The overlap with the realistic free fermionic heterotic-string models is discussed.
On higher-order corrections in M theory
International Nuclear Information System (INIS)
Howe, P.S.; Tsimpis, D.
2003-01-01
A theoretical analysis of higher-order corrections to D=11 supergravity is given in a superspace framework. It is shown that any deformation of D=11 supergravity for which the lowest-dimensional component of the four-form G 4 vanishes is trivial. This implies that the equations of motion of D=11 supergravity are specified by an element of a certain spinorial cohomology group and generalises previous results obtained using spinorial or pure spinor cohomology to the fully non-linear theory. The first deformation of the theory is given by an element of a different spinorial cohomology group with coefficients which are local tensorial functions of the massless supergravity fields. The four-form Bianchi Identities are solved, to first order and at dimension -{1/2}, in the case that the lowest-dimensional component of G 4 is non-zero. Moreover, it is shown how one can calculate the first-order correction to the dimension-zero torsion and thus to the supergravity equations of motion given an explicit expression for this object in terms of the supergravity fields. The version of the theory with both a four-form and a seven-form is discussed in the presence of the five-brane anomaly-cancelling term. It is shown that the supersymmetric completion of this term exists and it is argued that it is the unique anomaly-cancelling invariant at this dimension which is at least quartic in the fields. This implies that the first deformation of the theory is completely determined by the anomaly term from which one can, in principle, read off the corrections to all of the superspace field strength tensors. (author)
Boomerang RG flows in M-theory with intermediate scaling
Donos, Aristomenis; Gauntlett, Jerome P.; Rosen, Christopher; Sosa-Rodriguez, Omar
2017-07-01
We construct novel RG flows of D=11 supergravity that asymptotically approach AdS 4 × S 7 in the UV with deformations that break spatial translations in the dual field theory. In the IR the solutions return to exactly the same AdS 4 × S 7 vacuum, with a renormalisation of relative length scales, and hence we refer to the flows as `boomerang RG flows'. For sufficiently large deformations, on the way to the IR the solutions also approach two distinct intermediate scaling regimes, each with hyperscaling violation. The first regime is Lorentz invariant with dynamical exponent z = 1 while the second has z = 5/2. Neither ofthe two intermediatescaling regimesare associatedwith exact hyperscaling violation solutions of D = 11 supergravity. The RG flow solutions are constructed using the four dimensional N = 2 STU gauged supergravity theory with vanishing gauge fields, but non-vanishing scalar and pseudoscalar fields. In the ABJM dual field theory the flows are driven by spatially modulated deformation parameters for scalar and fermion bilinear operators.
Geometry of extended null supersymmetry in M theory
International Nuclear Information System (INIS)
Conamhna, Oisin A.P. Mac
2006-01-01
For supersymmetric spacetimes in 11 dimensions admitting a null Killing spinor, a set of explicit necessary and sufficient conditions for the existence of any number of arbitrary additional Killing spinors is derived. The necessary and sufficient conditions are comprised of algebraic relationships, linear in the spinorial components, between the spinorial components and their first derivatives, and the components of the spin connection and four-form. The integrability conditions for the Killing spinor equation are also analyzed in detail, to determine which components of the field equations are implied by arbitrary additional supersymmetries and the four-form Bianchi identity. This provides a complete formalism for the systematic and exhaustive investigation of all spacetimes with extended null supersymmetry in 11 dimensions. The formalism is employed to show that the general bosonic solution of 11 dimensional supergravity admitting a G 2 structure defined by four Killing spinors is either locally the direct product of R 1,3 with a seven-manifold of G 2 holonomy, or locally the Freund-Rubin direct product of AdS 4 with a seven-manifold of weak G 2 holonomy. In addition, all supersymmetric spacetimes admitting a (G 2 xR 7 )xR 2 structure are classified
Constrained supermanifolds for AdS M-theory backgrounds
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Fre, Pietro; Grassi, Pietro Antonio
2008-01-01
A long standing problem is the supergauge completion of AdS 4 x ({G/H}) 7 or AdS 5 x ({G/H}) 5 backgrounds which preserve less then maximal supersymmetry. In parallel with the supersolvable realization of the AdS 4 x S 7 background based on κ-symmetry, we develop a technique which amounts to solving the above-mentioned problem in a way useful for pure spinor quantization for supermembranes and superstrings. Instead of gauge fixing some of the superspace coordinates using κ-symmetry, we impose an additional constraint on them reproducing the simplifications of the supersolvable representations. The constraints are quadratic, homogeneous, Sp(4,R)-covariant, and consistent from the quantum point of view in the pure spinor approach. Here we provide the geometrical solution which, in a subsequent work, will be applied to the membrane and the superstring sigma models
Background geometries in string and M-theory
International Nuclear Information System (INIS)
Jeschek, C.
2005-01-01
In this thesis we consider background geometries resulting from string theory compactifications. In particular, we investigate supersymmetric vacuum spaces of supergravity theories and topological twisted sigma models by means of classical and generalised G-structures. In the first part we compactify 11d supergravity on seven-dimensional manifolds due to phenomenological reasons. A certain amount of supersymmetry forces the internal background to admit a classical SU(3)- or G 2 -structure. Especially, in the case that the four-dimensional space is maximally symmetric and four form fluxes are present we calculate the relation to the intrinsic torsion. The second and main part is two-fold. Firstly, we realise that generalised geometries on six-dimensional manifolds are a natural framework to study T-duality and mirror symmetry, in particular if the B-field is non-vanishing. An explicit mirror map is given and we apply this idea to the generalised formulation of a topological twisted sigma model. Implications of mirror symmetry are studied, e.g. observables and topological A- and B-branes. Secondly, we show that seven-dimensional NS-NS backgrounds in type II supergravity theories can be described by generalised G 2 -geometries. A compactification on six manifolds leads to a new structure. We call this geometry a generalised SU(3)-structure. We study the relation between generalised SU(3)- and G 2 -structures on six- and seven-manifolds and generalise the Hitchin-flow equations. Finally, we further develop the generalised SU(3)- and G 2 -structures via a constrained variational principle to incorporate also the remaining physical R-R fields. (Orig.)
On M-theory fourfold vacua with higher curvature terms
International Nuclear Information System (INIS)
Grimm, Thomas W.; Pugh, Tom G.; Weißenbacher, Matthias
2015-01-01
We study solutions to the eleven-dimensional supergravity action, including terms quartic and cubic in the Riemann curvature, that admit an eight-dimensional compact space. The internal background is found to be a conformally Kähler manifold with vanishing first Chern class. The metric solution, however, is non-Ricci-flat even when allowing for a conformal rescaling including the warp factor. This deviation is due to the possible non-harmonicity of the third Chern-form in the leading order Ricci-flat metric. We present a systematic derivation of the background solution by solving the Killing spinor conditions including higher curvature terms. These are translated into first-order differential equations for a globally defined real two-form and complex four-form on the fourfold. We comment on the supersymmetry properties of the described solutions
A brief history of string theory from dual models to M-theory
Rickles, Dean
2014-01-01
During its forty year lifespan, string theory has always had the power to divide, being called both a 'theory of everything' and a 'theory of nothing'. Critics have even questioned whether it qualifies as a scientific theory at all. This book adopts an objective stance, standing back from the question of the truth or falsity of string theory and instead focusing on how it came to be and how it came to occupy its present position in physics. An unexpectedly rich history is revealed, with deep connections to our most well-established physical theories. Fully self-contained and written in a lively fashion, the book will appeal to a wide variety of readers from novice to specialist.
A brief history of string theory. From dual models to M-theory
Energy Technology Data Exchange (ETDEWEB)
Rickles, Dean [Sydney Univ. (Australia). Unit for History and Philosophy of Science
2014-04-01
First monograph devoted to the history of superstring theory. Objective presentation of a controversial area of physics enabling readers to see through the divisive hype and hysteria forming the 'String Wars'. Interweaves conceptual issues with the wider historical development. Reveals string theory's historically close connections with other areas of physics. Self-contained approach brings string theory within the grasp of non-specialists. During its forty year lifespan, string theory has always had the power to divide, being called both a 'theory of everything' and a 'theory of nothing'. Critics have even questioned whether it qualifies as a scientific theory at all. This book adopts an objective stance, standing back from the question of the truth or falsity of string theory and instead focusing on how it came to be and how it came to occupy its present position in physics. An unexpectedly rich history is revealed, with deep connections to our most well-established physical theories. Fully self-contained and written in a lively fashion, the book will appeal to a wide variety of readers from novice to specialist.
M-theory potential from the G{sub 2} Hitchin functional in superspace
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Becker, Katrin; Becker, Melanie; Guha, Sunny; III, William D. Linch [George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy,Texas A& M University,College Station, TX 77843 (United States); Robbins, Daniel [Department of Physics, University at Albany.1400 Washington Ave., Albany, NY 12222 (United States)
2016-12-16
We embed the component fields of eleven-dimensional supergravity into a superspace of the form X×Y where X is the standard 4D, N=1 superspace and Y is a smooth 7-manifold. The eleven-dimensional 3-form gives rise to a tensor hierarchy of superfields gauged by the diffeomorphisms of Y. It contains a natural candidate for a G{sub 2} structure on Y, and being a complex of superforms, defines a superspace Chern-Simons invariant. Adding to this a natural generalization of the Riemannian volume on X×Y and freezing the (superspin-(3/2) and 1) supergravity fields on X, we obtain an approximation to the eleven-dimensional supergravity action that suffices to compute the scalar potential. In this approximation the action is the sum of the superspace Chern-Simons term and a superspace generalization of the Hitchin functional for Y as a G{sub 2}-structure manifold. Integrating out auxiliary fields, we obtain the conditions for unbroken supersymmetry and the scalar potential. The latter reproduces the Einstein-Hilbert term on Y in a form due to Bryant.
From M-theory higher curvature terms to α′ corrections in F-theory
Directory of Open Access Journals (Sweden)
Thomas W. Grimm
2016-02-01
Full Text Available We perform a Kaluza–Klein reduction of eleven-dimensional supergravity on a Calabi–Yau fourfold including terms quartic and cubic in the Riemann curvature and determine the induced corrections to the three-dimensional two-derivative N=2 effective action. We focus on the effective Einstein–Hilbert term and the kinetic terms for vectors. Dualizing the vectors into scalars, we derive the resulting Kähler potential and complex coordinates. The classical expressions for the Kähler coordinates are non-trivially modified by terms containing the third Chern form of the background Calabi–Yau fourfold, while the functional form of the Kähler potential is shown to be uncorrected. We omit terms proportional to the non-harmonic part of the third Chern form. For elliptically fibered Calabi–Yau fourfolds the corrections can be uplifted to a four-dimensional F-theory compactification. We argue that also the four-dimensional N=1 Kähler coordinates receive non-trivial corrections. We find a simple expression for the induced corrections for different Abelian and non-Abelian seven-brane configurations by scanning over many Calabi–Yau fourfolds with resolved singularities. The interpretation of this expression leads us to conjecture that the higher-curvature corrections correspond to α′2 corrections that arise from open strings at the self-intersection of seven-branes.
A brief history of string theory. From dual models to M-theory
International Nuclear Information System (INIS)
Rickles, Dean
2014-01-01
First monograph devoted to the history of superstring theory. Objective presentation of a controversial area of physics enabling readers to see through the divisive hype and hysteria forming the 'String Wars'. Interweaves conceptual issues with the wider historical development. Reveals string theory's historically close connections with other areas of physics. Self-contained approach brings string theory within the grasp of non-specialists. During its forty year lifespan, string theory has always had the power to divide, being called both a 'theory of everything' and a 'theory of nothing'. Critics have even questioned whether it qualifies as a scientific theory at all. This book adopts an objective stance, standing back from the question of the truth or falsity of string theory and instead focusing on how it came to be and how it came to occupy its present position in physics. An unexpectedly rich history is revealed, with deep connections to our most well-established physical theories. Fully self-contained and written in a lively fashion, the book will appeal to a wide variety of readers from novice to specialist.
Connecting String/M Theory to the Electroweak Scale and to LHC Data
Kumar, Piyush
2007-01-01
The Standard Model of particle physics explains (almost) all observed non-gravitational microscopic phenomena but has many open theoretical questions. We are on the threshold of unraveling the mysteries of the Standard Model and discovering its extension. This could be achieved in the near future with the help of many experiments in particle physics and cosmology, the LHC in particular. Assuming that data confirming the existence of new physics beyond the Standard Model is obtained, one is le...
M-theory solutions invariant under D(2,1; γ) + D(2,1;γ)
Energy Technology Data Exchange (ETDEWEB)
Bachas, C. [Laboratoire de Physique Theorique de l' Ecole Normale Superieure Unite mixte (UMR 8549) du CNRS et de l' ENS, Paris (France); D' Hoker, E. [Department of Physics and Astronomy, University of California, Los Angeles, CA (United States); Estes, J. [Blackett Laboratory, Imperial College, London (United Kingdom); Krym, D. [Physics Department, New York City College of Technology, The City University of New York, Brooklyn, NY (United States)
2014-03-06
We simplify and extend the construction of half-BPS solutions to 11-dimensional supergravity, with isometry superalgebra D(2,1;γ) + D(2,1;γ). Their space-time has the form AdS{sub 3} x S{sup 3} x S{sup 3} warped over a Riemann surface Σ. It describes near-horizon geometries of M2 branes ending on, or intersecting with, M5 branes along a common string. The general solution to the BPS equations is specified by a reduced set of data (γ, h, G), where γ is the real parameter of the isometry superalgebra, and h and G are functions on Σ whose differential equations and regularity conditions depend only on the sign of γ. The magnitude of γ enters only through the map of h,G onto the supergravity fields, thereby promoting all solutions into families parametrized by vertical stroke γ vertical stroke. By analyzing the regularity conditions for the supergravity fields, we prove two general theorems: (i) that the only solution with a 2-dimensional CFT dual is AdS{sub 3} x S{sup 3} x S{sup 3} x R {sup 2}, modulo discrete identifications of the flat R {sup 2}, and (ii) that solutions with γ < 0 cannot have more than one asymptotic higher-dimensional AdS region. We classify the allowed singularities of h and G near the boundary of Σ, and identify four local solutions: asymptotic AdS{sub 4}/Z{sub 2} or AdS{sub 7}' regions; highly-curved M5-branes; and a coordinate singularity called the ''cap''. By putting these ''Lego'' pieces together we recover all known global regular solutions with the above symmetry, including the self-dual strings on M5 for γ <0, and the Janus solution for γ > 0, but now promoted to families parametrized by vertical stroke γ vertical stroke. We also construct exactly new regular solutions which are asymptotic to AdS{sub 4}/Z{sub 2} for γ < 0, and conjecture that they are a different superconformal limit of the self-dual string. Finally, we construct exactly γ > 0 solutions with highly curved M5-brane regions, which are the formal continuation of the self-dual string solutions across the decompactification point at γ = 0. (Copyright copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
M-theory solutions invariant under D(2,1; γ) + D(2,1;γ)
International Nuclear Information System (INIS)
Bachas, C.; D'Hoker, E.; Estes, J.; Krym, D.
2014-01-01
We simplify and extend the construction of half-BPS solutions to 11-dimensional supergravity, with isometry superalgebra D(2,1;γ) + D(2,1;γ). Their space-time has the form AdS 3 x S 3 x S 3 warped over a Riemann surface Σ. It describes near-horizon geometries of M2 branes ending on, or intersecting with, M5 branes along a common string. The general solution to the BPS equations is specified by a reduced set of data (γ, h, G), where γ is the real parameter of the isometry superalgebra, and h and G are functions on Σ whose differential equations and regularity conditions depend only on the sign of γ. The magnitude of γ enters only through the map of h,G onto the supergravity fields, thereby promoting all solutions into families parametrized by vertical stroke γ vertical stroke. By analyzing the regularity conditions for the supergravity fields, we prove two general theorems: (i) that the only solution with a 2-dimensional CFT dual is AdS 3 x S 3 x S 3 x R 2 , modulo discrete identifications of the flat R 2 , and (ii) that solutions with γ 4 /Z 2 or AdS 7 ' regions; highly-curved M5-branes; and a coordinate singularity called the ''cap''. By putting these ''Lego'' pieces together we recover all known global regular solutions with the above symmetry, including the self-dual strings on M5 for γ 0, but now promoted to families parametrized by vertical stroke γ vertical stroke. We also construct exactly new regular solutions which are asymptotic to AdS 4 /Z 2 for γ 0 solutions with highly curved M5-brane regions, which are the formal continuation of the self-dual string solutions across the decompactification point at γ = 0. (Copyright copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Rational sphere valued supercocycles in M-theory and type IIA string theory
Czech Academy of Sciences Publication Activity Database
Fiorenza, D.; Schreiber, Urs; Sati, H.
2017-01-01
Roč. 114, April (2017), s. 91-108 ISSN 0393-0440 Institutional support: RVO:67985840 Keywords : homotopy Lie algebras * supersymmetry * branes Subject RIV: BA - General Mathematics OBOR OECD: Applied mathematics Impact factor: 0.819, year: 2016 http://www.sciencedirect.com/science/article/pii/S0393044016303047
From osp(1|32)⊕osp(1|32) to the M-theory superalgebra: a contraction procedure
Energy Technology Data Exchange (ETDEWEB)
Fernández, J. J., E-mail: julio.j.fernandez@hotmail.es; Izquierdo, J. M., E-mail: izquierd@fta.uva.es; Olmo, M. A. del, E-mail: olmo@fta.uva.es [Universidad de Valladolid, Departamento de Física Teórica and IMUVA (Spain)
2017-03-15
We show the impossibility to obtain the D’auria–Fré-type superalgebras that allow for an underlying gauge theoretical structure of D = 11 supergravity from the superalgebra osp(1|32)⊕osp(1|32)−, by means of aWeimar-Woods contraction.
G2-structures for N = 1 supersymmetric AdS4 solutions of M-theory
Grigorian, Sergey
2018-04-01
We study the N = 1 supersymmetric solutions of D = 11 supergravity obtained as a warped product of four-dimensional anti-de Sitter space with a seven-dimensional Riemannian manifold M. Using the octonion bundle structure on M we reformulate the Killing spinor equations in terms of sections of the octonion bundle on M. The solutions then define a single complexified G 2-structure on M or equivalently two real G 2-structures. We then study the torsion of these G 2-structures and the relationships between them.
The M5-brane and non-commutative open strings
Bergshoeff, E.; Berman, D.S.; Schaar, J.P. van der; Sundell, P.
2001-01-01
The M-theory origin of non-commutative open-string theory is examined by investigating the M-theory 5-brane at near critical field strength. In particular, it is argued that the open-membrane metric provides the appropriate moduli when calculating the duality relations between M and II
International Nuclear Information System (INIS)
Acharya, B.S.; Douglas, M.R.
2006-06-01
We present evidence that the number of string/M theory vacua consistent with experiments is finite. We do this both by explicit analysis of infinite sequences of vacua and by applying various mathematical finiteness theorems. (author)
Energy Technology Data Exchange (ETDEWEB)
Ringwald, Andreas
2008-10-15
We illustrate, taking a top-down point of view, how axions and other very weakly interacting sub-eV particles (WISPs) arise in the course of compactification of the extra spatial dimensions in string/M-theory. (orig.)
Partition Functions for Supersymmetric Black Holes
Manschot, Jan
2008-01-01
Dit proefschrift presenteert recente ontdekkingen voor partitiefuncties van vierdimensionale zwarte gaten. Deze partitiefuncties zijn belangrijke instrumenten om de entropie van zwarte gaten microscopisch te verklaren in snaartheorie en M-theorie. De resultaten zijn toegepast in twee centrale
BPS preons and tensionless super-p-brane in generalized superspace
International Nuclear Information System (INIS)
Bandos, Igor A.
2002-08-01
Tensionless super-p-branes in a generalized superspace with additional tensorial central charge coordinates might provide an extended object model for BPS preons, i.e. for hypothetical constituents of M-theory preserving 31 of 32 supersymmeties. (author)
International Nuclear Information System (INIS)
Ringwald, Andreas
2008-10-01
We illustrate, taking a top-down point of view, how axions and other very weakly interacting sub-eV particles (WISPs) arise in the course of compactification of the extra spatial dimensions in string/M-theory. (orig.)
Maximal supergravities and the E10 model
International Nuclear Information System (INIS)
Kleinschmidt, Axel; Nicolai, Hermann
2006-01-01
The maximal rank hyperbolic Kac-Moody algebra e 10 has been conjectured to play a prominent role in the unification of duality symmetries in string and M theory. We review some recent developments supporting this conjecture
A note on flux induced superpotentials in string theory
Energy Technology Data Exchange (ETDEWEB)
Becker, Melanie [Department of Physics, University of Maryland, College Park, MD 20742-4111 (United States)]. E-mail: melanieb@physics.umd.edu; Constantin, Dragos [Department of Physics, University of Maryland, College Park, MD 20742-4111 (United States)
2003-08-01
Non-vanishing fluxes in M-theory and string theory compactifications induce a superpotential in the lower dimensional theory. Gukov has conjectured the explicit form of this superpotential. We check this conjecture for the heterotic string compactified on a Calabi-Yau three-fold as well as for warped M-theory compactifications on Spin(7) holonomy manifolds, by performing a Kaluza-Klein reduction. (author)
A note on flux induced superpotentials in string theory
International Nuclear Information System (INIS)
Becker, Melanie; Constantin, Dragos
2003-01-01
Non-vanishing fluxes in M-theory and string theory compactifications induce a superpotential in the lower dimensional theory. Gukov has conjectured the explicit form of this superpotential. We check this conjecture for the heterotic string compactified on a Calabi-Yau three-fold as well as for warped M-theory compactifications on Spin(7) holonomy manifolds, by performing a Kaluza-Klein reduction. (author)
Phases of N=2 necklace quivers
Directory of Open Access Journals (Sweden)
Antonio Amariti
2018-01-01
Full Text Available We classify the phases of N=2 elliptic models in terms of their global properties i.e. the spectrum of line operators. We show the agreement between the field theory and the M-theory analysis and how the phases form orbits under the action of the S-duality group which corresponds to the mapping class group of the Riemann surface in M-theory.
Notes on Matrix and Micro Strings
Dijkgraaf, Robbert; Verlinde, Herman L.
1998-01-01
We review some recent developments in the study of M-theory compactifications via Matrix theory. In particular we highlight the appearance of IIA strings and their interactions, and explain the unifying role of the M-theory five-brane for describing the spectrum of the T^5 compactification and its duality symmetries. The 5+1-dimensional micro-string theory that lives on the fivebrane world-volume takes a central place in this presentation.
Fivebrane gravitational anomalies
International Nuclear Information System (INIS)
Becker, Katrin; Becker, Melanie
2000-01-01
Freed, Harvey, Minasian and Moore (FHMM) have proposed a mechanism to cancel the gravitational anomaly of the M-theory fivebrane coming from diffeomorphisms acting on the normal bundle. This procedure is based on a modification of the conventional M-theory Chern-Simons term. We apply the FHMM mechanism in the ten-dimensional type IIA theory. We then analyze the relation to the anomaly cancellation mechanism for the type IIA fivebrane proposed by Witten
M(atrix) theory: matrix quantum mechanics as a fundamental theory
International Nuclear Information System (INIS)
Taylor, Washington
2001-01-01
This article reviews the matrix model of M theory. M theory is an 11-dimensional quantum theory of gravity that is believed to underlie all superstring theories. M theory is currently the most plausible candidate for a theory of fundamental physics which reconciles gravity and quantum field theory in a realistic fashion. Evidence for M theory is still only circumstantial -- no complete background-independent formulation of the theory exists as yet. Matrix theory was first developed as a regularized theory of a supersymmetric quantum membrane. More recently, it has appeared in a different guise as the discrete light-cone quantization of M theory in flat space. These two approaches to matrix theory are described in detail and compared. It is shown that matrix theory is a well-defined quantum theory that reduces to a supersymmetric theory of gravity at low energies. Although its fundamental degrees of freedom are essentially pointlike, higher-dimensional fluctuating objects (branes) arise through the non-Abelian structure of the matrix degrees of freedom. The problem of formulating matrix theory in a general space-time background is discussed, and the connections between matrix theory and other related models are reviewed
Supersymmetric Gödel Universes in string theory
DEFF Research Database (Denmark)
Harmark, Troels; Takayanagi, Tadashi
2003-01-01
Supersymmetric backgrounds in string and M-theory of the Gödel Universe type are studied. We find several new Gödel Universes that preserve up to 20 supersymmetries. In particular, we obtain an interesting Gödel Universe in M-theory with 18 supersymmetries which does not seem to be dual to a pp......-wave. We show that not only T-duality but also the type-IIA/M-theory S-duality can give supersymmetric Gödel Universes from pp-waves. We find solutions that can interpolate between Gödel Universes and pp-waves. We also compute the string spectrum on two type IIA Gödel Universes. Furthermore, we obtain...
Is physics in the infinite momentum frame independent of the compactificaction radius?
International Nuclear Information System (INIS)
Gueijosa, A.
1998-01-01
With the aim of clarifying the eleven-dimensional content of matrix theory, we examine the dependence of a theory in the infinite momentum frame (IMF) on the (purely spatial) longitudinal compactification radius R. It is shown that in a point particle theory the generic scattering amplitude becomes independent of R in the IMF. Processes with zero longitudinal momentum transfer are found to be exceptional. The same question is addressed in a theory with extended objects. A one-loop type II string amplitude is shown to be R-independent in the IMF, and to coincide with that of the uncompactified theory. No exceptional processes exist in this case. The possible implications of these results for M theory are discussed. In particular, if amplitudes in M theory are independent of R in the IMF, matrix theory can be rightfully expected (in the N→∞ limit) to describe uncompactified M theory. (orig.)
Infinitely many N=1 dualities from m+1−m=1
Energy Technology Data Exchange (ETDEWEB)
Agarwal, Prarit; Intriligator, Kenneth; Song, Jaewon [Department of Physics, University of California,San Diego, La Jolla, CA 92093 (United States)
2015-10-06
We discuss two infinite classes of 4d supersymmetric theories, T{sub N}{sup (m)} and U{sub N}{sup (m)}, labelled by an arbitrary non-negative integer, m. The T{sub N}{sup (m)} theory arises from the 6d, A{sub N−1} type N=(2,0) theory reduced on a 3-punctured sphere, with normal bundle given by line bundles of degree (m+1,−m); the m=0 case is the N=2 supersymmetric T{sub N} theory. The novelty is the negative-degree line bundle. The U{sub N}{sup (m)} theories likewise arise from the 6d N=(2,0) theory on a 4-punctured sphere, and can be regarded as gluing together two (partially Higgsed) T{sub N}{sup (m)} theories. The T{sub N}{sup (m)} and U{sub N}{sup (m)} theories can be represented, in various duality frames, as quiver gauge theories, built from T{sub N} components via gauging and nilpotent Higgsing. We analyze the RG flow of the U{sub N}{sup (m)} theories, and find that, for all integer m>0, they end up at the same IR SCFT as SU(N) SQCD with 2N flavors and quartic superpotential. The U{sub N}{sup (m)} theories can thus be regarded as an infinite set of UV completions, dual to SQCD with N{sub f}=2N{sub c}. The U{sub N}{sup (m)} duals have different duality frame quiver representations, with 2m+1 gauge nodes.
Les Houches lectures on large N field theories and gravity
International Nuclear Information System (INIS)
Maldacena, J.
2002-01-01
We describe the holographic correspondence between field theories and string/M theory, focusing on the relation between compactifications of string/M theory on Anti-de Sitter spaces and conformal field theories. We review the background for this correspondence and discuss its motivations and the evidence for its correctness. We describe the main results that have been derived from the correspondence in the regime that the field theory is approximated by classical or semiclassical gravity. We focus on the case of the N = 4 supersymmetric gauge theory in four dimensions. (authors)
Goedel, Penrose, anti-Mach: extra supersymmetries of time-dependent plane waves
International Nuclear Information System (INIS)
Blau, Matthias; O'Loughlin, Martin; Meessen, Patrick
2003-01-01
We prove that M-theory plane waves with extra supersymmetries are necessarily homogeneous (but possibly time-dependent), and we show by explicit construction that such time-dependent plane waves can admit extra supersymmetries. To that end we study the Penrose limits of Goedel-like metrics, show that the Penrose limit of the M-theory Goedel metric (with 20 supercharges) is generically a time-dependent homogeneous plane wave of the anti-Mach type, and display the four extra Killings spinors in that case. We conclude with some general remarks on the Killing spinor equations for homogeneous plane waves. (author)
Energy Technology Data Exchange (ETDEWEB)
Douglas, Michael R.; Kachru, Shamit
2006-10-24
We review recent work in which compactifications of string and M theory are constructed in which all scalar fields (moduli) are massive, and supersymmetry is broken with a small positive cosmological constant, features needed to reproduce real world physics. We explain how this work implies that there is a ''landscape'' of string/M theory vacua, perhaps containing many candidates for describing real world physics, and present the arguments for and against this idea. We discuss statistical surveys of the landscape, and the prospects for testable consequences of this picture, such as observable effects of moduli, constraints on early cosmology, and predictions for the scale of supersymmetry breaking.
Goedel, Penrose, anti-Mach: extra supersymmetries of time-dependent plane waves
Energy Technology Data Exchange (ETDEWEB)
Blau, Matthias; O' Loughlin, Martin; Meessen, Patrick [SISSA/ISAS, Via Beirut 2-4, 34014 Trieste (Italy)]. E-mail: meessen@sissa.it
2003-09-01
We prove that M-theory plane waves with extra supersymmetries are necessarily homogeneous (but possibly time-dependent), and we show by explicit construction that such time-dependent plane waves can admit extra supersymmetries. To that end we study the Penrose limits of Goedel-like metrics, show that the Penrose limit of the M-theory Goedel metric (with 20 supercharges) is generically a time-dependent homogeneous plane wave of the anti-Mach type, and display the four extra Killings spinors in that case. We conclude with some general remarks on the Killing spinor equations for homogeneous plane waves. (author)
Nonlattice Simulation for Supersymmetric Gauge Theories in One Dimension
International Nuclear Information System (INIS)
Hanada, Masanori; Nishimura, Jun; Takeuchi, Shingo
2007-01-01
Lattice simulation of supersymmetric gauge theories is not straightforward. In some cases the lack of manifest supersymmetry just necessitates cumbersome fine-tuning, but in the worse cases the chiral and/or Majorana nature of fermions makes it difficult to even formulate an appropriate lattice theory. We propose circumventing all these problems inherent in the lattice approach by adopting a nonlattice approach for one-dimensional supersymmetric gauge theories, which are important in the string or M theory context. In particular, our method can be used to investigate the gauge-gravity duality from first principles, and to simulate M theory based on the matrix theory conjecture
International Nuclear Information System (INIS)
Becker, Katrin; Becker, Melanie; Krause, Axel
2006-01-01
We show that all three conditions for the cosmological relevance of heterotic cosmic strings, the right tension, stability and a production mechanism at the end of inflation, can be met in the strongly coupled M-theory regime. Whereas cosmic strings generated from weakly coupled heterotic strings have the well-known problems posed by Witten in 1985, we show that strings arising from M5-branes wrapped around 4-cycles (divisors) of a Calabi-Yau in heterotic M-theory compactifications solve these problems in an elegant fashion
Craps, Ben; Sethi, Savdeep; Verlinde, Erik
2005-01-01
The light-like linear dilaton background represents a particularly simple time-dependent 1/2 BPS solution of critical type IIA superstring theory in ten dimensions. Its lift to M-theory, as well as its Einstein frame metric, are singular in the sense that the geometry is geodesically incomplete and the Riemann tensor diverges along a light-like subspace of codimension one. We study this background as a model for a big bang type singularity in string theory/M-theory. We construct the dual Matr...
Large N field theories, string theory and gravity
Energy Technology Data Exchange (ETDEWEB)
Maldacena, J [Lyman Laboratory of Physics, Harvard University, Cambridge (United States)
2002-05-15
We describe the holographic correspondence between field theories and string/M theory, focusing on the relation between compactifications of string/ M theory on Anti-de Sitter spaces and conformal field theories. We review the background for this correspondence and discuss its motivations and the evidence for its correctness. We describe the main results that have been derived from the correspondence in the regime that the field theory is approximated by classical or semiclassical gravity. We focus on the case of the N = 4 supersymmetric gauge theory in four dimensions. These lecture notes are based on the Review written by O. Aharony, S. Gubser, J. Maldacena, H. Ooguri and Y. Oz. (author)
BPS quantization of the five-brane
Dijkgraaf, R; Verlinde, Herman L
1997-01-01
We give a unified description of all BPS states of M-theory compactified on T^5 in terms of the five-brane. We compute the mass spectrum and degeneracies and find that the SO(5,5,Z) U-duality symmetry naturally arises as a T-duality by assuming that the world-volume theory of the five-brane itself is described by a string theory. We also consider the compactification on S^1/Z_2 \\times T^4, and give a new explanation for its correspondence with heterotic string theory by exhibiting its dual equivalence to M-theory on K3\\times S^1.
Microscopic Cluster Theory for Exotic Nuclei
International Nuclear Information System (INIS)
Tomaselli, M; Kuehl, T; Ursescu, D; Fritzsche, S
2006-01-01
For a better understanding of the dynamics of complex exotic nuclei it is of crucial importance to develop a practical microscopic theory easy to be applied to a wide range of masses. In this paper we propose to calculate the structure of neutron-rich nuclei within a dynamic model based on the EoM theory
Comments from physicsworld.com
2010-10-01
Oh, God. Yes, the debate about science and religion has kicked off once again, this time thanks to Stephen Hawking and Leonard Mlodinow's new book The Grand Design (2 September "God and the god particle"; 3 September "Talking Hawking and God"; 8 September "M-theory, religion and science funding on the BBC").
Symmetries of string, M- and F-theories
Bergshoeff, Eric; Proeyen, Antoine Van
2001-01-01
The d = 10 type II string theories, d = 11 M-theory and d = 12 F-theory have the same symmetry group. It can be viewed either as a subgroup of a conformal group OSp(1|64) or as a contraction of OSp(1|32). The theories are related by different identifications of their symmetry operators as generators
Bergshoeff, Eric; Proeyen, Antoine Van
2000-01-01
We show that the complete superalgebra of symmetries, including central charges, that underlies F-theories, M-theories and type II string theories in dimensions 12, 11 and 10 of various signatures correspond to rewriting the same OSp(1|32) algebra in different covariant ways. One only has to
Non-linear realizations and bosonic branes
International Nuclear Information System (INIS)
West, P.
2001-01-01
In this very short note, following hep-th/0001216, we express the well known bosonic brane as a non-linear realization. The reader may also consult hep-th/9912226, 0001216 and 0005270 where the branes of M theory are constructed as a non-linear realisation. The automorphisms of the supersymmetry algebra play an essential role. (author)
Five-dimensional gauge theory and compactification on a torus
Haghighat, B.; Vandoren, S.J.G.
2011-01-01
We study five-dimensional minimally supersymmetric gauge theory compactified on a torus down to three dimensions, and its embedding into string/M-theory using geometric engineering. The moduli space on the Coulomb branch is hyperkaehler equipped with a metric with modular transformation properties.
Refined large N duality for knots
DEFF Research Database (Denmark)
Kameyama, Masaya; Nawata, Satoshi
We formulate large N duality of U(N) refined Chern-Simons theory with a torus knot/link in S³. By studying refined BPS states in M-theory, we provide the explicit form of low-energy effective actions of Type IIA string theory with D4-branes on the Ω-background. This form enables us to relate...
Perspectives on string phenomenology
Kane, Gordon; Kumar, Piyush
2015-01-01
The remarkable recent discovery of the Higgs boson at the CERN Large Hadron Collider completed the Standard Model of particle physics and has paved the way for understanding the physics which may lie beyond it. String/M theory has emerged as a broad framework for describing a plethora of diverse physical systems, which includes condensed matter systems, gravitational systems as well as elementary particle physics interactions. If string/M theory is to be considered as a candidate theory of Nature, it must contain an effectively four-dimensional universe among its solutions that is indistinguishable from our own. In these solutions, the extra dimensions of string/M Theory are “compactified” on tiny scales which are often comparable to the Planck length. String phenomenology is the branch of string/M theory that studies such solutions, relates their properties to data, and aims to answer many of the outstanding questions of particle physics beyond the Standard Model. This book contains perspectives on stri...
International Nuclear Information System (INIS)
Johnson, C.V.
1998-01-01
The nature of M-theory on K3 x I, where I is a line interval, is considered, with a view towards formulating a ''matrix theory'' representation of that situation. Various limits of this compactification of M-theory yield a number of well known N=1 six-dimensional compactifications of the heterotic and type I string theories. Geometrical relations between these limits give rise to string/string dualities between some of these compactifications. At a special point in the moduli space of compactifications, this motivates a partial definition of the matrix theory representation of the M-theory on K3 x I as the large N limit of a certain type IA orientifold model probed by a conglomerate of N D-branes. Such a definition in terms of D-branes and orientifold planes is suggestive, but necessarily incomplete, due to the low amount of supersymmetry. It is proposed - following hints from the orientifold model - that the complete matrix theory representation of the K3 x I compactified M-theory is given by the large N limit of compactification - on a suitable ''dual'' surface - of the ''little heterotic string'' N=1 six-dimensional quantum theories. (orig.)
Superspace geometrical realization of the N-extended super Virasoro algebra and its dual
Curto, C.; Gates, S. J., Jr.; Rodgers, V. G. J.
2000-05-01
We derive properties of N-extended /GR super Virasoro algebras. These include adding central extensions, identification of all primary fields and the action of the adjoint representation on its dual. The final result suggest identification with the spectrum of fields in supergravity theories and superstring/M-theory constructed from NSR N-extended supersymmetric /GR Virasoro algebras.
2010-07-06
... Holding S.A.S. G Jonathan B. Murray. G Bunim-Murray Productions. G M Theory Entertainment, Inc. G Mobility.... 27-MAY-10 20100641 G Cerberus Institutional Partners, L.P. G DynCorp International Inc. G DynCorp...
Black hole bound states and their quantization
de Boer, J.
2008-01-01
We briefly review the construction of multi-centered black hole solutions in type IIA string theory. We then discuss a decoupling limit which embeds these solutions in M-theory on AdS(3) x S-2 x CY, and discuss some aspects of their dual CFT interpretation. Finally, we consider the quantization of
Puzzles in quantum gravity : what can black hole microstates teach us about quantum gravity?
El-Showk, S.
2009-01-01
In this thesis we review two independent lines of research directed towards helping us construct a theory of Quantum Gravity. While, in string/M-theory, we already enjoy a potential theory of this type there remain many unanswered foundational questions and missing precepts. By probing the
The gravitational sector of 2d (0,2) F-theory vacua
Energy Technology Data Exchange (ETDEWEB)
Lawrie, Craig [Institut für Theoretische Physik, Ruprecht-Karls-Universität,Philosophenweg 19, Heidelberg, 69120 (Germany); Schäfer-Nameki, Sakura [Mathematical Institute, University of Oxford,Woodstock Road, Oxford, OX2 6GG (United Kingdom); Weigand, Timo [Institut für Theoretische Physik, Ruprecht-Karls-Universität,Philosophenweg 19, Heidelberg, 69120 (Germany)
2017-05-19
F-theory compactifications on Calabi-Yau fivefolds give rise to two-dimensional N=(0,2) supersymmetric field theories coupled to gravity. We explore the dilaton supergravity defined by the moduli sector of such compactifications. The massless moduli spectrum is found by uplifting Type IIB compactifications on Calabi-Yau fourfolds. This spectrum matches expectations from duality with M-theory on the same elliptic fibration. The latter defines an N=2 Supersymmetric Quantum Mechanics related to the 2d (0,2) F-theory supergravity via circle reduction. Using our recent results on the gravitational anomalies of duality twisted D3-branes wrapping curves in Calabi-Yau fivefolds we show that the F-theory spectrum is anomaly free. We match the classical Chern-Simons terms of the M-theory Super Quantum Mechanics to one-loop contributions to the effective action by S{sup 1} reduction of the dual F-theory.
The gravitational sector of 2d (0,2) F-theory vacua
International Nuclear Information System (INIS)
Lawrie, Craig; Schäfer-Nameki, Sakura; Weigand, Timo
2017-01-01
F-theory compactifications on Calabi-Yau fivefolds give rise to two-dimensional N=(0,2) supersymmetric field theories coupled to gravity. We explore the dilaton supergravity defined by the moduli sector of such compactifications. The massless moduli spectrum is found by uplifting Type IIB compactifications on Calabi-Yau fourfolds. This spectrum matches expectations from duality with M-theory on the same elliptic fibration. The latter defines an N=2 Supersymmetric Quantum Mechanics related to the 2d (0,2) F-theory supergravity via circle reduction. Using our recent results on the gravitational anomalies of duality twisted D3-branes wrapping curves in Calabi-Yau fivefolds we show that the F-theory spectrum is anomaly free. We match the classical Chern-Simons terms of the M-theory Super Quantum Mechanics to one-loop contributions to the effective action by S 1 reduction of the dual F-theory.
Is string interaction the origin of quantum mechanics?
Energy Technology Data Exchange (ETDEWEB)
Bars, Itzhak, E-mail: bars@usc.edu; Rychkov, Dmitry
2014-12-12
String theory was developed by demanding consistency with quantum mechanics. In this paper we wish to reverse the reasoning. We pretend that open string field theory is a fully consistent definition of the theory – it is at least a self-consistent sector. Then we find in its structure that the rules of quantum mechanics emerge from the non-commutative nature of the basic string joining/splitting interactions. Thus, rather than assuming the quantum commutation rules among the usual canonical variables we derive them from the physical process of string interactions. Morally we could apply such an argument to M-theory to cover quantum mechanics for all physics. If string or M-theory really underlies all physics, it seems that the door has been opened to an explanation of the origins of quantum mechanics from the physical processes point of view.
Duality symmetry of N=4 Yang-Mills theory on T3
International Nuclear Information System (INIS)
Hacquebord, F.; Verlinde, H.
1997-01-01
We study the spectrum of BPS states in N=4 supersymmetric U(N) Yang-Mills theory. This theory has been proposed to describe M-theory on T 3 in the discrete light-cone formalism. We find that the degeneracy of irreducible BPS bound states in this model exhibits a (partially hidden) SL(5,Z) duality symmetry. Besides the electro-magnetic symmetry, this duality group also contains Nahm-like transformations that interchange the rank N of the gauge group with some of the magnetic or electric fluxes. In the M-theory interpretation, this mapping amounts to a reflection that interchanges the longitudinal direction with one of the transverse directions. (orig.)
Fixing D7-brane positions by F-theory fluxes
International Nuclear Information System (INIS)
Braun, A.P.; Hebecker, A.; Luedeling, C.; Valandro, R.
2009-01-01
To do realistic model building in type IIB supergravity, it is important to understand how to fix D7-brane positions by the choice of fluxes. More generally, F-theory model building requires the understanding of how fluxes determine the singularity structure (and hence gauge group and matter content) of the compactification. We analyse this problem in the simple setting of M-theory on K3xK3. Given a certain flux which is consistent with the F-theory limit, we can explicitly derive the positions at which D7 branes or stacks of D7 branes are stabilised. The analysis is based on a parameterization of the moduli space of type IIB string theory on T 2 /Z 2 (including D7-brane positions) in terms of the periods of integral cycles of M-theory on K3. This allows us, in particular, to select a specific desired gauge group by the choice of flux numbers.
International Nuclear Information System (INIS)
Craps, Ben; Sethi, Savdeep; Verlinde, Erik
2005-01-01
The light-like linear dilaton background represents a particularly simple time-dependent 1/2 BPS solution of critical type-IIA superstring theory in ten dimensions. Its lift to M-theory, as well as its Einstein frame metric, are singular in the sense that the geometry is geodesically incomplete and the Riemann tensor diverges along a light-like subspace of codimension one. We study this background as a model for a big bang type singularity in string theory/M-theory. We construct the dual Matrix theory description in terms of a (1+1)-d supersymmetric Yang-Mills theory on a time-dependent world-sheet given by the Milne orbifold of (1+1)-d Minkowski space. Our model provides a framework in which the physics of the singularity appears to be under control
Energy Technology Data Exchange (ETDEWEB)
Craps, Ben [Instituut voor Theoretische Fysica, Universiteit van Amsterdam, Valckenierstraat 65, 1018 XE Amsterdam (Netherlands); Sethi, Savdeep [Enrico Fermi Institute, University of Chicago, Chicago, IL 60637 (United States); Verlinde, Erik [Instituut voor Theoretische Fysica, Universiteit van Amsterdam, Valckenierstraat 65, 1018 XE Amsterdam (Netherlands)
2005-10-15
The light-like linear dilaton background represents a particularly simple time-dependent 1/2 BPS solution of critical type-IIA superstring theory in ten dimensions. Its lift to M-theory, as well as its Einstein frame metric, are singular in the sense that the geometry is geodesically incomplete and the Riemann tensor diverges along a light-like subspace of codimension one. We study this background as a model for a big bang type singularity in string theory/M-theory. We construct the dual Matrix theory description in terms of a (1+1)-d supersymmetric Yang-Mills theory on a time-dependent world-sheet given by the Milne orbifold of (1+1)-d Minkowski space. Our model provides a framework in which the physics of the singularity appears to be under control.
