Structure of gauge and gravitational anomalies*
International Nuclear Information System (INIS)
It is shown how the form of the gauge and gravitational anomalies in quantum field theories may be derived from classical index theorems. The gravitational anomaly in both Einstein and Lorentz form is considered and their equivalence is exhibited. The formalism of gauge and gravitational theories is reviewed using the language of differential geometry, and notions from the theory of characteristic classes necessary for understanding the classical index theorems are introduced. The treatment of known topological results includes a pedagogical derivation of the Wess-Zumino effective Lagrangian in abitrary even dimension. The relation between various forms of the anomaly present in the literature is also clarified
The structure of gauge and gravitational anomalies
International Nuclear Information System (INIS)
It is shown how the form of the gauge and gravitational anomalies in quantum field theories may be derived from classical index theorems. The gravitational anomaly in both Einstein and Lorentz form is considered and their equivalence is exhibited. The formalism of gauge and gravitational theories is reviewed using the language of differential geometry, and notions from the theory of characteristic classes necessary for understanding the classical index theorems are introduced. The treatment of known topological results includes a pedagogical derivation of the Wess-Zumino effective Lagrangian in arbitrary even dimension. The relation between various forms of the anomaly present in the literature is also clarified
Gauge and gravitational anomalies in D=4 N=1 orientifolds
Scrucca, C. A.; Serone, M.
1999-01-01
We analyze in detail the cancellation of U(1)-gauge and U(1)-gravitational anomalies in certain D=4 N=1 Type IIB orientifolds, from a string theory point of view. We verify the proposal that these anomalies are cancelled by a Green-Schwarz mechanism involving only twisted RR fields. By factorizing one-loop partition functions, we also get the RR couplings of D-branes and O-planes to theses fields. Twisted sectors with fixed planes participate to the inflow mechanism in a peculiar way.SR416082...
Gauge and gravitational anomalies in D=4 N=1 orientifolds
Scrucca, Claudio A; Scrucca, Claudio A.; Serone, Marco
1999-01-01
The cancellation of U(1)-gauge and U(1)-gravitational anomalies in certain D=4 N=1 Type IIB orientifolds is analyzed in detail, from a string theory point of view. We verify the proposal that these anomalies are cancelled by a Green-Schwarz mechanism involving only twisted Ramond-Ramond fields. By factorizing one-loop partition functions, we also get the anomalous couplings of D-branes, O-planes and orbifold fixed-points to these twisted fields. Twisted sectors with fixed-planes participate to the inflow mechanism in a peculiar way.
Gauge and Gravitational Anomalies and Hawking Radiation of Rotating BTZ Black Holes
Setare, M. R.
2006-01-01
In this paper we obtain the flux of Hawking radiation from Rotating BTZ black holes from gauge and gravitational anomalies point of view. Then we show that the gauge and gravitational anomaly in the BTZ spacetime is cancelled by the total flux of a 2-dimensional blackbody at the Hawking temperature of the spacetime.
Energy Technology Data Exchange (ETDEWEB)
Banerjee, Rabin, E-mail: rabin@bose.res.in; Dey, Shirsendu, E-mail: shirsendu12@bose.res.in
2014-06-02
We obtain the constitutive relations for the stress tensor and gauge current in (1+1)-dimensional hydrodynamics in the presence of both gauge and gravitational (conformal as well as diffeomorphism) anomalies. The relations between response parameters and anomaly coefficients are also found. The role of the Israel Hartle Hawking vacuum is emphasised. Finally, in the absence of gauge fields, earlier results obtained by a hydrodynamic expansion are reproduced.
Classical gauge gravitation theory
G. Sardanashvily
2011-01-01
Classical gravitation theory is formulated as gauge theory on natural bundles where gauge symmetries are general covariant transformations and a gravitational field is a Higgs field responsible for their spontaneous symmetry breaking.
Bosonic chiral anomalies in gravitational field
International Nuclear Information System (INIS)
The notion of chirality for electromagneticting field is defined. The chirality is classically conserved in gravitational interaction. The corresponding chiral current is however anomalous in external gravitational field. This anomaly is analogous to the well-known fermionic triangle anomaly. The result obtained permits to calculate radiative corrections to the fermionic chiral anomaly in gravitational field. The relation between the number of zero modes of antisymmetric tensor gauge field (with zero spin) and the anomaly for vector field is considered. The possible observational manifestations of the photonic chiral anomaly in the gravitational field of the kerr black hole are discussed
Gravitational Anomaly and Transport
Landsteiner, Karl; Pena-Benitez, Francisco
2011-01-01
Quantum anomalies give rise to new transport phenomena. In particular a magnetic field can induce an anomalous current via the chiral magnetic effect and a vortex in the relativistic fluid can also induce a current via the chiral vortical effect. The related transport coefficients can be calculated via Kubo formulas. We evaluate the Kubo formula for the anomalous vortical conductivity at weak coupling and show that it receives contributions proportional to the gravitational anomaly coefficient. The gravitational anomaly gives rise to an anomalous vortical effect even for an uncharged fluid.
International Nuclear Information System (INIS)
The suggested theory involves a drastic revision of the role of local internal symmetries in the physical concept of curved geometry. Under the reflection of fields and their dynamics from Minkowski to Riemannian space a standard gauge principle of local internal symmetries has been generalized. A gravitation gauge group is proposed, which is generated by hidden local internal symmetries. In all circumstances, it seemed to be of the greatest importance for the understanding of the physical nature of gravity. The most promising aspect in their approach so far is the fact that the energy-momentum conservation laws of gravitational interacting fields are formulated quite naturally by exploiting all the advantages of auxiliary shadow fields on flat shadow space. The mechanism developed here enables one to infer Einstein's equation of gravitation, but only with a strong difference from Einstein's theory at the vital point of well-defined energy-momentum tensor of gravitational field and conservation laws. The gravitational interaction as well as the general distortion of the manifold G(2.2.3) with hidden group Uloc (1) has been considered
Gravitational Anomaly and Hydrodynamics
Landsteiner, Karl; Melgar, Luis; Pena-Benitez, Francisco
2011-01-01
We study the anomalous induced current of a vortex in a relativistic fluid via the chiral vortical effect, which is analogous to the anomalous current induced by a magnetic field via the chiral magnetic effect. We perform this analysis at weak and strong coupling. We discuss inequivalent implementations to the chemical potential for an anomalous symmetry. At strong coupling we use a holographic model with a pure gauge and mixed gauge-gravitational Chern-Simons term in the action. We discuss the holographic renormalization and show that the Chern-Simons terms do not induce new divergences. Strong and weak coupling results agree precisely. We also point out that the holographic calculation can be done without a singular gauge field configuration on the horizon of the black hole.
Gravitational Anomaly and Hydrodynamics
International Nuclear Information System (INIS)
We study the anomalous induced current of a vortex in a relativistic fluid via the chiral vortical effect, which is analogous to the anomalous current induced by a magnetic field via the chiral magnetic effect. We perform this analysis at weak and strong coupling. We discuss inequivalent implementations to the chemical potential for an anomalous symmetry. At strong coupling we use a holographic model with a pure gauge and mixed gauge-gravitational Chern-Simons term in the action. We discuss the holographic renormalization and show that the Chern-Simons terms do not induce new divergences. Strong and weak coupling results agree precisely. We also point out that the holographic calculation can be done without a singular gauge field configuration on the horizon of the black hole.
Fluid/Gravity Correspondence, Second Order Transport and Gravitational Anomaly*,**
Directory of Open Access Journals (Sweden)
Megías Eugenio
2014-03-01
Full Text Available We study the transport properties of a relativistic fluid affected by chiral and gauge-gravitational anomalies. The computation is performed in the framework of the fluid/gravity correspondence for a 5 dim holographic model with Chern-Simons terms in the action. We find new anomalous and non anomalous transport coefficients, as well as new contributions to the existing ones coming from the mixed gauge-gravitational anomaly. Consequences for the shear waves dispersion relation are analyzed.
Gravitation and Gauge Symmetries
International Nuclear Information System (INIS)
The purpose of this book (I quote verbatim from the back cover) is to 'shed light upon the intrinsic structure of gravity and the principle of gauge invariance, which may lead to a consistent unified field theory', a very laudable aim. The content divides fairly clearly into four sections (and origins). After a brief introduction, chapters 2-6 review the 'Structure of gravity as a theory based on spacetime gauge symmetries'. This is fairly straightforward material, apparently based on a one-semester graduate course taught at the University of Belgrade for about two decades, and, by implication, this is a reasonably accurate description of its level and assumed knowledge. There follow two chapters of new material entitled 'Gravity in flat spacetime' and 'Nonlinear effects in gravity'. The final three chapters, entitled 'Supersymmetry and supergravity', 'Kaluza-Klein theory' and 'String theory' have been used for the basis of a one-semester graduate course on the unification of fundamental interactions. The book concludes with thirteen appendices, covering mainly technical issues but also including Ashtekhar variables and Chern-Simons theory. Irritatingly, there is a separate bibliography for each chapter (which leads to much duplication) but commendably, the author highlights selected sources for suitable further reading. Also to be welcomed wholeheartedly are well-chosen worked examples and exercises, ranging from easy to fairly challenging, in each chapter. This is a properly bound paperback, hardly inexpensive, but well up to IOP's impeccable production standards. Could this be the ideal textbook for a research student or even an established researcher from another field to pick up the latest developments in field theory? Unfortunately this is not the whole story. The back cover also asserts, while talking about gauge invariance, that 'It is less known that the principle of equivalence, one of the basic dynamical properties of the gravitational interaction, can be expressed as a (spacetime) gauge symmetry'. On page 10 this is qualified to be a local symmetry. On pages 62-3 this hidden result is revealed. As every relativist knows, the principle of equivalence implies that for each spacetime point p a chart (normal coordinates at p) can be chosen so that the metric tensor takes its Minkowski value and its (partial) derivatives vanish at p. In other words every (pseudo-)Riemannian manifold is locally flat, the 'less known' result. So what else can the author tell us about gravity? There is little to fault in the first two sections of the book, trying to express gravity as a nonlinear spin-2 theory on Minkowski spacetime, apart from the obvious objection. A well-known and highly-recommendable textbook by S Weinberg 1972 Gravitation and Cosmology (New York: Wiley), carries out, at a more elementary level, a similar programme with the same defect. Such local theories cannot predict global changes whereby spacetime has a different topology to the Minkowski one. (The unconvinced reader should investigate references to black holes in Weinberg's text.) As speaker after speaker at the S W Hawking 60th Birthday Conference last week emphasized, when trying to unify gravity with quantum theory, it is perilous to neglect geometry. Because the later chapters on supersymmetry, supergravity, Kaluza-Klein and string theories are more fashionable, I need to point out an important caveat. Excluding textbooks and conference volumes, all (English language) citations in the supersymmetry/supergravity chapter are at least 16 years old. Apart from one 2000 article (on teleparallel theory) this age gap drops by three years for the chapter on Kaluza-Klein theory, and it does not change any further for the string theory chapter. There have been more recent significant advances in our understanding and interpretation of these theories but, alas, they are not chronicled here. I raised a question as to the value of this book at the end of the first paragraph, and I want to answer it within the context of the conference mentioned above, which tried t
Gravitational Anomaly and Transport Phenomena
International Nuclear Information System (INIS)
Quantum anomalies give rise to new transport phenomena. In particular, a magnetic field can induce an anomalous current via the chiral magnetic effect and a vortex in the relativistic fluid can also induce a current via the chiral vortical effect. The related transport coefficients can be calculated via Kubo formulas. We evaluate the Kubo formula for the anomalous vortical conductivity at weak coupling and show that it receives contributions proportional to the gravitational anomaly coefficient. The gravitational anomaly gives rise to an anomalous vortical effect even for an uncharged fluid.
Holographic Gravitational Anomaly and Chiral Vortical Effect
Landsteiner, Karl; Melgar, Luis; Pena-Benitez, Francisco
2011-01-01
We analyze a holographic model with a pure gauge and a mixed gauge-gravitational Chern-Simons term in the action. These are the holographic implementations of the usual chiral and the mixed gauge-gravitational anomalies in four dimensional field theories with chiral fermions. We discuss the holographic renormalization and show that the gauge-gravitational Chern-Simons term does not induce new divergences. In order to cancel contributions from the extrinsic curvature at a boundary at finite distance a new type of counterterm has to be added however. This counterterm can also serve to make the Dirichlet problem well defined in case the gauge field strength vanishes on the boundary. A charged asymptotically AdS black hole is a solution to the theory and as an application we compute the chiral magnetic and chiral vortical conductivities via Kubo formulas. We find that the characteristic term proportional to T^2 is present also at strong coupling and that its numerical value is not renormalized compared to the wea...
Holographic gravitational anomaly and chiral vortical effect
Landsteiner, Karl; Megías, Eugenio; Melgar, Luis; Pena-Benitez, Francisco
2011-09-01
We analyze a holographic model with a pure gauge and a mixed gauge-gravitational Chern-Simons term in the action. These are the holographic implementations of the usual chiral and the mixed gauge-gravitational anomalies in four dimensional field theories with chiral fermions. We discuss the holographic renormalization and show that the gauge-gravitational Chern-Simons term does not induce new divergences. In order to cancel contributions from the extrinsic curvature at a boundary at finite distance a new type of counterterm has to be added however. This counterterm can also serve to make the Dirichlet problem well defined in case the gauge field strength vanishes on the boundary. A charged asymptotically AdS black hole is a solution to the theory and as an application we compute the chiral magnetic and chiral vortical conductivities via Kubo formulas. We find that the characteristic term proportional to T 2 is present also at strong coupling and that its numerical value is not renormalized compared to the weak coupling result.
International Nuclear Information System (INIS)
It is often the case that naive introduction of the messenger sector to supersymmetry breaking models causes the supersymmetry restoration. We discuss a possibility of stabilizing the supersymmetry broken vacuum by the gravitational interaction
Gravitation and Gauge Symmetries
Stewart, J
2002-01-01
The purpose of this book (I quote verbatim from the back cover) is to 'shed light upon the intrinsic structure of gravity and the principle of gauge invariance, which may lead to a consistent unified field theory', a very laudable aim. The content divides fairly clearly into four sections (and origins). After a brief introduction, chapters 2-6 review the 'Structure of gravity as a theory based on spacetime gauge symmetries'. This is fairly straightforward material, apparently based on a one-semester graduate course taught at the University of Belgrade for about two decades, and, by implication, this is a reasonably accurate description of its level and assumed knowledge. There follow two chapters of new material entitled 'Gravity in flat spacetime' and 'Nonlinear effects in gravity'. The final three chapters, entitled 'Supersymmetry and supergravity', 'Kaluza-Klein theory' and 'String theory' have been used for the basis of a one-semester graduate course on the unification of fundamental interactions. The boo...
Review on possible gravitational anomalies
Energy Technology Data Exchange (ETDEWEB)
Amador, Xavier E [Centro de Investigacion y Estudios Avanzados, CINVESTAV, Dept. of Physics, Av. IPN 2508, 07000 Ciudad de Mexico, D.F. (Mexico)
2005-01-15
This is an updated introductory review of 2 possible gravitational anomalies that has attracted part of the Scientific community: the Allais effect that occur during solar eclipses, and the Pioneer 10 spacecraft anomaly, experimented also by Pioneer 11 and Ulysses spacecrafts. It seems that, to date, no satisfactory conventional explanation exist to these phenomena, and this suggests that possible new physics will be needed to account for them. The main purpose of this review is to announce 3 other new measurements that will be carried on during the 2005 solar eclipses in Panama and Colombia (Apr. 8) and in Portugal (Oct.15)
International Nuclear Information System (INIS)
We present gauge theories of gravitation based, respectively, on the general linear group GL(n, R) and its inhomogeneous extension IGL(n, R). [SO(n-1,1) and ISO(n-1,1) for torsion-free manifolds]. Noting that the geometry of the conventional gauge theories can be described in terms of a principal fiber bundle, and that their action is a scalar in such a superspace, we construct principal fiber bundles based on the above gauge groups and propose to describe gravitation in terms of their corresponding scalar curvatures. To ensure that these manifolds do indeed have close ties with the space-time of general relativity, we make use of the notion of the parallel transport of vector fields in space-time to uniquely relate the connections in space-time to the gauge potentials in fiber bundles. The relations turn out to be similar to that suggested earlier by Yang. The actions we obtain are related to those of Einstein and Yang but are distinct from both and have an Einstein limit. The inclusion of internal symmetry leads to the analogs of Einstein-Yang-Mills equations. A number of variations and less attractive alternatives based on the subgroups of the above groups are also discussed
Gravitation and gauge theory of dislocations
International Nuclear Information System (INIS)
Question concerning the physical meaning of translation group gauge fields is interpreted proceding from gauge dislocation theory. Analysis using foliated space formalism has shown that gravitational field cannot be identified with translation group gauge field and efforts to present gravitation as space-time deformation are not correct
Unification of Gravitation and Gauge Fields
Huang, Xin-Bing
2004-01-01
In this letter, I indicate that complex daor field should also have spinor suffixes. The gravitation and gauge fields are unified under the framework of daor field. I acquire the elegant coupling equation of gravitation and gauge fields, from which Einstein's gravitational equation can be deduced.