Some relations between twisted K-theory and E8 gauge theory
International Nuclear Information System (INIS)
Mathai, Varghese; Sati, Hisham
2004-01-01
Recently, Diaconescu, Moore and Witten provided a nontrivial link between K-theory and M-theory, by deriving the partition function of the Ramond-Ramond fields of Type IIA string theory from an E8 gauge theory in eleven dimensions. We give some relations between twisted K-theory and M-theory by adapting the method of Diaconescu-Moore-Witten and Moore-Saulina. In particular, we construct the twisted K-theory torus which defines the partition function, and also discuss the problem from the E8 loop group picture, in which the Dixmier-Douady class is the Neveu-Schwarz field. In the process of doing this, we encounter some mathematics that is new to the physics literature. In particular, the eta differential form, which is the generalization of the eta invariant, arises naturally in this context. We conclude with several open problems in mathematics and string theory. (author)
Godel space from wrapped M2-branes
Czech Academy of Sciences Publication Activity Database
Levi, T.S.; Raeymaekers, Joris; Van den Bleeken, D.; Van Herck, W.; Vercnocke, B.
2010-01-01
Roč. 2010, č. 4 (2010), s. 1-36 ISSN 1126-6708 Grant - others:EUROHORC(XE) EYI/07/E010 Institutional research plan: CEZ:AV0Z10100502 Keywords : D-branes * black holes in string theory * M-theory * AdS-CFT correspondence Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 6.049, year: 2010 http://www.springerlink.com/content/g73p7458588pwv31/
2002 Spring school on superstrings and related matters
Energy Technology Data Exchange (ETDEWEB)
Bachas, C [ENS, Paris (France); Gava, E [INFN, Trieste (Italy); [Abdus Salam ICTP, Trieste (Italy); Maldacena, J [Harvard University, Cambridge (United States); Narain, K S; Randjbar-Daemi, S [Abdus Salam ICTP, Trieste (Italy)
2003-08-15
This CD contains the lecture notes given at the Spring School on Superstrings and related Matters, held at the Abdus Salam International Centre for Theoretical Physics from 18 to 26 March 2002. It contains lectures about M theory, G{sub 2}-manifolds and four dimensional physics, covariant quantization of the superstring, mirror symmetry, strings in flat space and plane waves from N=4 super Yang Mills, phenomenological aspects of D-branes and open string star algebra.
Supersymmetry breaking through confining and dual theory gauge dynamics
International Nuclear Information System (INIS)
Csaki, C.; Massachusetts Inst. of Tech., Cambridge, MA; Randall, L.; Massachusetts Inst. of Tech., Cambridge, MA; Skiba, W.; Massachusetts Inst. of Tech., Cambridge, MA; Leigh, R.G.
1997-01-01
We show that theories in the confining, free magnetic, and conformal phases can break supersymmetry through dynamical effects. To illustrate this, we present theories based on the gauge groups SU(n) x SU(4) x U(1) and SU(n) x SU(5) x U(1) with the field content obtained by decomposing an SU(m) theory with an antisymmetric tensor and m - 4 antifundamentals. (orig.)
Membranes from monopole operators in ABJM theory: Large angular momentum and M-theoretic AdS4/CFT3
International Nuclear Information System (INIS)
Kovacs, Stefano; Sato, Yuki; Shimada, Hidehiko
2014-01-01
We study the duality between M-theory in AdS 4 ×S 7 /ℤ k and the ABJM N=6 Chern–Simons-matter theory with gauge group U(N)×U(N) and level k, taking N large and k of order 1. In this M-theoretic regime the lack of an explicit formulation of M-theory in AdS 4 ×S 7 /ℤ k makes the gravity side difficult, while the CFT is strongly coupled and the planar approximation is not applicable. We focus on states on the gravity side with large angular momentum J≫1 associated with a single plane of rotation in S 7 and identify their dual operators in the CFT. We show that natural approximation schemes arise on both sides thanks to the presence of the small parameter 1/J. On the AdS side, we use the matrix model of M-theory on the maximally supersymmetric pp-wave background with matrices of size J/k. A perturbative treatment of this matrix model provides a good approximation to M-theory in AdS 4 ×S 7 /ℤ k when N 1/3 ≪J≪N 1/2 . On the CFT side, we study the theory on S 2 ×ℝ with magnetic flux J/k. A Born–Oppenheimer-type expansion arises naturally for large J in spite of the theory being strongly coupled. The energy spectra on the two sides agree at leading order. This provides a non-trivial test of the AdS 4 /CFT 3 correspondence including near-BPS observables associated with membrane degrees of freedom, thus verifying the duality beyond the previously studied sectors corresponding to either BPS observables or the type IIA string regime
Comments on AdS2 solutions of D = 11 supergravity
International Nuclear Information System (INIS)
Kim, Nakwoo; Park, Jong-Dae
2006-01-01
We study the supersymmetric solutions of 11-dimensional supergravity with a factor of AdS 2 made of M2-branes. Such solutions can provide gravity duals of superconformal quantum mechanics, or through double Wick rotation, the generic bubbling geometry of M-theory which are 1/16-BPS. We show that, when the internal manifold is compact, it should take the form of a warped U(1)-fibration over an 8-dimensional Kaehler space
Dualities and signatures of G++-invariant theories
International Nuclear Information System (INIS)
Buyl, Sophie de; Houart, Laurent; Tabti, Nassiba
2005-01-01
The G ++ -content of the formulation of gravity and M-theories as very-extended Kac-Moody invariant theories is further analysed. The different exotic phases of all the G ++ B -theories, which admit exact solutions describing intersecting branes smeared in all directions but one, are derived. This is achieved by analysing for all G ++ the signatures which are related to the conventional one (1,D-1) by 'dualities' generated by the Weyl reflections
International Nuclear Information System (INIS)
Douglas, Michael R.; Nekrasov, Nikita A.
2001-01-01
This article reviews the generalization of field theory to space-time with noncommuting coordinates, starting with the basics and covering most of the active directions of research. Such theories are now known to emerge from limits of M theory and string theory and to describe quantum Hall states. In the last few years they have been studied intensively, and many qualitatively new phenomena have been discovered, on both the classical and the quantum level
Generalised structures for N=1 AdS backgrounds
Energy Technology Data Exchange (ETDEWEB)
Coimbra, André [Institut für Theoretische Physik & Center for Quantum Engineering and Spacetime Research,Leibniz Universität Hannover,Appelstraße 2, 30167 Hannover (Germany); Strickland-Constable, Charles [Institut de physique théorique, Université Paris Saclay, CEA, CNRS, Orme des Merisiers, F-91191 Gif-sur-Yvette (France)
2016-11-16
We expand upon a claim made in a recent paper [http://arxiv.org/abs/1411.5721] that generic minimally supersymmetric AdS backgrounds of warped flux compactifications of Type II and M theory can be understood as satisfying a straightforward weak integrability condition in the language of E{sub d(d)}×ℝ{sup +} generalised geometry. Namely, they are spaces admitting a generalised G-structure set by the Killing spinor and with constant singlet generalised intrinsic torsion.
On the interplay between string theory and field theory
International Nuclear Information System (INIS)
Brunner, I.
1998-01-01
In this thesis, we have discussed various aspects of branes in string theory and M-theory. In chapter 2 we were able to construct six-dimensional chiral interacting eld theories from Hanany-Witten like brane setups. The field theory requirement that the anomalies cancel was reproduced by RR-charge conservation in the brane setup. The data of the Hanany-Witten setup, which consists of brane positions, was mapped to instanton data. The orbifold construction can be extended to D and E type singularities. In chapter 3 we discussed a matrix conjecture, which claims that M-theory in the light cone gauge is described by the quantum mechanics of D0 branes. Toroidal compactifications of M-theory have a description in terms of super Yang-Mills theory an the dual torus. For more than three compactified dimensions, more degrees of freedom have to be added. In some sense, the philosophy in this chapter is orthogonal to the previous chapter: Here, we want to get M-theory results from eld theory considerations, whereas in the previous chapter we obtained eld theory results by embedding the theories in string theory. Our main focus was on the compactification on T 6 , which leads to complications. Here, the Matrix model is again given by an eleven dimensional theory, not by a lower dimensional field theory. Other problems and possible resolutions of Matrix theory are discussed at the end of chapter 3. In the last chapter we considered M- and F-theory compactifications on Calabi-Yau fourfolds. After explaining some basics of fourfolds, we showed that the web of fourfolds is connected by singular transitions. The two manifolds which are connected by the transition are different resolutions of the same singular manifold. The resolution of the singularities can lead to a certain type of divisors, which lead to non-perturbative superpotentials, when branes wrap them. The vacua connected by the transitions can be physically very different. (orig.)
Branes wrapped on coassociative cycles
International Nuclear Information System (INIS)
Hernandez, Rafael
2001-06-01
We obtain a supergravity solution arising when D6-branes are wrapped on coassociative four-cycles of constant curvature in seven manifolds of G 2 holonomy. The solutions preserve two supercharges and thus represent supergravity duals of three dimensional Yang-Mills with N=1 supersymmetry. When uplifted to eleven dimensions our solution describes M-theory on the background of an eight manifold with Spin(7) holonomy. (author)
Boucher, Jill
2012-01-01
In this review, the history of the theory of mind (ToM) theory of autistic spectrum disorder (ASD) is outlined (in which ToM is indexed by success on false belief tasks), and the explanatory power and psychological causes of impaired ToM in ASD are critically discussed. It is concluded that impaired ToM by itself has only limited explanatory…
Non-renormalisation theorems in string theory
International Nuclear Information System (INIS)
Vanhove, P.
2007-10-01
In this thesis we describe various non renormalisation theorems for the string effective action. These results are derived in the context of the M theory conjecture allowing to connect the four gravitons string theory S matrix elements with that of eleven dimensional supergravity. These theorems imply that N = 8 supergravity theory has the same UV behaviour as the N = 4 supersymmetric Yang Mills theory at least up to three loops, and could be UV finite in four dimensions. (author)
2002 Spring school on superstrings and related matters
International Nuclear Information System (INIS)
Bachas, C.; Gava, E.; Maldacena, J.; Narain, K.S.; Randjbar-Daemi, S.
2003-01-01
This CD contains the lecture notes given at the Spring School on Superstrings and related Matters, held at the Abdus Salam International Centre for Theoretical Physics from 18 to 26 March 2002. It contains lectures about M theory, G 2 -manifolds and four dimensional physics, covariant quantization of the superstring, mirror symmetry, strings in flat space and plane waves from N=4 super Yang Mills, phenomenological aspects of D-branes and open string star algebra
Steven Hawking to visit Texas A&M in spring
Xavier, D
2002-01-01
Stephen Hawking will visit Texas A&M University from Feb. 24 to March 21 2003 to participate in the inaugural meeting of the George P. and Cynthia W. Mitchell Institute for Fundamental Physics. This institute will bring several of the world's top physicists to A&M for a month-long exploration of the latest ideas on topics ranging from superstrings to M-theory and supergravity (1/2 page).
GENERALIZED p-FORMS ELECTRODYNAMICS IN CLIFFORD SPACES
Castro, C
2003-01-01
Using Clifford algebraic methods we describe how to generalize Maxwell theory of Electrodynamics asociated with ordinary point-charges to a generalized Maxwell theory in Clifford spaces involving extended-charges and p-forms of arbitrary rank. Clifford algebras contain the appropriate algebraic-geometric features to implement the principle of polydimensional transformations (branes of different dimensionality are rotated into each other) that could possibly lead to a proper formulation of string and M theory.
Automatic bounding estimation in modified NLMS algorithm
International Nuclear Information System (INIS)
Shahtalebi, K.; Doost-Hoseini, A.M.
2002-01-01
Modified Normalized Least Mean Square algorithm, which is a sign form of Nlm based on set-membership (S M) theory in the class of optimal bounding ellipsoid (OBE) algorithms, requires a priori knowledge of error bounds that is unknown in most applications. In a special but popular case of measurement noise, a simple algorithm has been proposed. With some simulation examples the performance of algorithm is compared with Modified Normalized Least Mean Square
A stringy origin of M2 brane Chern-Simons theories
International Nuclear Information System (INIS)
Aganagic, Mina
2010-01-01
We show that string duality relates M-theory on a local Calabi-Yau fourfold singularity X 4 to type IIA string theory on a Calabi-Yau threefold X 3 fibered over a real line, with RR 2-form fluxes turned on. The RR flux encodes how the M-theory circle is fibered over the IIA geometry. The theories on N D2 branes probing X 3 are the well-known quiver theories with N=2 supersymmetry in three dimensions. We show that turning on fluxes, and fibering the X 3 over a direction transverse to the branes, corresponds to turning on N=2 Chern-Simons couplings. String duality implies that, in the strong coupling limit, the N D2 branes on X 3 in this background become N M2 branes on X 4 . This provides a string theory derivation for the recently conjectured description of the M2 brane theories on Calabi-Yau fourfolds in terms of N=2 quiver Chern-Simons theories. We also provide a new N=2 Chern-Simons theory dual to AdS 4 xQ 1,1,1 . Type IIA/M-theory duality also relates IIA string theory on X 3 with only the RR fluxes turned on, to M-theory on a G 2 holonomy manifold. We show that this implies that the N M2 branes probing the G 2 manifold are described by the quiver Chern-Simons theory originating from the D2 branes probing X 3 , except that now Chern-Simons terms preserve only N=1 supersymmetry in three dimensions.
Unlocking the axion-dilaton in 5D supergravity
Czech Academy of Sciences Publication Activity Database
Raeymaekers, Joris; Van den Bleeken, D.
2014-01-01
Roč. 11, Nov (2014), s. 1-54 ISSN 1029-8479 R&D Projects: GA ČR(CZ) GA14-31689S Institutional support: RVO:68378271 Keywords : supergravity models * d-branes * m-theory * black holes in string theory Subject RIV: BE - Theoretical Physics Impact factor: 6.111, year: 2014 http://link.springer.com/article/10.1007%2FJHEP11%282014%29029
Microstate solutions from black hole deconstruction
Czech Academy of Sciences Publication Activity Database
Raeymaekers, Joris; Van den Bleeken, D.
2015-01-01
Roč. 2015, č. 12 (2015), s. 095 ISSN 1029-8479 R&D Projects: GA ČR(CZ) GA14-31689S Grant - others:AV ČR(CZ) TUB-14-03 Program:Bilaterální spolupráce Institutional support: RVO:68378271 Keywords : back holes in string theory * AdS-CFT correspondence * D-branes * M-theory Subject RIV: BE - Theoretical Physics Impact factor: 6.023, year: 2015
Dijkgraaf, R; Verlinde, Herman L
1997-01-01
Via compactification on a circle, the matrix model of M-theory proposed by Banks et al suggests a concrete identification between the large N limit of two-dimensional N=8 supersymmetric Yang-Mills theory and type IIA string theory. In this paper we collect evidence that supports this identification. We explicitly identify the perturbative string states and their interactions, and describe the appearance of D-particle and D-membrane states.
International Nuclear Information System (INIS)
Di Vecchia, Paolo
1997-01-01
In discussing the construction of a consistent theory of quantum gravity unified with the gauge interactions we are naturally led to a string theory. We review its properties and the five consistent supersymmetric string theories in ten dimensions. We finally discuss the evidence that these theories are actually special limits of a unique 11-dimensional theory, called M-theory, and a recent conjecture for its explicit formulation as a supersymmetric Matrix theory
The exceptional generalised geometry of supersymmetric AdS flux backgrounds
Energy Technology Data Exchange (ETDEWEB)
Ashmore, Anthony [Merton College, University of Oxford,Merton Street, Oxford, OX1 4JD (United Kingdom); Mathematical Institute, University of Oxford, Andrew Wiles Building,Woodstock Road, Oxford, OX2 6GG (United Kingdom); Petrini, Michela [Sorbonne Université, UPMC Paris 06, UMR 7589,LPTHE, 75005 Paris (France); Waldram, Daniel [Department of Physics, Imperial College London,Prince Consort Road, London, SW7 2AZ (United Kingdom)
2016-12-29
We analyse generic AdS flux backgrounds preserving eight supercharges in D=4 and D=5 dimensions using exceptional generalised geometry. We show that they are described by a pair of globally defined, generalised structures, identical to those that appear for flat flux backgrounds but with different integrability conditions. We give a number of explicit examples of such “exceptional Sasaki-Einstein” backgrounds in type IIB supergravity and M-theory. In particular, we give the complete analysis of the generic AdS{sub 5} M-theory backgrounds. We also briefly discuss the structure of the moduli space of solutions. In all cases, one structure defines a “generalised Reeb vector” that generates a Killing symmetry of the background corresponding to the R-symmetry of the dual field theory, and in addition encodes the generic contact structures that appear in the D=4 M-theory and D=5 type IIB cases. Finally, we investigate the relation between generalised structures and quantities in the dual field theory, showing that the central charge and R-charge of BPS wrapped-brane states are both encoded by the generalised Reeb vector, as well as discussing how volume minimisation (the dual of a- and F-maximisation) is encoded.
N =1 supergravitational heterotic galileons
Deen, Rehan; Ovrut, Burt
2017-11-01
Heterotic M -theory consists of a five-dimensional manifold of the form S 1 / Z 2 × M 4. It has been shown that one of the two orbifold planes, the "observable" sector, can have a low energy particle spectrum which is precisely the N = 1 super-symmetric standard model with three right-handed neutrino chiral supermultiplets. The other orbifold plane constitutes a "hidden" sector which, since its communication with the observable sector is suppressed, will be ignored in this paper. However, the finite fifth-dimension allows for the existence of three-brane solitons which, in order to render the vacuum anomaly free, must appear. That is, heterotic M -theory provides a natural framework for brane-world cosmological scenarios coupled to realistic particle physics. The complete worldvolume action of such three-branes is unknown. Here, treating these solitons as probe branes, we construct their scalar worldvolume Lagrangian as a derivative expansion of the heterotic DBI action. In analogy with similar calculations in the M 5 and AdS 5 context, this leads to the construction of "heterotic Galileons". However, realistic vacua of heterotic M -theory are necessarily N = 1 supersymmetric in four dimensions. Hence, we proceed to supersymmetrize the three-brane worldvolume action, first in flat superspace and then extend the results to N = 1 supergravity. Such a worldvolume action may lead to interesting cosmology, such as "bouncing" universe models, by allowing for the violation of the Null Energy Condition (NEC).
Physics of F-theory compactifications without section
International Nuclear Information System (INIS)
Anderson, Lara B.; García-Etxebarria, Iñaki; Grimm, Thomas W.; Keitel, Jan
2014-01-01
We study the physics of F-theory compactifications on genus-one fibrations without section by using an M-theory dual description. The five-dimensional action obtained by considering M-theory on a Calabi-Yau threefold is compared with a six-dimensional F-theory effective action reduced on an additional circle. We propose that the six-dimensional effective action of these setups admits geometrically massive U(1) vectors with a charged hypermultiplet spectrum. The absence of a section induces NS-NS and R-R three-form fluxes in F-theory that are non-trivially supported along the circle and induce a shift-gauging of certain axions with respect to the Kaluza-Klein vector. In the five-dimensional effective theory the Kaluza-Klein vector and the massive U(1)s combine into a linear combination that is massless. This U(1) is identified with the massless U(1) corresponding to the multi-section of the Calabi-Yau threefold in M-theory. We confirm this interpretation by computing the one-loop Chern-Simons terms for the massless vectors of the five-dimensional setup by integrating out all massive states. A closed formula is found that accounts for the hypermultiplets charged under the massive U(1)s.
Aspects of U-duality in matrix theory
International Nuclear Information System (INIS)
Blau, M.; O'Loughlin, M.
1997-12-01
We explore various aspects of implementing the full M-theory U-duality group E d+1 , and thus Lorentz invariance, in the finite N matrix theory (DLCQ of M-theory) describing toroidal IIA-compactifications on d-tori: (1) We generalize the analysis of Elitzur et al. (hep-th/9707217) from E d to E d+1 and identify the highest weight states unifying the momentum and flux E d -multiplets into one E d+1 -orbit, (2) We identify the new symmetries, in particular the Weyl group symmetry associated to the (d+1)'th node of the E d+1 Dynkin diagram, with Nahm-duality-like symmetries (N-duality) exchanging the rank N of the matrix theory gauge group with other (electric, magnetic, ...) quantum numbers. (3) We describe the action of N-duality on BPS bound states, thus making testable predictions for the Lorentz invariance of matrix theory. (4) We discuss the problems that arise in the matrix theory limit for BPS states with no top-dimensional branes, i.e. configurations with N = 0. (5) We show that N-duality maps the matrix theory SYM picture to the matrix string picture and argue that, for d even, the latter should be thought of as an M-theory membrane description (which appears to be well defined even for d > 5). (6) We find a compact and unified expression for a U-duality invariant of E d+1 for all d and show that in d = 5,6 it reduces to the black hole entropy cubic E 6 - and quartic E 7 -invariants respectively. (7) Finally, we describe some of the solitonic states in d = 6,7 and give an example (a 'rolled-up' Taub-NUT 6-brane) of a configuration exhibiting the unusual 1/g 3 s -behaviour. (author)
Gorbatov, Elie
In the first part of the dissertation we study noncommutative field theories at finite temperature. We find evidence for winding states and observe the existence of a transition to a new phase where there is a reduction of the degrees of freedom in the non-planar sector of the theory. We emphasize that such a transition is generic and insensitive to the particulars of the UV definition of the theory. In the second part we investigate some aspects of M-theory compactifications on orbifolds. The heterotic E8 x E 8 string compactified on T4/ ZN has gauge group G x G˜ with massless states in the twisted sector charged under both factors. In the dual M-theory description on T4/ ZN x S1/Z 2 the two groups do not communicate with each other since they reside on the boundary of the eleven dimensional spacetime. This leads to a conundrum for the twisted states of the perturbative heterotic string for there does not seem to be local degrees of freedom which carry charges under both G and G˜. We propose a resolution of this apparent paradox by nonperturbative states in M-theory. In support of our argument we review the consideration of six-dimensional gauge couplings and verify the local anomaly cancellation. In order to understand the dynamical properties of these states we deform the orbifold geometry, find an equivalent string theory background, and brane engineer the low energy six-dimensional field theories. In the process we encounter many exotic and surprising phenomena which are intrinsically M-theoretic and completely invisible to the perturbative observer.
Quantum aspects of black objects in string theory
Energy Technology Data Exchange (ETDEWEB)
Hyakutake, Yoshifumi [College of Science, Ibaraki University,Bunkyo 2-1-1, Mito, Ibaraki 310-8512 (Japan)
2017-01-17
One of important directions in superstring theory is to reveal the quantum nature of black hole. In this paper we embed Schwarzschild black hole into superstring theory or M-theory, which we call a smeared black hole, and resolve quantum corrections to it. Furthermore we boost the smeared black hole along the 11th direction and construct a smeared quantum black 0-brane in 10 dimensions. Quantum aspects of the thermodynamic for these black objects are investigated in detail. We also discuss radiations of a string and a D0-brane from the smeared quantum black 0-brane.
Neumann and Neumann-Rosochatius integrable systems from membranes on AdS4 x S7
International Nuclear Information System (INIS)
Bozhilov, Plamen
2007-01-01
It is known that large class of classical string solutions in the type IIB AdS 5 x S 5 background is related to the Neumann and Neumann-Rosochatius integrable systems, including spiky strings and giant magnons. It is also interesting if these integrable systems can be associated with some membrane configurations in M-theory. We show here that this is indeed the case by presenting explicitly several types of membrane embedding in AdS 4 x S 7 with the searched properties
N =1 Lagrangians for generalized Argyres-Douglas theories
Agarwal, Prarit; Sciarappa, Antonio; Song, Jaewon
2017-10-01
We find N = 1 Lagrangian gauge theories that flow to generalized ArgyresDouglas theories with N = 2 supersymmetry. We find that certain SU quiver gauge theories flow to generalized Argyres-Douglas theories of type ( A k-1 , A mk-1) and ( I m,km , S). We also find quiver gauge theories of SO/Sp gauge groups flowing to the ( A 2 m-1 , D 2 mk+1), ( A 2 m , D 2 m( k-1)+ k ) and D m(2 k + 2) m(2 k + 2) [ m] theories.
N = 4 Superconformal Chern-Simons theories with hyper and twisted hyper multiplets
International Nuclear Information System (INIS)
Hosomichi, Kazuo; Lee, Ki-Myeong; Lee, Sungjay; Lee, Sangmin; Park, Jaemo
2008-01-01
We extend the N = 4 superconformal Chern-Simons theories of Gaiotto and Witten to those with additional twisted hyper-multiplets. The new theories are generically linear quiver gauge theories with the two types of hyper-multiplets alternating between gauge groups. Our construction includes the Bagger-Lambert model of SO(4) gauge group. A family of abelian theories are identified with those proposed earlier in the context of the M-crystal model for M2-branes probing (C 2 /Z n ) 2 orbifolds. Possible extension with non-abelian BF couplings and string/M-theory realization are briefly discussed.
Gadde, Abhijit; Haghighat, Babak; Kim, Joonho; Kim, Seok; Lockhart, Guglielmo; Vafa, Cumrun
2018-02-01
We consider bound states of strings which arise in 6d (1,0) SCFTs that are realized in F-theory in terms of linear chains of spheres with negative self-intersections 1,2, and 4. These include the strings associated to N small E 8 instantons, as well as the ones associated to M5 branes probing A and D type singularities in M-theory or D5 branes probing ADE singularities in Type IIB string theory. We find that these bound states of strings admit (0,4) supersymmetric quiver descriptions and show how one can compute their elliptic genera.
On the interplay between string theory and field theory
Energy Technology Data Exchange (ETDEWEB)
Brunner, I.
1998-07-08
In this thesis, we have discussed various aspects of branes in string theory and M-theory. In chapter 2 we were able to construct six-dimensional chiral interacting eld theories from Hanany-Witten like brane setups. The field theory requirement that the anomalies cancel was reproduced by RR-charge conservation in the brane setup. The data of the Hanany-Witten setup, which consists of brane positions, was mapped to instanton data. The orbifold construction can be extended to D and E type singularities. In chapter 3 we discussed a matrix conjecture, which claims that M-theory in the light cone gauge is described by the quantum mechanics of D0 branes. Toroidal compactifications of M-theory have a description in terms of super Yang-Mills theory an the dual torus. For more than three compactified dimensions, more degrees of freedom have to be added. In some sense, the philosophy in this chapter is orthogonal to the previous chapter: Here, we want to get M-theory results from eld theory considerations, whereas in the previous chapter we obtained eld theory results by embedding the theories in string theory. Our main focus was on the compactification on T{sup 6}, which leads to complications. Here, the Matrix model is again given by an eleven dimensional theory, not by a lower dimensional field theory. Other problems and possible resolutions of Matrix theory are discussed at the end of chapter 3. In the last chapter we considered M- and F-theory compactifications on Calabi-Yau fourfolds. After explaining some basics of fourfolds, we showed that the web of fourfolds is connected by singular transitions. The two manifolds which are connected by the transition are different resolutions of the same singular manifold. The resolution of the singularities can lead to a certain type of divisors, which lead to non-perturbative superpotentials, when branes wrap them. The vacua connected by the transitions can be physically very different. (orig.)
G(2) Holonomy Spaces from Invariant Three-Forms
Brandhuber, Andreas
2001-01-01
We construct several new G(2) holonomy metrics that play an important role in recent studies of geometrical transitions in compactifications of M-theory to four dimensions. In type IIA string theory these metrics correspond to D6 branes wrapped on the three-cycle of the deformed conifold and the resolved conifold with two-form RR flux on the blown-up two-sphere, which are related by a conifold transition. We also study a G(2) metric that is related in type IIA to the line bundle over S^2 x S^...
Suppressing proton decay in theories with localised fermions
International Nuclear Information System (INIS)
Acharya, B.S.; Valandro, R.
2005-12-01
We calculate the contribution to the proton decay amplitude from Kaluza-Klein lepto-quarks in theories with extra dimensions, localised fermions and gauge fields which propagate in the bulk. Such models naturally occur within the context of M theory. In SU(5) models we show that carefully including all such modes gives a distinctive pattern of decays through various channels including a strong suppression of decays into neutrinos or right handed positrons. By contrast there is no such suppression for SO(10). (author)
Pure spinors, free differential algebras, and the supermembrane
International Nuclear Information System (INIS)
Fre, Pietro; Grassi, Pietro Antonio
2007-01-01
The Lagrangian formalism for the supermembrane in any 11d supergravity background is constructed in the pure spinor framework. Our gauge-fixed action is manifestly BRST, supersymmetric, and 3d Lorentz invariant. The relation between the Free Differential Algebras (FDA) underlying 11d supergravity and the BRST symmetry of the membrane action is exploited. The 'gauge-fixing' has a natural interpretation as the variation of the Chevalley cohomology class needed for the extension of 11d super-Poincare superalgebra to M-theory FDA. We study the solution of the pure spinor constraints in full detail
Pure spinors, free differential algebras, and the supermembrane
Energy Technology Data Exchange (ETDEWEB)
Fre, Pietro [Dipartimento di Fisica Teorica, Universita di Torino, and INFN-Sezione di Torino, Via P. Giuria 1, I-10125 Turin (Italy); Grassi, Pietro Antonio [Centro Studi e Ricerche E. Fermi, Compendio Viminale, I-00184 Rome (Italy) and DISTA, Universita del Piemonte Orientale, and INFN-Sezione di Torino, Via Bellini 25/G, Alessandria 15100 (Italy) and CERN, Theory Unit, CH-1211 Geneva 23 (Switzerland)]. E-mail: pgrassi@insti.physics.sunysb.edu
2007-02-12
The Lagrangian formalism for the supermembrane in any 11d supergravity background is constructed in the pure spinor framework. Our gauge-fixed action is manifestly BRST, supersymmetric, and 3d Lorentz invariant. The relation between the Free Differential Algebras (FDA) underlying 11d supergravity and the BRST symmetry of the membrane action is exploited. The 'gauge-fixing' has a natural interpretation as the variation of the Chevalley cohomology class needed for the extension of 11d super-Poincare superalgebra to M-theory FDA. We study the solution of the pure spinor constraints in full detail.
International Nuclear Information System (INIS)
Bachas, Constantin; Bunster, Claudio; Henneaux, Marc
2009-01-01
In three spacetime dimensions the world volume of a magnetic source is a single point, an event. We make the event dynamical by regarding it as the imprint of a flux-carrying particle impinging from an extra dimension. This can be generalized to higher spacetime dimensions and to extended events. We exhibit universal observable consequences of the existence of events and argue that events are as important as particles or branes. We explain how events arise on the world volume of membranes in M theory, and in a Josephson junction in superconductivity.
Int. Solvay Inst., Brussels
2012-01-01
The Modave Summer School in Mathematical Physics is organized by enthusiastic PhD students from Belgian universities (ULB, VUB, KUL) for other young PhD students or post-docs from all around Europe. The main goal is to present introductory and pedagogical lectures on theoretical physic topics, ranging from basics to research subjects. The topics presented in these proceedings of the Eighth edition are: Introduction to Conformal Field Theories, Thermodynamics of String Gas, Higher Spin Theory, Introduction to Universality and Renormalisation Group Techniques and Duality Symmetric Approaches to String and M-theory
On the number of elementary particles in a resolution dependent fractal spacetime
International Nuclear Information System (INIS)
He Jihuan
2007-01-01
We reconsider the fundamental question regarding the number of elementary particles in a minimally extended standard model. The main conclusion is that since the dimension of E-infinity spacetime is resolution dependent, then the number of elementary particles is also resolution dependent. For D = 10 of superstrings, D = 11 of M theory and D = 12 of F theory one finds N(SM) equal to (6)(10) = 60 (6)(11) = 66 and (6)(12) = 72 particles, respectively. This is in perfect agreement with prediction made previously by Mohamed Saladin El-Naschie and Marek-Crnjac
Tops as building blocks for G 2 manifolds
Braun, Andreas P.
2017-10-01
A large number of examples of compact G 2 manifolds, relevant to supersymmetric compactifications of M-Theory to four dimensions, can be constructed by forming a twisted connected sum of two building blocks times a circle. These building blocks, which are appropriate K3-fibred threefolds, are shown to have a natural and elegant construction in terms of tops, which parallels the construction of Calabi-Yau manifolds via reflexive polytopes. In particular, this enables us to prove combinatorial formulas for the Hodge numbers and other relevant topological data.
Les Houches 1999 Summer School, Session 71 : The Primordial Universe
Schäffer, R; Silk, J; David, F
2000-01-01
This book reviews the interconnection of cosmology and particle physics over the last decade. It provides introductory courses in supersymmetry, superstring and M-theory, responding to an increasing interest to evaluate the cosmological consequences of these theories. Based on a series of extended courses providing an introduction to the physics of the very early universe, in the light of the most recent advances in our understanding of the fundamental interactions, it reviews all the classical issues (inflation, primordial fluctuations, dark matter, baryogenesis), but also introduces the most
Geometric Algebra Techniques in Flux Compactifications
International Nuclear Information System (INIS)
Coman, Ioana Alexandra; Lazaroiu, Calin Iuliu; Babalic, Elena Mirela
2016-01-01
We study “constrained generalized Killing (s)pinors,” which characterize supersymmetric flux compactifications of supergravity theories. Using geometric algebra techniques, we give conceptually clear and computationally effective methods for translating supersymmetry conditions into differential and algebraic constraints on collections of differential forms. In particular, we give a synthetic description of Fierz identities, which are an important ingredient of such problems. As an application, we show how our approach can be used to efficiently treat N=1 compactification of M-theory on eight manifolds and prove that we recover results previously obtained in the literature.
E{sub 6} Yukawa couplings in F-theory as D-brane instanton effects
Energy Technology Data Exchange (ETDEWEB)
Collinucci, Andrés [Physique Théorique et Mathématique and International Solvay Institutes,Université Libre de Bruxelles, C.P. 231, 1050 Bruxelles (Belgium); García-Etxebarria, Iñaki [Max Planck Institute for Physics,Föhringer Ring 6, 80805 Munich (Germany)
2017-03-29
At weak coupling the neighborhood of a E{sub 6} Yukawa point in SU(5) GUT F-theory models is described by a non-resolvable orientifold of the conifold. We explicitly show, first directly in IIB and then via a mirror symmetry argument, that in this limit the E{sub 6} Yukawa coupling is better described as coming from the non-perturbative contribution of a euclidean D1-brane wrapping the non-resolvable cycle. We also discuss how the M-theory description interpolates between the weak and strong coupling viewpoints.
篠原, 弘章; 森田, 真美; シノハラ, ヒロフミ; モリタ, マミ; Shinohara, Hirofumi; Morita, Mami
1989-01-01
This study aims at investigating the influence of parental leadership behaviors toward their social powers to children. The subjects were 294 school children of 5th and 6th grade in an elementary school. Parental leadership behaviors were categorized into the following four types; PM-type, P-type, M-type and pm-type, all of which are based on P-M theory. Our findings were as follows: 1) According to Direct Varimax Method, the following 5 factors were found out. : i. e. reward power, coercive ...
Early universe cosmology and tests of fundamental physics
International Nuclear Information System (INIS)
Albrecht, Andreas; Frieman, Joshua A.; Trodden, Mark
2002-01-01
This is the report of the Working Group on Early Universe Cosmology and tests of Fundamental Physics, group P4.8 of the of the Snowmass 2001 conference. Here we summarize the impressive array of advances that have taken place in this field, and identify opportunities for even greater progress in the future. Topics include Dark Energy, Cosmic Acceleration, Inflation, Phase Transitions, Baryogenesis, and String/M-theory Cosmology. The introductory section gives an executive summary with six key open questions on which we can expect to make significant progress
Energy Technology Data Exchange (ETDEWEB)
Lleo Morilla, A
1963-07-01
The interactions of a 29 MeV 3{sup H}e particles beam on a Cl{sub 4}C vapour target have been studied using the photographic method. differential cross-sections for the Cl({sup 3}He, {sup 3}He)Cl elastic scattering and {sup 1}2C({sup 3}He, {alpha}){sup 1}1C pick-up reaction are shown; the corresponding angular distributions in the centre-of-mass system have been compared with the predictions of optical model and A.B.M. theories. (Author) 21 refs.
Donagi, Ron; Pantev, Tony; Waldram, Dan; Donagi, Ron; Ovrut, Burt; Pantev, Tony; Waldram, Dan
2002-01-01
We describe a family of genus one fibered Calabi-Yau threefolds with fundamental group ${\\mathbb Z}/2$. On each Calabi-Yau $Z$ in the family we exhibit a positive dimensional family of Mumford stable bundles whose symmetry group is the Standard Model group $SU(3)\\times SU(2)\\times U(1)$ and which have $c_{3} = 6$. We also show that for each bundle $V$ in our family, $c_{2}(Z) - c_{2}(V)$ is the class of an effective curve on $Z$. These conditions ensure that $Z$ and $V$ can be used for a phenomenologically relevant compactification of Heterotic M-theory.
Massive IIA string theory and Matrix theory compactification
International Nuclear Information System (INIS)
Lowe, David A.; Nastase, Horatiu; Ramgoolam, Sanjaye
2003-01-01
We propose a Matrix theory approach to Romans' massive Type IIA supergravity. It is obtained by applying the procedure of Matrix theory compactifications to Hull's proposal of the massive Type IIA string theory as M-theory on a twisted torus. The resulting Matrix theory is a super-Yang-Mills theory on large N three-branes with a space-dependent noncommutativity parameter, which is also independently derived by a T-duality approach. We give evidence showing that the energies of a class of physical excitations of the super-Yang-Mills theory show the correct symmetry expected from massive Type IIA string theory in a lightcone quantization
International Nuclear Information System (INIS)
Kleinschmidt, Axel; Nicolai, Hermann
2006-01-01
We construct simple exact solutions to the E 10 /K(E 10 ) coset model by exploiting its integrability. Using the known correspondences with the bosonic sectors of maximal supergravity theories, these exact solutions translate into exact cosmological solutions. In this way, we are able to recover some recently discovered solutions of M-theory exhibiting phases of accelerated expansion, or, equivalently, S-brane solutions, and thereby accommodate such solutions within the E 10 /K(E 10 ) model. We also discuss the situation regarding solutions with non-vanishing (constant) curvature of the internal manifold
Geometric transitions, flops and non-Kahler manifolds: I
International Nuclear Information System (INIS)
Becker, Melanie; Dasgupta, Keshav; Knauf, Anke; Tatar, Radu
2004-01-01
We construct a duality cycle which provides a complete supergravity description of geometric transitions in type II theories via a flop in M-theory. This cycle connects the different supergravity descriptions before and after the geometric transitions. Our construction reproduces many of the known phenomena studied earlier in the literature and allows us to describe some new and interesting aspects in a simple and elegant fashion. A precise supergravity description of new torsional manifolds that appear on the type IIA side with branes and fluxes and the corresponding geometric transition are obtained. A local description of new G2 manifolds that are circle fibrations over non-Kahler manifolds is presented
5D Yang-Mills instantons from ABJM Monopoles
Lambert, N.; Papageorgakis, C.
2012-01-01
In the presence of a background supergravity flux, N M2-branes will expand via the Myers effect into M5-branes wrapped on a fuzzy three-sphere. In previous work the fluctuations of the M2-branes were shown to be described by the five-dimensional Yang-Mills gauge theory associated to D4-branes. We show that the ABJM prescription for eleven-dimensional momentum in terms of magnetic flux lifts to an instanton flux of the effective five-dimensional Yang-Mills theory on the sphere, giving an M-theory interpretation for these instantons.
Anomaly cancellation and smooth non-Kahler solutions in heterotic string theory
International Nuclear Information System (INIS)
Becker, Katrin; Becker, Melanie; Fu Jixiang; Tseng, L.-S.; Yau, S.-T.
2006-01-01
We show that six-dimensional backgrounds that are T 2 bundle over a Calabi-Yau two-fold base are consistent smooth solutions of heterotic flux compactifications. We emphasize the importance of the anomaly cancellation condition which can only be satisfied if the base is K3 while a T 4 base is excluded. The conditions imposed by anomaly cancellation for the T 2 bundle structure, the dilaton field, and the holomorphic stable bundles are analyzed and the solutions determined. Applying duality, we check the consistency of the anomaly cancellation constraints with those for flux backgrounds of M-theory on eight-manifolds
Interaction of a 29 MeV 3He particle beam with a Cl4C vapour target
International Nuclear Information System (INIS)
Lleo Morilla, A.
1963-01-01
The interactions of a 29 MeV 3 H e particles beam on a Cl 4 C vapour target have been studied using the photographic method. differential cross-sections for the Cl( 3 He, 3 He)Cl elastic scattering and 1 2C( 3 He, α) 1 1C pick-up reaction are shown; the corresponding angular distributions in the centre-of-mass system have been compared with the predictions of optical model and A.B.M. theories. (Author) 21 refs
International Nuclear Information System (INIS)
Figueroa-O’Farrill, José; Ungureanu, Mara
2016-01-01
Motivated by the search for new gravity duals to M2 branes with N>4 supersymmetry — equivalently, M-theory backgrounds with Killing superalgebra osp(N|4) for N>4 — we classify (except for a small gap) homogeneous M-theory backgrounds with symmetry Lie algebra so(n)⊕so(3,2) for n=5,6,7. We find that there are no new backgrounds with n=6,7 but we do find a number of new (to us) backgrounds with n=5. All backgrounds are metrically products of the form AdS 4 ×P 7 , with P riemannian and homogeneous under the action of SO(5), or S 4 ×Q 7 with Q lorentzian and homogeneous under the action of SO(3,2). At least one of the new backgrounds is supersymmetric (albeit with only N=2) and we show that it can be constructed from a supersymmetric Freund-Rubin background via a Wick rotation. Two of the new backgrounds have only been approximated numerically.
Brane Inflation, Solitons and Cosmological Solutions: I
Energy Technology Data Exchange (ETDEWEB)
Chen, P.
2005-01-25
In this paper we study various cosmological solutions for a D3/D7 system directly from M-theory with fluxes and M2-branes. In M-theory, these solutions exist only if we incorporate higher derivative corrections from the curvatures as well as G-fluxes. We take these corrections into account and study a number of toy cosmologies, including one with a novel background for the D3/D7 system whose supergravity solution can be completely determined. Our new background preserves all the good properties of the original model and opens up avenues to investigate cosmological effects from wrapped branes and brane-antibrane annihilation, to name a few. We also discuss in some detail semilocal defects with higher global symmetries, for example exceptional ones, that occur in a slightly different regime of our D3/D7 model. We show that the D3/D7 system does have the required ingredients to realize these configurations as non-topological solitons of the theory. These constructions also allow us to give a physical meaning to the existence of certain underlying homogeneous quaternionic Kahler manifolds.
Cosmic strings in f(R,L{sub m}) gravity
Energy Technology Data Exchange (ETDEWEB)
Harko, Tiberiu [University College London, Department of Mathematics, London (United Kingdom); Lake, Matthew J. [Naresuan University, The Institute for Fundamental Study, ' ' The Tah Poe Academia Institute' ' , Phitsanulok (Thailand); Ministry of Education, Thailand Center of Excellence in Physics, Bangkok (Thailand)
2015-02-01
We consider Kasner-type static, cylindrically symmetric interior string solutions in the f(R,L{sub m}) theory of modified gravity. The physical properties of the string are described by an anisotropic energy-momentum tensor satisfying the condition T{sub t}{sup t} = T{sub z}{sup z}; that is, the energy density of the string along the z-axis is equal to minus the string tension. As a first step in our study we obtain the gravitational field equations in the f(R,L{sub m}) theory for a general static, cylindrically symmetric metric, and then for a Kasner-type metric, in which the metric tensor components have a power law dependence on the radial coordinate r. String solutions in two particular modified gravity models are investigated in detail. The first is the so-called ''exponential'' modified gravity, in which the gravitational action is proportional to the exponential of the sum of the Ricci scalar and matter Lagrangian, and the second is the ''self-consistent model'', obtained by explicitly determining the gravitational action from the field equations under the assumption of a power law dependent matter Lagrangian. In each case, the thermodynamic parameters of the string, as well as the precise form of the matter Lagrangian, are explicitly obtained. (orig.)
Covariantized matrix theory for D-particles
Energy Technology Data Exchange (ETDEWEB)
Yoneya, Tamiaki [Institute of Physics, The University of Tokyo,3-8-1 Komaba, Meguro-ku, Tokyo 153-8902 (Japan); School of Graduate Studies, The Open University of Japan,2-11 Wakaba, Mihama-ku, Chiba 261-8586 (Japan)
2016-06-09
We reformulate the Matrix theory of D-particles in a manifestly Lorentz-covariant fashion in the sense of 11 dimesnional flat Minkowski space-time, from the viewpoint of the so-called DLCQ interpretation of the light-front Matrix theory. The theory is characterized by various symmetry properties including higher gauge symmetries, which contain the usual SU(N) symmetry as a special case and are extended from the structure naturally appearing in association with a discretized version of Nambu’s 3-bracket. The theory is scale invariant, and the emergence of the 11 dimensional gravitational length, or M-theory scale, is interpreted as a consequence of a breaking of the scaling symmetry through a super-selection rule. In the light-front gauge with the DLCQ compactification of 11 dimensions, the theory reduces to the usual light-front formulation. In the time-like gauge with the ordinary M-theory spatial compactification, it reduces to a non-Abelian Born-Infeld-like theory, which in the limit of large N becomes equivalent with the original BFSS theory.
Grand Unification as a Bridge Between String Theory and Phenomenology
Energy Technology Data Exchange (ETDEWEB)
Pati, Jogesh C.
2006-06-09
In the first part of the talk, I explain what empirical evidence points to the need for having an effective grand unification-like symmetry possessing the symmetry SU(4)-color in 4D. If one assumes the premises of a future predictive theory including gravity--be it string/M theory or a reincarnation--this evidence then suggests that such a theory should lead to an effective grand unification-like symmetry as above in 4D, near the string-GUT-scale, rather than the standard model symmetry. Advantages of an effective supersymmetric G(224) = SU(2){sub L} x SU(2){sub R} x SU(4){sup c} or SO(10) symmetry in 4D in explaining (1) observed neutrino oscillations, (2) baryogenesis via leptogenesis, and (3) certain fermion mass-relations are noted. And certain distinguishing tests of a SUSY G(224) or SO(10)-framework involving CP and flavor violations (as in {mu} {yields} e{gamma}, {tau} {yields} {mu}{gamma}, edm's of the neutron and the electron) as well as proton decay are briefly mentioned. Recalling some of the successes we have had in our understanding of nature so far, and the current difficulties of string/M theory as regards the large multiplicity of string vacua, some comments are made on the traditional goal of understanding vis a vis the recently evolved view of landscape and anthropism.
Gerbes, M5-brane anomalies and E8 gauge theory
International Nuclear Information System (INIS)
Aschieri, Paolo; Jurco, Branislav
2004-01-01
Abelian gerbes and twisted bundles describe the topology of the NS 3-form gauge field strength H. We review how they have been usefully applied to study and resolve global anomalies in open string theory. Abelian 2-gerbes and twisted nonabelian gerbes describe the topology of the 4-form field strength G of M-theory. We show that twisted nonabelian gerbes are relevant in the study and resolution of global anomalies of multiple coinciding M5-branes. Global anomalies for one M5-brane have been studied by Witten and by Diaconescu, Freed and Moore. The structure and the differential geometry of twisted nonabelian gerbes (i.e. modules for 2-gerbes) is defined and studied. The nonabelian 2-form gauge potential living on multiple coinciding M5-branes arises as curving (curvature) of twisted nonabelian gerbes. The nonabelian group is in general Ω-tildeE 8 , the central extension of the E 8 loop group. The twist is in general necessary to cancel global anomalies due to the non-triviality of the 11-dimensional 4-form field strength G and due to the possible torsion present in the cycles the M5-branes wrap. Our description of M5-branes global anomalies leads to the D4-branes one upon compactification of M-theory to Type IIA theory. (author)
Gerbes, M5-brane anomalies and E{sub 8} gauge theory
Energy Technology Data Exchange (ETDEWEB)
Aschieri, Paolo [Dipartimento di Scienze e Tecnologie Avanzate, Universita del Piemonte Orientale and INFN, Via Bellini 25/G, 15100 Alessandria (Italy) and Max-Planck-Institut fuer Physik, Foehringer Ring 6, D-80805, Munich (Germany) and Sektion Physik, Universitaet Muenchen, Theresienstr. 37, D-80333 Munich (Germany)]. E-mail: aschieri@theorie.physik.uni-muenchen.de; Jurco, Branislav [Max-Planck-Institut fuer Physik, Foeringer Ring 6, D-80805, Munich (Germany); Sektion Physik, Universitaet Muechen, Theresienstr. 37, D-80333 Munich (Germany)
2004-10-01
Abelian gerbes and twisted bundles describe the topology of the NS 3-form gauge field strength H. We review how they have been usefully applied to study and resolve global anomalies in open string theory. Abelian 2-gerbes and twisted nonabelian gerbes describe the topology of the 4-form field strength G of M-theory. We show that twisted nonabelian gerbes are relevant in the study and resolution of global anomalies of multiple coinciding M5-branes. Global anomalies for one M5-brane have been studied by Witten and by Diaconescu, Freed and Moore. The structure and the differential geometry of twisted nonabelian gerbes (i.e. modules for 2-gerbes) is defined and studied. The nonabelian 2-form gauge potential living on multiple coinciding M5-branes arises as curving (curvature) of twisted nonabelian gerbes. The nonabelian group is in general {omega}-tildeE{sub 8}, the central extension of the E{sub 8} loop group. The twist is in general necessary to cancel global anomalies due to the non-triviality of the 11-dimensional 4-form field strength G and due to the possible torsion present in the cycles the M5-branes wrap. Our description of M5-branes global anomalies leads to the D4-branes one upon compactification of M-theory to Type IIA theory. (author)
Gerbes, M5-Brane Anomalies and E8 Gauge Theory
Aschieri, Paolo; Jurco, Branislav
2004-10-01
Abelian gerbes and twisted bundles describe the topology of the NS 3-form gauge field strength H. We review how they have been usefully applied to study and resolve global anomalies in open string theory. Abelian 2-gerbes and twisted nonabelian gerbes describe the topology of the 4-form field strength G of M-theory. We show that twisted nonabelian gerbes are relevant in the study and resolution of global anomalies of multiple coinciding M5-branes. Global anomalies for one M5-brane have been studied by Witten and by Diaconescu, Freed and Moore. The structure and the differential geometry of twisted nonabelian gerbes (i.e. modules for 2-gerbes) is defined and studied. The nonabelian 2-form gauge potential living on multiple coinciding M5-branes arises as curving (curvature) of twisted nonabelian gerbes. The nonabelian group is in general tilde OmegaE8, the central extension of the E8 loop group. The twist is in general necessary to cancel global anomalies due to the nontriviality of the 11-dimensional 4-form field strength G and due to the possible torsion present in the cycles the M5-branes wrap. Our description of M5-branes global anomalies leads to the D4-branes one upon compactification of M-theory to Type IIA theory.
F-theory vacua with $\\mathbb Z_3$ gauge symmetry
Cvetič, Mirjam; Klevers, Denis; Piragua, Hernan; Poretschkin, Maximilian
2015-01-01
Discrete gauge groups naturally arise in F-theory compactifications on genus-one fibered Calabi-Yau manifolds. Such geometries appear in families that are parameterized by the Tate-Shafarevich group of the genus-one fibration. While the F-theory compactification on any element of this family gives rise to the same physics, the corresponding M-theory compactifications on these geometries differ and are obtained by a fluxed circle reduction of the former. In this note, we focus on an element of order three in the Tate-Shafarevich group of the general cubic. We discuss how the different M-theory vacua and the associated discrete gauge groups can be obtained by Higgsing of a pair of five-dimensional U(1) symmetries. The Higgs fields arise from vanishing cycles in $I_2$-fibers that appear at certain codimension two loci in the base. We explicitly identify all three curves that give rise to the corresponding Higgs fields. In this analysis the investigation of different resolved phases of the underlying geometry pla...
Seven-Disk Manifold, alpha-attractors and B-modes
Ferrara, Sergio
2016-01-01
Cosmological alpha-attractor models in \\cN=1 supergravity are based on hyperbolic geometry of a Poincar\\'e disk with the radius square {\\cal R}^2=3\\alpha. The predictions for the B-modes, r\\approx 3\\alpha {4\\over N^2}, depend on moduli space geometry and are robust for a rather general class of potentials. Here we notice that starting with M-theory compactified on a 7-manifold with G_2 holonomy, with a special choice of Betti numbers, one can obtain d=4 \\cN=1 supergravity with rank 7 scalar coset \\Big[{SL(2)\\over SO(2)}\\Big]^7. In a model where these 7 unit size Poincar\\'e disks have identified moduli one finds that 3 alpha =7. Assuming that the moduli space geometry of the phenomenological models is inherited from this version of M-theory, one would predict r \\approx 10^{-2} for 53 e-foldings. We also describe the related maximal supergravity and M/string theory models leading to preferred values 3 alpha =1,2,3,4,5,6,7.
Energy Technology Data Exchange (ETDEWEB)
Lee, Kanghoon [Quantum Universe Center, Korea Institute for Advanced Study, Seoul (Korea, Republic of); Strickland-Constable, Charles [Institut de Physique Theorique, Universite Paris Saclay, CEA, CNRS, Gif-sur-Yvette (France); Waldram, Daniel [Department of Physics, Imperial College London (United Kingdom); Berkeley Center for Theoretical Physics, University of California, Berkeley, CA (United States)
2017-10-15
We discuss the possible realisation in string/M theory of the recently discovered family of four-dimensional maximal SO(8) gauged supergravities, and of an analogous family of seven-dimensional half-maximal SO(4) gauged supergravities. We first prove a no-go theorem that neither class of gaugings can be realised via a compactification that is locally described by ten- or eleven-dimensional supergravity. In the language of Double Field Theory and its M theory analogue, this implies that the section condition must be violated. Introducing the minimal number of additional coordinates possible, we then show that the standard S{sup 3} and S{sup 7} compactifications of ten- and eleven-dimensional supergravity admit a new class of section-violating generalised frames with a generalised Lie derivative algebra that reproduces the embedding tensor of the SO(4) and SO(8) gaugings respectively. The physical meaning, if any, of these constructions is unclear. They highlight a number of the issues that arise when attempting to apply the formalism of Double Field Theory to non-toroidal backgrounds. Using a naive brane charge quantisation to determine the periodicities of the additional coordinates restricts the SO(4) gaugings to an infinite discrete set and excludes all the SO(8) gaugings other than the standard one. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Energy Technology Data Exchange (ETDEWEB)
Figueroa-O’Farrill, José [School of Mathematics and Maxwell Institute for Mathematical Sciences,The University of Edinburgh,James Clerk Maxwell Building, The King’s Buildings, Peter Guthrie Tait Road,Edinburgh EH9 3FD, Scotland (United Kingdom); Ungureanu, Mara [Humboldt-Universität zu Berlin, Institut für Mathematik,Unter den Linden 6, 10099 Berlin (Germany)
2016-01-25
Motivated by the search for new gravity duals to M2 branes with N>4 supersymmetry — equivalently, M-theory backgrounds with Killing superalgebra osp(N|4) for N>4 — we classify (except for a small gap) homogeneous M-theory backgrounds with symmetry Lie algebra so(n)⊕so(3,2) for n=5,6,7. We find that there are no new backgrounds with n=6,7 but we do find a number of new (to us) backgrounds with n=5. All backgrounds are metrically products of the form AdS{sub 4}×P{sup 7}, with P riemannian and homogeneous under the action of SO(5), or S{sup 4}×Q{sup 7} with Q lorentzian and homogeneous under the action of SO(3,2). At least one of the new backgrounds is supersymmetric (albeit with only N=2) and we show that it can be constructed from a supersymmetric Freund-Rubin background via a Wick rotation. Two of the new backgrounds have only been approximated numerically.
Membrane solitons in eight-dimensional hyper-Kaehler backgrounds
Energy Technology Data Exchange (ETDEWEB)
Portugues, Ruben [DAMTP, Centre for Mathematical Sciences, Cambridge University, Wilberforce Road, Cambridge CB3 0WA (United Kingdom)]. E-mail: R.Portugues@damtp.cam.ac.uk
2004-03-01
We derive the BPS equations satisfied by lump solitons in (2+1)-dimensional sigma models with toric 8-dimensional hyper-Kaehler (HK{sub 8}) target spaces and check they preserve 1/2 of the supersymmetry. We show how these solitons are realised in M theory as M2-branes wrapping holomorphic 2-cycles in the E{sup 1,2} x HK{sub 8} background. Using the {kappa}-symmetry of a probe M2-brane in this background we determine the supersymmetry they preserve, and note that there is a discrepancy in the fraction of supersymmetry preserved by these solitons as viewed from the low energy effective sigma model description of the M2-brane dynamics or the full M theory. Toric HK{sub 8} manifolds are dual to a Hanany-Witten setup of D3-branes suspended between 5-branes. In this picture the lumps correspond to vortices of the three dimensional N = 3 or N = 4 theory. (author)
The N=1 effective action of F-theory compactifications
International Nuclear Information System (INIS)
Grimm, Thomas W.
2011-01-01
The four-dimensional N=1 effective action of F-theory compactified on a Calabi-Yau fourfold is studied by lifting a three-dimensional M-theory compactification. The lift is performed by using T-duality realized via a Legendre transform on the level of the effective action, and the application of vector-scalar duality in three dimensions. The leading order Kaehler potential and gauge-kinetic coupling functions are determined. In these compactifications two sources of gauge theories are present. Space-time filling non-Abelian seven-branes arise at the singularities of the elliptic fibration of the fourfold. Their couplings are included by resolving the singular fourfold. Generically a U(1) r gauge theory arises from the R-R bulk sector if the base of the elliptically fibered Calabi-Yau fourfold supports 2r harmonic three-forms. The gauge coupling functions depend holomorphically on the complex structure moduli of the fourfold, comprising closed and open string degrees of freedom. The four-dimensional electro-magnetic duality is studied in the three-dimensional effective theory obtained after M-theory compactification. A discussion of matter couplings transforming in the adjoint of the seven-brane gauge group is included.
International Nuclear Information System (INIS)
Lee, Kanghoon; Strickland-Constable, Charles; Waldram, Daniel
2017-01-01
We discuss the possible realisation in string/M theory of the recently discovered family of four-dimensional maximal SO(8) gauged supergravities, and of an analogous family of seven-dimensional half-maximal SO(4) gauged supergravities. We first prove a no-go theorem that neither class of gaugings can be realised via a compactification that is locally described by ten- or eleven-dimensional supergravity. In the language of Double Field Theory and its M theory analogue, this implies that the section condition must be violated. Introducing the minimal number of additional coordinates possible, we then show that the standard S 3 and S 7 compactifications of ten- and eleven-dimensional supergravity admit a new class of section-violating generalised frames with a generalised Lie derivative algebra that reproduces the embedding tensor of the SO(4) and SO(8) gaugings respectively. The physical meaning, if any, of these constructions is unclear. They highlight a number of the issues that arise when attempting to apply the formalism of Double Field Theory to non-toroidal backgrounds. Using a naive brane charge quantisation to determine the periodicities of the additional coordinates restricts the SO(4) gaugings to an infinite discrete set and excludes all the SO(8) gaugings other than the standard one. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Multiple fibrations in Calabi-Yau geometry and string dualities
Energy Technology Data Exchange (ETDEWEB)
Anderson, Lara B.; Gao, Xin; Gray, James; Lee, Seung-Joo [Physics Department, Virginia Tech,Robeson Hall, Blacksburg, VA 24061 (United States)
2016-10-19
In this work we explore the physics associated to Calabi-Yau (CY) n-folds that can be described as a fibration in more than one way. Beginning with F-theory vacua in various dimensions, we consider limits/dualities with M-theory, type IIA, and heterotic string theories. Our results include many M-/F-theory correspondences in which distinct F-theory vacua — associated to different elliptic fibrations of the same CY n-fold — give rise to the same M-theory limit in one dimension lower. Examples include 5-dimensional correspondences between 6-dimensional theories with Abelian, non-Abelian and superconformal structure, as well as examples of higher rank Mordell-Weil geometries. In addition, in the context of heterotic/F-theory duality, we investigate the role played by multiple K3- and elliptic fibrations in known and novel string dualities in 8-, 6- and 4-dimensional theories. Here we systematically summarize nested fibration structures and comment on the roles they play in T-duality, mirror symmetry, and 4-dimensional compactifications of F-theory with G-flux. This investigation of duality structures is made possible by geometric tools developed in a companion paper http://arxiv.org/abs/1608.07554.
On membrane interactions and a three-dimensional analog of Riemann surfaces
Energy Technology Data Exchange (ETDEWEB)
Kovacs, Stefano [Dublin Institute for Advanced Studies, 10 Burlington Road, Dublin 4 (Ireland); ICTP South American Institute for Fundamental Research, IFT-UNESP,São Paulo, SP 01440-070 (Brazil); Sato, Yuki [National Institute for Theoretical Physics, School of Physics and Mandelstam Institute for Theoretical Physics, University of the Witwartersrand,Wits 2050 (South Africa); Shimada, Hidehiko [Okayama Institute for Quantum Physics,Okayama (Japan)
2016-02-08
Membranes in M-theory are expected to interact via splitting and joining processes. We study these effects in the pp-wave matrix model, in which they are associated with transitions between states in sectors built on vacua with different numbers of membranes. Transition amplitudes between such states receive contributions from BPS instanton configurations interpolating between the different vacua. Various properties of the moduli space of BPS instantons are known, but there are very few known examples of explicit solutions. We present a new approach to the construction of instanton solutions interpolating between states containing arbitrary numbers of membranes, based on a continuum approximation valid for matrices of large size. The proposed scheme uses functions on a two-dimensional space to approximate matrices and it relies on the same ideas behind the matrix regularisation of membrane degrees of freedom in M-theory. We show that the BPS instanton equations have a continuum counterpart which can be mapped to the three-dimensional Laplace equation through a sequence of changes of variables. A description of configurations corresponding to membrane splitting/joining processes can be given in terms of solutions to the Laplace equation in a three-dimensional analog of a Riemann surface, consisting of multiple copies of ℝ{sup 3} connected via a generalisation of branch cuts. We discuss various general features of our proposal and we also present explicit analytic solutions.
Supersymmetry of noncompact MQCD-like membrane instantons and heat kernel asymptotics
International Nuclear Information System (INIS)
Belani, Kanishka; Kaura, Payal; Misra, Aalok
2006-01-01
We perform a heat kernel asymptotics analysis of the nonperturbative superpotential obtained from wrapping of an M2-brane around a supersymmetric noncompact three-fold embedded in a (noncompact) G 2 -manifold as obtained, the three-fold being the one relevant to domain walls in Witten's MQCD, in the limit of small 'ζ', a complex constant that appears in the Riemann surfaces relevant to defining the boundary conditions for the domain wall in MQCD. The MQCD-like configuration is interpretable, for small but non-zero ζ as a noncompact/'large open membrane instanton, and for vanishing ζ, as the type IIA D0-brane (for vanishing M-theory circle radius). We find that the eta-function Seeley de-Witt coefficients vanish, and we get a perfect match between the zeta-function Seeley de-Witt coefficients (up to terms quadratic in ζ) between the Dirac-type operator and one of the two Laplace-type operators figuring in the superpotential. Given the dissimilar forms of the bosonic and the square of the fermionic operators, this is an extremely nontrivial check, from a spectral analysis point of view, of the expected residual supersymmetry for the nonperturbative configurations in M-theory considered in this work
F-theory and 2d (0,2) theories
Energy Technology Data Exchange (ETDEWEB)
Schäfer-Nameki, Sakura [Department of Mathematics, King’s College London, The Strand, London WC2R 2LS (United Kingdom); Weigand, Timo [Institut für Theoretische Physik, Ruprecht-Karls-Universität,Philosophenweg 19, 69120 Heidelberg (Germany)
2016-05-11
F-theory compactified on singular, elliptically fibered Calabi-Yau five-folds gives rise to two-dimensional gauge theories preserving N=(0,2) supersymmetry. In this paper we initiate the study of such compactifications and determine the dictionary between the geometric data of the elliptic fibration and the 2d gauge theory such as the matter content in terms of (0,2) superfields and their supersymmetric couplings. We study this setup both from a gauge-theoretic point of view, in terms of the partially twisted 7-brane theory, and provide a global geometric description based on the structure of the elliptic fibration and its singularities. Global consistency conditions are determined and checked against the dual M-theory compactification to one dimension. This includes a discussion of gauge anomalies, the structure of the Green-Schwarz terms and the Chern-Simons couplings in the dual M-theory supersymmetric quantum mechanics. Furthermore, by interpreting the resulting 2d (0,2) theories as heterotic worldsheet theories, we propose a correspondence between the geometric data of elliptically fibered Calabi-Yau five-folds and the target space of a heterotic gauged linear sigma-model (GLSM). In particular the correspondence between the Landau-Ginsburg and sigma-model phase of a 2d (0,2) GLSM is realized via different T-branes or gluing data in F-theory.
Classical propagation of strings across a big crunch/big bang singularity
International Nuclear Information System (INIS)
Niz, Gustavo; Turok, Neil
2007-01-01
One of the simplest time-dependent solutions of M theory consists of nine-dimensional Euclidean space times 1+1-dimensional compactified Milne space-time. With a further modding out by Z 2 , the space-time represents two orbifold planes which collide and re-emerge, a process proposed as an explanation of the hot big bang [J. Khoury, B. A. Ovrut, P. J. Steinhardt, and N. Turok, Phys. Rev. D 64, 123522 (2001).][P. J. Steinhardt and N. Turok, Science 296, 1436 (2002).][N. Turok, M. Perry, and P. J. Steinhardt, Phys. Rev. D 70, 106004 (2004).]. When the two planes are near, the light states of the theory consist of winding M2-branes, describing fundamental strings in a particular ten-dimensional background. They suffer no blue-shift as the M theory dimension collapses, and their equations of motion are regular across the transition from big crunch to big bang. In this paper, we study the classical evolution of fundamental strings across the singularity in some detail. We also develop a simple semiclassical approximation to the quantum evolution which allows one to compute the quantum production of excitations on the string and implement it in a simplified example
On membrane interactions and a three-dimensional analog of Riemann surfaces
International Nuclear Information System (INIS)
Kovacs, Stefano; Sato, Yuki; Shimada, Hidehiko
2016-01-01
Membranes in M-theory are expected to interact via splitting and joining processes. We study these effects in the pp-wave matrix model, in which they are associated with transitions between states in sectors built on vacua with different numbers of membranes. Transition amplitudes between such states receive contributions from BPS instanton configurations interpolating between the different vacua. Various properties of the moduli space of BPS instantons are known, but there are very few known examples of explicit solutions. We present a new approach to the construction of instanton solutions interpolating between states containing arbitrary numbers of membranes, based on a continuum approximation valid for matrices of large size. The proposed scheme uses functions on a two-dimensional space to approximate matrices and it relies on the same ideas behind the matrix regularisation of membrane degrees of freedom in M-theory. We show that the BPS instanton equations have a continuum counterpart which can be mapped to the three-dimensional Laplace equation through a sequence of changes of variables. A description of configurations corresponding to membrane splitting/joining processes can be given in terms of solutions to the Laplace equation in a three-dimensional analog of a Riemann surface, consisting of multiple copies of ℝ"3 connected via a generalisation of branch cuts. We discuss various general features of our proposal and we also present explicit analytic solutions.
Multiscale N=2 SUSY field theories, integrable systems and their stringy/brane origin
International Nuclear Information System (INIS)
Gorsky, A.; Gukov, S.; Mironov, A.
1998-01-01
We discuss supersymmetric Yang-Mills theories with multiple scales in the brane language. The issue concerns N=2 SUSY gauge theories with massive fundamental matter including the UV finite case of n f =2n c , theories involving products of SU(n) gauge groups with bifundamental matter, and systems with several parameters similar to Λ QCD . We argue that the proper integrable systems are, accordingly, twisted XXX SL(2) spin chain, SL(p) magnets and degenerations of the spin Calogero system. The issue of symmetries underlying integrable systems is addressed. Relations with the monopole systems are specially discussed. Brane pictures behind all these integrable structures in the IIB and M-theory are suggested. We argue that degrees of freedom in integrable systems are related to KK excitations in M-theory or D-particles in the IIA string theory, which substitute the infinite number of instantons in the field theory. This implies the presence of more BPS states in the low-energy sector. (orig.)
Grand Unification as a Bridge Between String Theory and Phenomenology
Pati, Jogesh C.
In the first part of this paper, we explain what empirical evidence points to the need for having an effective grand unification-like symmetry possessing the symmetry SU(4)-color in 4D. If one assumes the premises of a future predictive theory including gravity — be it string/M-theory or a reincarnation — this evidence then suggests that such a theory should lead to an effective grand unification-like symmetry as above in 4D, near the string-GUT-scale, rather than the standard model symmetry. Advantages of an effective supersymmetric G(224) = SU(2)L × SU(2)R × SU(4)c or SO(10) symmetry in 4D in explaining (i) observed neutrino oscillations, (ii) baryogenesis via leptogenesis, and (iii) certain fermion mass-relations are noted. And certain distinguishing tests of a SUSY G(224) or SO(10)-framework involving CP and flavor violations (as in μ → eγ, τ → μγ, edm's of the neutron and the electron) as well as proton decay are briefly mentioned. Recalling some of the successes we have had in our understanding of nature so far, and the current difficulties of string/M-theory as regards the large multiplicity of string vacua, some comments are made on the traditional goal of understanding vis a vis the recently evolved view of landscape and anthropism.
Grand Unification as a Bridge Between String Theory and Phenomenology
International Nuclear Information System (INIS)
Pati, J
2006-01-01
In the first part of the talk, I explain what empirical evidence points to the need for having an effective grand unification-like symmetry possessing the symmetry SU(4)-color in 4D. If one assumes the premises of a future predictive theory including gravity--be it string/M theory or a reincarnation--this evidence then suggests that such a theory should lead to an effective grand unification-like symmetry as above in 4D, near the string-GUT-scale, rather than the standard model symmetry. Advantages of an effective supersymmetric G(224) = SU(2) L x SU(2) R x SU(4) c or SO(10) symmetry in 4D in explaining (1) observed neutrino oscillations, (2) baryogenesis via leptogenesis, and (3) certain fermion mass-relations are noted. And certain distinguishing tests of a SUSY G(224) or SO(10)-framework involving CP and flavor violations (as in μ → eγ, τ → μγ, edm's of the neutron and the electron) as well as proton decay are briefly mentioned. Recalling some of the successes we have had in our understanding of nature so far, and the current difficulties of string/M theory as regards the large multiplicity of string vacua, some comments are made on the traditional goal of understanding vis a vis the recently evolved view of landscape and anthropism
Fermion Mass Textures in an M-Inspired Flipped SU(5) Model Derived from String
Ellis, Jonathan Richard; Lola, S; Nanopoulos, Dimitri V
1998-01-01
We are inspired by the facts that M-theory may reconcile the supersymmetric GUT scale with that of quantum gravity, and that it provides new avenues for low-energy supersymmetry breaking, to re-examine a flipped SU(5) model that has been derived from string and may possess an elevation to a fully-fledged M-phenomenological model. Using a complete analysis of all superpotential terms through the sixth order, we explore in this model a new flat potential direction that provides a pair of light Higgs doublets, yields realistic textures for the fermion mass matrices, and is free of R-violating interactions and dimension-five proton decay operators.
arXiv Gauge Backgrounds and Zero-Mode Counting in F-Theory
Bies, Martin; Weigand, Timo
2017-11-14
Computing the exact spectrum of charged massless matter is a crucial step towards understanding the effective field theory describing F-theory vacua in four dimensions. In this work we further develop a coherent framework to determine the charged massless matter in F-theory compactified on elliptic fourfolds, and demonstrate its application in a concrete example. The gauge background is represented, via duality with M-theory, by algebraic cycles modulo rational equivalence. Intersection theory within the Chow ring allows us to extract coherent sheaves on the base of the elliptic fibration whose cohomology groups encode the charged zero-mode spectrum. The dimensions of these cohomology groups are computed with the help of modern techniques from algebraic geometry, which we implement in the software gap. We exemplify this approach in models with an Abelian and non-Abelian gauge group and observe jumps in the exact massless spectrum as the complex structure moduli are varied. An extended mathematical appendix gi...
Booted domain wall and charged Kaigorodov space
International Nuclear Information System (INIS)
Cai Ronggen
2003-01-01
The Kaigorodov space is a homogeneous Einstein space and it describes a pp-wave propagating in anti-de Sitter space. It is conjectured in the literature that M-theory or string theory on the Kaigorodov space times a compact manifold is dual to a conformal field theory in an infinitely-boosted frame with constant momentum density. In this Letter we present a charged generalization of the Kaigorodov space by boosting a non-extremal charged domain wall to the ultrarelativity limit where the boost velocity approaches the speed of light. The finite boost of the domain wall solution gives the charged generalization of the Carter-Novotny-Horsky metric. We study the thermodynamics associated with the charged Carter-Novotny-Horsky space and discuss its relation to that of the static black domain walls and its implications in the domain wall/QFT (quantum field theory) correspondence
Symmetry and the Standard Model mathematics and particle physics
Robinson, Matthew
2011-01-01
While elementary particle physics is an extraordinarily fascinating field, the huge amount of knowledge necessary to perform cutting-edge research poses a formidable challenge for students. The leap from the material contained in the standard graduate course sequence to the frontiers of M-theory, for example, is tremendous. To make substantial contributions to the field, students must first confront a long reading list of texts on quantum field theory, general relativity, gauge theory, particle interactions, conformal field theory, and string theory. Moreover, waves of new mathematics are required at each stage, spanning a broad set of topics including algebra, geometry, topology, and analysis. Symmetry and the Standard Model: Mathematics and Particle Physics, by Matthew Robinson, is the first volume of a series intended to teach math in a way that is catered to physicists. Following a brief review of classical physics at the undergraduate level and a preview of particle physics from an experimentalist's per...
Monten, Ruben; Toldo, Chiara
2018-02-01
We present new AdS4 black hole solutions in N =2 gauged supergravity coupled to vector and hypermultiplets. We focus on a particular consistent truncation of M-theory on the homogeneous Sasaki–Einstein seven-manifold M 111, characterized by the presence of one Betti vector multiplet. We numerically construct static and spherically symmetric black holes with electric and magnetic charges, corresponding to M2 and M5 branes wrapping non-contractible cycles of the internal manifold. The novel feature characterizing these nonzero temperature configurations is the presence of a massive vector field halo. Moreover, we verify the first law of black hole mechanics and we study the thermodynamics in the canonical ensemble. We analyze the behavior of the massive vector field condensate across the small-large black hole phase transition and we interpret the process in the dual field theory.
State-space Manifold and Rotating Black Holes
Bellucci, Stefano
2010-01-01
We study a class of fluctuating higher dimensional black hole configurations obtained in string theory/ $M$-theory compactifications. We explore the intrinsic Riemannian geometric nature of Gaussian fluctuations arising from the Hessian of the coarse graining entropy, defined over an ensemble of brane microstates. It has been shown that the state-space geometry spanned by the set of invariant parameters is non-degenerate, regular and has a negative scalar curvature for the rotating Myers-Perry black holes, Kaluza-Klein black holes, supersymmetric $AdS_5$ black holes, $D_1$-$D_5$ configurations and the associated BMPV black holes. Interestingly, these solutions demonstrate that the principal components of the state-space metric tensor admit a positive definite form, while the off diagonal components do not. Furthermore, the ratio of diagonal components weakens relatively faster than the off diagonal components, and thus they swiftly come into an equilibrium statistical configuration. Novel aspects of the scali...
T-branes through 3d mirror symmetry
Energy Technology Data Exchange (ETDEWEB)
Collinucci, Andrés; Giacomelli, Simone [Physique Théorique et Mathématique and International Solvay Institutes,Université Libre de Bruxelles,C.P. 231, 1050 Bruxelles (Belgium); Savelli, Raffaele [Institut de Physique Théorique, CEA Saclay,Orme de Merisiers, F-91191 Gif-sur-Yvette (France); Valandro, Roberto [Dipartimento di Fisica, Università di Trieste,Strada Costiera 11, 34151 Trieste (Italy); INFN, Sezione di Trieste,Via Valerio 2, 34127 Trieste (Italy); Abdus Salam International Centre for Theoretical Physics,Strada Costiera 11, 34151 Trieste (Italy)
2016-07-19
T-branes are exotic bound states of D-branes, characterized by mutually non-commuting vacuum expectation values for the worldvolume scalars. The M/F-theory geometry lifting D6/D7-brane configurations is blind to the T-brane data. In this paper, we make this data manifest, by probing the geometry with an M2-brane. We find that the effect of a T-brane is to deform the membrane worldvolume superpotential with monopole operators, which partially break the three-dimensional flavor symmetry, and reduce supersymmetry from N=4 to N=2. Our main tool is 3d mirror symmetry. Through this language, a very concrete framework is developed for understanding T-branes in M-theory. This leads us to uncover a new class of N=2 quiver gauge theories, whose Higgs branches mimic those of membranes at ADE singularities, but whose Coulomb branches differ from their N=4 counterparts.
Black Holes and Large Order Quantum Geometry
Huang, Min-xin; Mariño, Marcos; Tavanfar, Alireza
2009-01-01
We study five-dimensional black holes obtained by compactifying M theory on Calabi-Yau threefolds. Recent progress in solving topological string theory on compact, one-parameter models allows us to test numerically various conjectures about these black holes. We give convincing evidence that a microscopic description based on Gopakumar-Vafa invariants accounts correctly for their macroscopic entropy, and we check that highly nontrivial cancellations -which seem necessary to resolve the so-called entropy enigma in the OSV conjecture- do in fact occur. We also study analytically small 5d black holes obtained by wrapping M2 branes in the fiber of K3 fibrations. By using heterotic/type II duality we obtain exact formulae for the microscopic degeneracies in various geometries, and we compute their asymptotic expansion for large charges.
2015-01-01
Welcome to String-Math 2015 at Sanya. The conference will be opened in December 31, 2015- January 4, 2016. String theory plays a central role in theoretical physics as a candidate for the quantum theory unifying gravity with other interactions. It has profound connections with broad branches of modern mathematics ever since the birth. In the last decades, the prosperous interaction, built upon the joint efforts from both mathematicians and physicists, has given rise to marvelous deep results in supersymmetric gauge theory, topological string, M-theory and duality on the physics side as well as in algebraic geometry, differential geometry, algebraic topology, representation theory and number theory on the mathematics side. The interplay is two-fold. The mathematics has provided powerful tools to fulfill the physical interconnection of ideas and clarify physical structures to understand the nature of string theory. On the other hand, ideas from string theory and quantum field theory have been a source of sign...
M-strings, Elliptic Genera and N=4 String Amplitudes
Hohenegger, Stefan
2014-01-01
We study mass-deformed N=2 gauge theories from various points of view. Their partition functions can be computed via three dual approaches: firstly, (p,q)-brane webs in type II string theory using Nekrasov's instanton calculus, secondly, the (refined) topological string using the topological vertex formalism and thirdly, M theory via the elliptic genus of certain M-strings configurations. We argue for a large class of theories that these approaches yield the same gauge theory partition function which we study in detail. To make their modular properties more tangible, we consider a fourth approach by connecting the partition function to the equivariant elliptic genus of R^4 through a (singular) theta-transform. This form appears naturally as a specific class of one-loop scattering amplitudes in type II string theory on T^2, which we calculate explicitly.
International Nuclear Information System (INIS)
Elizalde, E.; Makarenko, A.N.; Obukhov, V.V.; Osetrin, K.E.; Filippov, A.E.
2007-01-01
Six-dimensional Einstein-Gauss-Bonnet gravity (with a linear Gauss-Bonnet term) is investigated. This theory is inspired by basic features of results coming from string and M-theory. Dynamical compactification is carried out and it is seen that a four-dimensional accelerating FRW universe is recovered, when the two-dimensional internal space radius shrinks. A non-perturbative structure of the corresponding theory is identified which has either three or one stable fixed points, depending on the Gauss-Bonnet coupling being positive or negative. A much richer structure than in the case of the perturbative regime of the dynamical compactification recently studied by Andrew, Bolen, and Middleton is exhibited
Gravity how the weakest force in the universe shaped our lives
Clegg, Brian
2012-01-01
Gravity is one of the most accepted laws of science. Drop an object and it falls to earth because of the attraction between the earth and the object. What alerts the earth and the object to act? Is there a sort of communication between them? Theoretical physicists have struggled to explain gravitational attraction over distance since Einstein posed his theories of special and general relativity. Quantum theory, string theory, M theory, and other theoretical inquiries have failed to solve the riddle. In his history of gravity from the Big Bang to the present, popular science author Clegg recounts international efforts to understand what is thought to be the weakest yet most essential force holding the universe together. Black holes, warps in space and time, and antimatter are featured in this wide-ranging account, which will be of interest to science students and readers of science fiction.
Type II pp-wave matrix models from point-like gravitons
International Nuclear Information System (INIS)
Lozano, Yolanda; RodrIguez-Gomez, Diego
2006-01-01
The BMN Matrix model can be regarded as a theory of coincident M-theory gravitons, which expand by Myers dielectric effect into the 2-sphere and 5-sphere giant graviton vacua of the theory. In this note we show that, in the same fashion, Matrix String theory in Type IIA pp-wave backgrounds arises from the action for coincident Type IIA gravitons. In Type IIB, we show that the action for coincident gravitons in the maximally supersymmetric pp-wave background gives rise to a Matrix model which supports fuzzy 3-sphere giant graviton vacua with the right behavior in the classical limit. We discuss the relation between our Matrix model and the Tiny Graviton Matrix theory
The problem of time quantum mechanics versus general relativity
Anderson, Edward
2017-01-01
This book is a treatise on time and on background independence in physics. It first considers how time is conceived of in each accepted paradigm of physics: Newtonian, special relativity, quantum mechanics (QM) and general relativity (GR). Substantial differences are moreover uncovered between what is meant by time in QM and in GR. These differences jointly source the Problem of Time: Nine interlinked facets which arise upon attempting concurrent treatment of the QM and GR paradigms, as is required in particular for a background independent theory of quantum gravity. A sizeable proportion of current quantum gravity programs - e.g. geometrodynamical and loop quantum gravity approaches to quantum GR, quantum cosmology, supergravity and M-theory - are background independent in this sense. This book's foundational topic is thus furthermore of practical relevance in the ongoing development of quantum gravity programs. This book shows moreover that eight of the nine facets of the Problem of Time already occur upon ...
On R4 threshold corrections in type IIB string theory and (p,q)-string instantons
International Nuclear Information System (INIS)
Kiritsis, E.; Pioline, B.
1997-01-01
We obtain the exact non-perturbative thresholds of R 4 terms in type IIB string theory compactified to eight and seven dimensions. These thresholds are given by the perturbative tree-level and one-loop results together with the contribution of the D-instantons and of the (p,q)-string instantons. The invariance under U-duality is made manifest by rewriting the sum as a non-holomorphic-invariant modular function of the corresponding discrete U-duality group. In the eight-dimensional case, the threshold is the sum of an order-1 Eisenstein series for SL(2,Z) and an order-3/2 Eisenstein series for SL(3,Z). The seven-dimensional result is given by the order-3/2 Eisenstein series for SL(5,Z). We also conjecture formulae for the non-perturbative thresholds in lower-dimensional compactifications and discuss the relation with M-theory. (orig.)
Standard model fermions and N=8 supergravity
Energy Technology Data Exchange (ETDEWEB)
Nicolai, Hermann [Max Planck Institute for Gravitational Physics (Albert Einstein Institute), Am Muehlenberg 1, Potsdam-Golm (Germany)
2016-07-01
In a scheme originally proposed by Gell-Mann, and subsequently shown to be realized at the SU(3) x U(1) stationary point of maximal gauged SO(8) supergravity, the 48 spin-1/2 fermions of the theory remaining after the removal of eight Goldstinos can be identified with the 48 quarks and leptons (including right-chiral neutrinos) of the Standard model, provided one identifies the residual SU(3) with the diagonal subgroup of the color group SU(3){sub c} and a family symmetry SU(3){sub f}. However, there remained a systematic mismatch in the electric charges by a spurion charge of ± 1/6. We here identify the ''missing'' U(1) that rectifies this mismatch, and that takes a surprisingly simple, though unexpected form, and show how it is related to the conjectured R symmetry K(E10) of M Theory.
Spinning and rotating strings for N=1 SYM theory and brane constructions
International Nuclear Information System (INIS)
Schvellinger, Martin
2004-01-01
We obtain spinning and rotating closed string solutions in AdS 5 x T 1,1 background, and show how these solutions can be mapped onto rotating closed strings embedded in configurations of intersecting branes in type IIA string theory. Then, we discuss spinning closed string solutions in the UV limit of the Klebanov-Tseytlin background, and also properties of classical solutions in the related intersecting brane constructions in the UV limit. We comment on extensions of this analysis to the deformed conifold background, and in the corresponding intersecting brane construction, as well as its relation to the deep IR limit of the Klebanov-Strassler solution. We briefly discuss on the relation between type IIA brane constructions and their related M-theory descriptions, and how solitonic solutions are related in both descriptions. (author)
Conformally coupled scalars, instantons and vacuum instability in AdS{sub 4}
Energy Technology Data Exchange (ETDEWEB)
De Haro, S. [King' s College London (United Kingdom). Dept. of Mathematics; Papadimitriou, I. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Petkou, A.C. [Crete Univ., Keraklion (Greece). Dept. of Physics
2006-11-15
We show that a scalar field conformally coupled to AdS gravity in four dimensions with a quartic self-interaction can be embedded into M-theory. The holographic effective action and effective potential are exactly calculated, allowing us to study non-perturbatively the stability of AdS{sub 4} in the presence of the conformally coupled scalar. It is shown that there exists a one-parameter family of conformal scalar boundary conditions for which the boundary theory has an unstable vacuum. In this case, the bulk theory has instanton solutions that mediate the decay of the AdS{sub 4} space. These results match nicely with the vacuum structure and the existence of instantons in an effective three-dimensional boundary model.
The incredible shrinking torus
International Nuclear Information System (INIS)
Fischler, W.; Susskind, L.
1997-01-01
Using M(atrix) theory, the dualities of toroidally compactified M-theory can be formulated as properties of super Yang Mills theories in various dimensions. We consider the cases of compactification on 1-, 2-, 3-, 4- and 5-dimensional tori. The dualities required by string theory lead to conjectures of remarkable symmetries and relations between field theories as well as extremely unusual dynamical properties. By studying the theories in the limit of vanishingly small tori, a wealth of information is obtained about strongly coupled fixed points of super Yang-Mills theory in various dimensions. Perhaps the most striking behavior, as noted by Rozali in this context, is the emergence of an additional dimension of space in the case of a 4-torus. (orig.)
Deformed N = 8 supergravity from IIA strings and its Chern-Simons duals
Energy Technology Data Exchange (ETDEWEB)
Guarino, Adolfo [Nikhef Theory Group, Amsterdam (Netherlands); Jafferis, Daniel L. [Center for the Fundamental Laws of Nature, Harvard University, Cambridge, MA (United States); Varela, Oscar [Center for the Fundamental Laws of Nature, Harvard University, Cambridge, MA (United States); Centre de Physique Theorique, Ecole Polytechnique, CNRS UMR 7644, Palaiseau (France)
2016-04-15
Do electric/magnetic deformations of N = 8 supergravity enjoy a string/M-theory origin, or are they just a fourdimensional artefact? We address this question for the gauging of a group closely related to SO(8): its contraction ISO(7). We argue that the deformed ISO(7) supergravity arises from consistent truncation of massive IIA supergravity on S{sup 6}, and its electric/magnetic deformation parameter descends directly from the Romans mass. The critical points of the supergravity uplift to AdS{sub 4} massive type IIA vacua and the corresponding CFT{sub 3} duals are identified as super-Chern-Simons-matter theories with gauge group SU(N) and level k given also by the Romans mass. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Directory of Open Access Journals (Sweden)
Alexander Burinskii
2013-01-01
Full Text Available The 4D Kerr geometry displays many wonderful relations with quantum world and, in particular, with superstring theory. The lightlike structure of fields near the Kerr singular ring is similar to the structure of Sen solution for a closed heterotic string. Another string, open and complex, appears in the complex representation of the Kerr geometry initiated by Newman. Combination of these strings forms a membrane source of the Kerr geometry which is parallel to the structure of M-theory. In this paper we give one more evidence of this relationship, emergence of the Calabi-Yau twofold (K3 surface in twistorial structure of the Kerr geometry as a consequence of the Kerr theorem. Finally, we indicate that the Kerr stringy system may correspond to a complex embedding of the critical N = 2 superstring.
Instantons, hypermultiplets and the heterotic string
International Nuclear Information System (INIS)
Halmagyi, Nick; Melnikov, Ilarion V.; Sethi, Savdeep
2007-01-01
Hypermultiplet couplings in type IIA string theory on a Calabi-Yau space can be quantum corrected by D2-brane instantons wrapping special Lagrangian cycles. On the other hand, hypermultiplet couplings in the heterotic string on a K3 surface are corrected by world-sheet instantons wrapping curves. In a class of examples, we relate these two sets of instanton corrections. We first present an analogue of the c-map for the heterotic string via a dual flux compactification of M-theory. Using this duality, we propose two ways of capturing quantum corrections to hypermultiplets. We then use the orientifold limit of certain F-theory compactifications to relate curves in K3 to special Lagrangians in dual type IIA compactifications. We conclude with some results from perturbative string theory for hypermultiplet F-terms and a conjecture about the topology of brane instantons
BPS dynamics of the triple (p,q) string junction
International Nuclear Information System (INIS)
Rey, S.-J.; Yee, J.-T.
1998-01-01
We study the dynamics of the triple junction of (p,q) strings in type IIB string theory. We probe the tension and mass density of (p,q) strings by studying harmonic fluctuations of the triple junction. We show that they agree perfectly with the BPS formula provided a suitable geometric interpretation of the junction is given. We provide a precise statement of the BPS limit and force-balance property. At weak coupling and sufficiently dense limit, we argue that a (p,q) string embedded in the string network is a 'wiggly string', whose low-energy dynamics can be described via a renormalization group evolved, smooth effective non-relativistic string. We also suggest the possibility that, upon type IIB strings being promoted to the M-theory membrane, there can exist 'evanescent' bound-states at the triple junction in the continuum. (orig.)
Warped Kähler potentials and fluxes
Energy Technology Data Exchange (ETDEWEB)
Martucci, Luca [Dipartimento di Fisica ed Astronomia “Galileo Galilei' ,Università di Padova & I.N.F.N. Sezione di Padova,Via Marzolo 8, 35131 Padova (Italy)
2017-01-13
The four-dimensional effective theory for type IIB warped flux compactifications proposed in https://www.doi.org/10.1007/JHEP03(2015)067 is completed by taking into account the backreaction of the Kähler moduli on the three-form fluxes. The only required modification consists in a flux-dependent contribution to the chiral fields parametrising the Kähler moduli. The resulting supersymmetric effective theory satisfies the no-scale condition and consistently combines previous partial results present in the literature. Similar results hold for M-theory warped compactifications on Calabi-Yau fourfolds, whose effective field theory and Kähler potential are also discussed.
Abelian tensor hierarchy in 4D, N=1 superspace
International Nuclear Information System (INIS)
Becker, Katrin; Becker, Melanie; III, William D. Linch; Robbins, Daniel
2016-01-01
With the goal of constructing the supersymmetric action for all fields, massless and massive, obtained by Kaluza-Klein compactification from type II theory or M-theory in a closed form, we embed the (Abelian) tensor hierarchy of p-forms in four-dimensional, N=1 superspace and construct its Chern-Simons-like invariants. When specialized to the case in which the tensors arise from a higher-dimensional theory, the invariants may be interpreted as higher-dimensional Chern-Simons forms reduced to four dimensions. As an application of the formalism, we construct the eleven-dimensional Chern-Simons form in terms of four-dimensional, N=1 superfields.