Anomaly cancellation condition in lattice gauge theory
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We show that, to all orders of powers of the gauge potential, a gauge anomaly ? defined on 4-dimensional infinite lattice can always be removed by a local counterterm, provided that ? depends smoothly and locally on the gauge potential and that ? reproduces the gauge anomaly in the continuum theory in the classical continuum limit: The unique exception is proportional to the anomaly in the continuum theory. This follows from an analysis of nontrivial local solutions to the Wess-Zumino consistency condition in lattice gauge theory. Our result is applicable to the lattice chiral gauge theory based on the Ginsparg-Wilson Dirac operator, when the gauge field is sufficiently weak parallel-U(n,?) - 1-parallel < ?', where U(n,?) is the link variable and ?' a certain small positive constant. (author)
Gauge invariant gravitation theory. 1. Gravitational field source and spin
International Nuclear Information System (INIS)
It is shown that gauge invariance occurs as the consequence of physical field (fields with certain spin) description by the values, transformed as irreducible representations of homogeneous Lorentz group. Gauge-invariant lagrangian of the field of 2 spin was constructed. It was proved that gravitational field represented the superposition of gauge-invariant fields of 2 and 0 spins. Occurrence of the zero spin field is directly related with nonpreservation of the (gauge-invariant) source of gravitational field
Gauge gravitation theory from the geometric viewpoint
G. Sardanashvily
2005-01-01
This is the Preface to the special issue of 'International Journal of Geometric Methods in Modern Physics', v.3, N.1 (2006) dedicated to the 50th aniversary of gauge gravitation theory. It addresses the geometry underlying gauge gravitation theories, their higher-dimensional, supergauge and non-commutatuve extensions.
Gravitation and the gauge theory of dislocations
International Nuclear Information System (INIS)
The gauge theory of gravitation has long been dominated by the model of a gravitational field as a gauge field of the translation group. However, a fiber bundle analysis showed that one cannot identify these two fields. This led to the question concerning the physical meaning of the gauge fields of the translation group. The answer to this question can be given from the point of view of the gauge theory of dislocations. The argument stresses the special character of the gauge field of the translation group, not related to the Einstein gravity, and the incorrectness of the wide-spread attempts to represent gravity as a kind of space-time deformation
Gravitational correction to running of gauge couplings.
Robinson, Sean P; Wilczek, Frank
2006-06-16
We calculate the contribution of graviton exchange to the running of gauge couplings at lowest non-trivial order in perturbation theory. Including this contribution in a theory that features coupling constant unification does not upset this unification, but rather shifts the unification scale. When extrapolated formally, the gravitational correction renders all gauge couplings asymptotically free. PMID:16803367
Gravitation as Gauge theory of Poincare Group
International Nuclear Information System (INIS)
The geometrical approach to gauge theories, based on fiber-bundles, is shown in detail. Several gauge formalisms for gravitation are examined. In particular, it is shown how to build gauge theories for non-semisimple groups. A gravitational theory for the Poincare group, with all the essential characteristics of a Yang-Mills theory is proposed. Inonu-Wigner contractions of gauge theories are introduced, which provide a Lagrangian formalism, equivalent to a Lagrangian de Sitter theory supplemented by weak constraints. Yang and Einstein theories for gravitation become particular cases of a Yang-Mills theory. The classical limit of the proposed formalism leads to the Poisson equation, for the static case. (Author)
Anomaly cancellation and abelian gauge symmetries in F-theory
Cveti?, Mirjam; Grimm, Thomas W.; Klevers, Denis
2013-02-01
We study 4D F-theory compactifications on singular Calabi-Yau fourfolds with fluxes. The resulting {N}=1 effective theories can admit non-Abelian and U(1) gauge groups as well as charged chiral matter. In these setups we analyze anomaly cancellation and the generalized Green-Schwarz mechanism. This requires the study of 3D {N}=2 theories obtained by a circle compactification and their M-theory duals. Reducing M- theory on resolved Calabi-Yau fourfolds corresponds to considering the effective theory on the 3D Coulomb branch in which certain massive states are integrated out. Both 4D gaugings and 3D one-loop corrections of these massive states induce Chern-Simons terms. All 4D anomalies are captured by the one-loop terms. The ones corresponding to the mixed gauge-gravitational anomalies depend on the Kaluza-Klein vector and are induced by integrating out Kaluza-Klein modes of the U(1) charged matter. In M-theory all Chern-Simons terms classically arise from G 4-flux. We find that F-theory fluxes implement automatically the 4D Green-Schwarz mechanism if non-trivial geometric relations for the resolved Calabi-Yau fourfold are satisfied. We confirm these relations in various explicit examples and elucidate the general construction of U(1) symmetries in F-theory. We also compare anomaly cancellation in F-theory with its analog in Type IIB orientifold setups.
Conformal Anomalies and the Gravitational Effective Action: The $TJJ$ Correlator for a Dirac Fermion
Armillis, R.; Coriano, C.; Rose, L. Delle
2009-01-01
We compute in linearized gravity all the contributions to the gravitational effective action due to a virtual Dirac fermion, related to the conformal anomaly. This requires, in perturbation theory, the identification of the gauge-gauge-graviton vertex off mass shell, involving the correlator of the energy-momentum tensor and two vector currents ($TJJ$), which is responsible for the generation of the gauge contributions to the conformal anomaly in gravity. We also present the...
Interpretation of Venus gravitational anomalies
International Nuclear Information System (INIS)
The Venus gravity field anomalies are interpreted from three harmonics of potential expansion. Masses and depths of the anomaly centers in three regions: the Aphrodita land, the Ishtar land and in the South of the planet, are defined from the Venus geoid height, pure anomaly of attractive force, and plumb deviation. These depths are determined to be 930-1140 km. Analogous Earth anomalies in the field smoothing from 16 to 3 harmonics are characterized by depth overestimation. 1.4-times. Because of this, depths of the Venus anomaly sources reduced to 16 harmonics lie approximately in the range of 700-800 km, that is they correspond to the depth of bedding of the Venus mantle second phase boundary
An introduction to gravitational anomalies
International Nuclear Information System (INIS)
The outline of these lectures is as follows: We will first analyze the abelian anomaly from the point of view of the Atiyah-Singer index theorem. This is clearly not the first time that this analysis has been carried out, but it will give us a chance of introducing a general method of computing anomalies based on supersymmetric quantum mechanics. Then we will present the general strategy for identifying and computing the anomalies in the energy-momentum tensor and what can be learned from them
Gauge Anomalies and Neutrino Seesaw Models
Neves Cebola, Luis Manuel
Despite the success of the Standard Model concerning theoretical predictions, there are several experimental results that cannot be explained and there are reasons to believe that there exists new physics beyond it. Neutrino oscillations, and hence their masses, are examples of this. Experimentally it is known that neutrinos masses are quite small, when compared to all Standard Model particle masses. Among the theoretical possibilities to explain these tiny masses, the seesaw mechanism is a simple and well-motivated framework. In its minimal version, heavy particles are introduced that decouple from the theory in the early universe. To build consistent theories, classical symmetries need to be preserved at quantum level, so that there are no anomalies. The cancellation of these anomalies leads to constraints in the parameters of the theory. One attractive solution is to realize the anomaly cancellation through the modication of the gauge symmetry. In this thesis we present a short review of some features of t...
On the Poincare Gauge Theory of Gravitation
Ali, S A; Cafaro, C.; Capozziello, S.; Corda, Ch.
2009-01-01
We present a compact, self-contained review of the conventional gauge theoretical approach to gravitation based on the local Poincare group of symmetry transformations. The covariant field equations, Bianchi identities and conservation laws for angular momentum and energy-momentum are obtained.
Gravitational rescue of minimal gauge mediation
Iyer, Abhishek M; Vempati, Sudhir K
2014-01-01
Gravity mediation supersymmetry breaking become comparable to gauge mediated supersymmetry breaking contributions when messenger masses are close to the GUT scale. By suitably tuning the gravity contributions one can then modify the soft supersymmetry breaking sector to generate a large stop mixing parameter and a light higgs mass of 125 GeV. In this kind of hybrid models, however the nice features of gauge mediation like flavour conservation etc, are lost. To preserve the nice features, gravitational contributions should become important for lighter messenger masses and should be important only for certain fields. This is possible when the hidden sector contains multiple (at least two) spurions with hierarchical vaccum expectation values. In this case, the gravitational contribtutions can be organised to be `just right'. We present a complete model with two spurion hidden sector where the gravitational contribution is from a warped flavour model in a Randall-Sundrum setting. Along the way, we present simple ...
Holographic entanglement entropy and gravitational anomalies
Castro, Alejandra; Iqbal, Nabil; Perlmutter, Eric
2014-01-01
We study entanglement entropy in two-dimensional conformal field theories with a gravitational anomaly. In theories with gravity duals, this anomaly is holographically represented by a gravitational Chern-Simons term in the bulk action. We show that the anomaly broadens the Ryu-Takayanagi minimal worldline into a ribbon, and that the anomalous contribution to the CFT entanglement entropy is given by the twist in this ribbon. The entanglement functional may also be interpreted as the worldline action for a spinning particle -- that is, an anyon -- in three-dimensional curved spacetime. We demonstrate that the minimization of this action results in the Mathisson-Papapetrou-Dixon equations of motion for a spinning particle in three dimensions. We work out several simple examples and demonstrate agreement with CFT calculations.
Lecture on Gauge Gravitation Theory. Gravity as a Higgs Field
Sardanashvily, G
2016-01-01
Gravitation theory is formulated as gauge theory on natural bundles with spontaneous symmetry breaking where gauge symmetries are general covariant transformations, gauge fields are general linear connections, and Higgs fields are pseudo-Riemannian metrics.
On the geometric foundation of classical gauge gravitation theory
G. Sardanashvily
2002-01-01
A number of recent works in E-print arXiv have addressed the foundation of gauge gravitation theory again. As is well known, differential geometry of fibre bundles provides the adequate mathematical formulation of classical field theory, including gauge theory on principal bundles. Gauge gravitation theory is formulated on the natural bundles over a world manifold whose structure group is reducible to the Lorentz group. It is the metric-affine gravitation theory where a metric (tetrad) gravit...
Gravitational anomalies in the solar system?
Iorio, Lorenzo
2015-02-01
Mindful of the anomalous perihelion precession of Mercury discovered by Le Verrier in the second half of the nineteenth century and its successful explanation by Einstein with his General Theory of Relativity in the early years of the twentieth century, discrepancies among observed effects in our Solar system and their theoretical predictions on the basis of the currently accepted laws of gravitation applied to known matter-energy distributions have the potential of paving the way for remarkable advances in fundamental physics. This is particularly important now more than ever, given that most of the universe seems to be made of unknown substances dubbed Dark Matter and Dark Energy. Should this not be directly the case, Solar system's anomalies could anyhow lead to advancements in either cumulative science, as shown to us by the discovery of Neptune in the first half of the nineteenth century, and technology itself. Moreover, investigations in one of such directions can serendipitously enrich the other one as well. The current status of some alleged gravitational anomalies in the Solar system is critically reviewed. They are: (a) Possible anomalous advances of planetary perihelia. (b) Unexplained orbital residuals of a recently discovered moon of Uranus (Mab). (c) The lingering unexplained secular increase of the eccentricity of the orbit of the Moon. (d) The so-called Faint Young Sun Paradox. (e) The secular decrease of the mass parameter of the Sun. (f) The Flyby Anomaly. (g) The Pioneer Anomaly. (h) The anomalous secular increase of the astronomical unit.
Renormalization of gauge-invariant operators and the axial anomaly
Energy Technology Data Exchange (ETDEWEB)
Espriu, D.
1983-07-15
The renormalization properties of gauge-invariant composite operators that vanish when the classical equations of motion are used (class II/sup a/ operators) and which lead to diagrams where the Adler-Bell-Jackiw anomaly occurs are discussed. It is shown that gauge-invariant operators of this kind do need, in general, nonvanishing gauge-invariant (class I) counterterms.
Universally finite gravitational and gauge theories
Directory of Open Access Journals (Sweden)
Leonardo Modesto
2015-11-01
Full Text Available It is well known that standard gauge theories are renormalizable in D=4 while Einstein gravity is renormalizable in D=2. This is where the research in the field of two derivatives theories is currently standing. We hereby present a class of weakly non-local higher derivative gravitational and gauge theories universally consistent at quantum level in any spacetime dimension. These theories are unitary (ghost-free and perturbatively renormalizable. Moreover, we can always find a simple extension of these theories that is super-renormalizable or finite at quantum level in even and odd spacetime dimensions. Finally, we propose a super-renormalizable or finite theory for gravity coupled to matter laying the groundwork for a “finite standard model of particle physics” and/or a grand unified theory of all fundamental interactions.
Universally finite gravitational and gauge theories
Modesto, Leonardo; Rachwa?, Les?aw
2015-11-01
It is well known that standard gauge theories are renormalizable in D = 4 while Einstein gravity is renormalizable in D = 2. This is where the research in the field of two derivatives theories is currently standing. We hereby present a class of weakly non-local higher derivative gravitational and gauge theories universally consistent at quantum level in any spacetime dimension. These theories are unitary (ghost-free) and perturbatively renormalizable. Moreover, we can always find a simple extension of these theories that is super-renormalizable or finite at quantum level in even and odd spacetime dimensions. Finally, we propose a super-renormalizable or finite theory for gravity coupled to matter laying the groundwork for a "finite standard model of particle physics" and/or a grand unified theory of all fundamental interactions.
Supersymmetric gauge anomaly with general homo topic paths
Energy Technology Data Exchange (ETDEWEB)
Gates, S. James E-mail: gatess@wam.umd.edu; Grisaru, Marcus T. E-mail: grisaru@brandeis.edu; Knutt, Marcia E. E-mail: knutt@physics.mcgill.ca; Penati, Silvia E-mail: silvia.penati@mi.infn.it; Suzuki, Hiroshi E-mail: hsuzuki@mito.ipc.ibaraki.ac.jp
2001-02-26
We use the method of Banerjee, Banerjee and Mitra and minimal homotopy paths to compute the consistent gauge anomaly for several superspace models of SSYM coupled to matter. We review the derivation of the anomaly for N=1 in four dimensions and then discuss the anomaly for two-dimensional models with (2,0) supersymmetry.
Supersymmetric gauge anomaly with general homo topic paths
International Nuclear Information System (INIS)
We use the method of Banerjee, Banerjee and Mitra and minimal homotopy paths to compute the consistent gauge anomaly for several superspace models of SSYM coupled to matter. We review the derivation of the anomaly for N=1 in four dimensions and then discuss the anomaly for two-dimensional models with (2,0) supersymmetry
Modification of Gravitational Anomaly Method in Hawking Radiation
Morita, Takeshi
2009-01-01
We argue an ambiguity of the derivation of the Hawking radiation through the gravitational anomaly method and propose modifications of this method such that it reproduces the correct thermal fluxes. In this modified gravitational anomaly method, we employ the two dimensional conformal field theory technique.