Abelian tensor hierarchy in 4D, N=1 superspace
Energy Technology Data Exchange (ETDEWEB)
Becker, Katrin; Becker, Melanie; III, William D. Linch; Robbins, Daniel [George P. and Cynthia W. Mitchell Institute for Fundamental Physics and Astronomy,Texas A& M University, College Station, TX 77843 (United States)
2016-03-09
With the goal of constructing the supersymmetric action for all fields, massless and massive, obtained by Kaluza-Klein compactification from type II theory or M-theory in a closed form, we embed the (Abelian) tensor hierarchy of p-forms in four-dimensional, N=1 superspace and construct its Chern-Simons-like invariants. When specialized to the case in which the tensors arise from a higher-dimensional theory, the invariants may be interpreted as higher-dimensional Chern-Simons forms reduced to four dimensions. As an application of the formalism, we construct the eleven-dimensional Chern-Simons form in terms of four-dimensional, N=1 superfields.
Heisenberg groups and noncommutative fluxes
International Nuclear Information System (INIS)
Freed, Daniel S.; Moore, Gregory W.; Segal, Graeme
2007-01-01
We develop a group-theoretical approach to the formulation of generalized abelian gauge theories, such as those appearing in string theory and M-theory. We explore several applications of this approach. First, we show that there is an uncertainty relation which obstructs simultaneous measurement of electric and magnetic flux when torsion fluxes are included. Next, we show how to define the Hilbert space of a self-dual field. The Hilbert space is Z 2 -graded and we show that, in general, self-dual theories (including the RR fields of string theory) have fermionic sectors. We indicate how rational conformal field theories associated to the two-dimensional Gaussian model generalize to (4k+2)-dimensional conformal field theories. When our ideas are applied to the RR fields of string theory we learn that it is impossible to measure the K-theory class of a RR field. Only the reduction modulo torsion can be measured
Wilson loops on three-manifolds and their M2-brane duals
International Nuclear Information System (INIS)
Farquet, Daniel; Sparks, James
2014-01-01
We compute the large N limit of Wilson loop expectation values for a broad class of N=2 supersymmetric gauge theories defined on a general class of background three-manifolds M_3, diffeomorphic to S"3. We find a simple closed formula which depends on the background geometry only through a certain supersymmetric Killing vector field. The supergravity dual of such a Wilson loop is an M2-brane wrapping the M-theory circle, together with a complex curve Σ_2 in a self-dual Einstein manifold M_4, whose conformal boundary is M_3. We show that the regularized action of this M2-brane also depends only on the supersymmetric Killing vector, precisely reproducing the large N field theory computation.
"Beyond the Big Bang: a new view of cosmology"
CERN. Geneva
2012-01-01
and parameters? Can one conceive of a completion of the scenario which resolves the big bang singularity and explains the dark energy now coming to dominate? Are we forced to resort to anthropic explanations? In this talk, I will develop an alternate picture, in which the big bang singularity is resolved and in which the value of the dark energy might be fixed by physical processes. The key is a resolution of the singularity. Using a combination of arguments,involving M theory and holography as well as analytic continuation in time within the low energy effective theory, I argue that there is a unique way to match cosmic evolution across the big bang singularity. The latter is no longer the beginning of time but is instead the gateway to an eternal, cyclical universe. If time permits, I shall describe new work c...
A universal counting of black hole microstates in AdS4
Azzurli, Francesco; Bobev, Nikolay; Crichigno, P. Marcos; Min, Vincent S.; Zaffaroni, Alberto
2018-02-01
Many three-dimensional N=2 SCFTs admit a universal partial topological twist when placed on hyperbolic Riemann surfaces. We exploit this fact to derive a universal formula which relates the planar limit of the topologically twisted index of these SCFTs and their three-sphere partition function. We then utilize this to account for the entropy of a large class of supersymmetric asymptotically AdS4 magnetically charged black holes in M-theory and massive type IIA string theory. In this context we also discuss novel AdS2 solutions of eleven-dimensional supergravity which describe the near horizon region of large new families of supersymmetric black holes arising from M2-branes wrapping Riemann surfaces.
Accelerating cosmologies from exponential potentials
International Nuclear Information System (INIS)
Neupane, Ishwaree P.
2003-11-01
It is learnt that exponential potentials of the form V ∼ exp(-2cφ/M p ) arising from the hyperbolic or flux compactification of higher-dimensional theories are of interest for getting short periods of accelerated cosmological expansions. Using a similar potential but derived for the combined case of hyperbolic-flux compactification, we study a four-dimensional flat (or open) FRW cosmologies and give analytic (and numerical) solutions with exponential behavior of scale factors. We show that, for the M-theory motivated potentials, the cosmic acceleration of the universe can be eternal if the spatial curvature of the 4d spacetime is negative, while the acceleration is only transient for a spatially flat universe. We also briefly discuss about the mass of massive Kaluza-Klein modes and the dynamical stabilization of the compact hyperbolic extra dimensions. (author)
Quintessence as a run-away dilaton
Gasperini, M; Veneziano, Gabriele
2002-01-01
We consider a late-time cosmological model based on a recent proposal that the infinite-bare-coupling limit of superstring/M-theory exists and has good phenomenological properties, including a vanishing cosmological constant, and a massless, decoupled dilaton. As it runs away to $+ \\infty$, the dilaton can play the role of the quintessence field recently advocated to drive the late-time accelerated expansion of the Universe. If, as suggested by some string theory examples, appreciable deviations from General Relativity persist even today in the dark matter sector, the Universe may smoothly evolve from an initial "focussing" stage, lasting till radiation-matter equality, to a "dragging" regime, which eventually gives rise to an accelerated expansion with frozen $\\Omega(\\rm{dark energy})/\\Omega(\\rm{dark matter})$.
Exceptional versus superPoincaré algebra as the defining symmetry of maximal supergravity
International Nuclear Information System (INIS)
Ananth, Sudarshan; Brink, Lars; Majumdar, Sucheta
2016-01-01
We describe how one may use either the superPoincaré algebra or the exceptional algebra to construct maximal supergravity theories in the light-cone formalism. The d=4 construction shows both symmetries albeit in a non-linearly realized manner. In d=11, we find that we have to choose which of these two symmetries to use, in constructing the theory. In order to understand the other “unused" symmetry, one has to perform a highly non-trivial field redefinition. We argue that this shows that one cannot trust counterterm arguments that do not take the full symmetry of the theory into account. Finally we discuss possible consequences for Superstring theory and M-theory.
Chiral 2d theories from N=4 SYM with varying coupling
Energy Technology Data Exchange (ETDEWEB)
Lawrie, Craig [Institut für Theoretische Physik, Ruprecht-Karls-Universität,Philosophenweg 19, 69120 Heidelberg (Germany); Schäfer-Nameki, Sakura [Mathematical Institute, University of Oxford,Woodstock Road, Oxford, OX2 6GG (United Kingdom); Weigand, Timo [Institut für Theoretische Physik, Ruprecht-Karls-Universität,Philosophenweg 19, 69120 Heidelberg (Germany)
2017-04-19
We study 2d chiral theories arising from 4d N=4 Super-Yang Mills (SYM) with varying coupling τ. The 2d theory is obtained by dimensional reduction of N=4 SYM on a complex curve with a partial topological twist that accounts for the non-constant τ. The resulting 2d theories can preserve (0,n) with n=2,4,6,8 chiral supersymmetry, and have a natural realization in terms of strings from wrapped D3-branes in F-theory. We determine the twisted dimensional reduction, as well as the spectrum and anomaly polynomials of the resulting strings in various dimensions. We complement this by considering the dual M-theory configurations, which can either be realized in terms of M5-branes wrapped on complex surfaces, or M2-branes on curves that result in 1d supersymmetric quantum mechanics.
Supersymmetric backgrounds, the Killing superalgebra, and generalised special holonomy
Energy Technology Data Exchange (ETDEWEB)
Coimbra, André [Institut des Hautes Études Scientifiques, Le Bois-Marie,35 route de Chartres, F-91440 Bures-sur-Yvette (France); Strickland-Constable, Charles [Institut des Hautes Études Scientifiques, Le Bois-Marie,35 route de Chartres, F-91440 Bures-sur-Yvette (France); Institut de physique théorique, Université Paris Saclay, CEA, CNRS,Orme des Merisiers, F-91191 Gif-sur-Yvette (France)
2016-11-10
We prove that, for M theory or type II, generic Minkowski flux backgrounds preserving N supersymmetries in dimensions D≥4 correspond precisely to integrable generalised G{sub N} structures, where G{sub N} is the generalised structure group defined by the Killing spinors. In other words, they are the analogues of special holonomy manifolds in E{sub d(d)}×ℝ{sup +} generalised geometry. In establishing this result, we introduce the Kosmann-Dorfman bracket, a generalisation of Kosmann’s Lie derivative of spinors. This allows us to write down the internal sector of the Killing superalgebra, which takes a rather simple form and whose closure is the key step in proving the main result. In addition, we find that the eleven-dimensional Killing superalgebra of these backgrounds is necessarily the supertranslational part of the N-extended super-Poincaré algebra.
Matrix model as a mirror of Chern-Simons theory
International Nuclear Information System (INIS)
Aganagic, Mina; Klemm, Albrecht; Marino, Marcos; Vafa, Cumrun
2004-01-01
Using mirror symmetry, we show that Chern-Simons theory on certain manifolds such as lens spaces reduces to a novel class of Hermitian matrix models, where the measure is that of unitary matrix models. We show that this agrees with the more conventional canonical quantization of Chern-Simons theory. Moreover, large N dualities in this context lead to computation of all genus A-model topological amplitudes on toric Calabi-Yau manifolds in terms of matrix integrals. In the context of type IIA superstring compactifications on these Calabi-Yau manifolds with wrapped D6 branes (which are dual to M-theory on G2 manifolds) this leads to engineering and solving F-terms for N=1 supersymmetric gauge theories with superpotentials involving certain multi-trace operators. (author)
Inflationary cosmologies from compactification?
International Nuclear Information System (INIS)
Wohlfarth, Mattias N.R.
2004-01-01
We consider the compactification of (d+n)-dimensional pure gravity and of superstring or M-theory on an n-dimensional internal space to a d-dimensional Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmology, with a spatial curvature k=0,±1, in the Einstein conformal frame. The internal space is taken to be a product of Einstein spaces, each of which is allowed to have arbitrary curvature and a time-dependent volume. By investigating the effective d-dimensional scalar potential, which is a sum of exponentials, it is shown that such compactifications, in the k=0,+1 cases, do not lead to large amounts of accelerating expansion of the scale factor of the resulting FLRW universe, and, in particular, do not lead to inflation. The case k=-1 admits solutions with eternal accelerating expansion for which the acceleration, however, tends to zero at late times
Signals for Non-Cummutative Interactions at Linear Colliders
International Nuclear Information System (INIS)
Rizzo, Thomas G.
2001-01-01
Recent theoretical results have demonstrated that non-commutative geometries naturally appear within the context of string/M-theory. One consequence of this possibility is that QED takes on a non-abelian nature due to the introduction of 3- and 4-point functions. In addition, each QED vertex acquires a momentum dependent phase factor. We parameterize the effects of non-commutative space-time co-ordinates and show that they lead to observable signatures in several 2 → 2 QED processes in e + e - collisions. In particular, we examine pair annihilation, Moller and Bhabha scattering, as well as γγ → γγ scattering and show that non-commutative scales of order a TeV can be probed at high energy linear colliders
Boucher, Jill
2012-05-01
In this review, the history of the theory of mind (ToM) theory of autistic spectrum disorder (ASD) is outlined (in which ToM is indexed by success on false belief tasks), and the explanatory power and psychological causes of impaired ToM in ASD are critically discussed. It is concluded that impaired ToM by itself has only limited explanatory power, but that explorations of the psychological precursors of impaired ToM have been fruitful in increasing understanding of mindreading impairments in ASD (where 'mindreading' refers those abilities that underlie triadic interaction as well as ToM). It is argued that early explanations of impaired mindreading are untenable for various reasons, but that impairments of dyadic interaction in ASD that could lead to impaired ability to represent others' mental states may be the critical psychological cause, or causes, of impaired ToM. The complexity of causal routes to impaired ToM is emphasized.
Construction of Einstein-Sasaki metrics in D≥7
International Nuclear Information System (INIS)
Lue, H.; Pope, C. N.; Vazquez-Poritz, J. F.
2007-01-01
We construct explicit Einstein-Kaehler metrics in all even dimensions D=2n+4≥6, in terms of a 2n-dimensional Einstein-Kaehler base metric. These are cohomogeneity 2 metrics which have the new feature of including a NUT-type parameter, or gravomagnetic charge, in addition to..' in addition to mass and rotation parameters. Using a canonical construction, these metrics all yield Einstein-Sasaki metrics in dimensions D=2n+5≥7. As is commonly the case in this type of construction, for suitable choices of the free parameters the Einstein-Sasaki metrics can extend smoothly onto complete and nonsingular manifolds, even though the underlying Einstein-Kaehler metric has conical singularities. We discuss some explicit examples in the case of seven-dimensional Einstein-Sasaki spaces. These new spaces can provide supersymmetric backgrounds in M theory, which play a role in the AdS 4 /CFT 3 correspondence
On the fairlie's Moyal formulation of M(atrix)-theory
International Nuclear Information System (INIS)
Hssaini, M.; Sedra, M.B.; Bennai, M.; Maroufi, B.
2000-07-01
Starting from the Moyal formulation of M-theory in the large N-limit, we propose to reexamine the associated membrane equations of motion in 10 dimensions formulated in terms of Poisson bracket. Among the results obtained, we rewrite the coupled first order Nahm's equations into a simple form leading in turn to their systematic relation with SU(∞) Yang Mills equations of motion. The former are interpreted as the vanishing condition of some conserved currents which we propose. We also develop an algebraic analysis in which an ansatz is considered and find an explicit form for the membrane solution of our problem. Typical solutions known in literature can also emerge as special cases of the proposed solution. (author)
Spectral properties in supersymmetric matrix models
International Nuclear Information System (INIS)
Boulton, Lyonell; Garcia del Moral, Maria Pilar; Restuccia, Alvaro
2012-01-01
We formulate a general sufficiency criterion for discreteness of the spectrum of both supersymmmetric and non-supersymmetric theories with a fermionic contribution. This criterion allows an analysis of Hamiltonians in complete form rather than just their semiclassical limits. In such a framework we examine spectral properties of various (1+0) matrix models. We consider the BMN model of M-theory compactified on a maximally supersymmetric pp-wave background, different regularizations of the supermembrane with central charges and a non-supersymmetric model comprising a bound state of N D2 with m D0. While the first two examples have a purely discrete spectrum, the latter has a continuous spectrum with a lower end given in terms of the monopole charge.
Amoroso, Richard L.
HÉCTOR A.A brief introductory survey of Unified Field Mechanics (UFM) is given from the perspective of a Holographic Anthropic Multiverse cosmology in 12 `continuous-state' dimensions. The paradigm with many new parameters is cast in a scale-invariant conformal covariant Dirac polarized vacuum utilizing extended HD forms of the de Broglie-Bohm and Cramer interpretations of quantum theory. The model utilizes a unique form of M-Theory based in part on the original hadronic form of string theory that had a variable string tension, TS and included a tachyon. The model is experimentally testable, thus putatively able to demonstrate the existence of large-scale additional dimensionality (LSXD), test for QED violating tight-bound state spectral lines in hydrogen `below' the lowest Bohr orbit, and surmount the quantum uncertainty principle utilizing a hyperincursive Sagnac Effect resonance hierarchy.
G2 holonomy, mirror symmetry and phases of N = 1 SYM
International Nuclear Information System (INIS)
Hosomichi, Kazuo; Page, David C.
2005-01-01
We study the phase structure of four-dimensional N = 1 super Yang-Mills theories realized on D6-branes wrapping the RP 3 of a Z 2 orbifold of the deformed conifold. The non-trivial fundamental group of RP 3 allows for the gauge group to be broken to various product groups by Z 2 Wilson lines. We study the classical moduli space of theories in various pictures related by dualities including an M-theory lift. The quantum moduli space is analyzed in a dual IIB theory, where a complex curve contained in the target space plays a key role. We find that the quantum moduli space is made up of several branches, characterized by the presence or absence of a low energy U(1) gauge symmetry, which are connected at points of monopole condensation. The resulting picture of the quantum moduli space shows how the various gauge theories with different product gauge groups are connected to one another
The cyclic universe: An informal introduction
International Nuclear Information System (INIS)
Steinhaxdt, Paul J.; Turok, Neil
2003-01-01
The Cyclic Model is a radical, new cosmological scenario which proposes that the Universe undergoes an endless sequence of epochs which begin with a 'big bang' and end in a 'big crunch.' When the Universes bounces from contraction to re-expansion, the temperature and density remain finite. The model does not include a period of rapid inflation, yet it reproduces all of the successful predictions of standard big bang and inflationary cosmology. We point out numerous novel elements that have not been used previously which may open the door to further alternative cosmologies. Although the model is motivated by M-theory, branes and extra dimensions, here we show that the scenario can be described almost entirely in terms of conventional 4d field theory and 4d cosmology
Topological resolution of gauge theory singularities
Saracco, Fabio; Tomasiello, Alessandro; Torroba, Gonzalo
2013-08-01
Some gauge theories with Coulomb branches exhibit singularities in perturbation theory, which are usually resolved by nonperturbative physics. In string theory this corresponds to the resolution of timelike singularities near the core of orientifold planes by effects from F or M theory. We propose a new mechanism for resolving Coulomb branch singularities in three-dimensional gauge theories, based on Chern-Simons interactions. This is illustrated in a supersymmetric SU(2) Yang-Mills-Chern-Simons theory. We calculate the one-loop corrections to the Coulomb branch of this theory and find a result that interpolates smoothly between the high-energy metric (that would exhibit the singularity) and a regular singularity-free low-energy result. We suggest possible applications to singularity resolution in string theory and speculate a relationship to a similar phenomenon for the orientifold six-plane in massive IIA supergravity.
Five-dimensional gauge theory and compactification on a torus
Haghighat, Babak; Vandoren, Stefan
2011-09-01
We study five-dimensional minimally supersymmetric gauge theory compactified on a torus down to three dimensions, and its embedding into string/M-theory using geometric engineering. The moduli space on the Coulomb branch is hyperkähler equipped with a metric with modular transformation properties. We determine the one-loop corrections to the metric and show that they can be interpreted as worldsheet and D1-brane instantons in type IIB string theory. Furthermore, we analyze instanton corrections coming from the solitonic BPS magnetic string wrapped over the torus. In particular, we show how to compute the path-integral for the zero-modes from the partition function of the M5 brane, or, using a 2d/4d correspondence, from the partition function of N=4 SYM theory on a Hirzebruch surface.
Introduction to string theory and string compactifications
International Nuclear Information System (INIS)
GarcIa-Compean, Hugo
2005-01-01
Basics of some topics on perturbative and non-perturbative string theory are reviewed. After a mathematical survey of the Standard Model of particle physics and GUTs, the bosonic string kinematics for the free case and with interaction is described. The effective action of the bosonic string and the spectrum is also discussed. T-duality in closed and open strings and the definition of D-brane are surveyed. Five perturbative superstring theories and their spectra is briefly outlined. Calabi-Yau three-fold compactifications of heterotic strings and their relation to some four-dimensional physics are given. Finally, non-perturbative issues like S-duality, M-theory and F-theory are also reviewed
New Supersymmetric String Compactifications
Energy Technology Data Exchange (ETDEWEB)
Kachru, Shamit
2002-11-25
We describe a new class of supersymmetric string compactifications to 4d Minkowski space. These solutions involve type II strings propagating on (orientifolds of) non Calabi-Yau spaces in the presence of background NS and RR fluxes. The simplest examples have descriptions as cosets, generalizing the three-dimensional nilmanifold. They can also be thought of as twisted tori. We derive a formula for the (super)potential governing the light fields, which is generated by the fluxes and certain ''twists'' in the geometry. Detailed consideration of an example also gives strong evidence that in some cases, these exotic geometries are related by smooth transitions to standard Calabi-Yau or G2 compactifications of M-theory.
Framing and localization in Chern-Simons theories with matter
Energy Technology Data Exchange (ETDEWEB)
Bianchi, Marco S. [Center for Research in String Theory - School of Physics and Astronomy,Queen Mary University of London,Mile End Road, London E1 4NS (United Kingdom); Griguolo, Luca [Dipartimento di Fisica e Scienze della Terra, Università di Parma andINFN Gruppo Collegato di Parma,Viale G.P. Usberti 7/A, 43100 Parma (Italy); Leoni, Matias [Physics Department, FCEyN-UBA & IFIBA-CONICET,Ciudad Universitaria, Pabellón I, 1428, Buenos Aires (Argentina); Mauri, Andrea [Dipartimento di Fisica, Università degli studi di Milano-Bicocca,Piazza della Scienza 3, I-20126 Milano (Italy); Penati, Silvia [Dipartimento di Fisica, Università degli studi di Milano-Bicocca,Piazza della Scienza 3, I-20126 Milano (Italy); INFN, Sezione di Milano-Bicocca,Piazza della Scienza 3, I-20126 Milano (Italy); Seminara, Domenico [Dipartimento di Fisica, Università di Firenze and INFN Sezione di Firenze,via G. Sansone 1, 50019 Sesto Fiorentino (Italy)
2016-06-22
Supersymmetric localization provides exact results that should match QFT computations in some regularization scheme. The agreement is particularly subtle in three dimensions where complex answers from localization procedure sometimes arise. We investigate this problem by studying the expectation value of the 1/6 BPS Wilson loop in planar ABJ(M) theory at three loops in perturbation theory. We reproduce the corresponding term in the localization result and argue that it originates entirely from a non-trivial framing of the circular contour. Contrary to pure Chern-Simons theory, we point out that for ABJ(M) the framing phase is a non-trivial function of the couplings and that it potentially receives contributions from vertex-like diagrams. Finally, we briefly discuss the intimate link between the exact framing factor and the Bremsstrahlung function of the 1/2-BPS cusp.
Non-Abelian T-duality and the AdS/CFT correspondence: New N=1 backgrounds
Energy Technology Data Exchange (ETDEWEB)
Itsios, Georgios, E-mail: gitsios@upatras.gr [Department of Engineering Sciences, University of Patras, 26110 Patras (Greece); Department of Mathematics, University of Surrey, Guildford GU2 7XH (United Kingdom); Núñez, Carlos, E-mail: c.nunez@swansea.ac.uk [Swansea University, School of Physical Sciences, Singleton Park, Swansea SA2 8PP (United Kingdom); Sfetsos, Konstadinos, E-mail: k.sfetsos@surrey.ac.uk [Department of Mathematics, University of Surrey, Guildford GU2 7XH (United Kingdom); Department of Engineering Sciences, University of Patras, 26110 Patras (Greece); Thompson, Daniel C., E-mail: dthompson@tena4.vub.ac.be [Theoretische Natuurkunde, Vrije Universiteit Brussel (Belgium); International Solvay Institutes, Pleinlaan 2, B-1050 Brussels (Belgium)
2013-08-01
We consider non-Abelian T-duality on N=1 supergravity backgrounds possessing well understood field theory duals. For the case of D3-branes at the tip of the conifold, we dualise along an SU(2) isometry. The result is a type-IIA geometry whose lift to M-theory is of the type recently proposed by Bah et al. as the dual to certain N=1 SCFT quivers produced by M5-branes wrapping a Riemann surface. In the non-conformal cases we find smooth duals in massive IIA supergravity with a Romans mass naturally quantised. We initiate the interpretation of these geometries in the context of AdS/CFT correspondence. We show that the central charge and the entanglement entropy are left invariant by this dualisation. The backgrounds suggest a form of Seiberg duality in the dual field theories which also exhibit domain walls and confinement in the infrared.
Curved-space classical solutions of a massive supermatrix model
International Nuclear Information System (INIS)
Azuma, Takehiro; Bagnoud, Maxime
2003-01-01
We investigate here a supermatrix model with a mass term and a cubic interaction. It is based on the super Lie algebra osp(1 vertical bar 32,R), which could play a role in the construction of the eleven-dimensional M-theory. This model contains a massive version of the IIB matrix model, where some fields have a tachyonic mass term. Therefore, the trivial vacuum of this theory is unstable. However, this model possesses several classical solutions where these fields build noncommutative curved spaces and these solutions are shown to be energetically more favorable than the trivial vacuum. In particular, we describe in details two cases, the SO(3)xSO(3)xSO(3) (three fuzzy 2-spheres) and the SO(9) (fuzzy 8-sphere) classical backgrounds
Kac-Moody algebras and controlled chaos
International Nuclear Information System (INIS)
Wesley, Daniel H
2007-01-01
Compactification can control chaotic Mixmaster behaviour in gravitational systems with p-form matter: we consider this in light of the connection between supergravity models and Kac-Moody algebras. We show that different compactifications define 'mutations' of the algebras associated with the noncompact theories. We list the algebras obtained in this way, and find novel examples of wall systems determined by Lorentzian (but not hyperbolic) algebras. Cosmological models with a smooth pre-big bang phase require that chaos is absent: we show that compactification alone cannot eliminate chaos in the simplest compactifications of the heterotic string on a Calabi-Yau, or M theory on a manifold of G 2 holonomy. (fast track communication)
Peterson, Candida C.; Wellman, Henry M.; Slaughter, Virginia
2013-01-01
Children aged 3 to 12 years (n=184) with typical development, deafness, autism or Asperger Syndrome took a series of theory-of-mind (ToM) tasks to confirm and extend previous developmental scaling evidence. A new sarcasm task, in the format of Wellman and Liu’s (2004) 5-step ToM scale, added a statistically reliable sixth step to the scale for all diagnostic groups. A key previous finding, divergence in task sequencing for children with autism, was confirmed. Comparisons among diagnostic groups, controlling age and language ability, showed that typical developers mastered the six ToM steps ahead of each of the three disabled groups, with implications for ToM theories. The final (sarcasm) task challenged even nondisabled 9-year-olds, demonstrating the new scale’s sensitivity to post-preschool ToM growth. PMID:22304467
Cosmic evolution in a cyclic universe
International Nuclear Information System (INIS)
Steinhardt, Paul J.; Turok, Neil
2002-01-01
Based on concepts drawn from the ekpyrotic scenario and M theory, we elaborate our recent proposal of a cyclic model of the universe. In this model, the universe undergoes an endless sequence of cosmic epochs which begin with the universe expanding from a 'big bang' and end with the universe contracting to a 'big crunch'. Matching from 'big crunch' to 'big bang' is performed according to the prescription recently proposed with Khoury, Ovrut and Seiberg. The expansion part of the cycle includes a period of radiation and matter domination followed by an extended period of cosmic acceleration at low energies. The cosmic acceleration is crucial in establishing the flat and vacuous initial conditions required for ekpyrosis and for removing the entropy, black holes, and other debris produced in the preceding cycle. By restoring the universe to the same vacuum state before each big crunch, the acceleration ensures that the cycle can repeat and that the cyclic solution is an attractor
Spacetime emergence of the robertson-walker universe from a matrix model.
Erdmenger, Johanna; Meyer, René; Park, Jeong-Hyuck
2007-06-29
Using a novel, string theory-inspired formalism based on a Hamiltonian constraint, we obtain a conformal mechanical system for the spatially flat four-dimensional Robertson-Walker Universe. Depending on parameter choices, this system describes either a relativistic particle in the Robertson-Walker background or metric fluctuations of the Robertson-Walker geometry. Moreover, we derive a tree-level M theory matrix model in this time-dependent background. Imposing the Hamiltonian constraint forces the spacetime geometry to be fuzzy near the big bang, while the classical Robertson-Walker geometry emerges as the Universe expands. From our approach, we also derive the temperature of the Universe interpolating between the radiation and matter dominated eras.
Was the Universe actually radiation dominated prior to nucleosynthesis?
Giblin, John T.; Kane, Gordon; Nesbit, Eva; Watson, Scott; Zhao, Yue
2017-08-01
Maybe not. String theory approaches to both beyond the Standard Model and inflationary model building generically predict the existence of scalars (moduli) that are light compared to the scale of quantum gravity. These moduli become displaced from their low energy minima in the early Universe and lead to a prolonged matter-dominated epoch prior to big bang nucleosynthesis (BBN). In this paper, we examine whether nonperturbative effects such as parametric resonance or tachyonic instabilities can shorten, or even eliminate, the moduli condensate and matter-dominated epoch. Such effects depend crucially on the strength of the couplings, and we find that unless the moduli become strongly coupled, the matter-dominated epoch is unavoidable. In particular, we find that in string and M-theory compactifications where the lightest moduli are near the TeV scale, a matter-dominated epoch will persist until the time of big bang nucleosynthesis.
International Nuclear Information System (INIS)
El Naschie, M.S.
2004-01-01
A careful counting routine of all experimentally confirmed elementary particles plus the theoretically conjectured ones needed for a sound formulation of a mathematically consistent field theory is undertaken within a minimal N=1 super symmetric extension of the standard model of high energy physics. The number arrived at is subsequently linked to certain massless on shell representations connected to the quantized gravity interaction. Finally with the help of number theoretical arguments arising from a rigorous application of the formalism of transfinite Heterotic super string and E-infinity theory, we show that the proposed scheme would lack mathematical consistency and elegant simplicity unless we retain a postulated triplet which is logically identified as the H + , H - and H 0 Higgs particles. Connections to the 11 dimensional M theory and Harari's extended 'sub-quarks' theory is also discussed
Warped Kähler potentials and fluxes
International Nuclear Information System (INIS)
Martucci, Luca
2017-01-01
The four-dimensional effective theory for type IIB warped flux compactifications proposed in https://www.doi.org/10.1007/JHEP03(2015)067 is completed by taking into account the backreaction of the Kähler moduli on the three-form fluxes. The only required modification consists in a flux-dependent contribution to the chiral fields parametrising the Kähler moduli. The resulting supersymmetric effective theory satisfies the no-scale condition and consistently combines previous partial results present in the literature. Similar results hold for M-theory warped compactifications on Calabi-Yau fourfolds, whose effective field theory and Kähler potential are also discussed.
Ganor, Ori J.
2018-02-01
"Curvepole (2,0)-theory" is a deformation of the (2,0)-theory with nonlocal interactions. A curvepole is defined as a two-dimensional generalization of a dipole. It is an object of fixed two-dimensional shape of which the boundary is a charged curve that interacts with a 2-form gauge field. Curvepole theory was previously only defined indirectly via M-theory. Here, we propose a supersymmetric Lagrangian, constructed explicitly up to quartic terms, for an "Abelian" curvepole theory, which is an interacting deformation of the free (2,0) tensor multiplet. This theory contains fields of which the quanta are curvepoles (i.e., fixed-shape strings). Supersymmetry is preserved (at least up to quartic terms) if the shape of the curvepoles is (two-dimensional) planar. This nonlocal six-dimensional quantum field theory may also serve as a UV completion for certain (local) five-dimensional gauge theories.
Guarino, Adolfo
2018-03-01
Supersymmetric {AdS}4, {AdS}2 × Σ 2 and asymptotically AdS4 black hole solutions are studied in the context of non-minimal N=2 supergravity models involving three vector multiplets (STU-model) and Abelian gaugings of the universal hypermultiplet moduli space. Such models correspond to consistent subsectors of the {SO}(p,q) and {ISO}(p,q) gauged maximal supergravities that arise from the reduction of 11D and massive IIA supergravity on {H}^{(p,q)} spaces down to four dimensions. A unified description of all the models is provided in terms of a square-root prepotential and the gauging of a duality-hidden symmetry pair of the universal hypermultiplet. Some aspects of M-theory and massive IIA holography are mentioned in passing.
Topological resolution of gauge theory singularities
Energy Technology Data Exchange (ETDEWEB)
Saracco, Fabio; Tomasiello, Alessandro; Torroba, Gonzalo
2013-08-21
Some gauge theories with Coulomb branches exhibit singularities in perturbation theory, which are usually resolved by nonperturbative physics. In string theory this corresponds to the resolution of timelike singularities near the core of orientifold planes by effects from F or M theory. We propose a new mechanism for resolving Coulomb branch singularities in three-dimensional gauge theories, based on Chern-Simons interactions. This is illustrated in a supersymmetric S U ( 2 ) Yang-Mills-Chern-Simons theory. We calculate the one-loop corrections to the Coulomb branch of this theory and find a result that interpolates smoothly between the high-energy metric (that would exhibit the singularity) and a regular singularity-free low-energy result. We suggest possible applications to singularity resolution in string theory and speculate a relationship to a similar phenomenon for the orientifold six-plane in massive IIA supergravity.
Signals for Non-Cummutative Interactions at Linear Colliders
Energy Technology Data Exchange (ETDEWEB)
Rizzo, Thomas G.
2001-07-23
Recent theoretical results have demonstrated that non-commutative geometries naturally appear within the context of string/M-theory. One consequence of this possibility is that QED takes on a non-abelian nature due to the introduction of 3- and 4-point functions. In addition, each QED vertex acquires a momentum dependent phase factor. We parameterize the effects of non-commutative space-time co-ordinates and show that they lead to observable signatures in several 2 {yields} 2 QED processes in e{sup +}e{sup -} collisions. In particular, we examine pair annihilation, Moller and Bhabha scattering, as well as {gamma}{gamma} {yields} {gamma}{gamma} scattering and show that non-commutative scales of order a TeV can be probed at high energy linear colliders.
On the exceptional generalised Lie derivative for d≥7
International Nuclear Information System (INIS)
Rosabal, J.A.
2015-01-01
In this work we revisit the E_8×ℝ"+ generalised Lie derivative encoding the algebra of diffeomorphisms and gauge transformations of compactifications of M-theory on eight-dimensional manifolds, by extending certain features of the E_7×ℝ"+ one. Compared to its E_d×ℝ"+, d≤7 counterparts, a new term is needed for consistency. However, we find that no compensating parameters need to be introduced, but rather that the new term can be written in terms of the ordinary generalised gauge parameters by means of a connection. This implies that no further degrees of freedom, beyond those of the field content of the E_8 group, are needed to have a well defined theory. We discuss the implications of the structure of the E_8×ℝ"+ generalised transformation on the construction of the d=8 generalised geometry. Finally, we suggest how to lift the generalised Lie derivative to eleven dimensions.
S-folds and 4d N=3 superconformal field theories
Energy Technology Data Exchange (ETDEWEB)
Aharony, Ofer [Department of Particle Physics and Astrophysics,Weizmann Institute of Science, Rehovot 7610001 (Israel); Tachikawa, Yuji [Department of Physics, Faculty of Science,University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan); Kavli Institute for the Physics and Mathematics of the Universe,University of Tokyo, Kashiwa, Chiba 277-8583 (Japan)
2016-06-08
S-folds are generalizations of orientifolds in type IIB string theory, such that the geometric identifications are accompanied by non-trivial S-duality transformations. They were recently used by García-Etxebarria and Regalado to provide the first construction of four dimensional N=3 superconformal theories. In this note, we classify the different variants of these N=3-preserving S-folds, distinguished by an analog of discrete torsion, using both a direct analysis of the different torsion classes and the compactification of the S-folds to three dimensional M-theory backgrounds. Upon adding D3-branes, these variants lead to different classes of N=3 superconformal field theories. We also analyze the holographic duals of these theories, and in particular clarify the role of discrete gauge and global symmetries in holography.
Spectrally selective paint coatings. Preparation and characterization
Energy Technology Data Exchange (ETDEWEB)
Crnjak Orel, Z.C.; Klanjsek Gunde, M. [National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana (Slovenia)
2001-06-01
Preparation and characterization of spectrally selective paint coating for photothermal solar energy conversion are discussed. The applied methods for preparation of paints with described measurements and calculations of black-pigmented coatings were reviewed. The article represents not only possible future applications but also past and current applications of spectrally selective paint coating which are used all over the world since the 1980s. Spectrally selective paint coatings based on combinations of two types of resins, various types of pigments and three types of silica, were prepared. The influence of pigment type and pigment volume concentration (PVC) was studied by applying the Kubelka-Munk (K-M) theory. The relation between the degrees of dispersion and distribution of pigment particles across the paint layer is discussed in terms of K-M coefficients.
Why does inflation start at the top of the hill?
International Nuclear Information System (INIS)
Hawking, S.W.; Hertog, Thomas
2002-01-01
We show why the universe started in an unstable de Sitter state. The quantum origin of our universe implies one must take a 'top down' approach to the problem of initial conditions in cosmology, in which the histories that contribute to the path integral depend on the observable being measured. Using the no boundary proposal to specify the class of histories, we study the quantum cosmological origin of an inflationary universe in theories such as trace anomaly driven inflation in which the effective potential has a local maximum. We find that an expanding universe is most likely to emerge in an unstable de Sitter state, by semiclassical tunneling via a Hawking-Moss instanton. Since the top down view is forced upon us by the quantum nature of the universe, we argue that the approach developed here should still apply when the framework of quantum cosmology will be based on M theory
Nonrelativistic closed string theory
International Nuclear Information System (INIS)
Gomis, Jaume; Ooguri, Hirosi
2001-01-01
We construct a Galilean invariant nongravitational closed string theory whose excitations satisfy a nonrelativistic dispersion relation. This theory can be obtained by taking a consistent low energy limit of any of the conventional string theories, including the heterotic string. We give a finite first order worldsheet Hamiltonian for this theory and show that this string theory has a sensible perturbative expansion, interesting high energy behavior of scattering amplitudes and a Hagedorn transition of the thermal ensemble. The strong coupling duals of the Galilean superstring theories are considered and are shown to be described by an eleven-dimensional Galilean invariant theory of light membrane fluctuations. A new class of Galilean invariant nongravitational theories of light-brane excitations are obtained. We exhibit dual formulations of the strong coupling limits of these Galilean invariant theories and show that they exhibit many of the conventional dualities of M theory in a nonrelativistic setting
Cosmological and theoretical aspects of higher dimensions
International Nuclear Information System (INIS)
Fairbairn, M.
2001-01-01
This thesis deals with various aspects of higher dimensional particle physics theories. First we consider varying constant models where the size of the extra dimensions changes over time. In particular we focus on the effect of a time varying strong coupling constant and its implications for carbon burning in supernovae and the stability of the deuteron. Next we look at cosmological constraints on the size of large extra dimensions which come from the necessity to avoid the over-production of massive Kaluza-Klein modes which might instigate an early matter domination and decrease the age of the universe unacceptably. Finally we consider the possibility of embedding the 2nd Randall-Sundrum model within a supersymmetric theory inspired by M-theory. (author)
Standard model fermions and K(E10
Directory of Open Access Journals (Sweden)
Axel Kleinschmidt
2015-07-01
Full Text Available In recent work [1] it was shown how to rectify Gell-Mann's proposal for identifying the 48 quarks and leptons of the Standard Model with the 48 spin-12 fermions of maximal SO(8 gauged supergravity remaining after the removal of eight Goldstinos, by deforming the residual U(1 symmetry at the SU(3 × U(1 stationary point of N=8 supergravity, so as to also achieve agreement of the electric charge assignments. In this Letter we show that the required deformation, while not in SU(8, does belong to K(E10, the ‘maximal compact’ subgroup of E10 which is a possible candidate symmetry underlying M theory. The incorporation of infinite-dimensional Kac–Moody symmetries of hyperbolic type, apparently unavoidable for the present scheme to work, opens up completely new perspectives on embedding Standard Model physics into a Planck scale theory of quantum gravity.
Effective Gravitational Theories in String Theory and the AdS/CFT Correspondence
DEFF Research Database (Denmark)
Pedersen, Andreas Vigand
an effective theory for higher dimensional extended black holes in a uid/elastic perturbative derivative expansion. Moreover, we show that the approach is quite universal and can be extended to various supergravities. Finally, we consider a new generalization of the method, which allows us to treat (SUGRA...... as low/high spin. As a byproduct of our analysis, we find a new stationary dipole-charged black hole solution on the AdS S backgrounds of type IIB/M-theory. We finally consider, via a double scaling extremal limit, a novel null-wave zero-temperature giant graviton exhibiting a BPS spectrum. Finally......We consider various aspects of effective gravitational theories, including supergravity, within the framework of the blackfold approach. The thesis is naturally split into three parts. In the first part of the thesis, we explore the blackfold approach and explain how it is possible to write down...
Brane Gas-Driven Bulk Expansion as a Precursor Stage to Brane Inflation
International Nuclear Information System (INIS)
Shuhmaher, Natalia; Brandenberger, Robert
2006-01-01
We propose a new way of obtaining slow-roll inflation in the context of higher dimensional models motivated by string and M theory. In our model, all extra spatial dimensions are orbifolded. The initial conditions are taken to be a hot dense bulk brane gas which drives an initial phase of isotropic bulk expansion. This phase ends when a weak potential between the orbifold fixed planes begins to dominate. For a wide class of potentials, a period during which the bulk dimensions decrease sufficiently slowly to lead to slow-roll inflation of the three dimensions parallel to the orbifold fixed planes will result. Once the separation between the orbifold fixed planes becomes of the string scale, a repulsive potential due to string effects takes over and leads to a stabilization of the radion modes. The conversion of bulk branes into radiation during the phase of bulk contraction leads to reheating
Supersymmetry breaking and α'-corrections to flux induced potentials
International Nuclear Information System (INIS)
Becker, Katrin; Becker, Melanie; Haack, Michael; Louis, Jan
2002-01-01
We obtain the vacuum solutions for M-theory compactified on eight-manifolds with non-vanishing four-form flux by analyzing the scalar potential appearing in the three-dimensional theory. Many of these vacua are not supersymmetric and yet have a vanishing three-dimensional cosmological constant.We show that in the context of type-IIB compactifications on Calabi-Yau threefolds with fluxes and external brane sources α'-corrections generate a correction to the supergravity potential proportional to the Euler number of the internal manifold which spoils the no-scale structure appearing in the classical potential. This indicates that α'-corrections may indeed lead to a stabilization of the radial modulus appearing in these compactifications. (author)
Quiver gauge theories and integrable lattice models
International Nuclear Information System (INIS)
Yagi, Junya
2015-01-01
We discuss connections between certain classes of supersymmetric quiver gauge theories and integrable lattice models from the point of view of topological quantum field theories (TQFTs). The relevant classes include 4d N=1 theories known as brane box and brane tilling models, 3d N=2 and 2d N=(2,2) theories obtained from them by compactification, and 2d N=(0,2) theories closely related to these theories. We argue that their supersymmetric indices carry structures of TQFTs equipped with line operators, and as a consequence, are equal to the partition functions of lattice models. The integrability of these models follows from the existence of extra dimension in the TQFTs, which emerges after the theories are embedded in M-theory. The Yang-Baxter equation expresses the invariance of supersymmetric indices under Seiberg duality and its lower-dimensional analogs.
Non-perturbative effects and the refined topological string
Energy Technology Data Exchange (ETDEWEB)
Hatsuda, Yasuyuki [DESY Hamburg (Germany). Theory Group; Tokyo Institute of Technology (Japan). Dept. of Physics; Marino, Marcos [Geneve Univ. (Switzerland). Dept. de Physique Theorique et Section de Mathematiques; Moriyama, Sanefumi [Nagoya Univ. (Japan). Kobayashi Maskawa Inst.; Nagoya Univ. (Japan). Graduate School of Mathematics; Okuyama, Kazumi [Shinshu Univ., Matsumoto, Nagano (Japan). Dept. of Physics
2013-06-15
The partition function of ABJM theory on the three-sphere has non-perturbative corrections due to membrane instantons in the M-theory dual. We show that the full series of membrane instanton corrections is completely determined by the refined topological string on the Calabi-Yau manifold known as local P{sup 1} x P{sup 1}, in the Nekrasov-Shatashvili limit. Our result can be interpreted as a first-principles derivation of the full series of non-perturbative effects for the closed topological string on this Calabi-Yau background. Based on this, we make a proposal for the non-perturbative free energy of topological strings on general, local Calabi-Yau manifolds.
Short distance modifications to Newton's law in SUSY braneworld scenarios
International Nuclear Information System (INIS)
Palma, G.A.
2007-10-01
In braneworld models coming from string theory one generally encounters massless scalar degrees of freedom -moduli- parameterizing the volume of small compact extra-dimensions. Here we discuss the effects of such moduli on Newton's law for a fairly general 5-D supersymmetric braneworld scenario with a bulk scalar field φ.We show that the Newtonian potential describing the gravitational interaction between two bodies localized on the visible brane picks up a non-trivial contribution at short distances that depends on the shape of the superpotential W(φ) of the theory. In particular, we compute this contribution for dilatonic braneworld scenarios W(φ) ∝ e αφ (where a is a constant) and discuss the particular case of 5-D Heterotic M-theory. (orig.)
Extremal static AdS black hole/CFT correspondence in gauged supergravities
International Nuclear Information System (INIS)
Lue, H.; Mei Jianwei; Pope, C.N.; Vazquez-Poritz, Justin F.
2009-01-01
A recently proposed holographic duality allows the Bekenstein-Hawking entropy of extremal rotating black holes to be calculated microscopically, by applying the Cardy formula to the two-dimensional chiral CFTs associated with certain reparameterisations of azimuthal angular coordinates in the solutions. The central charges are proportional to the angular momenta of the black hole, and so the method degenerates in the case of static (non-rotating) black holes. We show that the method can be extended to encompass such charged static extremal AdS black holes by using consistent Kaluza-Klein sphere reduction ansatze to lift them to exact solutions in the low-energy limits of string theory or M-theory, where the electric charges become reinterpreted as angular momenta associated with internal rotations in the reduction sphere. We illustrate the procedure for the examples of extremal charged static AdS black holes in four, five, six and seven dimensions
Theoretical prediction and impact of fundamental electric dipole moments
International Nuclear Information System (INIS)
Ellis, Sebastian A.R.; Kane, Gordon L.
2016-01-01
The predicted Standard Model (SM) electric dipole moments (EDMs) of electrons and quarks are tiny, providing an important window to observe new physics. Theories beyond the SM typically allow relatively large EDMs. The EDMs depend on the relative phases of terms in the effective Lagrangian of the extended theory, which are generally unknown. Underlying theories, such as string/M-theories compactified to four dimensions, could predict the phases and thus EDMs in the resulting supersymmetric (SUSY) theory. Earlier one of us, with collaborators, made such a prediction and found, unexpectedly, that the phases were predicted to be zero at tree level in the theory at the unification or string scale ∼O(10 16 GeV). Electroweak (EW) scale EDMs still arise via running from the high scale, and depend only on the SM Yukawa couplings that also give the CKM phase. Here we extend the earlier work by studying the dependence of the low scale EDMs on the constrained but not fully known fundamental Yukawa couplings. The dominant contribution is from two loop diagrams and is not sensitive to the choice of Yukawa texture. The electron EDM should not be found to be larger than about 5×10 −30 e cm, and the neutron EDM should not be larger than about 5×10 −29 e cm. These values are quite a bit smaller than the reported predictions from Split SUSY and typical effective theories, but much larger than the Standard Model prediction. Also, since models with random phases typically give much larger EDMs, it is a significant testable prediction of compactified M-theory that the EDMs should not be above these upper limits. The actual EDMs can be below the limits, so once they are measured they could provide new insight into the fundamental Yukawa couplings of leptons and quarks. We comment also on the role of strong CP violation. EDMs probe fundamental physics near the Planck scale.
Tan, Meng-Chwan
2013-07-01
In part I, we extend our analysis in [arXiv:0807.1107], and show that a mathematically conjectured geometric Langlands duality for complex surfaces in [1], and its generalizations — which relate some cohomology of the moduli space of certain ("ramified") G-instantons to the integrable representations of the Langlands dual of certain affine (sub) G-algebras, where G is any compact Lie group — can be derived, purely physically, from the principle that the spacetime BPS spectra of string-dual M-theory compactifications ought to be equivalent. In part II, to the setup in part I, we introduce Omega-deformation via fluxbranes and add half-BPS boundary defects via M9-branes, and show that the celebrated AGT correspondence in [2, 3], and its generalizations — which essentially relate, among other things, some equivariant cohomology of the moduli space of certain ("ramified") G-instantons to the integrable representations of the Langlands dual of certain affine -algebras — can likewise be derived from the principle that the spacetime BPS spectra of string-dual M-theory compactifications ought to be equivalent. In part III, we consider various limits of our setup in part II, and connect our story to chiral fermions and integrable systems. Among other things, we derive the NekrasovOkounkov conjecture in [4] — which relates the topological string limit of the dual Nekrasov partition function for pure G to the integrable representations of the Langlands dual of an affine G-algebra — and also demonstrate that the Nekrasov-Shatashvili limit of the "fullyramified" Nekrasov instanton partition function for pure G is a simultaneous eigenfunction of the quantum Toda Hamiltonians associated with the Langlands dual of an affine G-algebra. Via the case with matter, we also make contact with Hitchin systems and the "ramified" geometric Langlands correspondence for curves.
Three-dimensional N=6 superconformal field theories and their membrane dynamics
International Nuclear Information System (INIS)
Berenstein, David; Trancanelli, Diego
2008-01-01
We analyze several aspects of the recent construction of three-dimensional conformal gauge theories by Aharony et al. in various regimes. We pay special attention to understanding how the M-theory geometry and interpretation can be extracted from the analysis of the field theory. We revisit the calculations of the moduli space of vacua and the complete characterization of chiral ring operators by analyzing the field theory compactified on a 2-sphere. We show that many of the states dual to these operators can be interpreted as D-brane states in the weak-coupling limit. Also, various features of the dual AdS geometry can be obtained by performing a strong coupling expansion around moduli space configurations, even though one is not taking the planar expansion. In particular, we show that at strong coupling the corresponding weak-coupling D-brane states of the chiral ring localize on particular submanifolds of the dual geometry that match the M-theory interpretation. We also study the massive spectrum of fields in the moduli space. We use this to investigate the dispersion relation of giant magnons from the field theory point of view. Our analysis predicts the exact functional form of the dispersion relation as a function of the world sheet momentum, independently of integrability assumptions, but not the exact form with respect to the 't Hooft coupling. We also get the dispersion relation of bound states of giant magnons from first principles, providing evidence for the full integrability of the corresponding spin chain model at strong 't Hooft coupling.
Theoretical prediction and impact of fundamental electric dipole moments
Energy Technology Data Exchange (ETDEWEB)
Ellis, Sebastian A.R.; Kane, Gordon L. [Michigan Center for Theoretical Physics (MCTP),Department of Physics, University of Michigan,Ann Arbor, MI 48109 (United States)
2016-01-13
The predicted Standard Model (SM) electric dipole moments (EDMs) of electrons and quarks are tiny, providing an important window to observe new physics. Theories beyond the SM typically allow relatively large EDMs. The EDMs depend on the relative phases of terms in the effective Lagrangian of the extended theory, which are generally unknown. Underlying theories, such as string/M-theories compactified to four dimensions, could predict the phases and thus EDMs in the resulting supersymmetric (SUSY) theory. Earlier one of us, with collaborators, made such a prediction and found, unexpectedly, that the phases were predicted to be zero at tree level in the theory at the unification or string scale ∼O(10{sup 16} GeV). Electroweak (EW) scale EDMs still arise via running from the high scale, and depend only on the SM Yukawa couplings that also give the CKM phase. Here we extend the earlier work by studying the dependence of the low scale EDMs on the constrained but not fully known fundamental Yukawa couplings. The dominant contribution is from two loop diagrams and is not sensitive to the choice of Yukawa texture. The electron EDM should not be found to be larger than about 5×10{sup −30}e cm, and the neutron EDM should not be larger than about 5×10{sup −29}e cm. These values are quite a bit smaller than the reported predictions from Split SUSY and typical effective theories, but much larger than the Standard Model prediction. Also, since models with random phases typically give much larger EDMs, it is a significant testable prediction of compactified M-theory that the EDMs should not be above these upper limits. The actual EDMs can be below the limits, so once they are measured they could provide new insight into the fundamental Yukawa couplings of leptons and quarks. We comment also on the role of strong CP violation. EDMs probe fundamental physics near the Planck scale.
The Future of Theoretical Physics and Cosmology
Gibbons, G. W.; Shellard, E. P. S.; Rankin, S. J.
2009-08-01
Preface; List of contributors; 1. Introduction; Part I. Popular Symposium: 2. Our complex cosmos and its future Martin J. Rees; 3. Theories of everything and Hawking's wave function of the Universe James B. Hartle; 4. The problem of space-time singularities: implications for quantum gravity? Roger Penrose; 5. Warping spacetime Kip Thorne; 6. 60 years in a nutshell Stephen W. Hawking; Part II. Spacetime Singularities: 7. Cosmological perturbations and singularities George F. R. Ellis; 8. The quantum physics of chronology protection Matt Visser; 9. Energy dominance and the Hawking-Ellis vacuum conservation theorem Brandon Carter; 10. On the instability of extra space dimensions Roger Penrose; Part III. Black Holes: 11. Black hole uniqueness and the inner horizon stability problem Werner Israel; 12. Black holes in the real universe and their prospects as probes of relativistic gravity Martin J. Rees; 13. Primordial black holes Bernard Carr; 14. Black hole pair creation Simon F. Ross; 15. Black holes as accelerators Steven Giddings; Part IV. Hawking Radiation: 16. Black holes and string theory Malcolm Perry; 17. M theory and black hole quantum mechanics Joe Polchinski; 18. Playing with black strings Gary Horowitz; 19. Twenty years of debate with Stephen Leonard Susskind; Part V. Quantum Gravity: 20. Euclidean quantum gravity: the view from 2002 Gary Gibbons; 21. Zeta functions, anomalies and stable branes Ian Moss; 22. Some reflections on the status of conventional quantum theory when applied to quantum gravity Chris Isham; 23. Quantum geometry and its ramifications Abhay Ashtekar; 24. Topology change in quantum gravity Fay Dowker; Part VI. M Theory and Beyond: 25. The past and future of string theory Edward Witten; 26. String theory David Gross; 27. A brief description of string theory Michael Green; 28. The story of M Paul Townsend; 29. Gauged supergravity and holographic field theory Nick Warner; 30. 57 varieties in a NUTshell Chris Pope; Part VII. de Sitter Space
Effective actions for F-theory compactifications and tensor theories
International Nuclear Information System (INIS)
Bonetti, Federico
2014-01-01
In this thesis we study the low-energy effective dynamics emerging from a class of F-theory compactifications in four and six dimensions. We also investigate six-dimensional supersymmetric quantum field theories with self-dual tensors, motivated by the problem of describing the long-wavelength regime of a stack of M5-branes in M-theory. These setups share interesting common features. They both constitute examples of intrinsically non-perturbative physics. On the one hand, in the context of F-theory the non-perturbative character is encoded in the geometric formulation of this class of string vacua, which allows the complexified string coupling to vary in space. On the other hand, the dynamics of a stack of multiple M5-branes flows in the infrared to a novel kind of superconformal field theories in six dimensions - commonly referred to as (2,0) theories - that are expected to possess no perturbative weakly coupled regime and have resisted a complete understanding so far. In particular, no Lagrangian description is known for these models. The strategy we employ to address these two problems is also analogous. A recurring Leitmotif of our work is a transdimensional treatment of the system under examination: in order to extract information about dynamics in d dimensions we consider a (d-1)-dimensional setup. As far as F-theory compactifications are concerned, this is a consequence of the duality between M-theory and F-theory, which constitutes our main tool in the derivation of the effective action of F-theory compactifications. We apply it to six-dimensional F-theory vacua, obtained by taking the internal space to be an elliptically fibered Calabi-Yau threefold, but we also employ it to explore a novel kind of F-theory constructions in four dimensions based on manifolds with Spin(7) holonomy. With reference to six-dimensional (2,0) theories, the transdimensional character of our approach relies in the idea of studying these theories in five dimensions. Indeed, we
Geometric symmetries and topological terms in F-theory and field theory
Energy Technology Data Exchange (ETDEWEB)
Kapfer, Andreas
2016-08-25
In this thesis we investigate topological aspects and arithmetic structures in quantum field theory and string theory. Particular focus is put on consistent truncations of supergravity and compactifications of F-theory. The first part treats settings of supersymmetry breaking in five dimensions. We focus on an N=4 to N=2 breaking in gauged supergravity. For certain classes of embedding tensors we can analyze the theory around the vacuum to a great extent. Importantly, one-loop corrections to Chern-Simons terms are generically induced which are independent of the supersymmetry-breaking scale. We investigate concrete examples of consistent truncations of supergravity and M-theory which show this N=4 to N=2 breaking pattern in five dimensions. In particular, we analyze necessary conditions for these consistent truncations to be used as effective theories for phenomenology by demanding consistency of the scale-independent corrections to Chern-Simons couplings. The second part is devoted to the study of anomalies and large gauge transformations in circle-reduced gauge theories and F-theory. We consider four- and six-dimensional matter-coupled gauge theories on the circle and classify all large gauge transformations that preserve the boundary conditions of the matter fields. Enforcing that they act consistently on one-loop Chern-Simons couplings in three and five dimensions explicitly yields all higher-dimensional gauge anomaly cancelation conditions. In the context of F-theory compactifications we identify the classified large gauge transformations along the circle with arithmetic structures on elliptically fibered Calabi-Yau manifolds via the dual M-theory setting. Integer Abelian large gauge transformations correspond to free basis shifts in the Mordell-Weil lattice of rational sections while special fractional non-Abelian large gauge transformations are matched to torsional shifts in the Mordell-Weil group. For integer non-Abelian large gauge transformations we
Emergence and expansion of cosmic space as due to M0-branes
Energy Technology Data Exchange (ETDEWEB)
Sepehri, Alireza, E-mail: alireza.sepehri@uk.ac.ir [Faculty of Physics, Shahid Bahonar University, P.O. Box 76175, Kerman (Iran, Islamic Republic of); Research Institute for Astronomy and Astrophysics of Maragha (RIAAM), P.O. Box 55134-441, Maragha (Iran, Islamic Republic of); Setare, Mohammad Reza, E-mail: rezakord@ipm.ir [Department of Science, University of Kurdistan, Campus of Bijar, Bijar (Iran, Islamic Republic of); Capozziello, Salvatore, E-mail: capozziello@na.infn.it [Dipartimento di Fisica, Universita di Napoli Federico II, 80126, Naples (Italy); INFN Sez. di Napoli, Compl. Univ. di Monte S. Angelo, Edificio G, 80126, Naples (Italy); Gran Sasso Science Institute (INFN), Viale F. Crispi, 7, 67100, L’Aquila (Italy)
2015-12-29
Recently, Padmanabhan discussed that the difference between the number of degrees of freedom on the boundary surface and the number of degrees of freedom in a bulk region causes the accelerated expansion of the universe. The main question arising is: what is the origin of this inequality between the surface degrees of freedom and the bulk degrees of freedom? We answer this question in M-theory. In our model, first M0-branes are compactified on one circle and ND0-branes are created. Then ND0-branes join each other, grow, and form one D5-branes. Next, the D5-brane is compactified on two circles and our universe’s D3-brane, two D1-branes and some extra energies are produced. After that, one of the D1-branes, which is closer to the universe’s brane, gives its energy into it, and this leads to an increase in the difference between the numbers of degrees of freedom and the occurring inflation era. With the disappearance of this D1-brane, the number of degrees of freedom of boundary surface and bulk region become equal and inflation ends. At this stage, extra energies that are produced due to the compactification cause an expansion of the universe and deceleration epoch. Finally, another D1-brane dissolves in our universe’s brane, leads to an inequality between degrees of freedom, and there occurs a new phase of acceleration.
Dilaton dynamics from production of tensionless membranes
International Nuclear Information System (INIS)
Cremonini, Sera; Watson, Scott
2006-01-01
In this paper we consider classical and quantum corrections to cosmological solutions of 11D supergravity (SUGRA) coming from dynamics of membrane states. We first consider the supermembrane spectrum following the approach of Russo and Tseytlin for consistent quantization. We calculate the production rate of Bogomol'nyi-Prasad-Sommerfield (BPS) membrane bound states in a cosmological background and find that such effects are generically suppressed by the Planck scale, as expected. However, for a modified brane spectrum possessing enhanced symmetry, production can be finite and significant. We stress that this effect could not be anticipated given only a knowledge of the low-energy effective theory. Once on shell, inclusion of these states leads to an attractive force pulling the dilaton towards a fixed point of S-duality, namely g s =1. Although the SUGRA description breaks down in this regime, inclusion of the enhanced states suggests that the center of M-theory moduli space is a dynamical attractor. Moreover, our results seem to suggest that string dynamics does indeed favor a vacuum near fixed points of duality
Half-maximal supersymmetry from exceptional field theory
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Malek, Emanuel [Arnold Sommerfeld Center for Theoretical Physics, Department fuer Physik, Ludwig-Maximilians-Universitaet Muenchen (Germany)
2017-10-15
We study D ≥ 4-dimensional half-maximal flux backgrounds using exceptional field theory. We define the relevant generalised structures and also find the integrability conditions which give warped half-maximal Minkowski{sub D} and AdS{sub D} vacua. We then show how to obtain consistent truncations of type II / 11-dimensional SUGRA which break half the supersymmetry. Such truncations can be defined on backgrounds admitting exceptional generalised SO(d - 1 - N) structures, where d = 11 - D, and N is the number of vector multiplets obtained in the lower-dimensional theory. Our procedure yields the most general embedding tensors satisfying the linear constraint of half-maximal gauged SUGRA. We use this to prove that all D ≥ 4 half-maximal warped AdS{sub D} and Minkowski{sub D} vacua of type II / 11-dimensional SUGRA admit a consistent truncation keeping only the gravitational supermultiplet. We also show to obtain heterotic double field theory from exceptional field theory and comment on the M-theory / heterotic duality. In five dimensions, we find a new SO(5, N) double field theory with a (6 + N)-dimensional extended space. Its section condition has one solution corresponding to 10-dimensional N = 1 supergravity and another yielding six-dimensional N = (2, 0) SUGRA. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
On discrete symmetries and torsion homology in F-theory
Energy Technology Data Exchange (ETDEWEB)
Mayrhofer, Christoph [Arnold-Sommerfeld-Center, Ludwig-Maximilians-Universität München,München (Germany); Palti, Eran; Till, Oskar; Weigand, Timo [Institut für Theoretische Physik, Ruprecht-Karls-Universität Heidelberg,Heidelberg (Germany)
2015-06-04
We study the relation between discrete gauge symmetries in F-theory compactifications and torsion homology on the associated Calabi-Yau manifold. Focusing on the simplest example of a ℤ{sub 2} symmetry, we show that there are two physically distinct ways that such a discrete gauge symmetry can arise. First, compactifications of M-Theory on Calabi-Yau threefolds which support a genus-one fibration with a bi-section are known to be dual to six-dimensional F-theory vacua with a ℤ{sub 2} gauge symmetry. We show that the resulting five-dimensional theories do not have a ℤ{sub 2} symmetry but that the latter emerges only in the F-theory decompactification limit. Accordingly the genus-one fibred Calabi-Yau manifolds do not exhibit torsion in homology. Associated to the bi-section fibration is a Jacobian fibration which does support a section. Compactifying on these related but distinct varieties does lead to a ℤ{sub 2} symmetry in five dimensions and, accordingly, we find explicitly an associated torsion cycle. We identify the expected particle and membrane system of the discrete symmetry in terms of wrapped M2 and M5 branes and present a field-theory description of the physics for both cases in terms of circle reductions of six-dimensional theories. Our results and methods generalise straightforwardly to larger discrete symmetries and to four-dimensional compactifications.
Energy Technology Data Exchange (ETDEWEB)
NONE
2004-07-01
Full text: We review the realization of gravity trapping on braneworlds modeled by domain walls solutions in fundamental string/M-theory. Particularly, we are interested on effective five-dimensional theories obtained through compactifications of ten/eleven-dimensional theories down to five dimensions. Such compactifications produce an effective gauge supergravity theory. Some five-dimensional gauged supergravities impose severe restrictions on the superpotential. Those restrictions usually concern a very special geometry on the superpotential manifold. In such theories there are metric warp factor solutions that grow exponentially on either side of the wall. These solutions are not relevant for the trapping of gravity; instead, they are relevant for for AdS/CFT correspondence. This can be seen by exploring the supersymmetric flow equations (renormalization group (RG) equations). Expanding the RG equations around supersymmetric minima and using the restriction imposed on the superpotential we find ultraviolet (UV) fixed points. This is good for Ads/Cfta but not relevant for trapping gravity. We complete the discussion by commenting on some other special geometries that can support gravity trapping. (author)
International Nuclear Information System (INIS)
Brito, Francisco A.
2004-01-01
Full text: We review the realization of gravity trapping on braneworlds modeled by domain walls solutions in fundamental string/M-theory. Particularly, we are interested on effective five-dimensional theories obtained through compactifications of ten/eleven-dimensional theories down to five dimensions. Such compactifications produce an effective gauge supergravity theory. Some five-dimensional gauged supergravities impose severe restrictions on the superpotential. Those restrictions usually concern a very special geometry on the superpotential manifold. In such theories there are metric warp factor solutions that grow exponentially on either side of the wall. These solutions are not relevant for the trapping of gravity; instead, they are relevant for for AdS/CFT correspondence. This can be seen by exploring the supersymmetric flow equations (renormalization group (RG) equations). Expanding the RG equations around supersymmetric minima and using the restriction imposed on the superpotential we find ultraviolet (UV) fixed points. This is good for Ads/Cfta but not relevant for trapping gravity. We complete the discussion by commenting on some other special geometries that can support gravity trapping. (author)
Can renormalization group flow end in a Big Mess?
International Nuclear Information System (INIS)
Morozov, Alexei; Niemi, Antti J.
2003-01-01
The field theoretical renormalization group equations have many common features with the equations of dynamical systems. In particular, the manner how Callan-Symanzik equation ensures the independence of a theory from its subtraction point is reminiscent of self-similarity in autonomous flows towards attractors. Motivated by such analogies we propose that besides isolated fixed points, the couplings in a renormalizable field theory may also flow towards more general, even fractal attractors. This could lead to Big Mess scenarios in applications to multiphase systems, from spin-glasses and neural networks to fundamental string (M?) theory. We consider various general aspects of such chaotic flows. We argue that they pose no obvious contradictions with the known properties of effective actions, the existence of dissipative Lyapunov functions, and even the strong version of the c-theorem. We also explain the difficulties encountered when constructing effective actions with chaotic renormalization group flows and observe that they have many common virtues with realistic field theory effective actions. We conclude that if chaotic renormalization group flows are to be excluded, conceptually novel no-go theorems must be developed
Confinement and strings in MQCD
International Nuclear Information System (INIS)
Hanany, A.; Strassler, M.J.; Zaffaroni, A.
1998-01-01
We study aspects of confinement in the M-theory fivebrane version of QCD (MQCD). We show heavy quarks are confined in hadrons (which take the form of membrane-fivebrane bound states) for N=1 and softly broken N=2 SU(N) MQCD. We explore and clarify the transition from the exotic physics of the latter to the standard physics of the former. In particular, the many strings and quark-antiquark mesons found in N=2 field theory by Douglas and Shenker are reproduced. It is seen that in the N=1 limit all but one such meson disappears while all of the strings survive. The strings of softly broken N=2, N=1, and even non-supersymmetric SU(N) MQCD have a common ratio for their tensions as a function of the amount of flux they carry. We also comment on the almost BPS properties of the Douglas-Shenker strings and discuss the brane picture for monopole confinement on N=2 QCD Higgs branches. (orig.)
Energy conditions in modified Gauss-Bonnet gravity
International Nuclear Information System (INIS)
Garcia, Nadiezhda Montelongo; Harko, Tiberiu; Lobo, Francisco S. N.; Mimoso, Jose P.
2011-01-01
In considering alternative higher-order gravity theories, one is liable to be motivated in pursuing models consistent and inspired by several candidates of a fundamental theory of quantum gravity. Indeed, motivations from string/M theory predict that scalar field couplings with the Gauss-Bonnet invariant, G, are important in the appearance of nonsingular early time cosmologies. In this work, we discuss the viability of an interesting alternative gravitational theory, namely, modified Gauss-Bonnet gravity or f(G) gravity. We consider specific realistic forms of f(G) analyzed in the literature that account for the late-time cosmic acceleration and that have been found to cure the finite-time future singularities present in the dark energy models. We present the general inequalities imposed by the energy conditions and use the recent estimated values of the Hubble, deceleration, jerk and snap parameters to examine the viability of the above-mentioned forms of f(G) imposed by the weak energy condition.
International Nuclear Information System (INIS)
Ketov, S.V.
1996-09-01
Taking the (2,2) strings as a starting point, we discuss the equivalent self-dual field theories and analyze their symmetry structure in 2+2 dimensions from the viewpoint of string/membrane unification. Requiring the 'Lorentz' invariance and supersymmetry in the (2,2) string target space leads to an extension of the (2,2) string theory to a theory of 2+2 dimensional supermembranes (M-branes) propagating in a higher dimensional target space. The origin of the hidden target space dimensions of the M-brane is related to the maximally extended supersymmetry implied by the 'Lorentz' covariance and dimensional reasons. The Kaehler-Chern-Simons-type action describing the self-dual gravity in 2+2 dimensions is proposed. Its maximal supersymmetrization (of the Green-Schwarz-type) naturally leads to the 2+10 (or higher) dimensions for the M-brane target space. The proposed OSp(32 vertical stroke 1) supersymmetric action gives the pre-geometrical description of M-branes, which may be useful for a fundamental formulation of F and M theory. (orig.)
Cosmological solutions, p-branes, and the Wheeler-DeWitt equation
International Nuclear Information System (INIS)
Lue, H.; Maharana, J.; Maharana, J.; Mukherji, S.; Pope, C.N.; Pope, C.N.
1998-01-01
The low energy effective actions which arise from string theory or M-theory are considered in the cosmological context, where the graviton, dilaton and antisymmetric tensor field strengths depend only on time. We show that previous results can be extended to include cosmological solutions that are related to the E N Toda equations. The solutions of the Wheeler-DeWitt equation in minisuperspace are obtained for some of the simpler cosmological models by introducing intertwining operators that generate canonical transformations which map the theories into free theories. We study the cosmological properties of these solutions, and also briefly discuss generalized Brans-Dicke models in our framework. The cosmological models are closely related to p-brane solitons, which we discuss in the context of the E N Toda equations. We give the explicit solutions for extremal multi-charge (D-3)-branes in the truncated system described by the D 4 =O(4,4) Toda equations. copyright 1998 The American Physical Society
Emergence and expansion of cosmic space as due to M0-branes
International Nuclear Information System (INIS)
Sepehri, Alireza; Setare, Mohammad Reza; Capozziello, Salvatore
2015-01-01
Recently, Padmanabhan discussed that the difference between the number of degrees of freedom on the boundary surface and the number of degrees of freedom in a bulk region causes the accelerated expansion of the universe. The main question arising is: what is the origin of this inequality between the surface degrees of freedom and the bulk degrees of freedom? We answer this question in M-theory. In our model, first M0-branes are compactified on one circle and ND0-branes are created. Then ND0-branes join each other, grow, and form one D5-branes. Next, the D5-brane is compactified on two circles and our universe’s D3-brane, two D1-branes and some extra energies are produced. After that, one of the D1-branes, which is closer to the universe’s brane, gives its energy into it, and this leads to an increase in the difference between the numbers of degrees of freedom and the occurring inflation era. With the disappearance of this D1-brane, the number of degrees of freedom of boundary surface and bulk region become equal and inflation ends. At this stage, extra energies that are produced due to the compactification cause an expansion of the universe and deceleration epoch. Finally, another D1-brane dissolves in our universe’s brane, leads to an inequality between degrees of freedom, and there occurs a new phase of acceleration
Shock and magnetosonic waves in a Mather-type plasma focus
International Nuclear Information System (INIS)
Gerdin, G.; Venneri, F.; Boulais, K.
1986-01-01
A fast streak camera has been used to measure the speeds of the axially propagating transverse ionization wave (or rundown phase), the radial collapse, and what appears to be a magnetosonic compression wave propagating along the pinch. The current flowing in the moving current sheath was measured by means of a magnetic probe placed between the coaxial electrodes. The magnetic probe is necessary to determine the pinch current since the device current does not always entirely flow in the current sheath (CS). The CS current was varied from about 200 to 800 kA in the experiments reported here at a static fill of 3 Torr of deuterium. All three velocities were found to be linear with the CS current as predicted from simple models with less than a 10% uncertainty in the least squares slope. The axial or rundown speed was found to be consistent with the constant speed model of v/sub AX/ ≅ v/sub A//√2 where v/sub A/ is the Alfven speed at the surface of the inner conductor. The velocity of the radial collapse was compared with a 4th Order Runge-Kutta solution to the snowplow model or 'M' theory and the agreement was not as good. The magnetosonic scaling with current at constant fill pressure is consistent with a constant mass per unit length being swept up by the snowplow and representing about 1/4 of the original fill gas mass per unit length over the center electrode
Anomaly cancelation in field theory and F-theory on a circle
International Nuclear Information System (INIS)
Grimm, Thomas W.; Kapfer, Andreas
2016-01-01
We study the manifestation of local gauge anomalies of four- and six-dimensional field theories in the lower-dimensional Kaluza-Klein theory obtained after circle compactification. We identify a convenient set of transformations acting on the whole tower of massless and massive states and investigate their action on the low-energy effective theories in the Coulomb branch. The maps employ higher-dimensional large gauge transformations and precisely yield the anomaly cancelation conditions when acting on the one-loop induced Chern-Simons terms in the three- and five-dimensional effective theory. The arising symmetries are argued to play a key role in the study of the M-theory to F-theory limit on Calabi-Yau manifolds. For example, using the fact that all fully resolved F-theory geometries inducing multiple Abelian gauge groups or non-Abelian groups admit a certain set of symmetries, we are able to generally show the cancelation of pure Abelian or pure non-Abelian anomalies in these models.
Supersymmetric AdS{sub 2} x Σ{sub 2} solutions from tri-sasakian truncation
Energy Technology Data Exchange (ETDEWEB)
Karndumri, Parinya [Chulalongkorn University, String Theory and Supergravity Group, Department of Physics, Faculty of Science, Bangkok (Thailand)
2017-10-15
A class of AdS{sub 2} x Σ{sub 2}, with Σ{sub 2} being a two-sphere or a hyperbolic space, solutions within four-dimensional N = 4 gauged supergravity coupled to three-vector multiplets with dyonic gauging is identified. The gauged supergravity has a non-semisimple SO(3) x (T{sup 3}, T{sup 3}) gauge group and can be obtained from a consistent truncation of 11-dimensional supergravity on a tri-sasakian manifold. The maximally symmetric vacua contain AdS{sub 4} geometries with N = 1, 3 supersymmetry corresponding to N = 1 and N = 3 superconformal field theories (SCFTs) in three dimensions. We find supersymmetric solutions of the form AdS{sub 2} x Σ{sub 2} preserving two supercharges. These solutions describe twisted compactifications of the dual N = 1 and N = 3 SCFTs and should arise as near horizon geometries of dyonic black holes in asymptotically AdS{sub 4} space-time. Most solutions AdS{sub 2} x Σ{sub 2} geometries with known M-theory origin. (orig.)
Open string T-duality in double space
Energy Technology Data Exchange (ETDEWEB)
Sazdovic, B. [University of Belgrade, Institute of Physics, Belgrade (Serbia)
2017-09-15
The role of double space is essential in the new interpretation of T-duality and consequently in an attempt to construct M-theory. The case of the open string is missing in such an approach because until now there has been no appropriate formulation of open string T-duality. In the previous paper (Sazdovic, From geometry to non-geometry via T-duality, arXiv:1606.01938, 2017), we showed how to introduce vector gauge fields A{sup N}{sub a} and A{sup D}{sub i} at the end-points of an open string in order to enable open string invariance under local gauge transformations of the Kalb-Ramond field and its T-dual ''restricted general coordinate transformations''. We demonstrated that gauge fields A{sup N}{sub a} and A{sup D}{sub i} are T-dual to each other. In the present article we prove that all above results can be interpreted as coordinate permutations in double space. (orig.)
Static BPS black holes in AdS{sub 4} with general dyonic charges
Energy Technology Data Exchange (ETDEWEB)
Halmagyi, Nick [Sorbonne Universités, UPMC Paris 06, UMR 7589, LPTHE,75005, Paris (France); CNRS, UMR 7589, LPTHE,75005, Paris (France)
2015-03-06
We complete the study of static BPS, asymptotically AdS{sub 4} black holes within N=2 FI-gauged supergravity and where the scalar manifold is a symmetric very special Kähler manifold. We find the analytic form for the general solution to the BPS equations, the horizon appears as a double root of a particular quartic polynomial whereas in previous work this quartic polynomial further factored into a pair of double roots. A new and distinguishing feature of our solutions is that the phase of the supersymmetry parameter varies throughout the black hole. The general solution has 2n{sub v} independent parameters; there are two algebraic constraints on 2n{sub v}+2 charges, matching our previous analysis on BPS solutions of the form AdS{sub 2}×Σ{sub g}. As a consequence we have proved that every BPS geometry of this form can arise as the horizon geometry of a BPS AdS{sub 4} black hole. When specialized to the STU-model our solutions uplift to M-theory and describe a stack of M2-branes wrapped on a Riemman surface in a Calabi-Yau fivefold with internal angular momentum.
Holographic Protection of Chronology in Universes of the Godel Type
Energy Technology Data Exchange (ETDEWEB)
Boyda, Edward; Ganguli, Surya; Horava, Petr; Varadarajan, Uday
2002-12-07
We analyze the structure of supersymmetric Godel-like cosmological solutions of string theory. Just as the original four-dimensional Godel universe, these solutions represent rotating, topologically trivial cosmologies with a homogeneous metric and closed timelike curves. First we focus on"phenomenological" aspects of holography, and identify the preferred holographic screens associated with inertial comoving observers in Godel universes. We find that holography can serve as a chronology protection agency: The closed timelike curves are either hidden behind the holographic screen, or broken by it into causal pieces. In fact, holography in Godel universes has many features in common with de Sitter space, suggesting that Godel universes could represent a supersymmetric laboratory for addressing the conceptual puzzles of de Sitter holography. Then we initiate the investigation of"microscopic" aspects of holography of Godel universes in string theory. We show that Godel universes are T-dual to pp-waves, and use this fact to generate new Godel-like solutions of string and M-theory by T-dualizing known supersymmetric pp-wave solutions.
Mao, Wei-Chung; Chen, Li-Fen; Chi, Chia-Hsing; Lin, Ching-Hung; Kao, Yu-Chen; Hsu, Wen-Yau; Lane, Hsien-Yuan; Hsieh, Jen-Chuen
2016-09-30
Schizophrenia is an illness that impairs a person's social cognition. The Mayer Salovey Caruso Emotional Intelligence Test (MSCEIT) is the most well-known test used to measure emotional intelligence (EI), which is a major component of social cognition. Given the absence of EI ability-based scales adapted to Chinese speakers, we translated the MSCEIT into a Traditional Chinese version (MSCEIT-TC) and validated this scale for use in schizophrenia studies. The specific aims were to validate the MSCEIT-TC, to develop a norm for the MSCEIT-TC, and use this norm to explore the EI performance of schizophrenic individuals. We included in our study seven hundred twenty-eight healthy controls and seventy-six individuals with schizophrenia. The results suggest that the MSCEIT-TC is reliable and valid when assessing EI. The results showed good discrimination and validity when comparing the two study groups. Impairment was the greatest for two branches Understanding and Managing Emotions, which implies that the deficits of schizophrenia individuals involve ToM (theory of mind) tasks. Deficits involving the negative scale of schizophrenia was related to impaired performance when the MSCEIT-TC was used (in branch 2, 3, 4, and the area Strategic). Our findings suggest that the MSCEIT-TC can be used for emotional studies in healthy Chinese and in clinical setting for investigating schizophrenic individuals. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Gauge backgrounds and zero-mode counting in F-theory
Bies, Martin; Mayrhofer, Christoph; Weigand, Timo
2017-11-01
Computing the exact spectrum of charged massless matter is a crucial step towards understanding the effective field theory describing F-theory vacua in four dimensions. In this work we further develop a coherent framework to determine the charged massless matter in F-theory compactified on elliptic fourfolds, and demonstrate its application in a concrete example. The gauge background is represented, via duality with M-theory, by algebraic cycles modulo rational equivalence. Intersection theory within the Chow ring allows us to extract coherent sheaves on the base of the elliptic fibration whose cohomology groups encode the charged zero-mode spectrum. The dimensions of these cohomology groups are computed with the help of modern techniques from algebraic geometry, which we implement in the software gap. We exemplify this approach in models with an Abelian and non-Abelian gauge group and observe jumps in the exact massless spectrum as the complex structure moduli are varied. An extended mathematical appendix gives a self-contained introduction to the algebro-geometric concepts underlying our framework.
The large N limit of superconformal field theories and supergravity
International Nuclear Information System (INIS)
Maldacena, J.
1999-01-01
We show that the large N limit of certain conformal field theories in various dimensions include in their Hilbert space a sector describing supergravity on the product of Anti-deSitter spacetimes, spheres and other compact manifolds. This is shown by taking some branes in the full M/string theory and then taking a low energy limit where the field theory on the brane decouples from the bulk. We observe that, in this limit, we can still trust the near horizon geometry for large N. The enhanced supersymmetries of the near horizon geometry correspond to the extra supersymmetry generators present in the superconformal group (as opposed to just the super-Poincare group). The close-quote t Hooft limit of 3+1N=4 super-Yang-Mills at the conformal point is shown to contain strings: they are IIB strings. We conjecture that compactifications of M/string theory on various Anti-deSitter spacetimes is dual to various conformal field theories. This leads to a new proposal for a definition of M-theory which could be extended to include five non-compact dimensions. copyright 1999 American Institute of Physics
Energy Technology Data Exchange (ETDEWEB)
Sati, Hisham [University of Pittsburgh,Pittsburgh, PA, 15260 (United States); Mathematics Program, Division of Science and Mathematics, New York University Abu Dhabi,Saadiyat Island, Abu Dhabi (United Arab Emirates); Schreiber, Urs [Mathematics Institute of the Academy,Žitna 25, Praha 1, 115 67 (Czech Republic)
2017-03-16
We uncover higher algebraic structures on Noether currents and BPS charges. It is known that equivalence classes of conserved currents form a Lie algebra. We show that at least for target space symmetries of higher parameterized WZW-type sigma-models this naturally lifts to a Lie (p+1)-algebra structure on the Noether currents themselves. Applied to the Green-Schwarz-type action functionals for super p-brane sigma-models this yields super Lie (p+1)-algebra refinements of the traditional BPS brane charge extensions of supersymmetry algebras. We discuss this in the generality of higher differential geometry, where it applies also to branes with (higher) gauge fields on their worldvolume. Applied to the M5-brane sigma-model we recover and properly globalize the M-theory super Lie algebra extension of 11-dimensional superisometries by 2-brane and 5-brane charges. Passing beyond the infinitesimal Lie theory we find cohomological corrections to these charges in higher analogy to the familiar corrections for D-brane charges as they are lifted from ordinary cohomology to twisted K-theory. This supports the proposal that M-brane charges live in a twisted cohomology theory.
Negative branes, supergroups and the signature of spacetime
Dijkgraaf, Robbert; Heidenreich, Ben; Jefferson, Patrick; Vafa, Cumrun
2018-02-01
We study the realization of supergroup gauge theories using negative branes in string theory. We show that negative branes are intimately connected with the possibility of timelike compactification and exotic spacetime signatures previously studied by Hull. Isolated negative branes dynamically generate a change in spacetime signature near their worldvolumes, and are related by string dualities to a smooth M-theory geometry with closed timelike curves. Using negative D3-branes, we show that SU(0| N) supergroup theories are holographically dual to an exotic variant of type IIB string theory on {dS}_{3,2}× {\\overline{S}}^5 , for which the emergent dimensions are timelike. Using branes, mirror symmetry and Nekrasov's instanton calculus, all of which agree, we derive the Seiberg-Witten curve for N=2 SU( N | M ) gauge theories. Together with our exploration of holography and string dualities for negative branes, this suggests that supergroup gauge theories may be non-perturbatively well-defined objects, though several puzzles remain.
The quest of a unified theory of interactions
International Nuclear Information System (INIS)
Weingerg, St.; Hawking, St.; Mlodinow, L.; Lisi, G.; Weatherall, J.
2011-01-01
The unification of the 4 basic interactions is far from being achieved despite all the efforts made during decades. One theory states that unification is not possible unless to have the point of view of an observer outside the universe...This document is composed of 3 articles. In the first article, stakes, difficulties and the existing research axis of unification are presented. The second article is dedicated to the string theory that is the most promising according to scientists. In fact there are 5 string theories, each one explaining a limited range of phenomena. Nevertheless, string theories share common concepts called dualities, which made physicists think of a unique theory: the M theory that might lie behind the string theories. The third article presents a recent attempt of unification based on the E8 Lie group. Even if this E8 theory appears to be wrong, it will have shed light on deep geometrical relationships between particles that the real theory will have to explain. (A.C.)
Yang-Mills-Chern-Simons supergravity
International Nuclear Information System (INIS)
Lue, H; Pope, C N; Sezgin, E
2004-01-01
N = (1, 0) supergravity in six dimensions admits AdS 3 x S 3 as a vacuum solution. We extend our recent results presented in Lue et al (2002 Preprint hep-th/0212323), by obtaining the complete N = 4 Yang-Mills-Chern-Simons supergravity in D = 3, up to quartic fermion terms, by S 3 group manifold reduction of the six-dimensional theory. The SU(2) gauge fields have Yang-Mills kinetic terms as well as topological Chern-Simons mass terms. There is in addition a triplet of matter vectors. After diagonalization, these fields describe two triplets of topologically-massive vector fields of opposite helicities. The model also contains six scalars, described by a GL(3, R)/SO(3) sigma model. It provides the first example of a three-dimensional gauged supergravity that can be obtained by a consistent reduction of string theory or M-theory and that admits AdS 3 as a vacuum solution. There are unusual features in the reduction from six-dimensional supergravity, owing to the self-duality condition on the 3-form field. The structure of the full equations of motion in N = (1, 0) supergravity in D = 6 is also elucidated, and the role of the self-dual field strength as torsion is exhibited
Supergravity, Dark Energy and the Fate of the Universe
Energy Technology Data Exchange (ETDEWEB)
Shmakova, Marina
2002-09-27
We propose a description of dark energy and acceleration of the universe in extended supergravities with de Sitter (dS) solutions. Some of them are related to M-theory with non-compact internal spaces. Masses of ultra-light scalars in these models are quantized in units of the Hubble constant: m{sup 2} = nH{sup 2}. If dS solution corresponds to a minimum of the effective potential, the universe eventually becomes dS space. If dS solution corresponds to a maximum or a saddle point, which is the case in all known models based on N = 8 supergravity, the flat universe eventually stops accelerating and collapses to a singularity. We show that in these models, as well as in the simplest models of dark energy based on N = 1 supergravity, the typical time remaining before the global collapse is comparable to the present age of the universe, t = O(10{sup 10}) years. We discuss the possibility of distinguishing between various models and finding our destiny using cosmological observations.
Residues and world-sheet instantons
International Nuclear Information System (INIS)
Beasley, Chris; Witten, Edward
2003-01-01
We reconsider the question of which Calabi-Yau compactifications of the heterotic string are stable under world-sheet instanton corrections to the effective space-time superpotential. For instance, compactifications described by (0; 2) linear sigma models are believed to be stable, suggesting a remarkable cancellation among the instanton effects in these theories. Here, we show that this cancellation follows directly from a residue theorem, whose proof relies only upon the right-moving world-sheet supersymmetries and suitable compactness properties of the (0; 2) linear sigma model. Our residue theorem also extends to a new class of 'half-linear' sigma models. Using these half-linear models, we show that heterotic compactifications on the quintic hypersurface in CP 4 for which the gauge bundle pulls back from a bundle on CP 4 are stable. Finally, we apply similar ideas to compute the superpotential contributions from families of membrane instantons in M-theory compactifications on manifolds of G 2 holonomy. (author)
Discrete structures in F-theory compactifications
Energy Technology Data Exchange (ETDEWEB)
Till, Oskar
2016-05-04
In this thesis we study global properties of F-theory compactifications on elliptically and genus-one fibered Calabi-Yau varieties. This is motivated by phenomenological considerations as well as by the need for a deeper understanding of the set of consistent F-theory vacua. The global geometric features arise from discrete and arithmetic structures in the torus fiber and can be studied in detail for fibrations over generic bases. In the case of elliptic fibrations we study the role of the torsion subgroup of the Mordell-Weil group of sections in four dimensional compactifications. We show how the existence of a torsional section restricts the admissible matter representations in the theory. This is shown to be equivalent to inducing a non-trivial fundamental group of the gauge group. Compactifying F-theory on genus-one fibrations with multisections gives rise to discrete selection rules. In field theory the discrete symmetry is a broken U(1) symmetry. In the geometry the higgsing corresponds to a conifold transition. We explain in detail the origin of the discrete symmetry from two different M-theory phases and put the result into the context of torsion homology. Finally we systematically construct consistent gauge fluxes on genus-one fibrations and show that these induce an anomaly free chiral spectrum.
Non-renormalisation conditions in type II string theory and maximal supergravity
International Nuclear Information System (INIS)
Green, Michael B.; Russo, Jorge G.; Vanhove, Pierre
2007-01-01
This paper considers general features of the derivative expansion of Feynman diagram contributions to the four-graviton scattering amplitude in eleven-dimensional supergravity compactified on a two-torus. These are translated into statements about interactions of the form D 2k R 4 in type II superstring theories, assuming the standard M-theory/string theory duality relationships, which provide powerful constraints on the effective interactions. In the ten-dimensional IIA limit we find that there can be no perturbative contributions beyond k string loops (for k>0). Furthermore, the genus h = k contributions are determined exactly by the one-loop eleven-dimensional supergravity amplitude for all values of k. A plausible interpretation of these observations is that the sum of h-loop Feynman diagrams of maximally extended supergravity is less divergent than might be expected and could be ultraviolet finite in dimensions d<4+6/h - the same bound as for N = 4 Yang-Mills
Non-renormalisation conditions in type II string theory and maximal supergravity
Green, Michael B.; Russo, Jorge G.; Vanhove, Pierre
2007-02-01
This paper considers general features of the derivative expansion of Feynman diagram contributions to the four-graviton scattering amplitude in eleven-dimensional supergravity compactified on a two-torus. These are translated into statements about interactions of the form D2kR4 in type II superstring theories, assuming the standard M-theory/string theory duality relationships, which provide powerful constraints on the effective interactions. In the ten-dimensional IIA limit we find that there can be no perturbative contributions beyond k string loops (for k>0). Furthermore, the genus h = k contributions are determined exactly by the one-loop eleven-dimensional supergravity amplitude for all values of k. A plausible interpretation of these observations is that the sum of h-loop Feynman diagrams of maximally extended supergravity is less divergent than might be expected and could be ultraviolet finite in dimensions d<4+6/h - the same bound as for N = 4 Yang-Mills.