Modification of Gravitational Anomaly Method in Hawking Radiation
Morita, Takeshi
2009-01-01
We discuss an ambiguity of the derivation of the Hawking radiation through the gravitational anomaly method and propose modifications of this method such that it reproduces the correct thermal fluxes. In this modified gravitational anomaly method, we employ the two-dimensional conformal field theory technique.
Einstein's gravitation as a gauge theory of the Lorentz group
International Nuclear Information System (INIS)
The gauge principle in the loop space is invoked to produce the gauge theory of the Lorentz group. The full kinematics of gravitation is derived from this principle. The dynamics is introduced with a gauge ''matter field'' Lagrangian which leads to the sourceless Einstein equations. Some possibilities about quantization and implementation on the lattice are suggested
Baryon Asymmetry, Supersymmetry and Gravitational Anomalies
Ibáñez, L E; Ibanez, Luis E.; Quevedo, Fernando
1993-01-01
We discuss two independent issues about the baryon asymmetry of the universe. First, assuming that it is generated by an unspecified source at high temperatures, we study the effects of non-perturbative $SU(2)_W$ dynamics above the electroweak scale, in the context of supersymmetric models. We find that there is a substantial difference with the nonsupersymmetric case with the net effect of relaxing previous bounds on B and L violating interactions. In particular supersymmetry allows neutrino masses as large as 10 eV (preferred by solar neutrino and COBE data and measurable at future neutrino oscillation experiments). Second, we argue that the existence of a mixed lepton number-gravitational anomaly in the standard model will induce B-L violating interactions. These transitions would be catalized by Einstein-Yang-Mills instantons or sphalerons and could create a primordial B-L asymmetry at Planck temperatures or lower. Gravity (and the anomaly structure of the standard model) could then be the ultimate source...
Global gauge anomalies for simple Lie algebras
International Nuclear Information System (INIS)
We generalize the formula by Elitzur and Nair on the global-anomaly coefficients in even (D = 2n)-dimensional space and analyze global anomalies for Sp(2N), SO(N), and SU(N) groups. In particular, we show that any irreducible representation of any Sp(N) and SU(2) group has no global anomalies in D = 8k dimensions. In D = 8k+4 dimensions, SU(2) has Z2-type global anomalies only if the spin J of an irreducible representation has the form J = (12(1+4l) = 1)2, (52,9)2,... For any SU(N) group in D = 2n, the global-anomaly coefficients can be expressed in terms of so-called unstable James numbers of Stiefel manifold SU(n+1)SU(n-k) and generalized Dynkin indices Q/sub n/?1(?) for SU
The Higgs sector of gravitational gauge theories
International Nuclear Information System (INIS)
Gravitational gauge theories with de Sitter, Poincare and affine symmetry group are investigated under the aspect of the breakdown of the initial symmetry group down to the Lorentz subgroup. As opposed to the nonlinear realization approach, in the dynamical symmetry breaking procedure, the structure subgroup is not chosen arbitrarily, but is dictated by the symmetry of the groundstate of a Higgs field. We review the theory of spontaneously broken de Sitter gravity by Stelle and West and apply a similar approach to the case of the Poincare and affine groups. We will find that the Poincare case is almost trivial. The translational Higgs field reveals itself as pure gauge, i.e., it is expressed entirely in terms of the Nambu-Goldstone bosons and does not appear in the Lagrangian after the symmetry breaking. The same holds for the translational part of the affine group. The Higgs field provoking the breakdown of the general linear group leads to the determination of the Lorentzian signature of the metric in the groundstate. We show that the Higgs field remains in its groundstate, i.e., that the metric will have Lorentzian signature, unless we introduce matter fields that explicitely couple to the symmetric part of the connection. Furthermore, we present arguments that the Lorentzian signature is actually the only possible choice for physical spacetime, since the symmetry breaking mechanism works only if the stability subgroup is taken to be the Lorentz group. The other four-dimensional rotation groups are therefore ruled out not only on physical, but also on theoretical grounds. Finally, we show that some features, like the necessity of the introduction of a dilaton field, that seem artificial in the context of the affine theory, appear most natural if the gauge group is taken to be the special linear group in five dimensions. We also present an alternative model which is based on the spinor representation of the Lorentz group and is especially adopted to the description of spinor fields in a general linear covariant way, without the use of the infinite dimensional representations which are usually considered to be unavoidable
Gravitation, gauge theories and differential geometry
International Nuclear Information System (INIS)
The purpose of this article is to outline various mathematical ideas, methods, and results, primarily from differential geometry and topology, and to show where they can be applied to Yang-Mills gauge theories and Einstein's theory of gravitation.We have several goals in mind. The first is to convey to physicists the bases for many mathematical concepts by using intuitive arguments while avoiding the detailed formality of most textbooks. Although a variety of mathematical theorems will be stated, we will generally give simple examples motivating the results instead of presenting abstract proofs. Another goal is to list a wide variety of mathematical terminology and results in a format which allows easy reference. The reader then has the option of supplementing the descriptions given here by consulting standard mathematical references and articles such as those listed in the bibliography. Finally, we intend this article to serve the dual purpose of acquainting mathematicians with some basic physical concepts which have mathematical ramifications; physical problems have often stimuladed new directions in mathematical thought. (orig./WL)
Gravitational Anomalies in the Solar System?
Iorio, Lorenzo
2014-01-01
Mindful of the anomalous perihelion precession of Mercury discovered by U. Le Verrier in the second half of the nineteenth century and its successful explanation by A. Einstein with his General Theory of Relativity in the early years of the twentieth century, discrepancies among observed effects in our Solar system and their theoretical predictions on the basis of the currently accepted laws of gravitation applied to known bodies have the potential of paving the way for remarkable advances in fundamental physics. This is particularly important now more than ever, given that most of the Universe seems to be made of unknown substances dubbed Dark Matter and Dark Energy. Should this not be directly the case, Solar system's anomalies could anyhow lead to advancements in cumulative science, as shown to us by the discovery of Neptune in the first half of the nineteenth century. Moreover, investigations in one of such directions can serendipitously enrich the other one as well. The current status of some alleged gra...
Dirac Equation in Gauge and Affine-Metric Gravitation Theories
Giachetta, G.; G. Sardanashvily
1995-01-01
We show that the covariant derivative of Dirac fermion fields in the presence of a general linear connection on a world manifold is universal for Einstein's, gauge and affine-metric gravitation theories.
Gauge Invariant Effective Stress-Energy Tensors for Gravitational Waves
Anderson, Paul R.
1996-01-01
It is shown that if a generalized definition of gauge invariance is used, gauge invariant effective stress-energy tensors for gravitational waves and other gravitational perturbations can be defined in a much larger variety of circumstances than has previously been possible. In particular it is no longer necessary to average the stress-energy tensor over a region of spacetime which is larger in scale than the wavelengths of the waves and it is no longer necessary to restrict attention to high...
Hawking Radiation from Rotating Black Holes and Gravitational Anomalies
Murata, Keiju; Soda, Jiro
2006-01-01
We study the Hawking radiation from Rotating black holes from gravitational anomalies point of view. First, we show that the scalar field theory near the Kerr black hole horizon can be reduced to the 2-dimensional effective theory. Then, following Robinson and Wilczek, we derive the Hawking flux by requiring the cancellation of gravitational anomalies. We also apply this method to Hawking radiation from higher dimensional Myers-Perry black holes. In the Appendix, we present ...
Global gauge anomalies in two-dimensional bosonic sigma models
Gawedzki, Krzysztof; Waldorf, Konrad
2010-01-01
We revisit the gauging of rigid symmetries in two-dimensional bosonic sigma models with a Wess-Zumino term in the action. Such a term is related to a background closed 3-form H on the target space. More exactly, the sigma-model Feynman amplitudes of classical fields are associated to a bundle gerbe with connection of curvature H over the target space. Under conditions that were unraveled more than twenty years ago, the classical amplitudes may be coupled to the topologically trivial gauge fields of the symmetry group in a way which assures infinitesimal gauge invariance. We show that the resulting gauged Wess-Zumino amplitudes may, nevertheless, exhibit global gauge anomalies that we fully classify. The general results are illustrated on the example of the WZW and the coset models of conformal field theory. The latter are shown to be inconsistent in the presence of global anomalies. We introduce a notion of equivariant gerbes that allow an anomaly-free coupling of the Wess-Zumino amplitudes to all gauge field...
Global gauge anomaly of classical groups in even dimension
International Nuclear Information System (INIS)
Explicit expression of global gauge anomaly coefficients A(?) of locally anomaly-free representation ? of classical groups SU(N), Sp(2N) and SO(N) have been calculated in even dimensional space-time by uses of group theory and homotopy theory. As a by-product, we will prove some modular relations involving the n-th Kynkin indices Q/sub n/(?) of these groups. 11 refs
Notes on gauge theory and gravitation
International Nuclear Information System (INIS)
In order to investigate whether Einstein's general relativity theory (GRT) fits into the general scheme of a gauge theory, first the concept of a (classical) gauge theory is outlined in an introductionary spacetime approach. Having thus fixed the notation and the main properties of gauge fields, GRT is examined to find out what the gauge potentials and the corresponding gauge group might be. In this way the possibility of interpreting GRT as a gauge theory of the 4-dimensional translation group T(4) = (R4, +), and where the gauge potentials are incorporated in a T(4)-invariant way via orthonormal anholonomic basis 1-forms is considered. To include also the spin aspect a natural extension of GRT is given by gauging also the Lorentz group, whereby a Riemann-Cartan spacetime (U4-spacetime) comes into play. (Auth.)
Gravitational counterterms in an axial gauge
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All the counterterms of quantum Einstein gravity are calculated up to bilinear terms and one-loop order in an axial gauge as a sum of gauge-invariant and the Becchi-Rouet-Stora-invariant terms. Contrary to the de Donder gauge condition, ten out of thirty-three coefficients for counterterms remain undetermined in this gauge. Some relations among the counterterms, which satisfy the BRS invariance, are implicitly obtained in the course of the calculations
Gauge Theory of the Gravitational-Electromagnetic Field
Bock, Robert D.
2015-01-01
We develop a gauge theory of the combined gravitational-electromagnetic field by expanding the Poincar\\'e group to include clock synchronization transformations. We show that the electromagnetic field can be interpreted as a local gauge theory of the synchrony group. According to this interpretation, the electromagnetic field equations possess nonlinear terms and electromagnetic gauge transformations acquire a space-time interpretation as local synchrony transformations. The...
Gauge Approach to Gravitation and Regular Big Bang Theory
Minkevich, A. V.
2005-01-01
Field theoretical scheme of regular Big Bang in 4-dimensional physical space-time, built in the framework of gauge approach to gravitation, is discussed. Regular bouncing character of homogeneous isotropic cosmological models is ensured by gravitational repulsion effect at extreme conditions without quantum gravitational corrections. The most general properties of regular inflationary cosmological models are examined. Developing theory is valid, if energy density of gravitat...
Interpretation of gravitational anomalies on Mars, Venus and Earth
Tarakanov, Y. A.; Kambarov, N. S.; Prikhodko, V. A.; Bondarenko, D. R.
1984-06-01
Findings based on gravimetric observations that relate to gravitational anomalies on Mars, Venus, and Earth are presented. Results for the three planets were compared. Interpretation of the results was based on Stokes constants using figures for field characteristics in a finite number of isolated points. Details of interpretation of gravitational anomalies are given for each of three plants. The main conclusions are: there is substantial difference in the structure and nature of compression on the three planets, the Earth's lithosphere is sufficiently thin and flexible to retain the shape of a hydrostatic balanced body, the probable source of gravitational anomalies on Venus is variation in the depth of the second-phase mantle boundary, and 11 of the 13 major anomalies detected on Mars result from irregularities in the lithosphere-mantle disjunction.
Muon g-2 Anomaly and Dark Leptonic Gauge Boson
Energy Technology Data Exchange (ETDEWEB)
Lee, Hye-Sung [W& M
2014-11-01
One of the major motivations to search for a dark gauge boson of MeV-GeV scale is the long-standing muon g-2 anomaly. Because of active searches such as fixed target experiments and rare meson decays, the muon g-2 favored parameter region has been rapidly reduced. With the most recent data, it is practically excluded now in the popular dark photon model. We overview the issue and investigate a potentially alternative model based on the gauged lepton number or U(1)_L, which is under different experimental constraints.
Gerbes, M5-brane anomalies and E8 gauge theory
International Nuclear Information System (INIS)
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 ?-tildeE8, the central extension of the E8 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)
Branes as solutions of gauge theories in gravitational field
Energy Technology Data Exchange (ETDEWEB)
Zheltukhin, A.A. [Kharkov Institute of Physics and Technology, Kharkov (Ukraine); KTH Royal Institute of Technology and Stockholm University, Nordita, the Nordic Institute for Theoretical Physics, Stockholm (Sweden)
2014-09-15
The idea of the Gauss map is unified with the concept of branes as hypersurfaces embedded into D-dimensional Minkowski space. The map introduces new generalized coordinates of branes alternative to their world vectors x and identified with the gauge and other massless fields. In these coordinates the Dirac p-branes realize extremals of the Euler-Lagrange equations of motion of a (p + 1)- dimensional SO(D-p-1) gauge-invariant action in a gravitational background. (orig.)
Branes as solutions of gauge theories in gravitational field
International Nuclear Information System (INIS)
The idea of the Gauss map is unified with the concept of branes as hypersurfaces embedded into D-dimensional Minkowski space. The map introduces new generalized coordinates of branes alternative to their world vectors x and identified with the gauge and other massless fields. In these coordinates the Dirac p-branes realize extremals of the Euler-Lagrange equations of motion of a (p + 1)- dimensional SO(D-p-1) gauge-invariant action in a gravitational background. (orig.)
A Gauge Like Formulation of Gravitation and Related Issues
Sidharth, B. G.
2004-01-01
After many fruitless decades of trying to unify electromagnetism and gravitation, it is now being realized that this can be done only in discrete spacetime, as indeed the author had demonstrated. In this context, a unified description of gravitation and electromagnetism is provided within the framework of a gauge like formulation. Following the discrete spacetime structure, we then argue that the underpinning for the universe is an array of Planck scale oscillators.
More on counterterms in the gravitational action and anomalies
Taylor-Robinson, M M
2000-01-01
The addition of boundary counterterms to the gravitational action ofasymptotically anti-de Sitter spacetimes permits us to define the partitionfunction unambiguously without background subtraction. We show that theinclusion of p-form fields in the gravitational action requires the addition offurther counterterms which we explicitly identify. We also relate logarithmicdivergences in the action dependent on the matter fields to anomalies in thedual conformal field theories. In particular we find that the anomaly predictedfor the correlator of the stress energy tensor and two vector currents in fourdimensions agrees with that of the ${\\cal{N}} = 4$ superconformal SU(N) gaugetheory.
Supersymmetry, quantum gauge anomalies and generalized Chern-Simons terms in chiral gauge theory
International Nuclear Information System (INIS)
The purpose of this thesis is to investigate the interplay of anomaly cancellation and generalized Chern-Simons terms in four-dimensional chiral gauge theory. We start with a detailed discussion of generalized Chern-Simons terms with the canellation of anomalies via the Green-Schwarz mechanism. With this at hand, we investigate the situation in general N=1 supersymmetric field theories with generalized Chern-Simons terms. Two simple consistency conditions are shown to encode strong constraints on the allowed anomalies for different types of gauge groups. In one major part of this thesis we are going to display to what extent one has to modify the existing formalism in order to allow for the cancellation of quantum gauge anomalies via the Green-Schwarz mechanism. At the end of this thesis we comment on a puzzle in the literature on supersymmetric field theories with massive tensor fields. The potential contains a term that does not arise from eliminating an auxiliary field. We clarify the origin of this term and display the relation to standard D-term potential. In an appendix it is explicitly shown how these low energy effective actions might be connected to the formulation of four-dimensional gauge theories discussed at earlier stages of this thesis. (orig.)