International Nuclear Information System (INIS)
Gabadadze, Gregory; Shifman, Mikhail
2000-01-01
A number of arguments exists that the ''minimal'' Bogomol'nyi-Prasad-Sommerfeld (BPS) wall width in large-N supersymmetric gluodynamics vanishes as 1/N. There is a certain tension between this assertion and the fact that the mesons coupled to λλ have masses O(N 0 ). To reconcile these facts we argue that there should exist additional solitonlike states with masses scaling as N. The BPS walls must be ''made'' predominantly of these heavy states which are coupled to λλ stronger than the conventional mesons. The tension of the BPS wall junction scales as N 2 , which serves as an additional argument in favor of the 1/N scaling of the wall width. The heavy states can be thought of as solitons of the corresponding closed string theory. They are related to certain fivebranes in the M-theory construction. We study the issue of the wall width in toy models which capture some features of supersymmetric gluodynamics. We speculate that the special hadrons with mass scaling as N should also exist in the large-N limit of nonsupersymmetric gluodynamics. (c) 2000 The American Physical Society
Energy Technology Data Exchange (ETDEWEB)
Gherson, D
2007-10-15
This work can be related to the Horava-Witten M-theory in which the Universe could appear 5 dimensional at a stage of its evolution but also to theories of Baryogenesis through Lepto-genesis which imply high reheating temperatures after Inflation. The studied cosmological model is within the framework of a 5 dimensional supergravity with the extra-dimension compactified on an orbifold circle, where the matter and gauge field are located on one of the two branes localised at the orbifold fixed points and where the supergravity fields can propagate in the whole spatial dimensions. In the model, the Dark matter is made of neutralino which is supposed to be the lightest supersymmetric particle. We have shown that there are curves of constraints between the size of the extra-dimension and the reheating temperature of the Universe after Inflation. The constraints come from the measurements of the amount of Dark matter in the Universe and from the model of the Big Bang Nucleosynthesis of light elements. (author)
N = 6 superconformal Chern-Simons-matter theories, M2-branes and their gravity duals
International Nuclear Information System (INIS)
Aharony, Ofer; Bergman, Oren; Maldacena, Juan; Jafferis, Daniel Louis
2008-01-01
We construct three dimensional Chern-Simons-matter theories with gauge groups U(N) x U(N) and SU(N) x SU(N) which have explicit N = 6 superconformal symmetry. Using brane constructions we argue that the U(N) x U(N) theory at level k describes the low energy limit of N M2-branes probing a C 4 /Z k singularity. At large N the theory is then dual to M-theory on AdS 4 x S 7 /Z k . The theory also has a 't Hooft limit (of large N with a fixed ratio N/k) which is dual to type IIA string theory on AdS 4 x CP 3 . For k = 1 the theory is conjectured to describe N M2-branes in flat space, although our construction realizes explicitly only six of the eight supersymmetries. We give some evidence for this conjecture, which is similar to the evidence for mirror symmetry in d = 3 gauge theories. When the gauge group is SU(2) x SU(2) our theory has extra symmetries and becomes identical to the Bagger-Lambert theory.
On thermodynamics of charged AdS black holes in extended phases space via M2-branes background
International Nuclear Information System (INIS)
Chabab, M.; Masmar, K.; El Moumni, H.
2016-01-01
Motivated by a recent work on asymptotically AdS 4 black holes in M-theory, we investigate both thermodynamics and the thermodynamical geometry of Reissner-Nordstrom-AdS black holes from M2-branes. More precisely, we study AdS black holes in AdS 4 x S 7 , with the number of M2-branes interpreted as a thermodynamical variable. In this context, we calculate various thermodynamical quantities including the chemical potential, and examine their phase transitions along with the corresponding stability behaviors. In addition, we also evaluate the thermodynamical curvatures of the Weinhold, Ruppeiner, and Quevedo metrics for M2-branes geometry to study the stability of such a black object. We show that the singularities of these scalar curvature's metrics reproduce similar stability results to those obtained by the phase transition diagram via the heat capacities in different ensembles either when the number of the M2 branes or the charge is held fixed. Also, we note that all results derived in Belhaj et al. (Eur Phys J C 76(2):73, 2016) are recovered in the limit of the vanishing charge. (orig.)
Brane brick models in the mirror
Energy Technology Data Exchange (ETDEWEB)
Franco, Sebastián [Physics Department, The City College of the CUNY,160 Convent Avenue, New York, NY 10031 (United States); The Graduate School and University Center, The City University of New York,365 Fifth Avenue, New York NY 10016 (United States); Lee, Sangmin [Center for Theoretical Physics, Seoul National University,Seoul 08826 (Korea, Republic of); Department of Physics and Astronomy, Seoul National University,Seoul 08826 (Korea, Republic of); College of Liberal Studies, Seoul National University,Seoul 08826 (Korea, Republic of); Seong, Rak-Kyeong [School of Physics, Korea Institute for Advanced Study,Seoul 02455 (Korea, Republic of); Vafa, Cumrun [Jefferson Physical Laboratory, Harvard University,Cambridge, MA 02138 (United States)
2017-02-21
Brane brick models are Type IIA brane configurations that encode the 2dN=(0,2) gauge theories on the worldvolume of D1-branes probing toric Calabi-Yau 4-folds. We use mirror symmetry to improve our understanding of this correspondence and to provide a systematic approach for constructing brane brick models starting from geometry. The mirror configuration consists of D5-branes wrapping 4-spheres and the gauge theory is determined by how they intersect. We also explain how 2d(0,2) triality is realized in terms of geometric transitions in the mirror geometry. Mirror symmetry leads to a geometric unification of dualities in different dimensions, where the order of duality is n−1 for a Calabi-Yau n-fold. This makes us conjecture the existence of a quadrality symmetry in 0d. Finally, we comment on how the M-theory lift of brane brick models connects to the classification of 2d(0,2) theories in terms of 4-manifolds.
Ekpyrotic and cyclic cosmology
International Nuclear Information System (INIS)
Lehners, Jean-Luc
2008-01-01
Ekpyrotic and cyclic cosmologies provide theories of the very early and of the very late universe. In these models, the big bang is described as a collision of branes - and thus the big bang is not the beginning of time. Before the big bang, there is an ekpyrotic phase with equation of state w=P/(ρ) >>1 (where P is the average pressure and ρ the average energy density) during which the universe slowly contracts. This phase resolves the standard cosmological puzzles and generates a nearly scale-invariant spectrum of cosmological perturbations containing a significant non-Gaussian component. At the same time it produces small-amplitude gravitational waves with a blue spectrum. The dark energy dominating the present-day cosmological evolution is reinterpreted as a small attractive force between our brane and a parallel one. This force eventually induces a new ekpyrotic phase and a new brane collision, leading to the idea of a cyclic universe. This review discusses the detailed properties of these models, their embedding in M-theory and their viability, with an emphasis on open issues and observational signatures
Equivariant Verlinde Algebra from Superconformal Index and Argyres-Seiberg Duality
Gukov, Sergei; Pei, Du; Yan, Wenbin; Ye, Ke
2018-02-01
In this paper, we show the equivalence between two seemingly distinct 2d TQFTs: one comes from the "Coulomb branch index" of the class S theory {T[Σ,G]} on {L(k,1) × S^1}, the other is the {^L G} "equivariant Verlinde formula", or equivalently partition function of {^L G_C} complex Chern-Simons theory on {Σ× S^1}. We first derive this equivalence using the M-theory geometry and show that the gauge groups appearing on the two sides are naturally G and its Langlands dual {^L G}. When G is not simply-connected, we provide a recipe of computing the index of {T[Σ,G]} as summation over the indices of T[Σ,\\tilde{G}] with non-trivial background 't Hooft fluxes, where \\tilde{G} is the universal cover of G. Then we check explicitly this relation between the Coulomb index and the equivariant Verlinde formula for {G=SU(2)} or SO(3). In the end, as an application of this newly found relation, we consider the more general case where G is SU( N) or PSU( N) and show that equivariant Verlinde algebra can be derived using field theory via (generalized) Argyres-Seiberg duality. We also attach a Mathematica notebook that can be used to compute the SU(3) equivariant Verlinde coefficients.
Toward a proof of Montonen-Olive duality via multiple M2-branes
International Nuclear Information System (INIS)
Hashimoto, Koji; Tai, Ta-Sheng; Terashima, Seiji
2009-01-01
We derive 4-dimensional N = 4 U(N) supersymmetric Yang-Mills theory from a 3-dimensional Chern-Simons-matter theory with product gauge group (U(N)) 2n . The latter describes M2-branes probing an orbifold where a torus emerges in a scaling limit. It is expected that the SL(2,Z) duality of the 4-dimensional Yang-Mills theory will be shown in M-theory point of view since it is trivially realized as modular transformations of the torus. Indeed, starting from one single Chern-Simons-matter theory, we find infinitely many equivalent 4-dimensional theories differing up to T-transformation of the SL(2,Z) redefinition of the gauge coupling τ = θ/2π + 4πi/g 2 and a parity transformation in 4 dimensions. Although S-transformation can not be shown in our work, it is important that a part of the SL(2,Z) transformation is realized via the M2-brane action. Thus we think our work can be a step toward a proof of Montonen-Olive duality via M2-branes.
Toward a proof of Montonen-Olive duality via multiple M2-branes
Hashimoto, Koji; Tai, Ta-Sheng; Terashima, Seiji
2009-04-01
We derive 4-dimensional Script N = 4 U(N) supersymmetric Yang-Mills theory from a 3-dimensional Chern-Simons-matter theory with product gauge group (U(N))2n. The latter describes M2-branes probing an orbifold where a torus emerges in a scaling limit. It is expected that the SL(2,Z) duality of the 4-dimensional Yang-Mills theory will be shown in M-theory point of view since it is trivially realized as modular transformations of the torus. Indeed, starting from one single Chern-Simons-matter theory, we find infinitely many equivalent 4-dimensional theories differing up to T-transformation of the SL(2,Z) redefinition of the gauge coupling τ = θ/2π + 4πi/g2 and a parity transformation in 4 dimensions. Although S-transformation can not be shown in our work, it is important that a part of the SL(2,Z) transformation is realized via the M2-brane action. Thus we think our work can be a step toward a proof of Montonen-Olive duality via M2-branes.
On Newton's law in supersymmetric braneworld models
Energy Technology Data Exchange (ETDEWEB)
Palma, G.A.
2007-05-15
We study the propagation of gravitons within 5-D supersymmetric braneworld models with a bulk scalar field. The setup considered here consists of a 5-D bulk spacetime bounded by two 4-D branes localized at the fixed points of an S{sup 1}/Z{sub 2} orbifold. There is a scalar field {phi} in the bulk which, provided a superpotential W({phi}), determines the warped geometry of the 5-D spacetime. This type of scenario is common in string theory, where the bulk scalar field {phi} is related to the volume of small compact extra dimensions. We show that, after the moduli are stabilized by supersymmetry breaking terms localized on the branes, the only relevant degrees of freedom in the bulk consist of a 5-D massive spectrum of gravitons. Then we analyze the gravitational interaction between massive bodies localized at the positive tension brane mediated by these bulk gravitons. It is shown that the Newtonian potential describing this interaction picks up a non-trivial contribution at short distances that depends on the shape of the superpotential W({phi}). We compute this contribution for dilatonic braneworld scenarios W({phi})=e{sup {alpha}}{sup {phi}} (where {alpha} is a constant) and discuss the particular case of 5-D Heterotic M-theory: It is argued that a specific footprint at micron scales could be observable in the near future. (orig.)
Thermodynamics of spinning branes and their dual field theories
DEFF Research Database (Denmark)
Harmark, Troels; Obers, N. A.
2000-01-01
We discuss general spinning p-branes of string and M-theory and use their thermodynamics along with the correspondence between near-horizon brane solutions and field theories with 16 supercharges to describe the thermodynamic behavior of these theories in the presence of voltages under the R......-symmetry. The thermodynamics is used to provide two pieces of evidence in favor of a smooth interpolation function between the free energy at weak and strong coupling of the field theory. (i) A computation of the boundaries of stability shows that for the D2, D3, D4, M2 and M5-branes the critical values of Omega/T in the two...... limits are remarkably close and (ii) The tree-level R^4 corrections to the spinning D3-brane generate a decrease in the free energy at strong coupling towards the weak coupling result. We also comment on the generalization to spinning brane bound states and their thermodynamics, which are relevant...
Non-commutative algebra of functions of 4-dimensional quantum Hall droplet
International Nuclear Information System (INIS)
Chen Yixin; Hou Boyu; Hou Boyuan
2002-01-01
We develop the description of non-commutative geometry of the 4-dimensional quantum Hall fluid's theory proposed recently by Zhang and Hu. The non-commutative structure of fuzzy S 4 , which is the base of the bundle S 7 obtained by the second Hopf fibration, i.e., S 7 /S 3 =S 4 , appears naturally in this theory. The fuzzy monopole harmonics, which are the essential elements in the non-commutative algebra of functions on S 4 , are explicitly constructed and their obeying the matrix algebra is obtained. This matrix algebra is associative. We also propose a fusion scheme of the fuzzy monopole harmonics of the coupling system from those of the subsystems, and determine the fusion rule in such fusion scheme. By products, we provide some essential ingredients of the theory of SO(5) angular momentum. In particular, the explicit expression of the coupling coefficients, in the theory of SO(5) angular momentum, are given. We also discuss some possible applications of our results to the 4-dimensional quantum Hall system and the matrix brane construction in M-theory
Accelerating universes driven by bulk particles
International Nuclear Information System (INIS)
Brito, F.A.; Cruz, F.F.; Oliveira, J.F.N.
2005-01-01
We consider our universe as a 3d domain wall embedded in a 5d dimensional Minkowski space-time. We address the problem of inflation and late time acceleration driven by bulk particles colliding with the 3d domain wall. The expansion of our universe is mainly related to these bulk particles. Since our universe tends to be permeated by a large number of isolated structures, as temperature diminishes with the expansion, we model our universe with a 3d domain wall with increasing internal structures. These structures could be unstable 2d domain walls evolving to fermi-balls which are candidates to cold dark matter. The momentum transfer of bulk particles colliding with the 3d domain wall is related to the reflection coefficient. We show a nontrivial dependence of the reflection coefficient with the number of internal dark matter structures inside the 3d domain wall. As the population of such structures increases the velocity of the domain wall expansion also increases. The expansion is exponential at early times and polynomial at late times. We connect this picture with string/M-theory by considering BPS 3d domain walls with structures which can appear through the bosonic sector of a five-dimensional supergravity theory
Impact of physical properties at very high energy scales on the superparticle mass spectrum
International Nuclear Information System (INIS)
Baer, H.; Diaz, M.; Quintana, P.; Tata, X.
2000-01-01
We survey a variety of proposals for new physics at high scales that serve to relate the multitude of soft supersymmetry breaking parameters of the MSSM. We focus on models where the new physics results in non-universal soft parameters, in sharp contrast with the usually assumed mSUGRA framework. These include (i) SU(5) and SO(10) grand unified (GUT) models, (ii) the MSSM plus a right-handed neutrino, (iii) models with effective supersymmetry, (iv) models with anomaly-mediated SUSY breaking and gaugino mediated SUSY breaking, (v) models with non-universal soft terms due to string dynamics, and (vi) models based on M-theory. We outline the physics behind these models, point out some distinctive features of the weak scale sparticle spectrum, and allude to implications for collider experiments. To facilitate future studies, for each of these scenarios, we describe how collider events can be generated using the program ISAJET. Our hope is that detailed studies of a variety of alternatives will help point to the physics underlying SUSY breaking and how this is mediated to the observable sector, once sparticles are discovered and their properties measured. (author)
String creation, D-branes and effective field theory
International Nuclear Information System (INIS)
Hung Lingyan
2008-01-01
This paper addresses several unsettled issues associated with string creation in systems of orthogonal Dp-D(8-p) branes. The interaction between the branes can be understood either from the closed string or open string picture. In the closed string picture it has been noted that the DBI action fails to capture an extra RR exchange between the branes. We demonstrate how this problem persists upon lifting to M-theory. These D-brane systems are analysed in the closed string picture by using gauge-fixed boundary states in a non-standard lightcone gauge, in which RR exchange can be analysed precisely. The missing piece in the DBI action also manifests itself in the open string picture as a mismatch between the Coleman-Weinberg potential obtained from the effective field theory and the corresponding open string calculation. We show that this difference can be reconciled by taking into account the superghosts in the (0+1) effective theory of the chiral fermion, that arises from gauge fixing the spontaneously broken world-line local supersymmetries
Unitary Supermultiplets of $OSp(8^{*}|4)$ and the $AdS_{7}/CFT_{6}$ Duality
Günaydin, M; Gunaydin, Murat; Takemae, Seiji
2000-01-01
We study the unitary supermultiplets of the N=4 d=7 anti-de Sitter (AdS_7) superalgebra OSp(8^*|4), with the even subalgebra SO(6,2) X USp(4), which is the symmetry superalgebra of M-theory on AdS_7 X S^4. We give a complete classification of the positive energy doubleton and massless supermultiplets of OSp(8^*|4) . The ultra-short doubleton supermultiplets do not have a Poincaré limit in AdS_7 and correspond to superconformal field theories on the boundary of AdS_7 which can be identified with d=6 Minkowski space. We show that the six dimensional Poincare mass operator vanishes identically for the doubleton representations. By going from the compact U(4) basis of SO^*(8)=SO(6,2) to the noncompact basis SU^*(4)XD (d=6 Lorentz group times dilatations) one can associate the positive (conformal) energy representations of SO^*(8) with conformal fields transforming covariantly under the Lorentz group in d=6. The oscillator method used for the construction of the unitary supermultiplets of OSp(8^*|4) can be given ...
Critical solutions of topologically gauged N=8 CFTs in three dimensions
Energy Technology Data Exchange (ETDEWEB)
Nilsson, Bengt E.W. [Fundamental Physics, Chalmers University of Technology,SE-412 96 Göteborg (Sweden)
2014-04-16
In this paper we discuss some special (critical) background solutions that arise in topological gauged N=8 three-dimensional CFTs with SO(N) gauge group. Depending on how many scalar fields are given a VEV the theory has background solutions for certain values of μl, where μ and l are parameters in the TMG Lagrangian. Apart from Minkowski, chiral round AdS{sub 3} and null-warped AdS{sub 3} (or Schrödinger(z=2)) we identify also a more exotic solution recently found in TMG by Ertl, Grumiller and Johansson. We also discuss the spectrum, symmetry breaking pattern and the supermultiplet structure in the various backgrounds and argue that some properties are due to their common origin in a conformal phase. Some of the scalar fields, including all higgsed ones, turn out to satisfy three-dimensional field equations similar to those of the singleton. Finally, we note that topologically gauged N=6 ABJ(M) theories have a similar, but more restricted, set of background solutions.
Critical solutions of topologically gauged N=8 CFTs in three dimensions
International Nuclear Information System (INIS)
Nilsson, Bengt E.W.
2014-01-01
In this paper we discuss some special (critical) background solutions that arise in topological gauged N=8 three-dimensional CFTs with SO(N) gauge group. Depending on how many scalar fields are given a VEV the theory has background solutions for certain values of μl, where μ and l are parameters in the TMG Lagrangian. Apart from Minkowski, chiral round AdS 3 and null-warped AdS 3 (or Schrödinger(z=2)) we identify also a more exotic solution recently found in TMG by Ertl, Grumiller and Johansson. We also discuss the spectrum, symmetry breaking pattern and the supermultiplet structure in the various backgrounds and argue that some properties are due to their common origin in a conformal phase. Some of the scalar fields, including all higgsed ones, turn out to satisfy three-dimensional field equations similar to those of the singleton. Finally, we note that topologically gauged N=6 ABJ(M) theories have a similar, but more restricted, set of background solutions
Three-form periods on Calabi-Yau fourfolds: toric hypersurfaces and F-theory applications
Energy Technology Data Exchange (ETDEWEB)
Greiner, Sebastian; Grimm, Thomas W. [Institute for Theoretical Physics and Center for Extreme Matter and Emergent Phenomena, Utrecht University,Leuvenlaan 4, 3584 CE Utrecht (Netherlands); Max-Planck-Institut für Physik, Föhringer Ring 6, 80805 Munich (Germany)
2017-05-30
The study of the geometry of Calabi-Yau fourfolds is relevant for compactifications of string theory, M-theory, and F-theory to various dimensions. This work introduces the mathematical machinery to derive the complete moduli dependence of the periods of non-trivial three-forms for fourfolds realized as hypersurfaces in toric ambient spaces. It sets the stage to determine Picard-Fuchs-type differential equations and integral expressions for these forms. The key tool is the observation that non-trivial three-forms on fourfold hypersurfaces in toric ambient spaces always stem from divisors that are build out of trees of toric surfaces fibered over Riemann surfaces. The three-form periods are then non-trivially related to the one-form periods of these Riemann surfaces. In general, the three-form periods are known to vary holomorphically over the complex structure moduli space and play an important role in the effective actions arising in fourfold compactifications. We discuss two explicit example fourfolds for F-theory compactifications in which the three-form periods determine axion decay constants.
Gravitino in the early Universe. A model of extra-dimension and a model of dark matter
International Nuclear Information System (INIS)
Gherson, D.
2007-10-01
This work can be related to the Horava-Witten M-theory in which the Universe could appear 5 dimensional at a stage of its evolution but also to theories of Baryogenesis through Lepto-genesis which imply high reheating temperatures after Inflation. The studied cosmological model is within the framework of a 5 dimensional supergravity with the extra-dimension compactified on an orbifold circle, where the matter and gauge field are located on one of the two branes localised at the orbifold fixed points and where the supergravity fields can propagate in the whole spatial dimensions. In the model, the Dark matter is made of neutralino which is supposed to be the lightest supersymmetric particle. We have shown that there are curves of constraints between the size of the extra-dimension and the reheating temperature of the Universe after Inflation. The constraints come from the measurements of the amount of Dark matter in the Universe and from the model of the Big Bang Nucleosynthesis of light elements. (author)
Unity from duality: gravity, gauge theory and strings
International Nuclear Information System (INIS)
Bachas, C.; Bilal, A.; Douglas, M.; Nekrasov, N.; David, F.
2002-01-01
The 76. session of the summer school in theoretical physics was devoted to recent developments in string theory, gauge theories and quantum gravity. Superstring theory is the leading candidate for a unified theory of all fundamental physical forces and elementary particles. The discovery of dualities and of important tools such as D-branes, has greatly reinforced this point of view. This document gathers the papers of 9 lectures: 1) supergravity, 2) supersymmetric gauge theories, 3) an introduction to duality symmetries, 4) large N field theories and gravity, 5) D-branes on the conifold and N = 1 gauge/gravity dualities, 6) de Sitter space, 7) string compactification with N = 1 supersymmetry, 8) open strings and non-commutative gauge theories, and 9) condensates near the Argyres-Douglas point in SU(2) gauge theory with broken N = 2 supersymmetry, and of 8 seminars: 1) quantum field theory with extra dimensions, 2) special holonomy spaces and M-theory, 3) four dimensional non-critical strings, 4) U-opportunities: why ten equal to ten?, 5) exact answers to approximate questions - non-commutative dipoles, open Wilson lines and UV-IR duality, 6) open-string models with broken supersymmetry, 7) on a field theory of open strings, tachyon condensation and closed strings, and 8) exceptional magic. (A.C.)
Open string T-duality in double space
International Nuclear Information System (INIS)
Sazdovic, B.
2017-01-01
The role of double space is essential in the new interpretation of T-duality and consequently in an attempt to construct M-theory. The case of the open string is missing in such an approach because until now there has been no appropriate formulation of open string T-duality. In the previous paper (Sazdovic, From geometry to non-geometry via T-duality, arXiv:1606.01938, 2017), we showed how to introduce vector gauge fields A"N_a and A"D_i at the end-points of an open string in order to enable open string invariance under local gauge transformations of the Kalb-Ramond field and its T-dual ''restricted general coordinate transformations''. We demonstrated that gauge fields A"N_a and A"D_i are T-dual to each other. In the present article we prove that all above results can be interpreted as coordinate permutations in double space. (orig.)
Internal circle uplifts, transversality and stratified G-structures
Energy Technology Data Exchange (ETDEWEB)
Babalic, Elena Mirela [Department of Theoretical Physics, National Institute of Physics and Nuclear Engineering,Str. Reactorului no.30, P.O.BOX MG-6, Postcode 077125, Bucharest-Magurele (Romania); Department of Physics, University of Craiova,13 Al. I. Cuza Str., Craiova 200585 (Romania); Lazaroiu, Calin Iuliu [Center for Geometry and Physics, Institute for Basic Science,Pohang 790-784 (Korea, Republic of)
2015-11-24
We study stratified G-structures in N=2 compactifications of M-theory on eight-manifolds M using the uplift to the auxiliary nine-manifold M̂=M×S{sup 1}. We show that the cosmooth generalized distribution D̂ on M̂ which arises in this formalism may have pointwise transverse or non-transverse intersection with the pull-back of the tangent bundle of M, a fact which is responsible for the subtle relation between the spinor stabilizers arising on M and M̂ and for the complicated stratified G-structure on M which we uncovered in previous work. We give a direct explanation of the latter in terms of the former and relate explicitly the defining forms of the SU(2) structure which exists on the generic locus U of M to the defining forms of the SU(3) structure which exists on an open subset Û of M̂, thus providing a dictionary between the eight- and nine-dimensional formalisms.
Controlling chaos through compactification in cosmological models with a collapsing phase
International Nuclear Information System (INIS)
Wesley, Daniel H.; Steinhardt, Paul J.; Turok, Neil
2005-01-01
We consider the effect of compactification of extra dimensions on the onset of classical chaotic mixmaster behavior during cosmic contraction. Assuming a universe that is well-approximated as a four-dimensional Friedmann-Robertson-Walker model (with negligible Kaluza-Klein excitations) when the contraction phase begins, we identify compactifications that allow a smooth contraction and delay the onset of chaos until arbitrarily close to the big crunch. These compactifications are defined by the de Rham cohomology (Betti numbers) and Killing vectors of the compactification manifold. We find compactifications that control chaos in vacuum Einstein gravity, as well as in string theories with N=1 supersymmetry and M-theory. In models where chaos is controlled in this way, the universe can remain homogeneous and flat until it enters the quantum gravity regime. At this point, the classical equations leading to chaotic behavior can no longer be trusted, and quantum effects may allow a smooth approach to the big crunch and transition into a subsequent expanding phase. Our results may be useful for constructing cosmological models with contracting phases, such as the ekpyrotic/cyclic and pre-big bang models
Eringen, A C
1990-01-01
This is the second volume of a two-volume set presenting a unified approach to the electrodynamics of continua, based on the principles of contemporary continuum of physics. The first volume was devoted mainly to the development of the theory and applications to deformable solid media. This volume extends the developments of the first volume to richer and newer grounds. It contains discussions on fluid media, magnetohydrodynamics, eletrohydrodynamics and media with more complicated structures. With the discussion, in the last two chapters, of memory-dependent materials and non-local E-M theory, the authors account for the nonlocal effects arising from motions and fields of material points at past times and at spatially distant points. This discussion is included here to stimulate further research in these important fields, which are presently in development stages. The second volume is self-contained and can be studied without the help of volume I. A section summarizing the constitutive equations and the unde...
Supergravitational conformal Galileons
Deen, Rehan; Ovrut, Burt
2017-08-01
The worldvolume actions of 3+1 dimensional bosonic branes embedded in a five-dimensional bulk space can lead to important effective field theories, such as the DBI conformal Galileons, and may, when the Null Energy Condition is violated, play an essential role in cosmological theories of the early universe. These include Galileon Genesis and "bouncing" cosmology, where a pre-Big Bang contracting phase bounces smoothly to the presently observed expanding universe. Perhaps the most natural arena for such branes to arise is within the context of superstring and M -theory vacua. Here, not only are branes required for the consistency of the theory, but, in many cases, the exact spectrum of particle physics occurs at low energy. However, such theories have the additional constraint that they must be N = 1 supersymmetric. This motivates us to compute the worldvolume actions of N = 1 supersymmetric three-branes, first in flat superspace and then to generalize them to N = 1 supergravitation. In this paper, for simplicity, we begin the process, not within the context of a superstring vacuum but, rather, for the conformal Galileons arising on a co-dimension one brane embedded in a maximally symmetric AdS 5 bulk space. We proceed to N = 1 supersymmetrize the associated worldvolume theory and then generalize the results to N = 1 supergravity, opening the door to possible new cosmological scenarios
Cosmology from quantum potential in brane–anti-brane system
Directory of Open Access Journals (Sweden)
Alireza Sepehri
2015-09-01
Full Text Available Recently, some authors removed the big-bang singularity and predicted an infinite age of our universe. In this paper, we show that the same result can be obtained in string theory and M-theory; however, the shape of universe changes in different epochs. In our mechanism, first, N fundamental string decay to N D0–anti-D0-brane. Then, D0-branes join each other, grow and form a six-dimensional brane–antibrane system. This system is unstable, broken and at present the form of four-dimensional universes, one anti-universe in addition to one wormhole are produced. Thus, there isn't any big-bang in cosmology and the universe is a fundamental string at the beginning. Also, the total age of universe contains two parts, one is related to initial age and the other corresponds to the present age of universe (ttot=tinitial+tpresent. On the other hand, the initial age of universe includes two parts, the age of fundamental string and the time of transition (tinitial=ttransition+tf-string. We observe that only in the case of (tf-string→∞, the scale factor of universe is zero and as a result, the total age of universe is infinity.
On the equivalence of N=1 brane worlds and geometric singularities with flux
International Nuclear Information System (INIS)
Kaste, Peter; Partouche, Herve
2004-01-01
We consider Kaluza Klein reductions of M-theory on the Z N orbifold of the spin bundle over S 3 along two different U(1) isometries. The first one gives rise to the familiar 'large-N duality' of the N=1 SU(N) gauge theory in which the UV is realized as the world-volume theory of N D6-branes wrapped on S 3 , whereas the IR involves N units of RR flux through an S 2 . The second reduction gives an equivalent version of this duality in which the UV is realized geometrically in terms of a P 1 of A N-1 singularities, with one unit of RR flux through the P 1 . The IR is reached via a geometric transition and involves a single D6 brane on a lens space S 3 /Z N or, alternatively, a singular background (S 2 xR 4 )/Z N , with one unit of RR flux through S 2 and, localized at the singularities, an action of their stabilizer group in the U(1) RR gauge bundle, so that no massless twisted states occur. We also consider linear s-model descriptions of these backgrounds. (author)
Models and structures: mathematical physics
International Nuclear Information System (INIS)
2003-01-01
This document gathers research activities along 5 main directions. 1) Quantum chaos and dynamical systems. Recent results concern the extension of the exact WKB method that has led to a host of new results on the spectrum and wave functions. Progress have also been made in the description of the wave functions of chaotic quantum systems. Renormalization has been applied to the analysis of dynamical systems. 2) Combinatorial statistical physics. We see the emergence of new techniques applied to various such combinatorial problems, from random walks to random lattices. 3) Integrability: from structures to applications. Techniques of conformal field theory and integrable model systems have been developed. Progress is still made in particular for open systems with boundary conditions, in connection to strings and branes physics. Noticeable links between integrability and exact WKB quantization to 2-dimensional disordered systems have been highlighted. New correlations of eigenvalues and better connections to integrability have been formulated for random matrices. 4) Gravities and string theories. We have developed aspects of 2-dimensional string theory with a particular emphasis on its connection to matrix models as well as non-perturbative properties of M-theory. We have also followed an alternative path known as loop quantum gravity. 5) Quantum field theory. The results obtained lately concern its foundations, in flat or curved spaces, but also applications to second-order phase transitions in statistical systems
Primordial spectra of slow-roll inflation at second-order with the Gauss-Bonnet correction
Wu, Qiang; Zhu, Tao; Wang, Anzhong
2018-05-01
The slow-roll inflation for a single scalar field that couples to the Gauss-Bonnet (GB) term represents an important higher-order curvature correction inspired by string theory. With the arrival of the era of precision cosmology, it is expected that the high-order corrections become more and more important. In this paper we study the observational predictions of the slow-roll inflation with the GB term by using the third-order uniform asymptotic approximation method. We calculate explicitly the primordial power spectra, spectral indices, running of the spectral indices for both scalar and tensor perturbations, and the ratio between tensor and scalar spectra. These expressions are all written in terms of the Hubble and GB coupling flow parameters and expanded up to the next-to-leading order in the slow-roll expansions so they represent the most accurate results obtained so far in the literature. In addition, by studying the theoretical predictions of the scalar spectral index and the tensor-to-scalar ratio with the Planck 2015 constraints in a model with power-law potential and GB coupling, we show that the second-order corrections are important in the future measurements. We expect that the understanding of the GB corrections in the primordial spectra and their constraints by forthcoming observational data will provide clues for the UV complete theory of quantum gravity, such as the string/M-theory.
Weird universe exploring the most bizarre ideas in cosmology
Seargent, David A J
2015-01-01
As new discoveries complicate the scientific picture of the universe, the evolving theories about the nature of space and time and the origins and fate of the universe threaten to become overwhelming. Enter David Seargent. Continuing the author's series of books popularizing strange astronomy facts and knowledge, Weird Universe explains the bizarre, complicated terrain of modern cosmology for lay readers. From exploring some of the strange consequences of the theories of special and general relativity, to probing time dilation and the twin and mother-and-baby “paradoxes” and the theory that the universe can be mathematically considered as a hologram, all of the latest findings and conjectures are clearly described in non-technical language. The development of quantum physics and the more recent developments of string and M-theory are looked at, in addition to several hypotheses that have not won wide acceptance from the scientific community, such as modified gravity. Enter the wonderfully weird worl...
Color matching of fabric blends: hybrid Kubelka-Munk + artificial neural network based method
Furferi, Rocco; Governi, Lapo; Volpe, Yary
2016-11-01
Color matching of fabric blends is a key issue for the textile industry, mainly due to the rising need to create high-quality products for the fashion market. The process of mixing together differently colored fibers to match a desired color is usually performed by using some historical recipes, skillfully managed by company colorists. More often than desired, the first attempt in creating a blend is not satisfactory, thus requiring the experts to spend efforts in changing the recipe with a trial-and-error process. To confront this issue, a number of computer-based methods have been proposed in the last decades, roughly classified into theoretical and artificial neural network (ANN)-based approaches. Inspired by the above literature, the present paper provides a method for accurate estimation of spectrophotometric response of a textile blend composed of differently colored fibers made of different materials. In particular, the performance of the Kubelka-Munk (K-M) theory is enhanced by introducing an artificial intelligence approach to determine a more consistent value of the nonlinear function relationship between the blend and its components. Therefore, a hybrid K-M+ANN-based method capable of modeling the color mixing mechanism is devised to predict the reflectance values of a blend.
Eisenstein series and string thresholds
International Nuclear Information System (INIS)
Obers, N.A.; Pioline, B.
2000-01-01
We investigate the relevance of Eisenstein series for representing certain G(Z)-invariant string theory amplitudes which receive corrections from BPS states only. G(Z) may stand for any of the mapping class, T-duality and U-duality groups Sl(d,Z), SO(d,d,Z) or E d+1(d+1) (Z) respectively. Using G(Z)-invariant mass formulae, we construct invariant modular functions on the symmetric space K backslash G(R) of non-compact type, with K the maximal compact subgroup of G(R), that generalize the standard non-holomorphic Eisenstein series arising in harmonic analysis on the fundamental domain of the Poincare upper half-plane. Comparing the asymptotics and eigenvalues of the Eisenstein series under second order differential operators with quantities arising in one- and g-loop string amplitudes, we obtain a manifestly T-duality invariant representation of the latter, conjecture their non-perturbative U-duality invariant extension, and analyze the resulting non-perturbative effects. This includes the R 4 and R 4 H -4 g -4 couplings in toroidal compactifications of M-theory to any dimension D≥4 and D≥6 respectively. (orig.)
Asakura, Nobuhiko; Inui, Toshio
2016-01-01
Two apparently contrasting theories have been proposed to account for the development of children's theory of mind (ToM): theory-theory and simulation theory. We present a Bayesian framework that rationally integrates both theories for false belief reasoning. This framework exploits two internal models for predicting the belief states of others: one of self and one of others. These internal models are responsible for simulation-based and theory-based reasoning, respectively. The framework further takes into account empirical studies of a developmental ToM scale (e.g., Wellman and Liu, 2004): developmental progressions of various mental state understandings leading up to false belief understanding. By representing the internal models and their interactions as a causal Bayesian network, we formalize the model of children's false belief reasoning as probabilistic computations on the Bayesian network. This model probabilistically weighs and combines the two internal models and predicts children's false belief ability as a multiplicative effect of their early-developed abilities to understand the mental concepts of diverse beliefs and knowledge access. Specifically, the model predicts that children's proportion of correct responses on a false belief task can be closely approximated as the product of their proportions correct on the diverse belief and knowledge access tasks. To validate this prediction, we illustrate that our model provides good fits to a variety of ToM scale data for preschool children. We discuss the implications and extensions of our model for a deeper understanding of developmental progressions of children's ToM abilities.
String dynamics at strong coupling
International Nuclear Information System (INIS)
Hull, C.M.
1996-01-01
The dynamics of superstring, supergravity and M-theories and their compactifications are probed by studying the various perturbation theories that emerge in the strong and weak-coupling limits for various directions in coupling constant space. The results support the picture of an underlying non-perturbative theory that, when expanded perturbatively in different coupling constants, gives different perturbation theories, which can be perturbative superstring theories or superparticle theories. The p-brane spectrum is considered in detail and a criterion found to establish which p-branes govern the strong-coupling dynamics. In many cases there are competing conjectures in the literature, and this analysis decides between them. In other cases, new results are found. The chiral 6-dimensional theory resulting from compactifying the type IIB string on K 3 is studied in detail and it is found that certain strong-coupling limits appear to give new theories, some of which hint at the possibility of a 12-dimensional origin. (orig.)
Aspects of defects in 3d-3d correspondence
International Nuclear Information System (INIS)
Gang, Dongmin; Kim, Nakwoo; Romo, Mauricio; Yamazaki, Masahito
2016-01-01
In this paper we study supersymmetric co-dimension 2 and 4 defects in the compactification of the 6d (2,0) theory of type A_N_−_1 on a 3-manifold M. The so-called 3d-3d correspondence is a relation between complexified Chern-Simons theory (with gauge group SL(N,ℂ)) on M and a 3d N=2 theory T_N[M]. We study this correspondence in the presence of supersymmetric defects, which are knots/links inside the 3-manifold. Our study employs a number of different methods: state-integral models for complex Chern-Simons theory, cluster algebra techniques, domain wall theory T[SU(N)], 5d N=2 SYM, and also supergravity analysis through holography. These methods are complementary and we find agreement between them. In some cases the results lead to highly non-trivial predictions on the partition function. Our discussion includes a general expression for the cluster partition function, which can be used to compute in the presence of maximal and certain class of non-maximal punctures when N>2. We also highlight the non-Abelian description of the 3d N=2T_N[M] theory with defect included, when such a description is available. This paper is a companion to our shorter paper http://dx.doi.org/10.1088/1751-8113/49/30/30LT02, which summarizes our main results.
Superconformal Chern-Simons theories and AdS4/CFT3 correspondence
International Nuclear Information System (INIS)
Benna, Marcus; Klebanov, Igor; Klose, Thomas; Smedbaeck, Mikael
2008-01-01
We discuss the N = 2 superspace formulation of the N = 8 superconformal Bagger-Lambert-Gustavsson theory, and of the N = 6 superconformal Aharony-Bergman-Jafferis-Maldacena U(N) x U(N) Chern-Simons theory. In particular, we prove the full SU(4) R-symmetry of the ABJM theory. We then consider orbifold projections of this theory that give non-chiral and chiral (U(N) x U(N)) n superconformal quiver gauge theories. We argue that these theories are dual to certain AdS 4 x S 7 /(Z n x Z k -tilde) backgrounds of M-theory. We also study a SU(3) invariant mass term in the superpotential that makes the N = 8 theory flow to a N = 2 superconformal gauge theory with a sextic superpotential. We conjecture that this gauge theory is dual to the U(1) R x SU(3) invariant extremum of the N = 8 gauged supergravity, which was discovered by N. Warner 25 years ago and whose uplifting to 11 dimensions was found more recently.
Anomaly on Superspace of Time Series Data
Capozziello, Salvatore; Pincak, Richard; Kanjamapornkul, Kabin
2017-11-01
We apply the G-theory and anomaly of ghost and antighost fields in the theory of supersymmetry to study a superspace over time series data for the detection of hidden general supply and demand equilibrium in the financial market. We provide proof of the existence of a general equilibrium point over 14 extradimensions of the new G-theory compared with the M-theory of the 11 dimensions model of Edward Witten. We found that the process of coupling between nonequilibrium and equilibrium spinor fields of expectation ghost fields in the superspace of time series data induces an infinitely long exact sequence of cohomology from a short exact sequence of moduli state space model. If we assume that the financial market is separated into two topological spaces of supply and demand as the D-brane and anti-D-brane model, then we can use a cohomology group to compute the stability of the market as a stable point of the general equilibrium of the interaction between D-branes of the market. We obtain the result that the general equilibrium will exist if and only if the 14th Batalin-Vilkovisky cohomology group with the negative dimensions underlying 14 major hidden factors influencing the market is zero.
Staggered multi-field inflation
International Nuclear Information System (INIS)
Battefeld, Diana; Battefeld, Thorsten; Davis, Anne-Christine
2008-01-01
We investigate multi-field inflationary scenarios with fields that drop out of the model in a staggered fashion. This feature is natural in certain multi-field inflationary setups within string theory; for instance, it can manifest itself when fields are related to tachyons that condense, or inter-brane distances that become meaningless when branes annihilate. Considering a separable potential, and promoting the number of fields to a smooth time dependent function, we derive the formalism to deal with these models at the background and perturbed level, providing general expressions for the scalar spectral index and the running. We recover known results of e.g. a dynamically relaxing cosmological constant in the appropriate limits. We further show that isocurvature perturbations are suppressed during inflation, and so perturbations are adiabatic and nearly Gaussian. The resulting setup might be interpreted as a novel type of warm inflation, readily implemented within string theory and without many of the shortcomings associated with warm inflation. To exemplify the applicability of the formalism we consider three concrete models: assisted inflation with exponential potentials as a simple toy model (a graceful exit becomes possible), inflation from multiple tachyons (a constant decay rate of the number of fields and negligible slow roll contributions turns out to be in good agreement with observations) and inflation from multiple M5-branes within M-theory (a narrow stacking of branes yields a consistent scenario)
Geometric transitions, flops and non-Kahler manifolds: II
International Nuclear Information System (INIS)
Becker, Melanie; Dasgupta, Keshav; Katz, Sheldon; Knauf, Anke; Tatar, Radu
2006-01-01
We continue our study of geometric transitions in type II and heterotic theories. In type IIB theory we discuss an F-theory setup which clarifies many of our earlier assumptions and allows us to study gravity duals of N=1 gauge theories with arbitrary global symmetry group G. We also point out the subtle differences between global and local metrics, and show that in many cases the global descriptions are far more complicated than discussed earlier. We determine the full global description in type I/heterotic theory. In type IIA, our analysis gives rise to a local non-Kahler metric whose global description involves a particular orientifold action with gauge fluxes localised on branes. We are also able to identify the three form fields that allow for a smooth flop in the M-theory lift. We briefly discuss the issues of generalized complex structures in type IIB theory and possible half-twisted models in the heterotic duals of our type II models. In a companion paper we will present details on the topological aspects of these models
BIonic system: Extraction of Lovelock gravity from a Born-Infeld-type theory
Naimi, Yaghoob; Sepehri, Alireza; Ghaffary, Tooraj; Ghaforyan, Hossein; Ebrahimzadeh, Majid
It was shown that both Lovelock gravity and Born-Infeld (BI) electrodynamics can be obtained from low effective limit of string theory. Motivated by the mentioned unique origin of the gauge-gravity theories, we are going to find a close relation between them. In this research, we start from the Lagrangian of a BI-type nonlinear electrodynamics with an exponential form to extract the action of Lovelock gravity. We investigate the origin of Lovelock gravity in a system of branes which are connected with each other by different wormholes through a BIonic system. These wormholes are produced as due to the nonlinear electrodynamics which are emerged on the interacting branes. By approaching branes, wormholes dissolve into branes and Lovelock gravity is generated. Also, throats of some wormholes become smaller than their horizons and they transit to black holes. Generalizing calculations to M-theory, it is found that by compacting Mp-branes, Lovelock gravity changes to nonlinear electrodynamics and thus both of them have the same origin. This result is consistent with the prediction of BIonic model in string theory.
Holographic protection of chronology in universes of the Goedel type
International Nuclear Information System (INIS)
Boyda, Edward K.; Ganguli, Surya; Horava, Petr; Varadarajan, Uday
2003-01-01
We analyze the structure of supersymmetric Goedel-like cosmological solutions of string theory. Just as the original four-dimensional Goedel universe, these solutions represent rotating, topologically trivial cosmologies with a homogeneous metric and closed timelike curves. First we focus on the 'phenomenological' aspects of holography, and identify the preferred holographic screens associated with inertial comoving observers in Goedel universes. We find that holography can serve as a chronology protection agency: The closed timelike curves are either hidden behind the holographic screen, or broken by it into causal pieces. In fact, holography in Goedel universes has many features in common with de Sitter space, suggesting that Goedel universes could represent a supersymmetric laboratory for addressing the conceptual puzzles of de Sitter holography. Then we initiate the investigation of 'microscopic' aspects of holography of Goedel universes in string theory. We show that Goedel universes are T dual to pp waves, and use this fact to generate new Goedel-like solutions of string and M theory by T dualizing known supersymmetric pp-wave solutions
Energy Technology Data Exchange (ETDEWEB)
Sepehri, Alireza, E-mail: alireza.sepehri@uk.ac.ir [Faculty of Physics, Shahid Bahonar University, P.O. Box 76175, Kerman (Iran, Islamic Republic of); Research Institute for Astronomy and Astrophysics of Maragha (RIAAM), P.O. Box 55134-441, Maragha (Iran, Islamic Republic of)
2016-07-01
Recently, some authors (Cruz and Rojas, 2013 [1]) have constructed a Born–Infeld type action which may be written in terms of the Lovelock brane Lagrangians for a given dimension p. We reconsider their model in M-theory and study the process of birth and growth of nonlinear spinor and bosonic gravity during the construction of Mp-branes. Then, by application of this idea to BIonic system, we construct a BIonic superconductor in the background of nonlinear gravity. In this model, first, M0-branes link to each other and build an M5-brane and an anti-M5-brane connected by an M2-brane. M0-branes are zero dimensional objects that only scalars are attached to them. By constructing higher dimensional branes from M0-branes, gauge fields are produced. Also, if M0-branes don't link to each other completely, the symmetry of system is broken and fermions are created. The curvature produced by fermions has the opposite sign the curvature produced by gauge fields. Fermions on M5-branes and M2 plays the role of bridge between them. By passing time, M2 dissolves in M5's and nonlinear bosonic and spinor gravities are produced. By closing M5-branes towards each other, coupling of two identical fermions on two branes to each other causes that the square mass of their system becomes negative and some tachyonic states are created. For removing these tachyons, M5-branes compact, the sign of gravity between branes reverses, anti-gravity is produced which causes that branes and identical fermions get away from each other. This is the reason for the emergence of Pauli exclusion principle in Bionic system. Also, the spinor gravity vanishes and its energy builds a new M2 between M5-branes. We obtain the resistivity in this system and find that its value decreases by closing M5 branes to each other and shrinks to zero at colliding point of branes. This idea has different applications. For example, in cosmology, universes are located on M5-branes and M2-brane has the role of bridge
International Nuclear Information System (INIS)
Sepehri, Alireza
2016-01-01
Recently, some authors (Cruz and Rojas, 2013 [1]) have constructed a Born–Infeld type action which may be written in terms of the Lovelock brane Lagrangians for a given dimension p. We reconsider their model in M-theory and study the process of birth and growth of nonlinear spinor and bosonic gravity during the construction of Mp-branes. Then, by application of this idea to BIonic system, we construct a BIonic superconductor in the background of nonlinear gravity. In this model, first, M0-branes link to each other and build an M5-brane and an anti-M5-brane connected by an M2-brane. M0-branes are zero dimensional objects that only scalars are attached to them. By constructing higher dimensional branes from M0-branes, gauge fields are produced. Also, if M0-branes don't link to each other completely, the symmetry of system is broken and fermions are created. The curvature produced by fermions has the opposite sign the curvature produced by gauge fields. Fermions on M5-branes and M2 plays the role of bridge between them. By passing time, M2 dissolves in M5's and nonlinear bosonic and spinor gravities are produced. By closing M5-branes towards each other, coupling of two identical fermions on two branes to each other causes that the square mass of their system becomes negative and some tachyonic states are created. For removing these tachyons, M5-branes compact, the sign of gravity between branes reverses, anti-gravity is produced which causes that branes and identical fermions get away from each other. This is the reason for the emergence of Pauli exclusion principle in Bionic system. Also, the spinor gravity vanishes and its energy builds a new M2 between M5-branes. We obtain the resistivity in this system and find that its value decreases by closing M5 branes to each other and shrinks to zero at colliding point of branes. This idea has different applications. For example, in cosmology, universes are located on M5-branes and M2-brane has the role of bridge between
International Nuclear Information System (INIS)
Sil, Karunava; Misra, Aalok
2016-01-01
It is believed that large-N thermal QCD laboratories like strongly coupled QGP (sQGP) require not only a large 't Hooft coupling but also a finite gauge coupling (Natsuume, String theory and quark-gluon plasma. arXiv:hep-ph/0701201, 2007). Unlike almost all top-down holographic models in the literature, holographic large-N thermal QCD models, based on this assumption, therefore necessarily require addressing this limit from M-theory. This was initiated in Dhuria and Misra (JHEP 1311:001, 2013) which presented a local M-theory uplift of the string theoretic dual of large-N thermal QCD-like theories at finite gauge/string coupling of Mia et al. (Nucl. Phys. B 839:187, arXiv:0902.1540 [hep-th], 2010) (g s
Energy Technology Data Exchange (ETDEWEB)
Sil, Karunava; Misra, Aalok [Indian Institute of Technology, Department of Physics, Roorkee, Uttarakhand (India)
2016-11-15
It is believed that large-N thermal QCD laboratories like strongly coupled QGP (sQGP) require not only a large 't Hooft coupling but also a finite gauge coupling (Natsuume, String theory and quark-gluon plasma. arXiv:hep-ph/0701201, 2007). Unlike almost all top-down holographic models in the literature, holographic large-N thermal QCD models, based on this assumption, therefore necessarily require addressing this limit from M-theory. This was initiated in Dhuria and Misra (JHEP 1311:001, 2013) which presented a local M-theory uplift of the string theoretic dual of large-N thermal QCD-like theories at finite gauge/string coupling of Mia et al. (Nucl. Phys. B 839:187, arXiv:0902.1540 [hep-th], 2010) (g{sub s}
Emergence and expansion of cosmic space as due to M0-branes
Energy Technology Data Exchange (ETDEWEB)
Sepehri, Alireza [Shahid Bahonar University, Faculty of Physics, Kerman (Iran, Islamic Republic of); Research Institute for Astronomy and Astrophysics of Maragha (RIAAM), Maragha (Iran, Islamic Republic of); Setare, Mohammad Reza [University of Kurdistan, Department of Science, Bijar (Iran, Islamic Republic of); Capozziello, Salvatore [Universita di Napoli Federico II, Dipartimento di Fisica, Naples (Italy); Complutense Univ. di Monte S. Angelo, Naples (Italy); Gran Sasso Science Institute (INFN), L' Aquila (Italy); INFN Sezione di Napoli, Naples (Italy)
2015-12-15
Recently, Padmanabhan (arXiv:1206.4916 [hepth]) discussed that the difference between the number of degrees of freedom on the boundary surface and the number of degrees of freedom in a bulk region causes the accelerated expansion of the universe. The main question arising is: what is the origin of this inequality between the surface degrees of freedom and the bulk degrees of freedom? We answer this question in M-theory. In our model, first M0-branes are compactified on one circle and N D0-branes are created. Then N D0-branes join each other, grow, and form one D5-branes. Next, the D5-brane is compactified on two circles and our universe's D3-brane, two D1-branes and some extra energies are produced. After that, one of the D1-branes, which is closer to the universe's brane, gives its energy into it, and this leads to an increase in the difference between the numbers of degrees of freedom and the occurring inflation era. With the disappearance of this D1-brane, the number of degrees of freedom of boundary surface and bulk region become equal and inflation ends. At this stage, extra energies that are produced due to the compactification cause an expansion of the universe and deceleration epoch. Finally, another D1-brane dissolves in our universe's brane, leads to an inequality between degrees of freedom, and there occurs a new phase of acceleration. (orig.)
The ground state of long-range Schrödinger equations and static qq̄ potential
Energy Technology Data Exchange (ETDEWEB)
Beccaria, Matteo [Dipartimento di Matematica e Fisica Ennio De Giorgi,Università del Salento, Via Arnesano, 73100 Lecce (Italy); INFN, Via Arnesano, 73100 Lecce (Italy); Metafune, Giorgio [Dipartimento di Matematica e Fisica Ennio De Giorgi,Università del Salento, Via Arnesano, 73100 Lecce (Italy); Pallara, Diego [Dipartimento di Matematica e Fisica Ennio De Giorgi,Università del Salento, Via Arnesano, 73100 Lecce (Italy); INFN, Via Arnesano, 73100 Lecce (Italy)
2016-05-06
Motivated by the recent results in http://arxiv.org/abs/1601.05679 about the quark-antiquark potential in N=4 SYM, we reconsider the problem of computing the asymptotic weak-coupling expansion of the ground state energy of a certain class of 1d Schrödinger operators −((d{sup 2})/(dx{sup 2}))+λ V(x) with long-range potential V(x). In particular, we consider even potentials obeying ∫{sub ℝ}dx V(x)<0 with large x asymptotics V∼−a/x{sup 2}−b/x{sup 3}+⋯. The associated Schrödinger operator is known to admit a bound state for λ→0{sup +}, but the binding energy is rigorously non-analytic at λ=0. Its asymptotic expansion starts at order O(λ), but contains higher corrections λ{sup n} log{sup m} λ with all 0≤m≤n−1 and standard Rayleigh-Schrödinger perturbation theory fails order by order in λ. We discuss various analytical tools to tame this problem and provide the general expansion of the binding energy at O(λ{sup 3}) in terms of quadratures. The method is tested on a soluble potential that is fully under control, and on various non-soluble cases as well. A supersymmetric case, arising in the study of the quark-antiquark potential in N=6 ABJ(M) theory, is also exploited to provide a further non-trivial consistency check. Our analytical results confirm at third order a remarkable exponentiation of the leading infrared logarithms, first noticed in N=4 SYM where it may be proved by Renormalization Group arguments. We prove this interesting feature at all orders at the level of the Schrödinger equation for general potentials in the considered class.
Creation and evolution of compactified cosmologies
International Nuclear Information System (INIS)
Gray, J.
2002-04-01
Many theories of particle physics rely on the existence of more than three spatial dimensions. In this thesis we consider various aspects of the cosmologies associated with such theories. The extra dimensions must be hidden in some manner and in all the cases we shall consider this is achieved by the mechanism of compactification. We start by considering a possible description of the quantum mechanical creation of such universes. A consistent description of this type would be extremely desirable because it would remove the vacua selection problems which plague such theories, increasing their predictive power markedly. The formalism we employ is that due to Hartle and Hawking. We are able to illustrate a serious problem in combining this approach to quantum cosmology with higher dimensional theories. We find that, for the wide range of theories considered, the Hartle Hawking proposal predicts that we should directly observe all the dimensions of space. This is clearly inconsistent with observation. We then proceed to consider the evolution of various examples of higher dimensional cosmologies. All the examples considered contain brane sources. We start with a simple example of such a theory in order to examine an inflationary scenario that has been proposed in the literature. This scenario utilises the large extra dimensions which are possible in brane world theories in an attempt to solve some of the fine tuning problems which occur in inflationary models. Having introduced the study of the evolution of such models in a simple context we then go on to study a more realistic case. We present, with a wide variety of generalisations, cosmological solutions which are the analogues of the rolling radii solutions of string cosmology for the case where five branes are present in the bulk of the Heterotic M-theory orbifold. (author)
Superdualities, brane tensions and massive IIA/IIB duality
International Nuclear Information System (INIS)
Lavrinenko, I.V.; Lue, H.; Pope, C.N.; Stelle, K.S.
1999-01-01
The gauge transformations of p-form fields in supergravity theories acquire a non-commuting character when one introduces potentials both for the theory's original field strengths and for their duals. This has previously been shown in the 'doubled' formalism for maximal supergravities, where a generalised duality relation between original and dual field strengths replaces the equations of motion. In the doubled formalism, the gauge transformations generate a superalgebra, and the corresponding symmetries have accordingly been called 'superdualities'. The corresponding Noether charges form a representation of the cohomology ring on the space-time manifold. In this paper, we show that the gauge symmetry superalgebra implies certain non-trivial relations among the various p-brane tensions, which can straightforwardly be read off from the superalgebra commutation relations. This provides an elegant derivation of the brane-tension relations purely within a given theory, without the need to make use of duality relations between different theories, such as the type IIA/IIB T-duality, although the results are consistent with such dualities. We present the complete set of brane-tension relations in M-theory, in the type IIA and type IIB theories, and in all the lower-dimensional maximal supergravities. We also construct a doubled formalism for massive type IIA supergravity, and this enables us to obtain the brane-tension relations involving the D8-brane, purely within the framework of the massive IIA theory. We also obtain explicit transformations for the nine-dimensional T-duality between the massive type IIA theory and the Scherk-Schwarz reduced type IIB theory
Kizilirmak, Jasmin M; Rösler, Frank; Bien, Siegfried; Khader, Patrick H
2015-07-21
The attention to memory theory (AtoM) proposes that the same brain regions might be involved in selective processing of perceived stimuli (selective attention) and memory representations (selective retrieval). Although this idea is compelling, given consistently found neural overlap between perceiving and remembering stimuli, recent comparisons brought evidence for overlap as well as considerable differences. Here, we present a paradigm that enables the investigation of the AtoM hypothesis from a novel perspective to gain further insight into the neural resources involved in AtoM. Selective attention in perception is often investigated as a control process that shows lingering effects on immediately following trials. Here, we employed a paradigm capable of modulating selective retrieval in a similarly dynamic manner as in such selective-attention paradigms by inducing trial-to-trial shifts between relevant and irrelevant memory representations as well as changes of the width of the internal focus on memory. We found evidence for an involvement of bilateral inferior parietal lobe and right inferior frontal gyrus in reorienting the attentional focus on previously accessed memory representations. Moreover, we could dissociate the right inferior from the parietal activation in separate contrasts, suggesting that the right inferior frontal gyrus plays a role in facilitating attentional reorienting to memory representations when competing representations have been activated in the preceding trial, potentially by resolving this competition. Our results support the AtoM theory, i.e. that ventral frontal and parietal regions are involved in automatic attentional reorienting in memory, and highlight the importance of further investigations of the overlap and differences between regions involved in internal (memory) and external (perceptual) attentional selection. Copyright © 2015 Elsevier B.V. All rights reserved.
Aspects of T-Dually Extended Superspaces
Polacek, Martin
This dissertation is divided into three main parts where we derive various properties of the T-dually extended superspaces. In the first part we reformulate the manifestly T-dual description of the massless sector of the closed bosonic string, directly from the geometry associated with the (left and right) affine Lie algebra of the coset space Poincare/Lorentz. This construction initially doubles not only the (space-time) coordinates for translations but also those for Lorentz transformations (and their "dual"). As a result, the Lorentz connection couples directly to the string (as does the vielbein), rather than being introduced indirectly through covariant derivatives as previously. This not only reproduces the old definition of T-dual torsion, but automatically gives a general, covariant definition of T-dual curvature (but still with some undetermined connections). In the second part we give the manifestly T-dual formulation of the massless sector of the classical 3D Type II superstring in off-shell 3D N = 2 superspace, including the action. It has a simple relation to the known superspace of 4D N = 1 supergravity in 4D M-theory via 5D F-theory. The pre-potential appears as part of the vielbein, without derivatives. In the last and the most involved part we find the pre-potential in the superspace with AdS5 x S5 background. The pre-potential appears as part of the vielbeins, without derivatives. In both subspaces (AdS5 and S 5) we use Poincare coordinates. We pick one bulk coordinate in AdS5 and one bulk coordinate in S 5 to define the space-cone gauge. Such space-cone gauge destroys the bulk Lorentz covariance. However, it still preserves boundary Lorentz covariance (and gives projective superspace) SO ( 3, 1) ⊗ SO (4) and so symmetries of boundary CFT are manifest.
The spinorial geometry of supersymmetric backgrounds
International Nuclear Information System (INIS)
Gillard, J; Gran, U; Papadopoulos, G
2005-01-01
We propose a new method to solve the Killing spinor equations of 11-dimensional supergravity based on a description of spinors in terms of forms and on the Spin(1, 10) gauge symmetry of the supercovariant derivative. We give the canonical form of Killing spinors for backgrounds preserving two supersymmetries, N = 2, provided that one of the spinors represents the orbit of Spin(1, 10) with stability subgroup SU(5). We directly solve the Killing spinor equations of N = 1 and some N = 2, N = 3 and N = 4 backgrounds. In the N = 2 case, we investigate backgrounds with SU(5) and SU(4) invariant Killing spinors and compute the associated spacetime forms. We find that N = 2 backgrounds with SU(5) invariant Killing spinors admit a timelike Killing vector and that the space transverse to the orbits of this vector field is a Hermitian manifold with an SU(5)-structure. Furthermore, N = 2 backgrounds with SU(4) invariant Killing spinors admit two Killing vectors, one timelike and one spacelike. The space transverse to the orbits of the former is an almost Hermitian manifold with an SU(4)-structure. The spacelike Killing vector field leaves the almost complex structure invariant. We explore the canonical form of Killing spinors for backgrounds preserving more than two supersymmetries, N > 2. We investigate a class of N = 3 and N = 4 backgrounds with SU(4) invariant spinors. We find that in both cases the space transverse to a timelike vector field is a Hermitian manifold equipped with an SU(4)-structure and admits two holomorphic Killing vector fields. We also present an application to M-theory Calabi-Yau compactifications with fluxes to one dimension
The spinorial geometry of supersymmetric backgrounds
Energy Technology Data Exchange (ETDEWEB)
Gillard, J; Gran, U; Papadopoulos, G [Department of Mathematics, King' s College London, Strand, London WC2R 2LS (United Kingdom)
2005-03-21
We propose a new method to solve the Killing spinor equations of 11-dimensional supergravity based on a description of spinors in terms of forms and on the Spin(1, 10) gauge symmetry of the supercovariant derivative. We give the canonical form of Killing spinors for backgrounds preserving two supersymmetries, N = 2, provided that one of the spinors represents the orbit of Spin(1, 10) with stability subgroup SU(5). We directly solve the Killing spinor equations of N = 1 and some N = 2, N = 3 and N = 4 backgrounds. In the N = 2 case, we investigate backgrounds with SU(5) and SU(4) invariant Killing spinors and compute the associated spacetime forms. We find that N = 2 backgrounds with SU(5) invariant Killing spinors admit a timelike Killing vector and that the space transverse to the orbits of this vector field is a Hermitian manifold with an SU(5)-structure. Furthermore, N = 2 backgrounds with SU(4) invariant Killing spinors admit two Killing vectors, one timelike and one spacelike. The space transverse to the orbits of the former is an almost Hermitian manifold with an SU(4)-structure. The spacelike Killing vector field leaves the almost complex structure invariant. We explore the canonical form of Killing spinors for backgrounds preserving more than two supersymmetries, N > 2. We investigate a class of N = 3 and N = 4 backgrounds with SU(4) invariant spinors. We find that in both cases the space transverse to a timelike vector field is a Hermitian manifold equipped with an SU(4)-structure and admits two holomorphic Killing vector fields. We also present an application to M-theory Calabi-Yau compactifications with fluxes to one dimension.
Holomorphic couplings in non-perturbative string compactifications
Energy Technology Data Exchange (ETDEWEB)
Klevers, Denis Marco
2011-06-15
In this thesis we present an analysis of several aspects of four-dimensional, non-perturbative N = 1 compactifications of string theory. Our focus is on the study of brane dynamics and their effective physics as encoded in the holomorphic couplings of the low-energy N=1 effective action, most prominently the superpotential W. The thesis is divided into three parts. In part one we derive the effective action of a spacetime-filling D5-brane in generic Type IIB Calabi-Yau orientifold compactifications. In the second part we invoke tools from string dualities, namely from F-theory, heterotic/F-theory duality and mirror symmetry, for a more elaborate study of the dynamics of (p, q) 7-branes and heterotic five-branes. In this context we demonstrate exact computations of the complete perturbative effective superpotential, both due to branes and background fluxes. Finally, in the third part we present a novel geometric description of five-branes in Type IIB and heterotic M-theory Calabi-Yau compactifications via a non-Calabi-Yau threefold Z{sub 3}, that is canonically constructed from the original five-brane and Calabi-Yau threefold Z{sub 3} via a blow-up. We exploit the use of the blow-up threefold Z{sub 3} as a tool to derive open-closed Picard-Fuchs differential equations, that govern the complete effective brane and flux superpotential. In addition, we present first evidence to interpret Z{sub 3} as a flux compactification dual to the original five-brane by defining an SU(3)-structure on Z{sub 3}, that is generated dynamically by the five-brane backreaction. (orig.)
International Nuclear Information System (INIS)
Hawking, S.
2002-01-01
In this new book Hawking takes us to the cutting edge of theoretical physics, where truth is often stranger than fiction, to explain in laymen's terms the principles that control our universe. Like many in the community of theoretical physicists, Professor Hawking is seeking to uncover the grail of science -- the elusive Theory of Everything that lies at the heart of the cosmos. In his accessible and often playful style, he guides us on his search to uncover the secrets of the universe -- from supergravity to supersymmetry, from quantum theory to M-theory, from holography to duality. He takes us to the wild frontiers of science, where superstring theory and p-branes may hold the final clue to the puzzle. And he lets us behind the scenes of one of his most exciting intellectual adventures as he seeks t o combine Einstein's General Theory of Relativity and Richard Feynman's idea of multiple histories into one complete unified theory that will describe everything that happens in the universe. 'With characteristic exuberance, Professor Hawking invites us to be fellow travelers on this extraordinary voyage through space-time'. Copious four-color illustrations help clarify this journey into a surreal wonderland where particles, sheets, and strings move in eleven dimensions; where black holes evaporate and disappear, taking their secret with them; and where the original cosmic seed from which our own universe sprang was a tiny nut. The Universe in a Nutshell is essential reading for all of us who want to understand the universe in which we live
Aspects of some dualities in string theory
Kim, Bom Soo
AdS/CFT correspondence in string theory has changed landscape of the theoretical physics. Through this celebrated duality between gravity theory and field theory, one can investigate analytically strongly coupled gauge theories such as Quantum Chromodynamics (QCD) in terms of weakly coupled string theory such as supergravity theory and vice versa. In the first part of this thesis we used this duality to construct a new type of nonlocal field theory, called Puff Field Theory, in terms of D3 branes in type IIB string theory with a geometric twist. In addition to the strong-weak duality of AdS/CFT, there also exists a weak-weak duality, called Twistor String Theory. Twistor technique is successfully used to calculate the SYM scattering amplitude in an elegant fashion. Yet, the progress in the string theory side was hindered by a non-unitary conformal gravity. We extend the Twistor string theory by introducing mass terms, in the second part of the thesis. A chiral mass term is identified as a vacuum expectation value of a conformal supergravity field and is tied with the breaking of the conformal symmetry of gravity. As a prime candidate for a quantum theory of gravity, string theory revealed many promising successes such as counting the number of microstates in supersymmetric Black Holes thermodynamics and resolution of timelike and null singularities, to name a few. Yet, the fundamental string and M-theroy formulations are not yet available. Various string theories without gravity, such as Non-Commutative Open String (NCOS) and Open Membrane (OM) theories, are very nice playground to investigate the fundamental structure of string and M-theory without the complication of gravity. In the last part of the thesis, simpler Non-Relativistic String Theories are constructed and investigated. One important motivation for those theories is related to the connection between Non-Relativistic String Theories and Non-critical String Theories through the bosonization of betagamma
Holomorphic couplings in non-perturbative string compactifications
International Nuclear Information System (INIS)
Klevers, Denis Marco
2011-06-01
In this thesis we present an analysis of several aspects of four-dimensional, non-perturbative N = 1 compactifications of string theory. Our focus is on the study of brane dynamics and their effective physics as encoded in the holomorphic couplings of the low-energy N=1 effective action, most prominently the superpotential W. The thesis is divided into three parts. In part one we derive the effective action of a spacetime-filling D5-brane in generic Type IIB Calabi-Yau orientifold compactifications. In the second part we invoke tools from string dualities, namely from F-theory, heterotic/F-theory duality and mirror symmetry, for a more elaborate study of the dynamics of (p, q) 7-branes and heterotic five-branes. In this context we demonstrate exact computations of the complete perturbative effective superpotential, both due to branes and background fluxes. Finally, in the third part we present a novel geometric description of five-branes in Type IIB and heterotic M-theory Calabi-Yau compactifications via a non-Calabi-Yau threefold Z 3 , that is canonically constructed from the original five-brane and Calabi-Yau threefold Z 3 via a blow-up. We exploit the use of the blow-up threefold Z 3 as a tool to derive open-closed Picard-Fuchs differential equations, that govern the complete effective brane and flux superpotential. In addition, we present first evidence to interpret Z 3 as a flux compactification dual to the original five-brane by defining an SU(3)-structure on Z 3 , that is generated dynamically by the five-brane backreaction. (orig.)
ToE in a nutshell or reconciliation of Bohr and Einstein
Energy Technology Data Exchange (ETDEWEB)
Kaesser, Juergen
2016-07-01
Unification of particle and gravitational physics is today's major challenge. This book describes a comprehensive theory able to accomplish it. Starting with a few basic assumptions it allows deducting so different features as e.g. the forces, the six quarks, particle mass etc. of the Standard Model or light deflection, perihelion rotation, Shapiro effect, red shift etc. of General Relativity. Furthermore among others it gives answers to open questions like GUT, Dark Mass and eventually Dark Energy, justifies why the behavior of elementary particles in a gravitational field complies with the Schroedinger equation or why the radii of the planets in our solar system are as they are. Einstein and Bohr fiercely struggled for an understanding of quantum physics. Their different perspectives seem to be irreconcilable. Because of the overwhelming success of quantum physics the dissent unsettling the foundation of physics was never resolved. Doing it, as it is tried in this book, comprehensibility for physical processes is regained. Paradoxes like Schroedinger's Cat vanish into thin air. A theory of unification cannot be simple as it has to contain the known physics. Moreover it has to overcome their contradictions as in defining space-time or in postulating separability. Advantage of the here presented approach compared to M-theory or Loop Quantum Gravitation is its ability to deduct observable features. Of course open questions remain being answered requiring the computational effort of actual theories if not even much more. But these items do not define the basic message of the theory but the derivation of specifics.
Moduli effective action in warped brane-world compactifications
International Nuclear Information System (INIS)
Garriga, Jaume; Pujolas, Oriol; Tanaka, Takahiro
2003-01-01
We consider a class of 5D brane-world solutions with a power-law warp factor a(y)∝y q , and bulk dilaton with profile phi∝lny, where y is the proper distance in the extra dimension. This class includes the heterotic M-theory brane-world of [Phys. Rev. D 59 (1999) 086001, and] and the Randall-Sundrum (RS) model as a limiting case. In general, there are two moduli fields y ± , corresponding to the 'positions' of two branes (which live at the fixed points of an orbifold compactification). Classically, the moduli are massless, due to a scaling symmetry of the action. However, in the absence of supersymmetry, they develop an effective potential at one loop. Local terms proportional to K ± 4 , where K ± =q/y ± is the local curvature scale at the location of the corresponding brane, are needed in order to remove the divergences in the effective potential. Such terms break the scaling symmetry and hence they may act as stabilizers for the moduli. When the branes are very close to each other, the effective potential induced by massless bulk fields behaves like V∼d -4 , where d is the separation between branes. When the branes are widely separated, the potentials for each one of the moduli generically develop a 'Coleman-Weinberg'-type behaviour of the form a 4 (y ± )K ± 4 ln(K ± /μ ± ), where μ ± are renormalization scales. In the RS case, the bulk geometry is AdS and K ± are equal to a constant, independent of the position of the branes, so these terms do not contribute to the mass of the moduli. However, for generic warp factor, they provide a simple stabilization mechanism. For q > or approx. 10, the observed hierarchy can be naturally generated by this potential, giving the lightest modulus a mass of order m - < or approx. TeV
On (orientifold of) type IIA on a compact Calabi-Yau
International Nuclear Information System (INIS)
Misra, A.
2004-01-01
We study the gauged sigma model and its mirror Landau-Ginsburg model corresponding to type IIA on the Fermat degree-24 hypersurface in WCP 4 [1,1,2,8,12] (whose blow-up gives the smooth CY 3 (3,243)) away from the orbifold singularities, and its orientifold by a freely-acting antiholomorphic involution. We derive the Picard-Fuchs equation obeyed a period integral of a parent N=2 type IIA theory. We obtain the Meijer's basis of solutions to the equation in the large and small complex structure limits (on the mirror Landau-Ginsburg side) of the abovementioned Calabi-Yau, and make some remarks about the monodromy properties associated at the same and another MATHEMATICAlly interesting point. Based on a recently shown N=1 four-dimensional triality between Heterotic on the self-mirror Calabi-Yau CY 3 (11,11), M theory on CY 3 (3,243) x S 1 /(Z 2 ) and F-theory on an elliptically fibered CY 4 with the base given by CP 1 x Enriques surface, we first give a heuristic argument that there can be no superpotential generated in the orientifold of of CY 3 (3,243), and then explicitly verify the same using a mirror symmetry formulation for the abovementioned hypersurface away from its orbifold singularities. We then discuss briefly the sigma model and the mirror Landau-Ginsburg model corresponding to the resolved Calabi-Yau as well. (Abstract Copyright [2004], Wiley Periodicals, Inc.)
Experiences that inspire hope: Perspectives of suicidal patients.
Vatne, May; Nåden, Dagfinn
2018-06-01
Suffering in a suicidal crisis includes feelings such as despair, loneliness, anxiety, fear, shame, guilt and hopelessness. This study highlights the experiences of patients in the aftermath of suicide attempts. The research question was, what do suicidal patients see as meaningful help in care and treatment situations? The methodology is inspired by Gadamer's hermeneutics, where the parts are understood in light of the whole, and the whole is understood in light of the parts. Qualitative interviews were employed. Participants and research context: A total of 10 persons, 4 women and 6 men 21-52 years old, were informed and asked to participate by specialists in psychology at two emergency psychiatric wards and by one crisis resolution team. Nine of the participants had experienced one or more suicide attempts using drugs and alcohol. Forced hospitalization prevented one of the 10 participants from attempting suicide. Ethical considerations: Before the participants signed an informed consent form, the interviewer met all participants to provide the written information, talking about the interview. A meeting to terminate contact was arranged after the participants had read their own interviews. Three themes were generated by the methodology we applied: (1) experiencing hope through encounters, (2) experiencing hope through the atmosphere of wisdom and (3) experiencing a ray of hope from taking back responsibility. The findings are discussed in the light of Eriksson's suffering theory and Lindström's theory about psychiatric care, as well as earlier research and theories about suicidality. The study reinforces possibilities that hope in suicidal patients can be inspired in encounters with healthcare personnel and within caring cultures. Through dialogue and cooperation, patients' safety and ability to cope with suffering is created and thereby the hope and will to struggle for life.
Predicted and Totally Unexpected in the Energy Frontier Opened by LHC
Zichichi, Antonino
2011-01-01
Opening lectures. Sid Coleman and Erice / A. Zichichi. Remembering Sidney Coleman / G.'t Hooft -- Predicted signals at LHC. From extra-dimensions: Multiple branes scenarios and their contenders / I. Antoniadis. Predicted signals at the LHC from technicolor / A. Martin. The one-parameter model at LHC / J. Maxin, E. Mayes and D. V. Nanopoulos. How supercritical string cosmology affects LHC / D. V. Nanopoulos. High scale physics connection to LHC data / P. Nath. Predicted signatures at the LHC from U(I) extensions of the standard model / P. Nath -- Hot theoretical topics. Progress on the ultraviolet finiteness of supergravity / Z. Bern. Status of supersymmetry: Foundations and applications / S. Ferrara and A. Marrani. Quantum gravity from dynamical triangulation / R. Loll. Status of superstring and M-theory / J. H. Schwarz. Some effects of instantons in QCD / G.'t Hooft. Crystalline gravity / G.'t Hooft -- QCD problems. Strongly coupled gauge theories / R. Kenway. Strongly interacting matter at high energy density / L. McLerran. Seminars on specialized topics. The nature and the mass of neutrinos. Majorana vs. Dirac / A. Bettini. The anomalous spin distributions in the nucleon / A. Deshpande. Results from PHENIX at RHIC / M. J. Tannenbaum -- Highlights from laboratories. Highlights from RHIC / Y. Akiba. News from the Gran Sasso Underground Laboratory / E. Coccia. Highlights from TRIUMF / N. S. Lockyer. Highlights from Superkamiokande / M. Koshiba. Highlights from Fermilab / P. J. Oddone. Highlights from IHEP / Y. Wang -- Special sessions for new talents. Fake supergravity and black hole evolution / A. Gnecchi. Track-based improvement in the jet transverse momentum resolution for ATLAS / Z. Marshall. Searches for supersymmetric dark matter with XENON / K. Ni. Running of Newton's constant and quantum gravitational effects / D. Reeb.
Teleparallel loop quantum cosmology in a system of intersecting branes
Directory of Open Access Journals (Sweden)
Alireza Sepehri
2016-09-01
Full Text Available Recently, some authors have removed the big bang singularity in teleparallel Loop Quantum Cosmology (LQC and have shown that the universe may undergo a number of oscillations. We investigate the origin of this type of teleparallel theory in a system of intersecting branes in M-theory in which the angle between them changes with time. This system is constructed by two intersecting anti-D8-branes, one compacted D4-brane and a D3-brane. These branes are built by joining M0-branes which develop in decaying fundamental strings. The compacted D4-brane is located between two intersecting anti-D8 branes and glues to one of them. Our universe is located on the D3 brane which wraps around the D4 brane from one end and sticks to one of the anti-D8 branes from the other one. In this system, there are three types of fields, corresponding to compacted D4 branes, intersecting branes and D3-branes. These fields interact with each other and make the angle between branes oscillate. By decreasing this angle, the intersecting anti-D8 branes approach each other, the D4 brane rolls, the D3 brane wraps around the D4 brane, and the universe contracts. By separating the intersecting branes and increasing the angle, the D4 brane rolls in the opposite direction, the D3 brane separates from it and the expansion branch begins. Also, the interaction between branes in this system gives us the exact form of the relevant Lagrangian for teleparallel LQC.
Teleparallel loop quantum cosmology in a system of intersecting branes
Energy Technology Data Exchange (ETDEWEB)
Sepehri, Alireza, E-mail: alireza.sepehri@uk.ac.ir [Faculty of Physics, Shahid Bahonar University, P.O. Box 76175, Kerman (Iran, Islamic Republic of); Research Institute for Astronomy and Astrophysics of Maragha (RIAAM), P.O. Box 55134-441, Maragha (Iran, Islamic Republic of); Pradhan, Anirudh, E-mail: pradhan.anirudh@gmail.com [Department of Mathematics, Institute of Applied Sciences and Humanities, GLA University, Mathura-281 406, Uttar Pradesh (India); Beesham, Aroonkumar, E-mail: beeshama@unizulu.ac.za [Department of Mathematical Sciences, University of Zululand, Kwa-Dlangezwa 3886 (South Africa); Haro, Jaume de, E-mail: jaime.haro@upc.edu [Departament de Matemàtiques, Universitat Politècnica de Catalunya, Diagonal 647, 08028 Barcelona (Spain)
2016-09-10
Recently, some authors have removed the big bang singularity in teleparallel Loop Quantum Cosmology (LQC) and have shown that the universe may undergo a number of oscillations. We investigate the origin of this type of teleparallel theory in a system of intersecting branes in M-theory in which the angle between them changes with time. This system is constructed by two intersecting anti-D8-branes, one compacted D4-brane and a D3-brane. These branes are built by joining M0-branes which develop in decaying fundamental strings. The compacted D4-brane is located between two intersecting anti-D8 branes and glues to one of them. Our universe is located on the D3 brane which wraps around the D4 brane from one end and sticks to one of the anti-D8 branes from the other one. In this system, there are three types of fields, corresponding to compacted D4 branes, intersecting branes and D3-branes. These fields interact with each other and make the angle between branes oscillate. By decreasing this angle, the intersecting anti-D8 branes approach each other, the D4 brane rolls, the D3 brane wraps around the D4 brane, and the universe contracts. By separating the intersecting branes and increasing the angle, the D4 brane rolls in the opposite direction, the D3 brane separates from it and the expansion branch begins. Also, the interaction between branes in this system gives us the exact form of the relevant Lagrangian for teleparallel LQC.
Perspectives on the Logos’ immanence in Creation
Directory of Open Access Journals (Sweden)
Nicolae Moșoiu
2016-03-01
Full Text Available „The reasons of things that God prepared in advance for ages, as He Himself knew, can be seen through understanding from the creatures. For every creature of God, contemplated by us through nature, using science and knowledge, proclaim in a hidden manner the reasons after which they were made and they reveal the purpose placed by God in every creature. From the wise contemplation of creation we can perceive the Reason which enlightens us about the Holy Trinity, i.e. the Father, the Son and the Holy Spirit” [1]. Abstract: The article deals with the theme of the Logos` immanence in the creation. The first part includes a scientific perspective while the second, a theological one. The first evidence that the universe has a beginning dates back to the 20s of last century. Most scientists believed until then that the universe was stationary and had always existed; there are references to the big bang, string theory, M theory. The second part encompasses a perspective on the theme of the rational nature of the world which constitutes a firm foundation for dialogue between Theology and science. The logoi have a particularizing or a unifing function, and the complete unity of the logoi is realized through and by the Logos, the Word of God. The essential difference between paradigms and logoi is that the latter belong to the temporal level and to the empirical world, while the former preexist synthetically into God.The uncreated divine energies are the logoi in the action of creating and supporting of the beings.
A profusion of 1/2 BPS Wilson loops in N=4 Chern-Simons-matter theories
International Nuclear Information System (INIS)
Cooke, Michael; Drukker, Nadav; Trancanelli, Diego
2015-01-01
We initiate the study of 1/2 BPS Wilson loops in N=4 Chern-Simons-matter theories in three dimensions. We consider a circular or linear quiver with Chern-Simons levels k, −k and 0, and focus on loops preserving one of the two SU(2) subgroups of the R-symmetry. In the cases with no vanishing Chern-Simons levels, we find a pair of Wilson loops for each pair of adjacent nodes on the quiver connected by a hypermultiplet (nodes connected by twisted hypermultiplets have Wilson loops preserving another set of supercharges). We expect this classical pairwise degeneracy to be lifted by quantum corrections. In the case with nodes with vanishing Chern-Simons terms connected by twisted hypermultiplets, we find that the usual 1/4 BPS Wilson loops are automatically enlarged to 1/2 BPS, as happens also in 3-dimensional Yang-Mills theory. When the nodes with vanishing Chern-Simons levels are connected by untwisted hypermultiplets, we do not find any Wilson loops coupling to those nodes which are classically invariant. Rather, we find several loops whose supersymmetry variation, while non zero, vanishes in any correlation function, so is weakly zero. We expect only one linear combination of those Wilson loops to remain BPS when quantum corrections are included. We analyze the M-theory duals of those Wilson loops and comment on their degeneracy. We also show that these Wilson loops are cohomologically equivalent to certain 1/4 BPS Wilson loops whose expectation value can be evaluated by the appropriate localized matrix model.
Noncommutativity into Dirac Equation with mass dependent on the position
International Nuclear Information System (INIS)
Bastos, Samuel Batista; Almeida, Carlos Alberto Santos; Nunes, Luciana Angelica da Silva
2013-01-01
Full text: In recent years, there is growing interest in the study of theories in non-commutative spaces. Non-commutative fields theories are related with compactifications of M theory, string theory and the quantum Hall effect. Moreover, the role of the non-commutativity of theories of a particle finds large applications when analyzed in scenarios of quantum mechanics and relativistic quantum mechanics. In these contexts investigations on the Schrodinger and Dirac equations with mass depending on the position (MDP) has attracted much attention in the literature. Systems endowed with MDP models are useful for the study of many physical problems. In particular, they are used to study the energy density in problems of many bodies, determining the electronic properties of semiconductor heterostructures and also to describe the properties of heterojunctions and quantum dots. In particular, the investigation of relativistic effects it is important for systems containing heavy atoms or doping by heavy ions. For these types of materials, the study of the properties of the Dirac equation, in the case where the mass becomes variable is of great interest. In this paper, we seek for the non-relativistic limit of the Dirac Hamiltonian in the context of a theory of effective mass, through a Foldy-Wouthuysen transformation. We analyse the Dirac equation with mass dependent on the position, in a smooth step shape mass distribution, in non-commutative space (NC). This potential type kink was recently discussed by several authors in the commutative context and now we present our results in the non-commutative context. (author)
Cosmic string solution in a Born-Infeld type theory of gravity
International Nuclear Information System (INIS)
Rocha, W.J. da; Guimaraes, M.E.X.
2009-01-01
Full text. Advances in the formal structure of string theory point to the emergence, and necessity, of a scalar-tensorial theory of gravity. It seems that, at least at high energy scales, the Einstein's theory is not enough to explain the gravitational phenomena. In other words, the existence of a scalar (gravitational) field acting as a mediator of the gravitational interaction together with the usual purely rank-2 tensorial field is, indeed, a natural prediction of unification models as supergravity, superstrings and M-theory. This type of modified gravitation was first introduced in a different context in the 60's in order to incorporate the Mach's principle into relativity, but nowadays it acquired different sense in cosmology and gravity theories. Although such unification theories are the most acceptable, they all exist in higher dimensional spaces. The compactification from these higher dimensions to the 4-dimensional physics is not unique and there exist many effective theories of gravity which come from the unification process. Each of them must, of course, satisfy some predictions. Here, in this paper, we will deal with one of them. The so-called NDL theory. One important assumption in General Relativity is that all field interact in the same way with gravity. This is the so called Strong Equivalence Principle (SEP). It is well known, with good accuracy, that this is true when we concern with matter to matter interaction, i.e, the Weak Equivalence Principle(WEP) is tested. But, until now, there is no direct observational confirmation of this affirmation to the gravity to gravity interaction. In an extension of the field theoretical description of General Relativity constructed by is used to propose an alternative field theory of gravity. In this theory gravitons propagate in a different spacetime. The velocity of propagation of the gravitational waves in this theory does not coincide with the General Relativity predictions. (author)
New complete noncompact Spin(7) manifolds
International Nuclear Information System (INIS)
Cvetic, M.; Gibbons, G.W.; Lue, H.; Pope, C.N.
2002-01-01
We construct new explicit metrics on complete noncompact Riemannian 8-manifolds with holonomy Spin(7). One manifold, which we denote by (A 8 , is topologically R 8 and another, which we denote by B 8 , is the bundle of chiral spinors over S 4 . Unlike the previously-known complete noncompact metric of Spin(7) holonomy, which was also defined on the bundle of chiral spinors over S 4 , our new metrics are asymptotically locally conical (ALC): near infinity they approach a circle bundle with fibres of constant length over a cone whose base is the squashed Einstein metric on CP 3 . We construct the covariantly-constant spinor and calibrating 4-form. We also obtain an L 2 -normalisable harmonic 4-form for the (A)) 8 manifold, and two such 4-forms (of opposite dualities) for the B 8 manifold. We use the metrics to construct new supersymmetric brane solutions in M-theory and string theory. In particular, we construct resolved fractional M2-branes involving the use of the L 2 harmonic 4-forms, and show that for each manifold there is a supersymmetric example. An intriguing feature of the new A 8 and B 8 Spin(7) metrics is that they are actually the same local solution, with the two different complete manifolds corresponding to taking the radial coordinate to be either positive or negative. We make a comparison with the Taub-NUT and Taub-BOLT metrics, which by contrast do not have special holonomy. In we construct the general solution of our first-order equations for Spin(7) holonomy, and obtain further regular metrics that are complete on manifolds B 8 + and B 8 - similar to B 8
From the big bang to the eureka moment
Energy Technology Data Exchange (ETDEWEB)
Rodgers, Peter
2002-02-01
. Hawking told the meeting that he wants this simple equation (S = Akc3/4h-bar G) to be on his tombstone. Hawking then went on to predict that black holes have a temperature and are not, therefore, completely black. In simple terms, what is now known as Hawking radiation is produced when quantum fluctuations give rise to pairs of short-lived virtual particles near the event horizon. The gravity of the black hole pulls one of the particles from each pair into the black hole, while the other escapes. From a distance it appears as if the black hole is radiating. This effect was symbolized by the conference mug, which changes from black to white to reveal the equation for the Hawking temperature when it is filled with hot tea or coffee. One speaker showed the meeting a list of Hawking's papers in the SPIRES database at the Stanford Linear Accelerator Center. Six of Hawking's papers have qualified for 'renowned' status, having been cited more than 500 times by other papers in the database. The paper on Hawking radiation had the most citations, followed by a paper with Jim Hartle on the initial wavefunction of the universe, and a paper on the inflationary theory of the early universe. The struggle to develop a quantum theory of gravity and to unify the four fundamental forces of nature was an overarching theme at the conference. Most theorists believe that the best approach is so-called M-theory, in which the fundamental particles are actually vibrations in tiny strings in a 11-dimensional space-time. So far theorists know that M-theory embraces a classical theory known as 11-dimensional supergravity and all five of the superstring theories that were previously candidates for a unified theory. However, they do not yet know how to apply M-theory to the real universe. (U.K.)