Supersymmetry, quantum gauge anomalies and generalized Chern-Simons terms in chiral gauge theory
Energy Technology Data Exchange (ETDEWEB)
Schmidt, Torsten
2009-05-13
The purpose of this thesis is to investigate the interplay of anomaly cancellation and generalized Chern-Simons terms in four-dimensional chiral gauge theory. We start with a detailed discussion of generalized Chern-Simons terms with the canellation of anomalies via the Green-Schwarz mechanism. With this at hand, we investigate the situation in general N=1 supersymmetric field theories with generalized Chern-Simons terms. Two simple consistency conditions are shown to encode strong constraints on the allowed anomalies for different types of gauge groups. In one major part of this thesis we are going to display to what extent one has to modify the existing formalism in order to allow for the cancellation of quantum gauge anomalies via the Green-Schwarz mechanism. At the end of this thesis we comment on a puzzle in the literature on supersymmetric field theories with massive tensor fields. The potential contains a term that does not arise from eliminating an auxiliary field. We clarify the origin of this term and display the relation to standard D-term potential. In an appendix it is explicitly shown how these low energy effective actions might be connected to the formulation of four-dimensional gauge theories discussed at earlier stages of this thesis. (orig.)
Gerbes, M5-Brane Anomalies and E_8 Gauge Theory
Aschieri, P; Aschieri, Paolo; Jurco, Branislav
2004-01-01
Abelian gerbes and twisted bundles describe the topology of the NS-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 $\\tilde\\Omega E_8$, the central extension of the E_8 loop group. The twist is in general necessary to cancel global anomalies due to the nontriviality of the 11-dimensional ...
Effective QED actions: Representations, gauge invariance, anomalies, and mass expansions
International Nuclear Information System (INIS)
We analyze and give explicit representations for the effective Abelian vector gauge field actions generated by charged fermions with particular attention to the thermal regime in odd dimensions, where spectral asymmetry can be present. We show, through ?-function regularization, that both small and large gauge invariances are preserved at any temperature and for any number of fermions at the usual price of anomalies: helicity (parity) invariance will be lost in even (odd) dimensions, and in the latter even at zero mass. Gauge invariance dictates a very general 'Fourier' representation of the action in terms of the holonomies that carry the novel, large gauge-invariant, information. We show that large (unlike small) transformations and hence their Ward identities are not perturbative order-preserving, and clarify the role of (properly redefined) Chern-Simons terms in this context. From a powerful representation of the action in terms of massless heat kernels, we are able to obtain rigorous gauge-invariant expansions, for both small and large fermion masses, of its separate parity even and odd parts in arbitrary dimension. The representation also displays both the nonperturbative origin of a finite renormalization ambiguity and its physical resolution by requiring decoupling at infinite mass. Finally, we illustrate these general results by explicit computation of the effective action for some physical examples of field configurations in the three-dimensional case, where our conclusions on finite temperature effects may have physical relevance. Non-Abelian results will be presented separately. copyright 1998 The American Physical Society
Mass Gauging Demonstrator for Any Gravitational Conditions
Korman, Valentin (Inventor); Pedersen, Kevin W. (Inventor); Witherow, William K. (Inventor)
2013-01-01
The present invention is a mass gauging interferometry system used to determine the volume contained within a tank. By using an optical interferometric technique to determine gas density and/or pressure a much smaller compression volume or higher fidelity measurement is possible. The mass gauging interferometer system is comprised of an optical source, a component that splits the optical source into a plurality of beams, a component that recombines the split beams, an optical cell operatively coupled to a tank, a detector for detecting fringes, and a means for compression. A portion of the beam travels through the optical cell operatively coupled to the tank, while the other beam(s) is a reference.
Hamiltonian description of a gravitational field and gauge symmetry
International Nuclear Information System (INIS)
A hamiltonian theory of the (Einstein) gravitational field given at an arbitrary fixed space-time background is developed. The causes of the appearance of intrinsic (gauge) symmetries are explicitely indicated. It is shown that in contrast to an arbitrary field theory on a fixed background, in the theory proposed here both internal and external symmetries lead to the existence of the same constraints. The theory is applied to the problem of determining the total energy and of other quantities which are conserved in the case of an asymptotically vanishing gravitational field and a closed world configuration. The 3-covariant expressions for the integrals of motion of the systems are found
Gravitational Gauge Theory and the Existence of Time
International Nuclear Information System (INIS)
General relativity may be formulated as a gauge theory more than one way using the quotient manifold approach. We contrast the structures that arise in four gravitational gauge theories, three of which give satisfactory gauge theoris of general relativity. Of particular interest is the quotient of the conformal group of a flat space by its Weyl subgroup, which always has natural symplectic and metric structures in addition to the requisite manifold. This quotient space admits canonically conjugate, orthogonal, metric submanifolds distinct from the original space if and only if the original flat space has signature n, -n or 0. In the Euclidean cases, the resultant configuration space must be Lorentzian. This gives a 1-1 mapping between Euclidean and Lorentzian submanifolds, with induced Euclidean gravity or general relativity, respectively
Gravitational anomalies and one-dimensional behavior of black holes
Energy Technology Data Exchange (ETDEWEB)
Majhi, Bibhas Ranjan, E-mail: bibhas.majhi@iitg.ernet.in [Department of Physics, Indian Institute of Technology Guwahati, 781039, Guwahati, Assam (India)
2015-12-08
It has been pointed out by Bekenstein and Mayo that the behavior of the black holeâ€™s entropy or information flow is similar to information flow through one-dimensional channel. Here I analyze the same issue with the use of gravitational anomalies. The rate of the entropy change (S{sup .}) and the power (P) of the Hawking emission are calculated from the relevant components of the anomalous stress tensor under the Unruh vacuum condition. I show that the dependence of S{sup .} on the power is S{sup .} âˆP{sup 1/2}, which is identical to that for the information flow in a one-dimensional system. This is established by using the (1+1)-dimensional gravitational anomalies first. Then the fact is further bolstered by considering the (1+3)-dimensional gravitational anomalies. It is found that, in the former case, the proportionality constant is exactly identical to the one-dimensional situation, known as Pendryâ€™s formula, while in the latter situation its value decreases.
Gravitational anomalies and one-dimensional behavior of black holes
International Nuclear Information System (INIS)
It has been pointed out by Bekenstein and Mayo that the behavior of the black hole’s entropy or information flow is similar to information flow through one-dimensional channel. Here I analyze the same issue with the use of gravitational anomalies. The rate of the entropy change (S.) and the power (P) of the Hawking emission are calculated from the relevant components of the anomalous stress tensor under the Unruh vacuum condition. I show that the dependence of S. on the power is S. ?P1/2, which is identical to that for the information flow in a one-dimensional system. This is established by using the (1+1)-dimensional gravitational anomalies first. Then the fact is further bolstered by considering the (1+3)-dimensional gravitational anomalies. It is found that, in the former case, the proportionality constant is exactly identical to the one-dimensional situation, known as Pendry’s formula, while in the latter situation its value decreases
The approximate solution with torsion for a charged particle in a gauge theory of gravitation
International Nuclear Information System (INIS)
In this paper a method of finding an approximate solution of field equations in a gauge theory of gravitation is given by means of physical considerations. Using this method, an approximate solution of the field of a charged particle in a gauge theory of gravitation, a space-time metric and torsion tensors, is obtained. This method can also be used to solve field equations in other gauge theories of gravitation. (author)
Gravitational anomalies, entanglement entropy, and flat-space holography
Hosseini, Seyed Morteza
2015-01-01
We introduce a prescription to compute the entanglement entropy of Galilean conformal field theories by combining gravitational anomalies and an \\.{I}n\\"{o}n\\"{u}-Wigner contraction. Using this proposal, we calculate the entanglement entropy for a class of Galilean conformal field theories, which are believed to be dual to three-dimensional flat-space cosmological solutions. These geometries describe expanding (contracting) universes and can be viewed as the flat-space limit of rotating BTZ black holes. We show that our finding reduces, in the appropriate limits, to the results discussed in the literature and provide interpretations for the previously unexplored regimes, such as flat-space chiral gravity.
Hawking Radiation and Covariant Anomalies
Banerjee, Rabin; Kulkarni, Shailesh
2007-01-01
Generalising the method of Wilczek and collaborators we provide a derivation of Hawking radiation from charged black holes using only covariant gauge and gravitational anomalies. The reliability and universality of the anomaly cancellation approach to Hawking radiation is also discussed.
No black holes: A gravitational gauge theory possibility
International Nuclear Information System (INIS)
The most general lowest order lagrangian that can be formed from gauge-derived vierbein invariants is constrained by the hypothesis that the speed of light as measured by conventional rods and clocks of atomic constitution is independent of direction in a gravitational field. It is shown that the standard weak field observational tests of general relativity serve to eliminate all possible combinations of parameters in this constrained lagrangian except two. One parameter choice gives the isotropic Schwarzschild black hole metric of the general theory of relativity. The other allowable choice leads to an exponential metric of the class proposed by Yilmaz, corresponding in strong fields to large red shifts without black hole formation. (orig.)
Parity anomaly in D=3 Chern-Simons gauge theory
International Nuclear Information System (INIS)
Ultraviolet divergences are calcelled in the effective action of the D=3 Chern-Simons gauge theory but regularization is needed. It is impossible to introduce gauge invariant regularization and conserve the parity of the classical action. As a result, in the limit when regularization is moved the finite contribution to the effective action induced by parity violating regulators remains. 18 refs
On the definiteness of the conformal anomaly in nonconformal gauges
Mödritsch, W
1993-01-01
The critical dimension of the bosonic string in the harmonic and the deDonder gauge may be calculated from the time ordered product of two energy momentum tensors. We show that recently found ambiguities within that method in nonconformal gauges can be resolved by a treatment respecting background covariance.
Stochastic quantization and gauge-fixing of the linearized gravitational field
International Nuclear Information System (INIS)
Due to the indefiniteness of the Euclidean gravitational action the Parisi-Wu stochastic quantization scheme fails in the case of the gravitational field. Therefore we apply a recently proposed modification of stochastic quantization that works in Minkowski space and preserves all the advantages of the original Parisi-Wu method; in particular no gauge-fixing is required. Additionally stochastic gauge-fixing may be introduced and is also studied in detail. The graviton propagators obtained with and without stochastic gauge-fixing all exhibit a noncausal contribution, but apart from this effect the gauge-invariant quantities are the same as those of standard quantization. (Author)
Space-time dependent couplings In N = 1 SUSY gauge theories: Anomalies and central functions
International Nuclear Information System (INIS)
We consider N = 1 supersymmetric gauge theories in which the couplings are allowed to be space-time dependent functions. Both the gauge and the superpotential couplings become chiral superfields. As has recently been shown, a new topological anomaly appears in models with space-time dependent gauge coupling. Here we show how this anomaly may be used to derive the NSVZ ?-function in a particular, well-determined renormalisation scheme, both without and with chiral matter. Moreover we extend the topological anomaly analysis to theories coupled to a classical curved superspace background, and use it to derive an all-order expression for the central charge c, the coefficient of the Weyl tensor squared contribution to the conformal anomaly. We also comment on the implications of our results for the central charge a expected to be of relevance for a four-dimensional C-theorem. (author)
Gravitational anomalies in higher dimensional Riemann-Cartan space
Energy Technology Data Exchange (ETDEWEB)
Yajima, S [Department of Physics, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan); Tokuo, S [Department of Physics, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan); Fukuda, M [Department of Physics, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan); Higashida, Y [Takuma National College of Technology, 551 kohda, Takuma-cho, Mitoyo, Kagawa 769-1192 (Japan); Kamo, Y [Radioisotope Center, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Kubota, S-I [Computing and Communications Center, Kagoshima University, 1-21-35 Koorimoto, Kagoshima 890-0065 (Japan); Taira, H [Department of Physics, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan)
2007-02-21
By applying the covariant Taylor expansion method of the heat kernel, the covariant Einstein anomalies associated with a Weyl fermion of spin 1/2 in four-, six- and eight-dimensional Riemann-Cartan space are manifestly given. Many unknown terms with torsion tensors appear in these anomalies. The Lorentz anomaly is intimately related to the Einstein anomaly even in Riemann-Cartan space. The explicit form of the Lorentz anomaly corresponding to the Einstein anomaly is also obtained.
Hawking Radiation from Black Holes of Constant Negative Curvature via Gravitational Anomalies
Skamagoulis, Petros
2010-01-01
I derive the Hawking flux from black holes of constant negative curvature and from a black hole of constant negative curvature conformally coupled to a scalar field, using the covariant gravitational anomalies method.
Gravitation as a Super SL(2,C) Gauge Theory
Tung, R S
2001-01-01
We present a gauge theory of the super SL(2,C) group. The gauge potential is a connection of the Super SL(2,C) group. A MacDowell-Mansouri type of action is proposed where the action is quadratic in the Super SL(2,C) curvature and depends purely on gauge connection. By breaking the symmetry of the Super SL(2,C) topological gauge theory to SL(2,C), a metric is naturally defined.
Gauge-invariant definition of gravitational radiation in Robertson-Walker cosmologies
International Nuclear Information System (INIS)
Gauge-invariant quantities are introduced which relate directly to the ideal fluid perturbations in Robertson-Walker backgrounds. It is shown how the vanishing of these gauge invariants is equivalent to the definition of purely radiative perturbations found in some early works. If one imposes a regularity condition, then the vanishing of just four gauge invariants is sufficient to define the condition of no perturbation of matter. The latter result is used to clarify the relationship to Hawking's definition of gravitational radiation
International Nuclear Information System (INIS)
Fermion one-loop corrections to the commutators of the gauge field, the electric field, and the charge density with the total Hamiltonian are evaluated by the Bjorken-Johnson-Low method in chiral gauge theories. It turns out that individual terms of the Hamiltonian give anomalous terms to the commutator with the electric field, but the total Hamiltonian does not. That is, the classical equation of motion for the electric field holds as the Heisenberg equation. The current-divergence anomaly is identified with the anomalous terms of the commutator between the charge density and the total Hamiltonian. These two results are combined to show that the time derivative of the Gauss-law operator amounts to the current-divergence anomaly (Fujikawa's relation)
A Class of Anomaly-Free Gauge Theories
Roepstorff, G
2000-01-01
We report on a detailed calculation of the anomaly coefficients for the odd and even parts of the $Z_2$-graded representation $\\theta$ of the Lie algebra Lie$ G$ on the exterior algebra of dimension $2^n$ assuming that $G\\subset U(n)$. The coefficients vanish provided $G\\subset SU(n)$ and $n\
Consistent and covariant gauge anomalies as solutions of the same extended algebraic problem
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We show that the usual consistent and covariant gauge anomalies are different solutions of the same algebraic problem related to the complex noncompact extension of the vector and axial vector gauge group. They are obtained as nontrivial integrals of the relevant Wess-Zumino consistency conditions as well as representations of the algebra of generators acting as functional differential operators upon a fermionic effective action extended to complex vector and axial vector potentials. (orig.)