Nonperturbative type IIB model building in the F-theory framework
International Nuclear Information System (INIS)
Jurke, Benjamin Helmut Friedrich
2011-01-01
This dissertation is concerned with the topic of non-perturbative string theory, which is generally considered to be the most promising approach to a consistent description of quantum gravity. The five known 10-dimensional perturbative string theories are all interconnected by numerous dualities, such that an underlying non-perturbative 11-dimensional theory, called M-theory, is postulated. Due to several technical obstacles, little is known about the fundamental objects in this theory. There exists an alternative non-perturbative description to type IIB string theory, namely F-theory. Here the SL(2;Z) self-duality of IIB theory is geometrized in the form of an elliptic fibration over the space-time. Moreover, higher-dimensional objects like 7-branes are included via singularities into the geometric picture. This formally elegant description, however, requires significant technical effort for the construction of suitable compactification geometries, as many different aspects necessarily have to be dealt with at the same time. On the other hand, the generation of essential GUT building blocks like certain Yukawa couplings or spinor representations is easier compared to perturbative string theory. The goal of this study is therefore to formulate a unified theory within the framework of F-theory, that satisfies basic phenomenological constraints. Within this thesis, at first E3-brane instantons in type IIB string theory - 4-dimensional objects that are entirely wrapped around the invisible dimensions of space-time - are matched with M5-branes in F-theory. Such objects are of great importance in the generation of critical Yukawa couplings or the stabilization of the free parameters of a theory. Certain properties of M5-branes then allow to derive a new criterion for E3-branes to contribute to the superpotential. In the aftermath of this analysis, several compactification geometries are constructed and checked for basic properties that are relevant for semi
Extended charged events and Chern-Simons couplings
International Nuclear Information System (INIS)
Bunster, Claudio; Gomberoff, Andres; Henneaux, Marc
2011-01-01
In three spacetime dimensions, the world volume of a magnetic source is a single point, a magnetically charged event. It has been shown long ago that in three-dimensional spacetime, the Chern-Simons coupling is quantized, because the magnetic event emits an electric charge which must be quantized according to the standard Dirac rule. Recently, the concept of dynamical extended charged events has been introduced, and it has been argued that they should play as central a role as that played by particles or ordinary branes. In this article, we show that in the presence of a Chern-Simons coupling, a magnetically charged extended event emits an extended object, which geometrically is just like a Dirac string, but it is observable, obeys equations of motion, and may be electrically charged. We write a complete action principle which accounts for this effect. The action involves two Chern-Simons terms, one integrated over spacetime and the other integrated over the world volume of the submanifold that is the union of the Dirac world sheet and the history of the emitted physical object. By demanding that the total charge emitted by a composite extended magnetic event be quantized according to Dirac's rule, we find a quantization condition for the Chern-Simons coupling. For a 1-form electric potential in D=2n+1 spacetime dimensions, the composite event is formed by n elementary extended magnetic events separated in time such that the product of their transverse spaces, together with the time axis, is the entire spacetime. We show that the emitted electric charge is given by the integral of the (n-1)-th exterior power of the electromagnetic field strength over the last elementary event, or, equivalently, over an appropriate closed surface. The extension to more general p-form potentials and higher dimensions is also discussed. For the case D=11, p=3, our result for the quantization of the Chern-Simons coupling was obtained previously in the context of M theory, an agreement
Energy Technology Data Exchange (ETDEWEB)
McGreevy, John Austen; /Stanford U., Phys. Dept.
2005-07-06
This thesis is a study of D-branes in string compactifications. In this context, D-branes are relevant as an important component of the nonperturbative spectrum, as an incisive probe of these backgrounds, and as a natural stringy tool for localizing gauge interactions. In the first part of the thesis, we discuss half-BPS D-branes in compactifications of type II string theory on Calabi-Yau threefolds. The results we describe for these objects are pertinent both in their role as stringy brane-worlds, and in their role as solitonic objects. In particular, we determine couplings of these branes to the moduli determining the closed-string geometry, both perturbatively and non-perturbatively in the worldsheet expansion. We provide a local model for transitions in moduli space where the BPS spectrum jumps, and discuss the extension of mirror symmetry between Calabi-Yau manifolds to the case when D-branes are present. The next section is an interlude which provides some applications of D-branes to other curved backgrounds of string theory. In particular, we discuss a surprising phenomenon in which fundamental strings moving through background Ramond-Ramond fields dissolve into large spherical D3-branes. This mechanism is used to explain a previously-mysterious fact discovered via the AdS-CFT correspondence. Next, we make a connection between type IIA string vacua of the type discussed in the first section and M-theory compactifications on manifolds of G{sub 2} holonomy. Finally we discuss constructions of string vacua which do not have large radius limits. In the final part of the thesis, we develop techniques for studying the worldsheets of open strings ending on the curved D-branes studied in the first section. More precisely, we formulate a large class of massive two-dimensional gauge theories coupled to boundary matter, which flow in the infrared to the relevant boundary conformal field theories. Along with many other applications, these techniques are used to describe
Top-down holographic G-structure glueball spectroscopy at (N)LO in N and finite coupling
Energy Technology Data Exchange (ETDEWEB)
Sil, Karunava; Yadav, Vikas; Misra, Aalok [Indian Institute of Technology, Department of Physics, Roorkee, Uttaranchal (India)
2017-06-15
The top-down type IIB holographic dual of large-N thermal QCD as constructed in Mia et al. (Nucl Phys B 839:187, 2010) involving a fluxed resolved warped deformed conifold, its delocalized type IIA Strominger-Yau-Zaslow-mirror (SYZ-mirror) as well as its M-theory uplift constructed in Dhuria and Misra (JHEP 1311:001, 2013) - both in the finite coupling g{sub s}
Gauge/gravity duality applied to condensed matter systems
International Nuclear Information System (INIS)
Ammon, Martin Matthias
2010-01-01
developed. Finally a second model for the field theory at the quantum-critical point, a Chern-Simons matter theory in (2+1) dimensions is studied more precisely. On the gravitational side thereby higher-dimensional membranes and other non-perturbative objects, so-called KK-monopoles are embedded in M-theory respectively its type IIA limit.
Top-down holographic G-structure glueball spectroscopy at (N)LO in N and finite coupling
International Nuclear Information System (INIS)
Sil, Karunava; Yadav, Vikas; Misra, Aalok
2017-01-01
The top-down type IIB holographic dual of large-N thermal QCD as constructed in Mia et al. (Nucl Phys B 839:187, 2010) involving a fluxed resolved warped deformed conifold, its delocalized type IIA Strominger-Yau-Zaslow-mirror (SYZ-mirror) as well as its M-theory uplift constructed in Dhuria and Misra (JHEP 1311:001, 2013) - both in the finite coupling g s
Top-down holographic G-structure glueball spectroscopy at (N)LO in N and finite coupling
Sil, Karunava; Yadav, Vikas; Misra, Aalok
2017-06-01
The top-down type IIB holographic dual of large- N thermal QCD as constructed in Mia et al. (Nucl Phys B 839:187, 2010) involving a fluxed resolved warped deformed conifold, its delocalized type IIA Strominger-Yau-Zaslow-mirror (SYZ-mirror) as well as its M-theory uplift constructed in Dhuria and Misra (JHEP 1311:001, 2013) - both in the finite coupling (g_s ˜ \\limits ^{Misra (JHEP 1311:001, 2013) - were shown explicitly to possess a local SU(3)/G_2-structure in Sil and Misra (Nucl Phys B 910:754, 2016). Glueballs spectra in the finite-gauge-coupling limit (and not just large 't Hooft coupling limit) - a limit expected to be directly relevant to strongly coupled systems at finite temperature such as QGP (Natsuume in String theory and quark-gluon plasma, 2007) - has thus far been missing in the literature. In this paper, we fill this gap by calculating the masses of the 0^{++}, 0^{-+},0^{{-}{-}}, 1^{++}, 2^{++} (`glueball') states (which correspond to fluctuations in the dilaton or complexified two-forms or appropriate metric components) in the aforementioned backgrounds of G-structure in the `MQGP' limit of Dhuria and Misra (JHEP 1311:001, 2013). We use WKB quantization conditions on one hand and impose Neumann/Dirichlet boundary conditions at an IR cut-off (`r_0')/horizon radius (`r_h') on the solutions to the equations of motion on the other hand. We find that the former technique produces results closer to the lattice results. We also discuss the r_h=0 limits of all calculations. In this context we also calculate the 0^{++}, 0^{{-}{-}},1^{++}, 2^{++} glueball masses up to Next to Leading Order (NLO) in N and find a g_sM^2/N(g_sN_f)-suppression similar to and further validating semi-universality of NLO corrections to transport coefficients, observed in Sil and Misra (Eur Phys J C 76(11):618, 2016).
Moduli effective action in warped brane-world compactifications
Energy Technology Data Exchange (ETDEWEB)
Garriga, Jaume E-mail: garriga@ifae.es; Pujolas, Oriol; Tanaka, Takahiro
2003-04-07
We consider a class of 5D brane-world solutions with a power-law warp factor a(y){proportional_to}y{sup q}, and bulk dilaton with profile phi{proportional_to}lny, where y is the proper distance in the extra dimension. This class includes the heterotic M-theory brane-world of [Phys. Rev. D 59 (1999) 086001, and] and the Randall-Sundrum (RS) model as a limiting case. In general, there are two moduli fields y{sub {+-}}, corresponding to the 'positions' of two branes (which live at the fixed points of an orbifold compactification). Classically, the moduli are massless, due to a scaling symmetry of the action. However, in the absence of supersymmetry, they develop an effective potential at one loop. Local terms proportional to K{sub {+-}}{sup 4}, where K{sub {+-}}=q/y{sub {+-}} is the local curvature scale at the location of the corresponding brane, are needed in order to remove the divergences in the effective potential. Such terms break the scaling symmetry and hence they may act as stabilizers for the moduli. When the branes are very close to each other, the effective potential induced by massless bulk fields behaves like V{approx}d{sup -4}, where d is the separation between branes. When the branes are widely separated, the potentials for each one of the moduli generically develop a 'Coleman-Weinberg'-type behaviour of the form a{sup 4}(y{sub {+-}})K{sub {+-}}{sup 4}ln(K{sub {+-}}/{mu}{sub {+-}}), where {mu}{sub {+-}} are renormalization scales. In the RS case, the bulk geometry is AdS and K{sub {+-}} are equal to a constant, independent of the position of the branes, so these terms do not contribute to the mass of the moduli. However, for generic warp factor, they provide a simple stabilization mechanism. For q > or approx. 10, the observed hierarchy can be naturally generated by this potential, giving the lightest modulus a mass of order m{sub -} < or approx. TeV.
Nonperturbative type IIB model building in the F-theory framework
Energy Technology Data Exchange (ETDEWEB)
Jurke, Benjamin Helmut Friedrich
2011-02-28
This dissertation is concerned with the topic of non-perturbative string theory, which is generally considered to be the most promising approach to a consistent description of quantum gravity. The five known 10-dimensional perturbative string theories are all interconnected by numerous dualities, such that an underlying non-perturbative 11-dimensional theory, called M-theory, is postulated. Due to several technical obstacles, little is known about the fundamental objects in this theory. There exists an alternative non-perturbative description to type IIB string theory, namely F-theory. Here the SL(2;Z) self-duality of IIB theory is geometrized in the form of an elliptic fibration over the space-time. Moreover, higher-dimensional objects like 7-branes are included via singularities into the geometric picture. This formally elegant description, however, requires significant technical effort for the construction of suitable compactification geometries, as many different aspects necessarily have to be dealt with at the same time. On the other hand, the generation of essential GUT building blocks like certain Yukawa couplings or spinor representations is easier compared to perturbative string theory. The goal of this study is therefore to formulate a unified theory within the framework of F-theory, that satisfies basic phenomenological constraints. Within this thesis, at first E3-brane instantons in type IIB string theory - 4-dimensional objects that are entirely wrapped around the invisible dimensions of space-time - are matched with M5-branes in F-theory. Such objects are of great importance in the generation of critical Yukawa couplings or the stabilization of the free parameters of a theory. Certain properties of M5-branes then allow to derive a new criterion for E3-branes to contribute to the superpotential. In the aftermath of this analysis, several compactification geometries are constructed and checked for basic properties that are relevant for semi
AdS5 solutions from M5-branes on Riemann surface and D6-branes sources
Energy Technology Data Exchange (ETDEWEB)
Bah, Ibrahima [Department of Physics and Astronomy, University of Southern California,Los Angeles, CA 90089 (United States); Institut de Physique Théorique, CEA/Saclay,91191 Gif-sur-Yvette (France)
2015-09-24
We describe the gravity duals of four-dimensional N=1 superconformal field theories obtained by wrapping M5-branes on a punctured Riemann surface. The internal geometry, normal to the AdS{sub 5} factor, generically preserves two U(1)s, with generators (J{sup +},J{sup −}), that are fibered over the Riemann surface. The metric is governed by a single potential that satisfies a version of the Monge-Ampère equation. The spectrum of N=1 punctures is given by the set of supersymmetric sources of the potential that are localized on the Riemann surface and lead to regular metrics near a puncture. We use this system to study a class of punctures where the geometry near the sources corresponds to M-theory description of D6-branes. These carry a natural (p,q) label associated to the circle dual to the killing vector pJ{sup +}+qJ{sup −} which shrinks near the source. In the generic case the world volume of the D6-branes is AdS{sub 5}×S{sup 2} and they locally preserve N=2 supersymmetry. When p=−q, the shrinking circle is dual to a flavor U(1). The metric in this case is non-degenerate only when there are co-dimension one sources obtained by smearing M5-branes that wrap the AdS{sub 5} factor and the circle dual the superconformal R-symmetry. The D6-branes are extended along the AdS{sub 5} and on cups that end on the co-dimension one branes. In the special case when the shrinking circle is dual to the R-symmetry, the D6-branes are extended along the AdS{sub 5} and wrap an auxiliary Riemann surface with an arbitrary genus. When the Riemann surface is compact with constant curvature, the system is governed by a Monge-Ampère equation.
No-scale μ-term hybrid inflation
Energy Technology Data Exchange (ETDEWEB)
Wu, Lina [University of Electronic Science and Technology of China, School of Physical Electronics, Chengdu (China); Chinese Academy of Sciences, Key Laboratory of Theoretical Physics, Kavli Institute for Theoretical Physics China (KITPC), Institute of Theoretical Physics, Beijing (China); Hu, Shan [Hubei University, Department of Physics, Faculty of Physics and Electronic Sciences, Wuhan (China); Li, Tianjun [University of Electronic Science and Technology of China, School of Physical Electronics, Chengdu (China); Chinese Academy of Sciences, Key Laboratory of Theoretical Physics, Kavli Institute for Theoretical Physics China (KITPC), Institute of Theoretical Physics, Beijing (China); University of Chinese Academy of Sciences, School of Physical Sciences, Beijing (China)
2017-03-15
To solve the fine-tuning problem in μ-term hybrid inflation, we will realize the supersymmetry scenario with the TeV-scale supersymmetric particles and intermediate-scale gravitino from anomaly mediation, which can be consistent with the WMAP and Planck experiments. Moreover, we for the first time propose the μ-term hybrid inflation in no-scale supergravity. With four scenarios for the SU(3){sub C} x SU(2){sub L} x SU(2){sub R} x U(1){sub B-L} model, we show that the correct scalar spectral index n{sub s} can be obtained, while the tensor-to-scalar ratio r is predicted to be tiny, about 10{sup -10}-10{sup -8}. Also, the SU(2){sub R} x U(1){sub B-L} symmetry breaking scale is around 10{sup 14} GeV, and all the supersymmetric particles except gravitino are around the TeV scale, while the gravitino mass is around 10{sup 9}-10{sup 10} GeV. Considering the complete potential terms linear in S, we for the first time show that the tadpole term, which is the key for such kind of inflationary models to be consistent with the observed scalar spectral index, vanishes after inflation. Thus, to obtain the μ term, we need to generate the supersymmetry breaking soft term A{sup SΦΦ{sup '}{sub κ}} κS ΦΦ{sup '} due to A{sup SΦΦ{sup '}{sub κ}} = 0 in no-scale supergravity, where Φ and Φ{sup '} are vector-like Higgs fields at high energy. We show that the proper A{sup SΦΦ{sup '}{sub κ}} κS ΦΦ{sup '} term can be obtained in the M-theory inspired no-scale supergravity. We also point out that A{sup SΦΦ{sup '}{sub κ}} around 700 GeV can be generated via the renormalization group equation running from string scale. We briefly comment on the supersymmetry phenomenological consequences as well. (orig.)
Construction of fuzzy spaces and their applications to matrix models
Abe, Yasuhiro
Quantization of spacetime by means of finite dimensional matrices is the basic idea of fuzzy spaces. There remains an issue of quantizing time, however, the idea is simple and it provides an interesting interplay of various ideas in mathematics and physics. Shedding some light on such an interplay is the main theme of this dissertation. The dissertation roughly separates into two parts. In the first part, we consider rather mathematical aspects of fuzzy spaces, namely, their construction. We begin with a review of construction of fuzzy complex projective spaces CP k (k = 1, 2, · · ·) in relation to geometric quantization. This construction facilitates defining symbols and star products on fuzzy CPk. Algebraic construction of fuzzy CPk is also discussed. We then present construction of fuzzy S 4, utilizing the fact that CP3 is an S2 bundle over S4. Fuzzy S4 is obtained by imposing an additional algebraic constraint on fuzzy CP3. Consequently it is proposed that coordinates on fuzzy S4 are described by certain block-diagonal matrices. It is also found that fuzzy S8 can analogously be constructed. In the second part of this dissertation, we consider applications of fuzzy spaces to physics. We first consider theories of gravity on fuzzy spaces, anticipating that they may offer a novel way of regularizing spacetime dynamics. We obtain actions for gravity on fuzzy S2 and on fuzzy CP3 in terms of finite dimensional matrices. Application to M(atrix) theory is also discussed. With an introduction of extra potentials to the theory, we show that it also has new brane solutions whose transverse directions are described by fuzzy S 4 and fuzzy CP3. The extra potentials can be considered as fuzzy versions of differential forms or fluxes, which enable us to discuss compactification models of M(atrix) theory. In particular, compactification down to fuzzy S4 is discussed and a realistic matrix model of M-theory in four-dimensions is proposed.
Gauge/gravity duality applied to condensed matter systems
Energy Technology Data Exchange (ETDEWEB)
Ammon, Martin Matthias
2010-07-07
developed. Finally a second model for the field theory at the quantum-critical point, a Chern-Simons matter theory in (2+1) dimensions is studied more precisely. On the gravitational side thereby higher-dimensional membranes and other non-perturbative objects, so-called KK-monopoles are embedded in M-theory respectively its type IIA limit.
Topics in elementary particle physics
Jin, Xiang
The author of this thesis discusses two topics in elementary particle physics: n-ary algebras and their applications to M-theory (Part I), and functional evolution and Renormalization Group flows (Part II). In part I, Lie algebra is extended to four different n-ary algebraic structure: generalized Lie algebra, Filippov algebra, Nambu algebra and Nambu-Poisson tensor; though there are still many other n-ary algebras. A natural property of Generalized Lie algebras — the Bremner identity, is studied, and proved with a totally different method from its original version. We extend Bremner identity to n-bracket cases, where n is an arbitrary odd integer. Filippov algebras do not focus on associativity, and are defined by the Fundamental identity. We add associativity to Filippov algebras, and give examples of how to construct Filippov algebras from su(2), bosonic oscillator, Virasoro algebra. We try to include fermionic charges into the ternary Virasoro-Witt algebra, but the attempt fails because fermionic charges keep generating new charges that make the algebra not closed. We also study the Bremner identity restriction on Nambu algebras and Nambu-Poisson tensors. So far, the only example 3-algebra being used in physics is the BLG model with 3-algebra A4, describing two M2-branes interactions. Its extension with Nambu algebra, BLG-NB model, is believed to describe infinite M2-branes condensation. Also, there is another propose for M2-brane interactions, the ABJM model, which is constructed by ordinary Lie algebra. We compare the symmetry properties between them, and discuss the possible approaches to include these three models into a grand unification theory. In Part II, we give an approximate solution for Schroeder's equations, based on series and conjugation methods. We use the logistic map as an example, and demonstrate that this approximate solution converges to known analytical solutions around the fixed point, around which the approximate solution is constructed
REPORT OF RESEARCH ACCOMPLISHMENTS AND FUTURE GOALS HIGH ENERGY PHYSICS
Energy Technology Data Exchange (ETDEWEB)
Wise, Mark B. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Kapustin, Anton N. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Schwarz, John Henry [California Inst. of Technology (CalTech), Pasadena, CA (United States); Carroll, Sean [California Inst. of Technology (CalTech), Pasadena, CA (United States); Ooguri, Hirosi [California Inst. of Technology (CalTech), Pasadena, CA (United States); Gukov, Sergei [California Inst. of Technology (CalTech), Pasadena, CA (United States); Preskill, John [California Inst. of Technology (CalTech), Pasadena, CA (United States); Hitlin, David G. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Porter, Frank C. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Patterson, Ryan B. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Newman, Harvey B. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Spiropulu, Maria [California Inst. of Technology (CalTech), Pasadena, CA (United States); Golwala, Sunil [California Inst. of Technology (CalTech), Pasadena, CA (United States); Zhu, Ren-Yuan [California Inst. of Technology (CalTech), Pasadena, CA (United States)
2014-08-26
effort. Areas of activity include: CDMS II data analysis, contributions to SuperCDMS Soudan operations and analysis, R&D towards SuperCDMS SNOLAB, development of a novel screener for radiocontamination (the BetaCage), and development of new WIMP detector concepts. Ren-Yuan Zhu leads the HEP crystal laboratory for the advanced detector R&D effort. The crystal lab is involved in development of novel scintillating crystals and has proposed several crystal based detector concepts for future HEP experiments at the energy and intensity frontiers. Its current research effort is concentrated on development of fast crystal scintillators with good radiation hardness and low cost. II) THEORETICAL PHYSICS The main theme of Sergei Gukov's current research is the relation between the geometry of quantum group invariants and their categorification, on the one hand, and the physics of supersymmetric gauge theory and string theory, on the other. Anton Kapustin's research spans a variety of topics in non-perturbative Quantum Field Theory (QFT). His main areas of interest are supersymmetric gauge theories, non-perturbative dualities in QFT, disorder operators, Topological Quantum Field Theory, and non-relativistic QFT. He is also interested in the foundations and possible generalizations of Quantum Mechanics. Hirosi Ooguri's current research has two main components. One is to find exact results in Calabi-Yau compactification of string theory. Another is to explore applications of the AdS/CFT correspondence. He also plans to continue his project with Caltech postdoctoral fellows on BPS spectra of supersymmetric gauge theories in diverse dimensions. John Preskill works on quantum information science. This field may lead to important future technologies, and also lead to new understanding of issues in fundamental physics John Schwarz has been exploring a number of topics in superstring theory/M-theory, supersymmetric gauge theory, and their AdS/CFT relationships. Much of the
Calculating corrections in F-theory from refined BPS invariants and backreacted geometries
Energy Technology Data Exchange (ETDEWEB)
Poretschkin, Maximilian
2015-07-01
This thesis presents various corrections to F-theory compactifications which rely on the computation of refined Bogomol'nyi-Prasad-Sommerfield (BPS) invariants and the analysis of backreacted geometries. Detailed information about rigid supersymmetric theories in five dimensions is contained in an index counting refined BPS invariants. These BPS states fall into representations of SU(2){sub L} x SU(2){sub R}, the little group in five dimensions, which has an induced action on the cohomology of the moduli space of stable pairs. In the first part of this thesis, we present the computation of refined BPS state multiplicities associated to M-theory compactifications on local Calabi-Yau manifolds whose base is given by a del Pezzo or half K3 surface. For geometries with a toric realization we use an algorithm which is based on the Weierstrass normal form of the mirror geometry. In addition we use the refined holomorphic anomaly equation and the gap condition at the conifold locus in the moduli space in order to perform the direct integration and to fix the holomorphic ambiguity. In a second approach, we use the refined Goettsche formula and the refined modular anomaly equation that govern the (refined) genus expansion of the free energy of the half K3 surface. By this procedure, we compute the refined BPS invariants of the half K3 from which the results of the remaining del Pezzo surfaces are obtained by flop transitions and blow-downs. These calculations also make use of the high symmetry of the del Pezzo surfaces whose homology lattice contains the root lattice of exceptional Lie algebras. In cases where both approaches are applicable, we successfully check the compatibility of these two methods. In the second part of this thesis, we apply the results obtained from the calculation of the refined invariants of the del Pezzo respectively the half K3 surfaces to count non-perturbative objects in F-theory. The first application is given by BPS states of the E
BPS state counting using wall-crossing, holomorphic anomalies and modularity
International Nuclear Information System (INIS)
Wotschke, Thomas
2013-05-01
In this thesis we examine the counting of BPS states using wall-crossing, holomorphic anomalies and modularity. We count BPS states that arise in two setups: multiple M5-branes wrapping P x T 2 , where P denotes a divisor inside a Calabi-Yau threefold and topological string theory on elliptic Calabi-Yau threefolds. The first setup has a dual description as type IIA string theory via a D4-D2-D0 brane system. Furthermore it leads to two descriptions depending on the size of P and T 2 relative to each other. For the case of a small divisor P this setup is described by the (0,4) Maldacena-Strominger-Witten conformal field theory of a black hole in M-theory and for the case of small T 2 the setup can by described by N=4 topological Yang-Mills theory on P. The BPS states are counted by the modified elliptic genus, which can be decomposed into a vector-valued modular form that provides the generating function for the BPS invariants and a Siegel-Narain theta function. In the first part we discuss the holomorphic anomaly of the modified elliptic genus for the case of two M5-branes and divisors with b + 2 (P)=1. Due to the wall-crossing effect the change in the generating function is captured by an indefinite theta function, which is a mock modular form. We use the Kontsevich-Soibelman wall-crossing formula to determine the jumps in the modified elliptic genus. Using the regularisation procedure for mock modular forms of Zwegers, modularity can be restored at the cost of holomorphicity. We show that the non-holomorphic completion is due to bound states of single M5-branes. At the attractor point in the moduli space we prove the holomorphic anomaly equation, which is compatible with the holomorphic anomaly equations observed in the context of N=4 Yang-Mills theory on P 2 and E-strings on a del Pezzo surface. We calculate the generating functions of BPS invariants for the divisors P 2 , F 0 , F 1 and the del Pezzo surface dP 8 and dP 9 ((1)/(2) K3). In the second part we study
Abelian gauge symmetries in F-theory and dual theories
Song, Peng
In this dissertation, we focus on important physical and mathematical aspects, especially abelian gauge symmetries, of F-theory compactifications and its dual formulations within type IIB and heterotic string theory. F-theory is a non-perturbative formulation of type IIB string theory which enjoys important dualities with other string theories such as M-theory and E8 x E8 heterotic string theory. One of the main strengths of F-theory is its geometrization of many physical problems in the dual string theories. In particular, its study requires a lot of mathematical tools such as advanced techniques in algebraic geometry. Thus, it has also received a lot of interests among mathematicians, and is a vivid area of research within both the physics and the mathematics community. Although F-theory has been a long-standing theory, abelian gauge symmetry in Ftheory has been rarely studied, until recently. Within the mathematics community, in 2009, Grassi and Perduca first discovered the possibility of constructing elliptically fibered varieties with non-trivial toric Mordell-Weil group. In the physics community, in 2012, Morrison and Park first made a major advancement by constructing general F-theory compactifications with U(1) abelian gauge symmetry. They found that in such cases, the elliptically-fibered Calabi-Yau manifold that F-theory needs to be compactified on has its fiber being a generic elliptic curve in the blow-up of the weighted projective space P(1;1;2) at one point. Subsequent developments have been made by Cvetic, Klevers and Piragua extended the works of Morrison and Park and constructed general F-theory compactifications with U(1) x U(1) abelian gauge symmetry. They found that in the U(1) x U(1) abelian gauge symmetry case, the elliptically-fibered Calabi-Yau manifold that F-theory needs to be compactified on has its fiber being a generic elliptic curve in the del Pezzo surface dP2. In chapter 2 of this dissertation, I bring this a step further by
BPS state counting using wall-crossing, holomorphic anomalies and modularity
Energy Technology Data Exchange (ETDEWEB)
Wotschke, Thomas
2013-05-15
In this thesis we examine the counting of BPS states using wall-crossing, holomorphic anomalies and modularity. We count BPS states that arise in two setups: multiple M5-branes wrapping P x T{sup 2}, where P denotes a divisor inside a Calabi-Yau threefold and topological string theory on elliptic Calabi-Yau threefolds. The first setup has a dual description as type IIA string theory via a D4-D2-D0 brane system. Furthermore it leads to two descriptions depending on the size of P and T{sup 2} relative to each other. For the case of a small divisor P this setup is described by the (0,4) Maldacena-Strominger-Witten conformal field theory of a black hole in M-theory and for the case of small T{sup 2} the setup can by described by N=4 topological Yang-Mills theory on P. The BPS states are counted by the modified elliptic genus, which can be decomposed into a vector-valued modular form that provides the generating function for the BPS invariants and a Siegel-Narain theta function. In the first part we discuss the holomorphic anomaly of the modified elliptic genus for the case of two M5-branes and divisors with b{sup +}{sub 2}(P)=1. Due to the wall-crossing effect the change in the generating function is captured by an indefinite theta function, which is a mock modular form. We use the Kontsevich-Soibelman wall-crossing formula to determine the jumps in the modified elliptic genus. Using the regularisation procedure for mock modular forms of Zwegers, modularity can be restored at the cost of holomorphicity. We show that the non-holomorphic completion is due to bound states of single M5-branes. At the attractor point in the moduli space we prove the holomorphic anomaly equation, which is compatible with the holomorphic anomaly equations observed in the context of N=4 Yang-Mills theory on P{sup 2} and E-strings on a del Pezzo surface. We calculate the generating functions of BPS invariants for the divisors P{sup 2}, F{sub 0}, F{sub 1} and the del Pezzo surface dP{sub 8} and
String Theory Methods for Condensed Matter Physics
Nastase, Horatiu
2017-09-01
Preface; Acknowledgments; Introduction; Part I. Condensed Matter Models and Problems: 1. Lightning review of statistical mechanics, thermodynamics, phases and phase transitions; 2. Magnetism in solids; 3. Electrons in solids: Fermi gas vs. Fermi liquid; 4. Bosonic quasi-particles: phonons and plasmons; 5. Spin-charge separation in 1+1 dimensional solids: spinons and holons; 6. The Ising model and the Heisenberg spin chain; 7. Spin chains and integrable systems; 8. The thermodynamic Bethe ansatz; 9. Conformal field theories and quantum phase transitions; 10. Classical vs. quantum Hall effect; 11. Superconductivity: Landau-Ginzburg, London and BCS; 12. Topology and statistics: Berry and Chern-Simons, anyons and nonabelions; 13. Insulators; 14. The Kondo effect and the Kondo problem; 15. Hydrodynamics and transport properties: from Boltzmann to Navier-Stokes; Part II. Elements of General Relativity and String Theory: 16. The Einstein equation and the Schwarzschild solution; 17. The Reissner-Nordstrom and Kerr-Newman solutions and thermodynamic properties of black holes; 18. Extra dimensions and Kaluza-Klein; 19. Electromagnetism and gravity in various dimensions. Consistent truncations; 20. Gravity plus matter: black holes and p-branes in various dimensions; 21. Weak/strong coupling dualities in 1+1, 2+1, 3+1 and d+1 dimensions; 22. The relativistic point particle and the relativistic string; 23. Lightcone strings and quantization; 24. D-branes and gauge fields; 25. Electromagnetic fields on D-branes. Supersymmetry and N = 4 SYM. T-duality of closed strings; 26. Dualities and M theory; 27. The AdS/CFT correspondence: definition and motivation; Part III. Applying String Theory to Condensed Matter Problems: 28. The pp wave correspondence: string Hamiltonian from N = 4 SYM; 29. Spin chains from N = 4 SYM; 30. The Bethe ansatz: Bethe strings from classical strings in AdS; 31. Integrability and AdS/CFT; 32. AdS/CFT phenomenology: Lifshitz, Galilean and Schrodinger
Michie, Susan; Wood, Caroline E; Johnston, Marie; Abraham, Charles; Francis, Jill J; Hardeman, Wendy
2015-11-01
Meeting global health challenges requires effective behaviour change interventions (BCIs). This depends on advancing the science of behaviour change which, in turn, depends on accurate intervention reporting. Current reporting often lacks detail, preventing accurate replication and implementation. Recent developments have specified intervention content into behaviour change techniques (BCTs) - the 'active ingredients', for example goal-setting, self-monitoring of behaviour. BCTs are 'the smallest components compatible with retaining the postulated active ingredients, i.e. the proposed mechanisms of change. They can be used alone or in combination with other BCTs' (Michie S, Johnston M. Theories and techniques of behaviour change: developing a cumulative science of behaviour change. Health Psychol Rev 2012;6:1-6). Domain-specific taxonomies of BCTs have been developed, for example healthy eating and physical activity, smoking cessation and alcohol consumption. We need to build on these to develop an internationally shared language for specifying and developing interventions. This technology can be used for synthesising evidence, implementing effective interventions and testing theory. It has enormous potential added value for science and global health. (1) To develop a method of specifying content of BCIs in terms of component BCTs; (2) to lay a foundation for a comprehensive methodology applicable to different types of complex interventions; (3) to develop resources to support application of the taxonomy; and (4) to achieve multidisciplinary and international acceptance for future development. Four hundred participants (systematic reviewers, researchers, practitioners, policy-makers) from 12 countries engaged in investigating, designing and/or delivering BCIs. Development of the taxonomy involved a Delphi procedure, an iterative process of revisions and consultation with 41 international experts; hierarchical structure of the list was developed using inductive
Sepehri, Alireza
2016-07-01
Recently, some authors (Cruz and Rojas, 2013 [1]) have constructed a Born-Infeld type action which may be written in terms of the Lovelock brane Lagrangians for a given dimension p. We reconsider their model in M-theory and study the process of birth and growth of nonlinear spinor and bosonic gravity during the construction of Mp-branes. Then, by application of this idea to BIonic system, we construct a BIonic superconductor in the background of nonlinear gravity. In this model, first, M0-branes link to each other and build an M5-brane and an anti-M5-brane connected by an M2-brane. M0-branes are zero dimensional objects that only scalars are attached to them. By constructing higher dimensional branes from M0-branes, gauge fields are produced. Also, if M0-branes don't link to each other completely, the symmetry of system is broken and fermions are created. The curvature produced by fermions has the opposite sign the curvature produced by gauge fields. Fermions on M5-branes and M2 plays the role of bridge between them. By passing time, M2 dissolves in M5's and nonlinear bosonic and spinor gravities are produced. By closing M5-branes towards each other, coupling of two identical fermions on two branes to each other causes that the square mass of their system becomes negative and some tachyonic states are created. For removing these tachyons, M5-branes compact, the sign of gravity between branes reverses, anti-gravity is produced which causes that branes and identical fermions get away from each other. This is the reason for the emergence of Pauli exclusion principle in Bionic system. Also, the spinor gravity vanishes and its energy builds a new M2 between M5-branes. We obtain the resistivity in this system and find that its value decreases by closing M5 branes to each other and shrinks to zero at colliding point of branes. This idea has different applications. For example, in cosmology, universes are located on M5-branes and M2-brane has the role of bridge between
Strings draw theorists together
Energy Technology Data Exchange (ETDEWEB)
Green, Michael [Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge (United Kingdom)
2000-03-01
string theorists over the past decade. Much has been learned about the non-perturbative extension of string theory now known as ''M theory'' and this has shed light on many previously mysterious aspects of quantum field theory. The range of new and potentially important developments is indeed impressive. One example is the accumulation of results on the role of ''noncommutative geometry'' in string theory. Another major theme of the meeting was the new ideas on how string theory may describe observed physics, such as the forces and particles in nature and their properties. The recent work by Lisa Randall of Princeton University and Raman Sundrum of Boston University is a variant of the ''brane world'' idea that has come to the fore over the past couple of years. According to this idea, which was reviewed by Randall at the conference, our four-dimensional universe can be thought of as a membrane (known as a three-brane) that is embedded inside a higher-dimensional universe. The number of higher dimensions is predicted by the structure of string theory. The possible consequences of this are striking. For example, in such a universe the fundamental energy scale of the theory may be much smaller than the Planck energy of 10{sup 19} GeV. Indeed, the scale could be so small that it will be accessible to direct experimental observation using the next generation of accelerators, such as the Large Hadron Collider that is currently under construction at CERN. This theme was further developed by Steven Hawking, who conjectured on how such a universe might have evolved from the initial quantum state that preceded the big bang. One of the most exciting developments over the past few years has been in understanding how so-called Yang-Mills gauge theories - the bread and butter of the Standard Model of particle physics - are related to quantum gravity by string theory. Particularly important is the so-called &apos
BOOK REVIEW: Universe or Multiverse?
Trimble, Virginia
2008-11-01
nature and other physical differences, which cannot communicate with ours even in principle. Such ensembles are predicted by some versions of inflation, string and M-theory. The anthropic principle is the idea that our universe has (or even must have) the structure, physics, chemistry and all required for me to be writing this and you to be reading it (editors are optional). Both concepts have firm supporters and firm opponents among the 26 male and one female authors. The woman, M-theorist Renata Kallosh, is for, and provides hints of how one might calculate, at least, the likelihood of our universe within an ensemble (a sort of testability). Her chapter is fairly heavy going in isolation, and readers who don't normally think about antisymmetric tensor gauge fields might want to start with John Donaghue, who explains what a particle physicist means by 'naturalness' and suggests that the known spectrum of quark and lepton masses might be a signature of multiverse origins. Given the Templeton sponsorship, you might reasonably want to know the extent to which 'progress in spirituality' has conditioned the topics covered. The answer is 'somewhat', in that authors range from the avowedly atheist (Stephen Hawking) to evangelical Christian quantum cosmologist Don Page, with stop-overs among the Jesuits (William Stoeger), philosophers of religion (Robin Collins), and the (I think) teleologists Paul Davies and John Barrow. There is also among the authors strong divergence of opinion on whether Hugh Everett's version of many worlds is (just) a quantum multiverse (Tegmark), almost certainly correct and meaningful (Page), or almost certainly wrong or meaningless (Carter). And two chapters, by Smolin and Weinberg, suggest that even the classic fine-tuning required for carbon to be formed from three helium nuclei may not be anthropically essential for a habitable universe. The last word belongs to Steven Weinberg. On previous occasions, Martin Rees has said that he has enough
Strings draw theorists together
International Nuclear Information System (INIS)
Green, Michael
2000-01-01
has been learned about the non-perturbative extension of string theory now known as ''M theory'' and this has shed light on many previously mysterious aspects of quantum field theory. The range of new and potentially important developments is indeed impressive. One example is the accumulation of results on the role of ''noncommutative geometry'' in string theory. Another major theme of the meeting was the new ideas on how string theory may describe observed physics, such as the forces and particles in nature and their properties. The recent work by Lisa Randall of Princeton University and Raman Sundrum of Boston University is a variant of the ''brane world'' idea that has come to the fore over the past couple of years. According to this idea, which was reviewed by Randall at the conference, our four-dimensional universe can be thought of as a membrane (known as a three-brane) that is embedded inside a higher-dimensional universe. The number of higher dimensions is predicted by the structure of string theory. The possible consequences of this are striking. For example, in such a universe the fundamental energy scale of the theory may be much smaller than the Planck energy of 10 19 GeV. Indeed, the scale could be so small that it will be accessible to direct experimental observation using the next generation of accelerators, such as the Large Hadron Collider that is currently under construction at CERN. This theme was further developed by Steven Hawking, who conjectured on how such a universe might have evolved from the initial quantum state that preceded the big bang. One of the most exciting developments over the past few years has been in understanding how so-called Yang-Mills gauge theories - the bread and butter of the Standard Model of particle physics - are related to quantum gravity by string theory. Particularly important is the so-called ''Maldacena correspondence'', first developed by Juan Maldacena of Harvard University. This correspondence gives an explicit
Geometry and physics of branes
International Nuclear Information System (INIS)
Gal'tsov, D V
2003-01-01
deformation theory of holomorphic structures on vector bundles, which is a direct analogue of Kodaira and Spencer's study of the deformation of the complex structure of the complex manifold itself. Then it is explained how the homological algebra of A ∞ or L ∞ algebras can be applied to the problem of moduli, and the theorem is sketched stating that the gauge equivalence class of solutions of the Maurer-Cartan equation is invariant with respect to the homotopy types of these algebras. This discussion is then applied to the homological mirror symmetry, introducing the universal Novikov ring and Floer homology. The last series of lectures is devoted to the so-called geometric conifold transition related to the Gopakumar-Vafa conjecture that the SU(N) Chern-Simons theory on S 3 is dual to IIA string theory (with fluxes) compactified on a certain Calabi-Yau manifold. The geometry of the conifold transition involved in this discussion is described in detail, including physical applications. Some background endcolumn on Chern-Simons theory is presented and spaces with G 2 holonomies are discussed. M-theory treatment of the above correspondence is also given. Useful mathematical definitions are collected in five appendices. The book is certainly very useful both as an introduction to the modern topics of superstring theory and as a rather deep exposition of some advanced mathematical tools involved in it. (book review. Edited by U Bruzzo, V Gorini and U Moschella ISBN: 0-750-30863-X )
Energy Technology Data Exchange (ETDEWEB)
Carlip, S [Department of Physics, University of California, Davis, CA 95616 (United States)
2006-10-21
, it could easily be missed-but these are minor drawbacks. Readers will find clear answers to many 'frequently asked questions.' Are D-branes really necessary? Polchinski begins with T-duality for the closed string, and shows that the extension to open strings requires the existence of D-branes. How does string theory incorporate gravity? The two standard answers are that string theory contains a massless spin two 'graviton' and that consistent string propagation in a curved background requires that the background metric satisfy the Einstein field equations; Polchinski links the two, showing that the background metric can be viewed as a coherent state of the spin two excitations. Volume II, Superstring Theory and Beyond, extends Volume I to superstring theory, and then proceeds to treat a range of more advanced subjects: effective actions for branes, dualities and equivalences among string theories, M theory, stringy black holes, compactifications and four-dimensional field theories, and the like. The tone of this volume changes a bit-it is not as self-contained, and reads less like a textbook and more like an extended review article. I suspect, for example, that few students without a strong background in field theory will follow the discussion of anomalies in chapter 12. The change can be largely attributed to the content: the superstring is inherently more difficult than the bosonic string, and the newer material is not as deeply understood. But there are a few weaknesses in presentation as well: for instance, a discussion in chapter 11 of the relationship between symmetries and constraints omits any explanation of how one decides whether a transformation generates a symmetry or a constraint. Any two-volume book on string theory is necessarily incomplete. In his introduction, Polchinski cites the lack of a more thorough treatment of compactifications on curved manifolds. I would personally have liked to see more about noncritical strings and
Pati, Jogesh C.
2017-03-01
the next-generation large underground detectors — like DUNE and HyperKamiokande — coupled to long-baseline neutrino beams to search simultaneously with high sensitivity for (a) proton decay, (b) neutrino oscillations and (c) supernova neutrinos. It is remarked that the potential for major discoveries through these searches would be high. Some concluding remarks on the invaluable roles of neutrinos and especially of proton decay in probing physics at the highest energy scales are made in the last section. The remarkable success of a class of supersymmetric grand unification models (discussed here) in explaining a large set of distinct phenomena is summarized. Noticing such a success and yet its limitations in addressing some fundamental issues within its premises, such as an understanding of the origin of the three families, and most importantly, the realization of a well-understood unified quantum theory of gravity describing reality, some wishes are expressed on the possible emergence and the desirable role of a string-derived grand-unified bridge between string/M-theory in higher dimensions and the world of phenomena at low energies.
Modern Canonical Quantum General Relativity;
International Nuclear Information System (INIS)
Kiefer, Claus
2008-01-01
The open problem of constructing a consistent and experimentally tested quantum theory of the gravitational field has its place at the heart of fundamental physics. The main approaches can be roughly divided into two classes: either one seeks a unified quantum framework of all interactions or one starts with a direct quantization of general relativity. In the first class, string theory (M-theory) is the only known example. In the second class, one can make an additional methodological distinction: while covariant approaches such as path-integral quantization use the four-dimensional metric as an essential ingredient of their formalism, canonical approaches start with a foliation of spacetime into spacelike hypersurfaces in order to arrive at a Hamiltonian formulation. The present book is devoted to one of the canonical approaches-loop quantum gravity. It is named modern canonical quantum general relativity by the author because it uses connections and holonomies as central variables, which are analogous to the variables used in Yang-Mills theories. In fact, the canonically conjugate variables are a holonomy of a connection and the flux of a non-Abelian electric field. This has to be contrasted with the older geometrodynamical approach in which the metric of three-dimensional space and the second fundamental form are the fundamental entities, an approach which is still actively being pursued. It is the author's ambition to present loop quantum gravity in a way in which every step is formulated in a mathematically rigorous form. The formal Leitmotiv of loop quantum gravity is background independence. Non-gravitational theories are usually quantized on a given non-dynamical background. In contrast, due to the geometrical nature of gravity, no such background exists in quantum gravity. Instead, the notion of a background is supposed to emerge a posteriori as an approximate notion from quantum states of geometry. As a consequence, the standard ultraviolet divergences of
International Nuclear Information System (INIS)
Carlip, S
2006-01-01
-but these are minor drawbacks. Readers will find clear answers to many 'frequently asked questions.' Are D-branes really necessary? Polchinski begins with T-duality for the closed string, and shows that the extension to open strings requires the existence of D-branes. How does string theory incorporate gravity? The two standard answers are that string theory contains a massless spin two 'graviton' and that consistent string propagation in a curved background requires that the background metric satisfy the Einstein field equations; Polchinski links the two, showing that the background metric can be viewed as a coherent state of the spin two excitations. Volume II, Superstring Theory and Beyond, extends Volume I to superstring theory, and then proceeds to treat a range of more advanced subjects: effective actions for branes, dualities and equivalences among string theories, M theory, stringy black holes, compactifications and four-dimensional field theories, and the like. The tone of this volume changes a bit-it is not as self-contained, and reads less like a textbook and more like an extended review article. I suspect, for example, that few students without a strong background in field theory will follow the discussion of anomalies in chapter 12. The change can be largely attributed to the content: the superstring is inherently more difficult than the bosonic string, and the newer material is not as deeply understood. But there are a few weaknesses in presentation as well: for instance, a discussion in chapter 11 of the relationship between symmetries and constraints omits any explanation of how one decides whether a transformation generates a symmetry or a constraint. Any two-volume book on string theory is necessarily incomplete. In his introduction, Polchinski cites the lack of a more thorough treatment of compactifications on curved manifolds. I would personally have liked to see more about noncritical strings and Liouville theory and about the Green-Schwarz superstring