Can, T; Laskin, M; Wiegmann, P
2014-07-25
We develop a general method to compute correlation functions of fractional quantum Hall (FQH) states on a curved space. In a curved space, local transformation properties of FQH states are examined through local geometric variations, which are essentially governed by the gravitational anomaly. Furthermore, we show that the electromagnetic response of FQH states is related to the gravitational response (a response to curvature). Thus, the gravitational anomaly is also seen in the structure factor and the Hall conductance in flat space. The method is based on an iteration of a Ward identity obtained for FQH states. PMID:25105643
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A new type of anomaly is discussed that afflicts certain non-linear sigma models with fermions. This anomaly is similar to the ordinary gauge and gravitational anomalies since it reflects a topological obstruction to the reparametrization invariance of the quantum effective action. Nonlinear sigma models are constructed based on homogeneous spaces G/H. Anomalies arising when the fermions are chiral are shown to be cancelled sometimes by Chern-Simons terms. Nonlinear sigma models are considered based on general Riemannian manifolds. 9 refs
Subtlety in the anomaly calculation of string theory in the harmonic gauge
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Recently, Takahashi has perturbatively obtained BRS anomaly in the string theory based on the two-dimensional quantum gravity in the harmonic gauge. This result is in contradiction with the exact one established previously in the Heisenberg picture. The reason for the discrepancy is shown to be attributable to the ambiguity of evaluating massless Feynman integrals. Hence, perturbative approach should be abandoned. (author)
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The anomaly cancellation method proposed by Wilczek et al. is applied to the general charged rotating black holes in five-dimensional minimal gauged supergravity. Thus Hawking temperature and fluxes are found. The Hawking temperature obtained agrees with the surface gravity formula. The black holes have charge and two unequal angular momenta, and these give rise to appropriate terms in the effective U(1) gauge field of the reduced (1+1)-dimensional theory. In particular, it is found that the terms in this U(1) gauge field correspond exactly to the correct electrostatic potential and the two angular velocities on the horizon of the black holes, and so the results for the Hawking fluxes derived here from the anomaly cancellation method are in complete agreement with the ones obtained from integrating the Planck distribution.
Adler-Bardeen theorem and manifest anomaly cancellation to all orders in gauge theories
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We reconsider the Adler-Bardeen theorem for the cancellation of gauge anomalies to all orders, when they vanish at one loop. Using the Batalin-Vilkovisky formalism and combining the dimensional-regularization technique with the higher-derivative gauge invariant regularization, we prove the theorem in the most general perturbatively unitary renormalizable gauge theories coupled to matter in four dimensions, and we identify the subtraction scheme where anomaly cancellation to all orders is manifest, namely no subtractions of finite local counterterms are required from two loops onwards. Our approach is based on an order-by-order analysis of renormalization, and, differently from most derivations existing in the literature, does not make use of arguments based on the properties of the renormalization group. As a consequence, the proof we give also applies to conformal field theories and finite theories. (orig.)
Overconnections and the energy-tensors of gauge and gravitational fields
Canarutto, Daniel
2015-01-01
A geometric construction for obtaining a prolongation of a connection to a connection of a bundle of connections is presented. This determines a natural extension of the notion of canonical energy-tensor which suits gauge and gravitational fields, and shares the main properties of the energy-tensor of a matter field in the jet space formulation of Lagrangian field theory, in particular with regards to symmetries of the Poincar\\'e-Cartan form. Accordingly, the joint energy-tensor for interacting matter and gauge fields turns out to be a natural geometric object, whose definition needs no auxuliary structures. Various topics related to energy-tensors, symmetries and the Einstein equations in a theory with interacting matter, gauge and gravitational fields can be viewed under a clarifying light. Finally, the symmetry determined by the "Komar super potential" is expressed as a symmetry of the gravitational Poincar\\'e-Cartan form.
The geometrical and gauge structure of a generalized theory of gravitation
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A generalized theory of gravitation is constructed in a superspace base manifold of eight dimensions with an octad of gauge fields and a superspace fiber bundle connection. The gauge structure is a non-compact unitary group U(i,j) contains SU(3) x SU(2) x U(1) which can be used as a unification scheme. Field equations with uniquely determined sources are derived from an action principle
Gauge theories of gravitation a reader with commentaries
Blagojevic, Milutin
2013-01-01
In the last five decades, the gauge approach to gravity has represented a research area of increasing importance for our understanding of the physics of fundamental interactions. A full clarification of the gauge dynamics of gravity is expected to be the last missing link to the hidden structure of a consistent unification of all the fundamental interactions, based on the gauge principle. The aim of the present reprint volume, with commentaries by Milutin Blagojevi & 263; and Friedrich W Hehl, is to introduce graduate and advanced undergraduate students of theoretical or mathematical physics, or any other interested researcher, to the field of classical gauge theories of gravity. This is not just an ordinary reprint volume; it is a guide to the literature on gauge theories of gravity. The reader is encouraged first to study the introductory commentaries and to become familiar with the basic content of the reprints and related ideas, then he/she can choose to read a specific reprint or reprints, and after ...
Gauge theory duals of black hole â€“ black string transitions of gravitational theories on a circle
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We study the black hole â€“ black string phase transitions of gravitational theories compactified on a circle using the holographic duality conjecture. The gauge theory duals of these theories are maximally supersymmetric and strongly coupled 1 + 1 dimensional SU(N) Yang-Mills theories compactified on a circle, in the large N limit. We perform the strongly coupled finite temperature gauge theory calculations on a lattice, using the recently developed exact lattice supersymmetry methods based on topological twisting and orbifolding. The spatial Polyakov line serves as relevant order parameter of the confinement â€“ deconfinement phase transitions in the gauge theory duals
Gauge theory duals of black hole - black string transitions of gravitational theories on a circle
Catterall, Simon; Wiseman, Toby
2010-01-01
We study the black hole - black string phase transitions of gravitational theories compactified on a circle using the holographic duality conjecture. The gauge theory duals of these theories are maximally supersymmetric and strongly coupled 1 + 1 dimensional SU(N) Yang-Mills theories compactified on a circle, in the large $N$ limit. We perform the strongly coupled finite temperature gauge theory calculations on a lattice, using the recently developed exact lattice supersymmetry methods based on topological twisting and orbifolding. The spatial Polyakov line serves as relevant order parameter of the confinement - deconfinement phase transitions in the gauge theory duals.
Gravitational and gauge couplings in Chern-Simons fractional spin gravity
Boulanger, Nicolas; Valenzuela, Mauricio
2015-01-01
We propose an extension of Vasiliev's supertrace operation for the enveloping algebra of Wigner's deformed oscillator algebra to the fractional spin algebra given in arXiv:1312.5700. The resulting three-dimensional Chern-Simons theory unifies the Blencowe-Vasiliev higher spin gravity with fractional spin fields and internal gauge potentials. For integer or half-integer fractional spins, infinite dimensional ideals arise and decouple, leaving finite dimensional gauge algebras gl(2l+1) or gl(l|l+1) and various real forms thereof. We derive the relation between gravitational and internal gauge couplings.
Gravitational matter-antimatter asymmetry and four-dimensional Yang-Mills gauge symmetry
Hsu, J. P.
1981-01-01
A formulation of gravity based on the maximum four-dimensional Yang-Mills gauge symmetry is studied. The theory predicts that the gravitational force inside matter (fermions) is different from that inside antimatter. This difference could lead to the cosmic separation of matter and antimatter in the evolution of the universe. Moreover, a new gravitational long-range spin-force between two fermions is predicted, in addition to the usual Newtonian force. The geometrical foundation of such a gravitational theory is the Riemann-Cartan geometry, in which there is a torsion. The results of the theory for weak fields are consistent with previous experiments.
Hawking radiation from gravity's rainbow via gravitational anomaly
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Based on the anomaly cancellation method, initiated by Robinson and Wilczek, we investigates Hawking radiation from the modified Schwarzschild black hole from gravity's rainbow from the anomaly point of view. Unlike the general Schwarzschild space—time, the metric of this black hole depends on the energies of probes. The obtained result shows to restore the underlying general covariance at the quantum level in the effective field, the covariant compensating flux of energy—momentum tensor, which is related to the energies of the probes, should precisely equal to that of a (1 + 1)-dimensional blackbody at the Hawking temperature
Path-dependent formulation of gravitation as a gauge theory
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A satisfactory description of Riemann-Cartan U4 manifolds is obtained as a gauge theory associated with the Poincare group and formulated in flat space-time. The formulation does not introduce any ad hoc prescription to identify the tetrads. The connection with the usual local descriptions is also worked out explicitly
Conservation laws in the SLsub(2,C) gauge theory of gravitation
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A one-parameter family of new Lagrangian densities for the SLsub(2,C) gauge theory of gravitation is proposed. The relation between the laws of conservation and the SLsub(2,C) symmetry of general relativity through the Noether theorem is investigated
Gravitational Anomalies by HTC Superconductors a 1999 Theoretical Status Report
Modanese, G
1999-01-01
In this report we summarize in an informal way the main advances made in the last 3 years and give a unified scheme of our theoretical work. This scheme aims at connecting in a consistent physical picture (by the introduction of some working hypotheses when necessary) the technical work published in several single articles. The part of our model concerning the purely gravitational aspects of the weak shielding phenomenon is almost complete; the part concerning the density distribution of the superconducting carriers in the HTC disks is still qualitative, also due to the very non-standard character of the experimental setup. The main points of our analysis are the following: coherent coupling between gravity and a Bose condensate; induced gravitational instability and "runaway" of the field, with modification of the static potential; density distribution of the superconducting charge carriers; energetic balance; effective equations for the field; existence of a threshold density.
Gravitationally violated U(1) symmetry and neutrino anomalies
Joshipura, Anjan S.
1998-01-01
The current searches for neutrino oscillations seem to suggest an approximate $L_e-L_\\m-L_{\\tau}$ flavor symmetry. This symmetry implies a pair of degenerate neutrinos with mass $m_0$ and large leptonic mixing. We explore the possibility that gravitational interactions break this global symmetry. The Planck scale suppressed breaking of the $L_e-L_\\m-L_{\\tau}$ symmetry is shown to lead to the right amount of splitting among the degenerate neutrinos needed in order to solve th...
External gauge invariance and anomaly in BS vertices and bound states
Bando, M; Kugo, T; Masako Bando; Masayasu Harada; Taichiro Kugo
1993-01-01
A systematic method is given for obtaining consistent approximations to the Schwinger-Dyson(SD) and Bethe-Salpeter(BS) equations which maintain the external gauge invariance. We show that for any order of approximation to the SD equation there is a corresponding approximation to the BS equations such that the solutions to those equations satisfy the Ward-Takahashi identities of the external gauge symmetry. This formulation also clarifies the way how we can calculate the Green functions of current operators in a consistent manner with the gauge invariance and the axial anomaly. We show which type of diagrams for the $\\pi^0\\rightarrow\\gamma\\gamma$ amplitude using the pion BS amplitude give result consistent with the low-energy theorem. An interesting phenomenon is observed in the ladder approximation that the low energy theorem is saturated by the zeroth order terms in the external momenta of the pseudoscalar BS amplitude and the vector vertex functions.
Gauged Two Higgs Doublet Model confronts the LHC 750 GeV di-photon anomaly
Huang, Wei-Chih; Yuan, Tzu-Chiang
2015-01-01
In light of the recent 750 GeV di-photon anomaly observed at the LHC, we check the possibility of accommodating the deviation from the Standard Model~(SM) prediction based on the Gauged Two Higgs Doublet Model, which has been proposed lately. The model embeds two Higgs doublets into a doublet of a non-abelian gauge group $SU(2)_H$, while the SM $SU(2)_L$ right-handed fermion singlets are paired up with new heavy fermions to form $SU(2)_H$ doublets, and $SU(2)_L$ left-handed fermion doublets are singlets under $SU(2)_H$. An $SU(2)_H$ scalar doublet, which provides a mass to the new heavy fermions as well as the $SU(2)_H$ gauge bosons, can be produced via gluon fusion and subsequently decays into two photons with the help of the new fermions to account for the deviation from the SM prediction.
Gauge fields arising from spacetime symmetries and gravitational theories. I
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The Utiyama method of obtaining an interaction from an invariance principle is applied in the case of external (spacetime) symmetries. The ''gauge'' fields arising from a spacetime symmetry with respect to a general N-parameter Lie group are introduced following Kibble's extension. The corresponding formulas are obtained, which are more general than Kibble's and are reduced to Kibble's if we identify the generic N-parameter group with the Poincare 10-parameter group
Gravitational duality in MacDowell-Mansouri gauge theory
García-Compeán, H.; Obregón, O.; Ramírez, C.
1998-11-01
Strong-weak duality invariance can only be defined for particular sectors of supersymmetric Yang-Mills theories. Nevertheless, for full non-Abelian nonsupersymmetric theories, dual theories with inverted couplings have been found. We show that an analogous procedure allows us to find the dual action to the gauge theory of gravity constructed by the MacDowell-Mansouri model plus the superposition of a ? term.
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A systematic method is developed to study the classical motion of a mass point in gravitational gauge field. First, by using Mathematica, a spherical symmetric solution of the field equation of gravitational gauge field is obtained, which is just the traditional Schwarzschild solution. Combining the principle of gauge covariance and Newton's second law of motion, the equation of motion of a mass point in gravitational field is deduced. Based on the spherical symmetric solution of the field equation and the equation of motion of a mass point in gravitational field, we can discuss classical tests of gauge theory of gravity, including the deflection of light by the sun, the precession of the perihelia of the orbits of the inner planets and the time delay of radar echoes passing the sun. It is found that the theoretical predictions of these classical tests given by gauge theory of gravity are completely the same as those given by general relativity.
Anomaly-free discrete gauge symmetries in Froggatt-Nielsen models
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Luhn, C.
2006-05-15
Discrete symmetries (DS) can forbid dangerous B- and L-violating operators in the supersymmetric Lagrangian. Due to the violation of global DSs by quantum gravity effects, the introduced DS should be a remnant of a spontaneously broken local gauge symmetry. Demanding anomaly freedom of the high-energy gauge theory, we determine all family-independent anomaly-free Z{sub N} symmetries which are consistent with the trilinear MSSM superpotential terms in Part I. We find one outstanding Z{sub 6} symmetry, proton hexality P{sub 6}, which prohibits all B- and L-violating operators up to dimension five, except for the Majorana neutrino mass terms LH{sub u}LH{sub u}. In Part II, we combine the idea that a DS should have a gauge origin with the scenario of Froggatt and Nielsen (FN). We construct concise U(1){sub X} FN models in which the Z{sub 3} symmetry baryon triality, B{sub 3}, arises from U(1){sub X} breaking. We choose this specific DGS because it allows for R-parity violating interactions; thus neutrino masses can be explained without introducing right-handed neutrinos. We find six phenomenologically viable B{sub 3}-conserving FN models. (orig.)
Anomaly-free discrete gauge symmetries in Froggatt-Nielsen models
International Nuclear Information System (INIS)
Discrete symmetries (DS) can forbid dangerous B- and L-violating operators in the supersymmetric Lagrangian. Due to the violation of global DSs by quantum gravity effects, the introduced DS should be a remnant of a spontaneously broken local gauge symmetry. Demanding anomaly freedom of the high-energy gauge theory, we determine all family-independent anomaly-free ZN symmetries which are consistent with the trilinear MSSM superpotential terms in Part I. We find one outstanding Z6 symmetry, proton hexality P6, which prohibits all B- and L-violating operators up to dimension five, except for the Majorana neutrino mass terms LHuLHu. In Part II, we combine the idea that a DS should have a gauge origin with the scenario of Froggatt and Nielsen (FN). We construct concise U(1)X FN models in which the Z3 symmetry baryon triality, B3, arises from U(1)X breaking. We choose this specific DGS because it allows for R-parity violating interactions; thus neutrino masses can be explained without introducing right-handed neutrinos. We find six phenomenologically viable B3-conserving FN models. (orig.)
SL(2,C) Gauge Theory of Gravitation and the Quantization of the Gravitational Field
Carmeli, Moshe; Malin, Shimon
1999-01-01
A new approach to quantize the gravitational field is presented. It is based on the observation that the quantum character of matter becomes more significant as one gets closer to the big bang. As the metric loses its meaning, it makes sense to consider Schrodinger's three generic types of manifolds - unconnected differentiable, affinely connected, and metrically connected - as a temporal sequence following the big bang. Hence one should quantize the gravitational field on g...
Axial vacuum symmetry of the unified gauge theories with the gravitational mechanism of instability
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The problem of stable-state determination is considered in unified gauge theories involving gravitation. The gravitational fields are examined at a classical level. The self-consistent set of field equations is studied in the semiclassical approach. A new determination of stable states is given. If the conditions of the determination are not satisfied then the vacuum state may be metastable. For the case of axial symmetry the metastable Z-type states are shown to cancel if these states are symmetric. (author)
Geometrodynamics of gauge fields on the geometry of Yang-Mills and gravitational gauge theories
Mielke, Eckehard W
2016-01-01
This monograph aims to provide a unified, geometrical foundation of gauge theories of elementary particle physics. The underlying geometrical structure is unfolded in a coordinate-free manner via the modern mathematical notions of fibre bundles and exterior forms. Topics such as the dynamics of Yang-Mills theories, instanton solutions and topological invariants are included. By transferring these concepts to local space-time symmetries, generalizations of Einstein's theory of gravity arise in a Riemann-Cartan space with curvature and torsion. It provides the framework in which the (broken) Poincaré gauge theory, the Rainich geometrization of the Einstein-Maxwell system, and higher-dimensional, non-abelian Kaluza-Klein theories are developed. Since the discovery of the Higgs boson, concepts of spontaneous symmetry breaking in gravity have come again into focus, and, in this revised edition, these will be exposed in geometric terms. Quantizing gravity remains an open issue: formulating it as a de Sitter t...
Gauge theory and gravitation: an approach to a fiber bundle formalism
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The thesis is composed of two different parts. A formal complete and rigorous mathematical part-of topics of differential manilfolds, exterior calculus, riemannian geometry, principal fiber bundle (p.f.) with connections and linear connections and a second part of application of this mathematical formalism concerning physical theories, particularly the Maxwell eletromagnetism (EM), gauge theory of Yang-Mills (Y-M), the GRT, and the gravitation theory of Einstein-Cartan. (E.C.)
Gauge-invariant gravitational wave modes in pre-big bang cosmology
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The t<0 branch of pre-big bang cosmological scenarios is subject to a gravitational wave instability. The unstable behaviour of tensor perturbations is derived in a very simple way in Hwang's covariant and gauge-invariant formalism developed for extended theories of gravity. A simple interpretation of this instability as the effect of an ''antifriction'' is given, and it is argued that a universe must eventually enter the expanding phase. (orig.)
Hawking radiation from the Schwarzschild black hole with a global monopole via gravitational anomaly
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This paper derives the Hawking flux from the Schwarzschild black hole with a global monopole by using Robinson and Wilczek's method. Adopting a dimensional reduction technique, it can describe the effective quantum field in the (3 + 1)-dimensional global monopole background by an infinite collection of the (1 + 1)-dimensional massless fields if neglecting the ingoing modes near the horizon, where the gravitational anomaly can be cancelled by the (1 + 1)-dimensional black body radiation at the Hawking temperature
Global anomalies in six dimensions
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Applying Witten's formula for global gauge and gravitational anomalies to 6-dimensional supergravities, the authors find: the perturbatively anomaly free N = 4 chiral supergravity coupled to 21 tensor multiplets is global anomaly free for any choice of space-time manifold with vanishing third Betti number (b3); the perturbatively anomaly free matter coupled N = 2 chiral supergravities with arbitrary number of tensor multiplets, whose Yang-Mills gauge groups do no include G2, SU(2), or SU(3) are free of global anomalies if the theory is formulated on S6. In the case of 9 tensor multiplets coupled to supergravity, this result holds for any space-time with vanishing b3. The N = 6 chiral supergravity has perturbative gravitational anomalies and therefore the global anomalies need not be considered in this case
Rose, Luigi Delle
2013-01-01
The principal goal of the physics of the fundamental interactions is to provide a consistent description of the nature of the subnuclear forces, which manifest in our universe, together with the gravitational force, in a unified framework. This attempt, which is far from being complete, is characterized by two milestones, the Standard Model of the elementary particles and the Einstein's theory of General Relativity. The coupling of a quantum field theory, such as the Standard Model, to a weak gravitational background provides significant information concerning the coupling of matter to gravity and allows to study in a systematic way the origin of the conformal anomaly. For this reason, the computation of correlation functions in a weak gravitational background is of remarkable interest and the consequences of this analysis are also of phenomenological relevance. For instance, they concern the appearance in the spectrum of the theory of a composite state, the dilaton, which is identified, in perturbation theor...
Neveu-Schwarz 5-branes in type-IIA supergravity and gravitational anomalies
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We construct a gravitational-anomaly-free effective action for the coupled system of type-IIA D=10 dynamical supergravity interacting with a NS5-brane. The NS5-brane is considered as elementary in that the associated current is a ? function supported on its world volume. Our approach is based on a Chern kernel which encodes the singularities of the three-form field strength near the brane in an SO(4)-invariant way and provides a solution for its Bianchi identity in terms of a two-form potential. A dimensional reduction of the recently constructed anomaly-free effective action for an elementary M5-brane in D=11 is seen to reproduce our ten-dimensional action. The Chern-kernel approach provides in particular a concrete realization of the anomaly cancellation mechanism envisaged by Witten
Li, Tianjun
2010-01-01
In Grand Unified Theories (GUTs) from orbifold and various string constructions the generic vector-like particles do not need to form complete SU(5) or SO(10) representations. To realize them concretely, we present orbifold SU(5) models, orbifold SO(10) models where the gauge symmetry can be broken down to flipped SU(5) X U(1)_X or Pati-Salam SU(4)_C X SU(2)_L X SU(2)_R gauge symmetries, and F-theory SU(5) models. Interestingly, these vector-like particles can be at the TeV-scale so that the lightest CP-even Higgs boson mass can be lifted, or play the messenger fields in the Gauge Mediated Supersymmetry Breaking (GMSB). Considering GMSB, ultraviolet insensitive Anomaly Mediated Supersymmetry Breaking (AMSB), and the deflected AMSB, we study the general gaugino mass relations and their indices, which are valid from the GUT scale to the electroweak scale at one loop, in the SU(5) models, the flipped SU(5) X U(1)_X models, and the Pati-Salam SU(4)_C X SU(2)_L X SU(2)_R models. In the deflected AMSB, we also defi...
Gravitational energy for GR and Poincaré gauge theories: A covariant Hamiltonian approach
Chen, Chiang-Mei; Nester, James M.; Tung, Roh-Suan
2015-08-01
Our topic concerns a long standing puzzle: The energy of gravitating systems. More precisely we want to consider, for gravitating systems, how to best describe energy-momentum and angular momentum/center-of-mass momentum (CoMM). It is known that these quantities cannot be given by a local density. The modern understanding is that (i) they are quasi-local (associated with a closed 2-surface), (ii) they have no unique formula, (iii) they have no reference frame independent description. In the first part of this work, we review some early history, much of it not so well known, on the subject of gravitational energy in Einstein's general relativity (GR), noting especially Noether's contribution. In the second part, we review (including some new results) much of our covariant Hamiltonian formalism and apply it to Poincaré gauge theories of gravity (PG), with GR as a special case. The key point is that the Hamiltonian boundary term has two roles, it determines the quasi-local quantities, and furthermore, it determines the boundary conditions for the dynamical variables. Energy-momentum and angular momentum/CoMM are associated with the geometric symmetries under Poincaré transformations. They are best described in a local Poincaré gauge theory. The type of spacetime that naturally has this symmetry is Riemann-Cartan spacetime, with a metric compatible connection having, in general, both curvature and torsion. Thus our expression for the energy-momentum of physical systems is obtained via our covariant Hamiltonian formulation applied to the PG.
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Using anomalous viewpoint, we study the Hawking radiation from a kind of topological Kerr Anti-de-Sitter (Kerr-AdS) black hole with one rotational parameter. We employ the covariant gauge and gravitational anomalies. The result supports the Robinson–Wilczek opinion and shows that the Hawking temperature can be correctly determined by cancelling covariant gauge and gravitational anomalies at the horizon
Anomalies and Transport Coefficients: The Chiral Gravito-Magnetic Effect
Landsteiner, Karl; Pena-Benitez, Francisco
2011-01-01
Axial anomalies give rise to interesting new transport phenomena such as the "chiral magnetic effect". We discuss how the associated transport coefficients can be studied via Kubo formulas at weak and strong coupling, the latter via gauge gravity duality. We argue for a new "chiral gravito-magnetic" (or vortical) effect sensitive to the presence of mixed gauge-gravitational anomalies.
Conserved vector current of the SL(2,C) gauge theory of gravitation and Noether's theorem
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In the SL(2,C) gauge theory of gravitation one obtains a conserved vector current which is analogous to the isotropic spin current of the ordinary SU(2) Yang-Mills theory. In a recent paper Malin has shown that the gravitational conserved current can be defined, and its conservation can be proved, in a spinor affine spacetime without assuming the existence of a metric tensor, and that a metric structure is required to obtain a decomposition of the current as a sum of contributions of the sources and of the graviational field itself. In this paper we apply Noether's theorem to obtain a general SL(2,C) invariant form of this conserved current. (orig.)
Anomalies of Density, Stresses, and the Gravitational Field in the Interior of Mars
Chuikova, N A; Maksimova, T G; 10.3103/S0027134912020075
2012-01-01
We determined the possible compensation depths for relief harmonics of different degrees and orders. The relief is shown to be completely compensated within the depth range of 0 to 1400 km. The lateral distributions of compensation masses are determined at these depths and the maps are constructed. The possible nonisostatic vertical stresses in the crust and mantle of Mars are estimated to be 64 MPa in compression and 20 MPa in tension. The relief anomalies of the Tharsis volcanic plateau and symmetric feature in the eastern hemisphere could have arisen and been maintained dynamically due to two plumes in the mantle substance that are enriched with fluids. The plumes that originate at the core of Mars can arise and be maintained by the anomalies of the inner gravitational field achieving +800 mGal in the region of plume formation, - 1200 mGal above the lower mantle-core transition layer, and -1400 mGal at the crust.
Membrane Paradigm, Gravitational $\\Theta$-Term and Gauge/Gravity Duality
Fischler, Willy
2015-01-01
Following the membrane paradigm, we explore the effect of the gravitational $\\Theta$-term on the behavior of the stretched horizon of a black hole in (3+1)-dimensions. We reformulate the membrane paradigm from a quantum path-integral point of view where we interpret the macroscopic properties of the horizon as effects of integrating out the region inside the horizon. The gravitational $\\Theta$-term is a total derivative, however, using our framework we show that this term affects the transport properties of the horizon. In particular, the horizon acquires a third order parity violating, dimensionless transport coefficient which affects the way localized perturbations scramble on the horizon. Then we consider a large-N gauge theory in (2+1)-dimensions which is dual to an asymptotically AdS background in (3+1)-dimensional spacetime to show that the $\\Theta$-term induces a non-trivial contact term in the energy-momentum tensor of the dual theory. As a consequence, the dual gauge theory in the presence of the $\\T...
Gravitational Energy for GR and Poincare Gauge Theories: a Covariant Hamiltonian Approach
Chen, Chiang-Mei; Tung, Roh-Suan
2015-01-01
Our topic concerns a long standing puzzle: the energy of gravitating systems. More precisely we want to consider, for gravitating systems, how to best describe energy-momentum and angular momentum/center-of-mass momentum (CoMM). It is known that these quantities cannot be given by a local density. The modern understanding is that (i) they are quasi-local (associated with a closed 2-surface), (ii) they have no unique formula, (iii) they have no reference frame independent description. In the first part of this work we review some early history, much of it not so well known, on the subject of gravitational energy in Einstein's general relativity (GR), noting especially Noether's contribution. In the second part we review (including some new results) much of our covariant Hamiltonian formalism and apply it to Poincar\\'e gauge theories (GR is a special case). The key point is that the Hamiltonian boundary term has two roles, it determines the quasi-local quantities, and, furthermore it determines the boundary con...
Hawking Radiation of Black Rings from Anomalies
Chen, Bin; He, Wei
2007-01-01
We derive Hawking radiation of 5-dimensional black rings from gauge and gravitational anomalies using the method proposed by Robinson and Wilczek. We find as in the black hole case, the problem could reduce to a (1+1) dimensional field theory and the anomalies result in correct Hawking temperature for neutral,dipole and charged black rings.
Bashinsky, Sergei
2015-01-01
We study a finite basic structure that possibly underlies the observed elementary quantum fields with gauge and gravitational interactions. Realistic wave functions of locally interacting quantum fields emerge naturally as fitting functions for the generic distribution of many quantifiable properties of arbitrary static objects. We prove that in any quantum theory with the superposition principle, evolution of a current state of fields unavoidably continues along alternate routes with every conceivable Hamiltonian for the fields. This applies to the emergent quantum fields too. Yet the Hamiltonian is unambiguous for isolated emergent systems with sufficient local symmetry. The other emergent systems, without specific physical laws, cannot be inhabitable. The acceptable systems are eternally inflating universes with reheated regions. We see how eternal inflation perpetually creates new short-scale physical degrees of freedom and why they are initially in the ground state. In the emergent quantum worlds probabi...
Classical field theory on electrodynamics, non-Abelian gauge theories and gravitation
Scheck, Florian
2012-01-01
The book describes Maxwell's equations first in their integral, directly testable form, then moves on to their local formulation. The first two chapters cover all essential properties of Maxwell's equations, including their symmetries and their covariance in a modern notation. Chapter 3 is devoted to Maxwell theory as a classical field theory and to solutions of the wave equation. Chapter 4 deals with important applications of Maxwell theory. It includes topical subjects such as metamaterials with negative refraction index and solutions of Helmholtz' equation in paraxial approximation relevant for the description of laser beams. Chapter 5 describes non-Abelian gauge theories from a classical, geometric point of view, in analogy to Maxwell theory as a prototype, and culminates in an application to the U(2) theory relevant for electroweak interactions. The last chapter 6 gives a concise summary of semi-Riemannian geometry as the framework for the classical field theory of gravitation. The chapter concludes wit...
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The dynamics of metric perturbations is explored in the gravity theory with anomaly-induced quantum corrections. Our first purpose is to derive the equation for gravitational waves in this theory on the general homogeneous and isotropic background, and then verify the stability of such background with respect to metric perturbations. The problem under consideration has several interesting applications. Our first purpose is to explore the stability of the classical cosmological solutions in the theory with quantum effects taken into account. There is an interesting literature about stability of Minkowski and de Sitter spaces and here we extend the consideration also to the radiation and matter dominated cosmologies. Furthermore, we analyze the behavior of metric perturbations during inflationary period, in the stable phase of the Modified Starobinsky inflation
Stress-tensor trace anomaly in a gravitational metric: Scalar fields
International Nuclear Information System (INIS)
We compute the stress-tensor vacuum expectation value of a massive, scalar quantum field that is coupled to the metric of an arbitrary classical gravitational field. The renormalized tensor is defined by a dimensionally continued, proper-time representation. The stress tensor is calculated for arbitrary dimension in a potentially conformal-invariant manner so that its trace is formally proportional to the square of the scalar-field mass with this trace vanishing as the scalar field becomes massless. However, the renormalized stress tensor violates this formal identity with its trace containing additional, anomalous terms. These finite-trace anomalies are intimately related to the infinite counterterms that must be put into the action to make the stress tensor finite
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A striking consequence of supersymmetry breaking communicated purely via the superconformal anomaly is that the gaugino masses are proportional to the gauge ? functions. This result, however, is not unique to anomaly mediation. We present examples of ''generalized'' gauge-mediated models with messengers in standard model representations that give nearly identical predictions for the gaugino masses, but positive (mass)2 for all sleptons. There are remarkable similarities between an anomaly-mediated model with a small additional universal mass added to all scalars and the gauge-mediated models with a long-lived W-ino next-to-lightest supersymmetric particle, leading to only a small set of observables that provide robust distinguishing criteria. These include ratios of the heaviest to lightest selectrons, smuons, and top squarks. The sign of the gluino soft mass is an unambiguous distinction, but requires measuring a difficult class of one-loop radiative corrections to sparticle interactions. A high precision measurement of the Higgs-boson-b-b(bar sign) coupling is probably the most promising interaction from which this sign might be extracted. (c) 2000 The American Physical Society
Structure crustale et anomalies du champ de gravite dans l'est du Canada
Telmat, Hamid
Cette these presente les resultats d'etudes gravimetriques menees dans le Bouclier canadien. Les mesures du champ de gravite recoltees le long et a proximite de divers transects Lithoprobe y sont interpretees. Chacun des chapitres de cette these est un article publie ou soumis. Le premier article presente l'interpretation gravimetrique le long de la ligne sismique 52 de Lithoprobe, dans la province de Grenville. A l'echelle regionale, la modelisation de l'anomalie de Bouguer invoque un amincissement crustal au sud du front de Grenville sous le terrane allochtone du reservoir Cabonga. Cet amincissement, localise au niveau de la croute inferieure, peut etre associe a une extension post-orogenique. Le modele gravimetrique a aussi permis de mettre en evidence des caracteristiques majeures non revelees par les donnees sismiques, telle que la zone de contact subverticale entre les terranes du reservoir de Cabonga et du reservoir Dozois. La rampe de Baskatong representerait une discontinuite majeure le long de laquelle, les terranes proterozoiques furent accretes. Par ailleurs, un modele de l'anomalie residuelle, dans la partie nord du profil, met en evidence trois corps gabbroiques peu profonds. Le second article presente des modeles crustaux du nord de la province du Superieur a la lumiere de nouvelles donnees de gravite recoltees le long d'un transect traversant les sous-provinces de Nemiscau et La Grande. L'interpretation de l'anomalie de Bouguer pour le nord de l'Abitibi et l'Opatica, invoque un epaississement crustal. Pour les sous-provinces de Nemiscau et La Grande, l'interpretation gravimetrique invoque une densite de la croute superieure plus elevee qu'en Abitibi et en Opatica. Un leger epaississement crustal est observe dans la sous-province de La Grande. Des sequences supracrustales mafiques sont aussi mises en evidence a l'extremite nord du profil dans la sous-province de La Grande. La signature gravimetrique associee a la variation laterale de densite et les evidences de terrain indiquent un pendage vers le nord des principales frontieres tectoniques. Le troisieme chapitre fait l'objet d'une etude du champ de pesanteur au dessus de la region de la baie d'Ungava a partir de donnees satellite et de nouvelles donnees recoltees le long de la cote sud de la baie. Un leve gravimetrique partant de la baie aux Feuilles, dans la province du Superieur, traversant l'Orogene du Nouveau Quebec (ONQ), et finissant pres de la riviere George dans le craton de Rae, a ete realise. L'interpretation des donnees acquises a permis de fournir des modeles de densite. Ces modeles mettent en evidence un epaississement crustal sous l'ONQ et un amincissement sous le terrane de Kuujjuaq, a l'est de l'orogene. Alors que plus a l'est, dans le craton de Rae, une anomalie negative de quelques dix milligals est correlee avec les extensions vers le nord de la zone de cisaillement de la riviere George (ZCRG) et du batholite de De Pas. L'orientation des structures sur les modeles de gravite suggere un chevauchement du craton de Rae au dessus de l'ONQ. (Abstract shortened by UMI.)
Online-Offline, 1999
1999-01-01
This theme issue on anomalies includes Web sites, CD-ROMs and software, videos, books, and additional resources for elementary and junior high school students. Pertinent activities are suggested, and sidebars discuss UFOs, animal anomalies, and anomalies from nature; and resources covering unexplained phenonmenas like crop circles, Easter Island,…
Brizuela, David; Kraemer, Manuel
2015-01-01
We present detailed calculations for quantum-gravitational corrections to the power spectra of gauge-invariant scalar and tensor perturbations during inflation. This is done by performing a semiclassical Born--Oppenheimer type of approximation to the Wheeler--DeWitt equation, from which we obtain a Schr\\"odinger equation with quantum-gravitational correction terms. As a first step, we perform our calculation for a de Sitter universe and find that the correction terms lead to an enhancement of power on the largest scales.
Osburn, Thomas; Evans, Charles; Hopper, Seth
2014-01-01
We present an algorithm for calculating the metric perturbations and gravitational self-force for extreme-mass-ratio inspirals (EMRIs) with eccentric orbits. The massive black hole is taken to be Schwarzschild and metric perturbations are computed in Lorenz gauge. The perturbation equations are solved as coupled systems of ordinary differential equations in the frequency domain. Accurate local behavior of the metric is attained through use of the method of extended homogeneous solutions and mode-sum regularization is used to find the self-force. We focus on calculating the self-force with sufficient accuracy to ensure its error contributions to the phase in a long term orbital evolution will be $\\delta\\Phi \\lesssim 10^{-2}$ radians. This requires the orbit-averaged force to have fractional errors $\\lesssim 10^{-8}$ and the oscillatory part of the self-force to have errors $\\lesssim 10^{-3}$ (a level frequently easily exceeded). Our code meets this error requirement in the oscillatory part, extending the reach...
Classical field theory. On electrodynamics, non-Abelian gauge theories and gravitation
Energy Technology Data Exchange (ETDEWEB)
Scheck, Florian [Mainz Univ. (Germany)
2012-07-01
The book describes Maxwell's equations first in their integral, directly testable form, then moves on to their local formulation. The first two chapters cover all essential properties of Maxwell's equations, including their symmetries and their covariance in a modern notation. Chapter 3 is devoted to Maxwell theory as a classical field theory and to solutions of the wave equation. Chapter 4 deals with important applications of Maxwell theory. It includes topical subjects such as metamaterials with negative refraction index and solutions of Helmholtz' equation in paraxial approximation relevant for the description of laser beams. Chapter 5 describes non-Abelian gauge theories from a classical, geometric point of view, in analogy to Maxwell theory as a prototype, and culminates in an application to the U(2) theory relevant for electroweak interactions. The last chapter 6 gives a concise summary of semi-Riemannian geometry as the framework for the classical field theory of gravitation. The chapter concludes with a discussion of the Schwarzschild solution of Einstein's equations and the classical tests of general relativity (perihelion precession of Mercury, and light deflection by the sun).
On the definition of gauge transformations in gauge theory
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The different types of gauge transformations in gauge theory are discerned and defined in fiber bundle terms. The gauge gravitation case is analysed in order to examine various versions of the gauge gravitation theory. (author)
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We extend a previous analysis on the derivation of the dilaton Wess–Zumino (WZ) action in d = 4, based on the method of Weyl gauging, to six dimensions. As in the previous case, we discuss the structure of the same action in dimensional regularization using six-dimensional Weyl invariants, extracting the dilaton interactions in the most general scheme, with the inclusion of the local anomaly terms. As an application, we present the WZ action for the (2,0) tensor multiplet, which has been investigated in the past in the context of the AdS7/CFT6 holographic anomaly matching. We then extend to d = 6 the investigation of fully traced correlation functions of energy–momentum tensor’s, formerly presented in d = 4, showing that their hierarchy is functionally related only to the first six correlators. We give the explicit expressions of these in the most general scheme, up to rank-4. (paper)
Buchbinder, I L; Pershin, V D; Buchbinder, I L; Mistchuk, B R; Pershin, V D
1995-01-01
The general BRST-BFV analysis of anomaly in the string theory coupled to background fields is carried out. An exact equation for c-valued symbol of anomaly operator is found and structure of its solutions is studied.
Holomorphy, Rescaling Anomalies and Exact $\\beta$ Functions in Supersymmetric Gauge Theories
Arkani-Hamed, N; Arkani-Hamed, Nima; Murayama, Hitoshi
2000-01-01
There have been known "exact" beta functions for the gauge coupling in N=1 supersymmetric gauge theories, the so-called NSVZ beta functions. Shifman and Vainshtein (SV) further related these beta functions to the exact 1-loop running of the "Wilsonian" gauge coupling. All these results, however, remain somewhat mysterious. We attempt to clarify these issues by presenting new perspectives on the NSVZ beta function. Our interpretation of the results is somewhat different than the one given by SV, having nothing to do with the distinction between "Wilsonian" and "1PI" effective actions. Throughout we work in the context of the Wilsonian Renormalization Group; namely, as the cutoff of the theory is changed from M to M', we determine the appropriate changes in the bare couplings needed to keep the low energy physics fixed. The entire analysis is therefore free of infrared subtleties. When the bare Lagrangian given at the cutoff is manifestly holomorphic in the gauge coupling, we show that the required change in th...
International Nuclear Information System (INIS)
A theory of gravitation in more than four dimensions (Kaluza-Klein theory) is considered to see if it can explain in a natural, unified way the observed gauge and gravitational fields in four dimensions. The extra dimensions are taken to be closed and small enough that they cannot be observed directly. The possibility that quantum effects might cause the contraction of the extra dimensions is considered. The quantum effective potential (Casimir energy) of the gravitational field is calculated on the space-time manifold (Minkowski-space)x(N-sphere) to one-loop order in the loop expansion. (N must be odd for technical reasons). A cosmological constant is included in the higher dimensional theory, although the observed cosmological constant in four dimensions is required to be zero. For positive values of the cosmological constant the effective potential is attractive, which means that the extra dimensions would tend to contract at least until they are of a size on the order of the Planck length. The minima of the effective potential, which determine the solutions to the quantum-corrected equations of motion, are located. The first case in which a solution meeting certain minimal requirements is found is N = 13, in which case the associated gauge group is SO(14). The gauge coupling constant in this theory is a predicted number. Similar solutions are found for N = 15, 17, 19, and 21. Unfortunately, in all cases the effective potential has an imaginary part, which is interpreted as an instability of the solution against quantum decay
Locally covariant chiral fermions and anomalies
Zahn, Jochen
2015-01-01
We define chiral fermions in the presence of non-trivial gravitational and gauge background fields in the framework of locally covariant field theory. This allows to straightforwardly compute the chiral anomalies on non-compact Lorentzian spacetimes, without recourse to a weak field approximation.
Locally covariant chiral fermions and anomalies
Zahn, Jochen
2015-01-01
We define chiral fermions in the presence of non-trivial gravitational and gauge background fields in the framework of locally covariant field theory. This allows to straightforwardly compute the chiral anomalies on non-compact Lorentzian space-times, without recourse to a weak field approximation.
Anomaly cancellation in M-theory
de Alwis, S P
1997-01-01
We show the complete cancellation of gauge and gravitational anomalies in the M-theory of Horava and Witten using their boundary contribution, and a term coming from the existence of two and five-branes. A factor of three discrepancy noted in an earlier work is resolved. We end with a comment on flux quantization.
Locally covariant chiral fermions and anomalies
Directory of Open Access Journals (Sweden)
Jochen Zahn
2015-01-01
Full Text Available We define chiral fermions in the presence of non-trivial gravitational and gauge background fields in the framework of locally covariant field theory. This allows to straightforwardly compute the chiral anomalies on non-compact Lorentzian spacetimes, without recourse to a weak field approximation.
International Nuclear Information System (INIS)
This book is a populary introduction to the current status of research in gravitation. After a description of the gravitational theory of Newton and Einstein's general relativity theory the quantum theory of gravitation and supergravity are introduced. Then the dimensions of the space-time are discussed. Thereafter gravitational waves and gravitational lenses are described. Finally black holes, cosmic jets, and the structure of the universe are considered. (HSI)
Covariant Lorentz anomalies in higher dimensional space
International Nuclear Information System (INIS)
The covariant Lorentz anomalies are evaluated by both the path integral and the topological methods, when Weyl fermions couple with the gauge and gravitational fields. In 2,4,6-dimensional curved space, the difference between the results obtained by the two methods is removed by counterterms and the equivalence of both methods is proved. It is shown that the Lorentz anomalies in flat space of arbitrary dimensions are eliminated. (author)
Iorio, L
2006-01-01
In this paper we put on the test the new mechanism of gravitational origin recently put forth by Jaekel and Reynaud in order to explain the Pioneer anomaly in the framework of their post-Einsteinian metric extension of general relativity. According to such a proposal, the secular part of the anomalous acceleration experienced by the twin spacecraft of about 1 nm s$^{-2}$ could be caused by an extra-potential \\delta\\Phi_P=c^2\\chi r^2, with \\chi=4 10^-8 AU^-2, coming from the second sector of the considered model. When applied to the motion of the planets of the Solar System, it would induce anomalous secular perihelion advances which amount to o tens-hundreds of arcseconds per century for the outer planets. As for other previously proposed non-conventional gravitational explanations of the Pioneer anomaly, the answer of the latest observational determinations of the residual perihelion rates by RAS IAA is neatly and unambiguously negative. The presence of another possible candidate to explain the Pioneer anoma...
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Stringent presentation of field theory, mediates the connection from the classicalelectrodynamics up to modern gauge theories. The compact presentation is ideal for the bachelor study. New chapter on general relativity theory. Deepens the learned by numerous application from laser physic, metamaterials and different more. Theoretical physics 3. Classical field theory. On electrodynamics, non-Abelian, and gravitation is the third of five volumes on theoretical physics by professor Scheck. The cycle theoretical physics comprehends: Volume 1: Mechanics. From Newtons law to the deterministic chaos. Volume 2: Nonrelativistic quantum theory. From the hydrogen atom to the many-particle systems. Volume 3: Classical field theory. From the electrodynamics to the gauge theories. Volume 5: From the laws of thermodynamics to the quantum statistics. This textbook mediates modern theoretical physics in string presentation illustrated by many examples. It contains numerous problems with solution hints ore exemplary, complete solutions. The third edition was revised in many single topics, especially the chapter on general relativity theory was supplemented by an extensive analysis of the Schwarzschild solution.
A Nonperturbative Regulator for Chiral Gauge Theories
Grabowska, Dorota M
2015-01-01
We propose a nonperturbative gauge invariant regulator for $d$-dimensional chiral gauge theories on the lattice. The method involves simulating domain wall fermions in $d+1$ dimensions with quantum gauge fields that reside on one $d$-dimensional surface and are extended into the bulk via gradient flow. The result is a theory of gauged fermions plus mirror fermions, where the mirror fermions couple to the gauge fields via a form factor that becomes exponentially soft with the separation between domain walls. The resultant theory has a local $d$-dimensional interpretation if and only if the chiral fermion representation is anomaly free. A physical realization of this construction leads to mirror fermions in the Standard Model with soft form factors for gauge fields and gravity. These mirror particles could evade detection except by sensitive probes at extremely low energy, and yet still affect vacuum topology, and could gravitate differently than conventional matter.
Stress-tensor trace anomaly in a gravitational metric: General theory, Maxwell field
International Nuclear Information System (INIS)
The renormalization of the vacuum expectation value of the stress-energy tensor of a scalar field propagating in a curved space-time with an arbitrary metric was discussed in a previous paper. A new regularization scheme was introduced which employs a continuation in the dimensionality of space-time implemented with a proper-time representation of the Green's function. Here we present a more general formulation of this method which clarifies its basic features and which explicitly displays the stress tensor as the metric functional derivative of the one-loop action functional. We apply this more general formulation to both the scalar field theory and to the electrodynamic, Maxwell theory. Although the trace of the stress tensor formally vanishes both for the massless scalar field and for the Maxwell field, the trace of the renormalized vacuum expectation value of the stress tensor does not vanish for either theory. These finite-trace anomalies cannot be removed by adding a finite local counterterm into the Lagrange function. The anomalies are intimately related to the infinite scalar counterterms that are needed to render the action finite
Anomalies of the Entanglement Entropy in Chiral Theories
Iqbal, Nabil
2015-01-01
We study entanglement entropy in theories with gravitational or mixed U(1) gauge-gravitational anomalies in two, four and six dimensions. In such theories there is an anomaly in the entanglement entropy: it depends on the choice of reference frame in which the theory is regulated. We discuss subtleties regarding regulators and entanglement entropies in anomalous theories. We then study the entanglement entropy of free chiral fermions and self-dual bosons and show that in sufficiently symmetric situations this entanglement anomaly comes from an imbalance in the flux of modes flowing through the boundary, controlled by familiar index theorems. In two and four dimensions we use anomalous Ward identities to find general expressions for the transformation of the entanglement entropy under a diffeomorphism. (In the case of a mixed anomaly there is an alternative presentation of the theory in which the entanglement entropy is not invariant under a U(1) gauge transformation. The free-field manifestation of this pheno...
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We show that the Implicit Regularization Technique is useful to display quantum symmetry breaking in a complete regularization independent fashion. Arbitrary parameters are expressed by finite differences between integrals of the same superficial degree of divergence whose value is fixed on physical grounds (symmetry requirements or phenomenology). We study Weyl fermions on a classical gravitational background in two dimensions and show that, assuming Lorentz symmetry, the Weyl and Einstein Ward identities reduce to a set of algebraic equations for the arbitrary parameters which allows us to study the Ward identities on equal footing. We conclude in a renormalization independent way that the axial part of the Einstein Ward identity is always violated. Moreover whereas we can preserve the pure tensor part of the Einstein Ward identity at the expense of violating the Weyl Ward identities we may as well violate the former and preserve the latter
An anomaly-free model in six dimensions
International Nuclear Information System (INIS)
We show that a gauged supergravity theory based on E6xE7xU(1) is free of gauge and gravitational anomalies in six dimensions. It compactifies to (Minkowski)4xS2 by the standard monopole mechanism. With a monopole of strength n in E6, the resulting four-dimensional theory exhibits chiral SO(10)xU(1) with 2|n| families (and no antifamilies). Supersymmetry is broken. (author)
Note on Anomaly Cancellation on SO(32) heterotic 5-brane
Imazato, Harunobu; Yata, Masaya
2010-01-01
We show that the gauge, gravitational (tangent-bundle) and their mixed anomalies arising from the localized modes near a 5-brane in the SO(32) heterotic string theory cancel with the anomaly inflow from the bulk with the use of Green-Schwarz mechanism on the brane, similarly to the E_8 x E_8 5-brane case. We also compare our result with Mourad's analysis performed in the small-instanton limit.
Interpretation of a short-term anomaly in the gravitational microlensing event MOA-2012-BLG-486
Energy Technology Data Exchange (ETDEWEB)
Hwang, K.-H.; Choi, J.-Y.; Han, C. [Department of Physics, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Bond, I. A. [Institute of Information and Mathematical Sciences, Massey University, Private Bag 102-904, North Shore Mail Centre, Auckland (New Zealand); Sumi, T.; Koshimoto, N. [Department of Earth and Space Science, Osaka University, Osaka 560-0043 (Japan); Gaudi, B. S.; Gould, A. [Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Bozza, V. [Dipartimento di Fisica " E. R. Caianiello," Università degli Studi di Salerno, Via S. Allende, I-84081 Baronissi (Italy); Beaulieu, J.-P. [UPMC-CNRS, UMR7095, Institut d' Astrophysique de Paris, 98bis boulevard Arago, F-75014 Paris (France); Tsapras, Y. [Las Cumbres Observatory Global Telescope Network, 6740B Cortona Dr, Goleta, CA 93117 (United States); Abe, F.; Fukunaga, D.; Itow, Y. [Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya 464-8601 (Japan); Bennett, D. P. [Department of Physics, University of Notre Dame, 225 Nieuwland Science Hall, Notre Dame, IN 46556-5670 (United States); Botzler, C. S.; Freeman, M. [Department of Physics, University of Auckland, Private Bag 92-019, Auckland 1001 (New Zealand); Chote, P.; Harris, P. [School of Chemical and Physical Sciences, Victoria University, Wellington (New Zealand); Fukui, A. [Okayama Astrophysical Observatory, National Astronomical Observatory of Japan, Asakuchi, Okayama 719-0232 (Japan); Collaboration: MOA Collaboration; ?FUN Collaboration; PLANET Collaboration; RoboNet Collaboration; and others
2013-11-20
A planetary microlensing signal is generally characterized by a short-term perturbation to the standard single lensing light curve. A subset of binary-source events can produce perturbations that mimic planetary signals, thereby introducing an ambiguity between the planetary and binary-source interpretations. In this paper, we present the analysis of the microlensing event MOA-2012-BLG-486, for which the light curve exhibits a short-lived perturbation. Routine modeling not considering data taken in different passbands yields a best-fit planetary model that is slightly preferred over the best-fit binary-source model. However, when allowed for a change in the color during the perturbation, we find that the binary-source model yields a significantly better fit and thus the degeneracy is clearly resolved. This event not only signifies the importance of considering various interpretations of short-term anomalies, but also demonstrates the importance of multi-band data for checking the possibility of false-positive planetary signals.
International Nuclear Information System (INIS)
High-frequency gravitational waves considered as ''ripples'' of a given background are a perturbation of the type h/sub munu/(chi/sup ?/,?phi), where phi is a smooth phase function and ? a large parameter (frequency). In a general Bianchi IX model, the h/sub munu/ are expanded in Wigner D/sup j//sub mn/ functions and the time-dependent expansion coefficients appear in the dynamical equations in mixed form. I investigated the dependence of the propagation and back-reaction equations on the quantum number j and performed an asymptotic analysis for large j-values on the eigen modes h/sup m//sub i//sub j/. When the expansion of the principal axes a/sub i/ decreases, the equations for h/sup m//sub i//sub j/ are uncoupled and the frequency is approximately 2[E(l1l1l3)]/sup 1/2/, where E(l1l1l3) is the eigenvalue of the Hamiltonian of a symmetrical top and l/sub i/ the inverse of a/sub i/. The back-reaction can be cast in a perfect fluid, by integrating the equations over a period of the high-frequency field. When, however, the three principal Hubble parameters a/sub i//a/sub i/ are large, the equations can be numerically integrated. Further, a gauge-invariant density perturbation is constructed
International Nuclear Information System (INIS)
The perturbation theory in coset pure gauge field theory is studied for the first time. By using the Bjorken-johnson-Low technique and calculating the Schwinger term in related commutators, the anomalous Ward identity in Abelian coset pure gauge field theory is derived, which is consistent with the non-perutrbative calculation
International Nuclear Information System (INIS)
The lectures given cover the topological effects in gauge field theories, fermionic chiral anomalies, and some relationships between the two. Gauge field theories in three and four space-time dimensions are considered. Topological terms as external U(1) functional gauge potential connections in field space are discussed. Both the structure and physical impact of anomalies are described. 17 refs
Elsayed, Ahmed Mohammed Hussain El Kenawy
2015-05-01
Many arid and semi-arid regions have sparse precipitation observing networks, which limits the capacity for detailed hydrological modelling, water resources management and flood forecasting efforts. The objective of this work is to evaluate the utility of relatively high-spatial resolution rainfall products to reproduce observed multi-decadal rainfall characteristics such as climatologies, anomalies and trends over Saudi Arabia. Our study compares the statistical characteristics of rainfall from 53 observatories over the reference period 1965-2005, with rainfall data from six widely used gauge-based products, including APHRODITE, GPCC, PRINCETON, UDEL, CRU and PREC/L. In addition, the performance of three global climate models (GCMs), including CCSM4, EC-EARTH and MRI-I-CGCM3, integrated as part of the Fifth Coupled Model Intercomparison Project (CMIP5), was also evaluated. Results indicate that the gauge-based products were generally skillful in reproducing rainfall characteristics in Saudi Arabia. In most cases, the gauge-based products were also able to capture the annual cycle, anomalies and climatologies of observed data, although significant inter-product variability was observed, depending on the assessment metric being used. In comparison, the GCM-based products generally exhibited poor performance, with larger biases and very weak correlations, particularly during the summertime. Importantly, all products generally failed to reproduce the observed long-term seasonal and annual trends in the region, particularly during the dry seasons (summer and autumn). Overall, this work suggests that selected gauge-based products with daily (APHRODITE and PRINCETON) and monthly (GPCC and CRU) resolutions show superior performance relative to other products, implying that they may be the most appropriate data source from which multi-decadal variations of rainfall can be investigated at the regional scale over Saudi Arabia. Discriminating these skillful products is important not only for reducing uncertainty in climate, hydrological and environmental assessments but also for advancing model developments in the region. Â© 2015 Royal Meteorological Society.
More on axial anomalies of Lifshitz fermions
Bakas, Ioannis
2011-01-01
We show that the gauge and metric field contribution to the axial anomaly of a four-dimensional massless Lifshitz fermion theory with anisotropy scaling exponent z is identical to the relativistic case, hereby extending the results found in arXiv:1103.5693 to arbitrary values of z. This is in accordance with the fact that the axial anomaly is an infra-red phenomenon in disguise. We also provide some new models that realize baryon and lepton number violation in non-relativistic theories of gravity. In all cases, the volume of space exhibits a lower bound that is fixed by the gravitational coupling parameters.
Search for light massive gauge bosons as an explanation of the $(g-2)_\\mu$ anomaly at MAMI
Merkel, H; Gayoso, C Ayerbe; Beranek, T; Beri?i?, J; Bernauer, J C; Böhm, R; Bosnar, D; Correa, L; Debenjak, L; Denig, A; Distler, M O; Esser, A; Fonvieille, H; Friš?i?, I; de la Paz, M Gómez Rodríguez; Hoek, M; Kegel, S; Kohl, Y; Middleton, D G; Mihovilovi?, M; Müller, U; Nungesser, L; Pochodzalla, J; Rohrbeck, M; Ron, G; Majos, S Sánchez; Schlimme, B S; Schoth, M; Schulz, F; Sfienti, C; Širca, S; Thiel, M; Tyukin, A; Weber, A; Weinriefer, M
2014-01-01
A massive, but light abelian U(1) gauge boson is a well motivated possible signature of physics beyond the Standard Model of particle physics. In this paper, the search for the signal of such a U(1) gauge boson in electron-positron pair-production at the spectrometer setup of the A1 Collaboration at the Mainz Microtron (MAMI) is described. Exclusion limits in the mass range of 40 MeV up to 300 MeV with a sensitivity in the mixing parameter of down to $\\epsilon^2 = 8\\times 10^{-7}$ are presented. A large fraction of the parameter space has been excluded where the discrepancy of the measured anomalous magnetic moment of the muon with theory might be explained by an additional U(1) gauge boson.
Without gravity, you would float into space. Gravity pulls matter together: it holds us onto the Earth, it holds the Earth in orbit around the sun and it holds our solar system in orbit about the centre of the galaxy. Everything with mass feels the attraction of gravity. The strength of the attraction between 2 objects depends on their masses. Despite its omnipresence, gravity is the weakest of the 4 forces. It is insignificant at the scale of human beings: when a group of visitors walks past, gravity doesn't pull you towards them! At even smaller scales, the gravitational pull between the electron and the proton is about 1040 times weaker than the electromagnetic attraction between them. Text for the interactive: Why does the same mass weigh more on the Earth than on the moon ?
Anomalies in M-theory on singular G2-manifolds
International Nuclear Information System (INIS)
When M-theory is compactified on G2-holonomy manifolds with conical singularities, charged chiral fermions are present and the low-energy four-dimensional theory is potentially anomalous. We reconsider the issue of anomaly cancellation, first studied by Witten. We propose a mechanism that provides local cancellation of all gauge and mixed gauge-gravitational anomalies, i.e., separately for each conical singularity. It is similar in spirit to the one used to cancel the normal bundle anomaly in the presence of five-branes. It involves smoothly cutting off all fields close to the conical singularities, resulting in an anomalous variation of the 3-form C and of the non-abelian gauge fields present if there are also ADE singularities
Galilean Anomalies and Their Effect on Hydrodynamics
Jain, Akash
2015-01-01
We extend the null background construction of [arXiv:1505.05677,arXiv:1509.04718] to include torsion and a conserved spin current, and use it to study gauge and gravitational anomalies in Galilean theories coupled to torsional Newton-Cartan backgrounds. We establish that the relativistic anomaly inflow mechanism with an appropriately modified anomaly polynomial, can be used to generate these anomalies. Similar to relativistic case, we find that Galilean anomalies also survive only in even dimensions. Further, these anomalies only effect the gauge and rotational symmetries of a Galilean theory; in particular the Milne boost symmetry remains non-anomalous. We also extend the transgression machinery used in relativistic fluids to fluids on null backgrounds, and use it to determine how these anomalies affect the constitutive relations of a Galilean fluid. Unrelated to Galilean fluids, we propose an analogue of the off-shell second law of thermodynamics for relativistic fluids introduced by [arXiv:1106.0277], to i...
Energy Technology Data Exchange (ETDEWEB)
Gripaios, Ben [Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Rd., Oxford OX1 3NP (United Kingdom); Merton College, Oxford OX1 4JD (United Kingdom)], E-mail: b.gripaios1@physics.ox.ac.uk; West, Stephen M. [Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Rd., Oxford OX1 3NP (United Kingdom)], E-mail: s.west1@physics.ox.ac.uk
2008-01-21
We consider, in the effective field theory context, anomalies of gauge field theories on a slice of a five-dimensional, anti-de Sitter geometry and their four-dimensional, holographic duals. A consistent effective field theory description can always be found, notwithstanding the presence of the anomalies and without modifying the degrees of freedom of the theory. If anomalies do not vanish, the d=4 theory contains additional pseudoscalar states, which are either present in the low-energy theory as physical, light states, or are eaten by (would-be massless) gauge bosons. We show that the pseudoscalars ensure that global anomalies of the four-dimensional dual satisfy the 't Hooft matching condition and comment on the relevance for warped models of electroweak symmetry breaking.
Path integral quantization of gravitational interactions
International Nuclear Information System (INIS)
Some of the local symmetry properties of quantum field theory in curved space-time and quantized gravitational interactions are discussed. We concentrate on local symmetry properties, and thus the asymptotically flat space-time is assumed, whenever necessary, in the hope that the precise boundary conditions will not modify the short distance structure in quantum theory. We adopt the DeWitt-Faddeev-Popov prescription of the Feynman path integral with a complete gauge fixing. The topics discussed include: (i) A brief review of the path integral derivation of chiral anomalies in flat space-time. (ii) The specification of the gravitational path integral measure, which avoids all the ''fake'' gravitational anomalies, and the applications of this path integral prescription to 1) effective potential in generalized Kaluza-Klein theory, 2) 4-dimensional conformal anomalies, 3) conformal symmetry in pure conformal gravity, 4) bosonic string theory as a gravitational theory in d = 2, 5) Virasoro condition and the Wheeler-DeWitt equation in the path integral formalism, 6) gravitational anomalies and the definition of the energy-momentum tensor. (author)
Fisenko, S. I.
2001-01-01
Parity nonconservation in the beta-decay processes is considered as fundamental property of weak interactions. Nevertheless, this property can be treated as anomaly, because in fundamental interactions of the rest types parity is conserved. Analogously, anomaly in the short-duration strong-current pulse discharges is well known. The essence of this phenomenon consists in generation of local high-temperature plasma formations (LHTF) with the typical values of its thermodynami...
Trace anomalies from quantum mechanics
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The one-loop anomalies of a d-dimensional quantum field theory can be computed by evaluating the trace of the path integral jacobian matrix J, regulated by an operator exp(-?R) and taking the limit ? to zero. Sometime ago Alvarez-Gaume and Witten made the observation that one can simplify this evaluation by replacing the operators which appear in J and R by quantum mechanical operators with the same (anti)commutation relations. By rewriting this quantum mechanical trace as a path integral with periodic boundary conditions at time t=0 and t=? for a one-dimensional supersymmetric nonlinear sigma model, they obtained the chiral anomalies for spin-1/2 and spin-3/2 fields and selfdual antisymmetric tensors in d dimensions. One can also apply these ideas to the trace anomalies. Recently a bosonic configuration-space path integral for a particle moving in curved space was proposed by the first author, and the corresponding hamiltonian R was found from the Schroedinger equation. The factors ?g in the path-integral measure were exponentiated by using scalar ghosts, and the trace anomaly for a scalar field in an external gravitational field in d=2 was obtained. Here we treat the general case of trace anomalies for external gravitational and Yang-Mills fields. We do not introduce a supersymmetric sigma model, but keep the original Dirac matrices ?? and internal symmetry generators Ta in the path integral. As a result, we get a matrix-valued action S. Gauge covariance of the path integral then requires us to define the exponential of the action by time ordering. The computations are simplified by using Riemann normal coordinates. We also replace the scalar ghosts by vector ghosts in order to exhibit the cancellation of all divergences at finite ? more clearly. Finally we compute the trace anomalies in d=2 and d=4. (orig.)
Anomaly analysis of Hawking radiation from Kaluza-Klein black hole with squashed horizon
International Nuclear Information System (INIS)
Considering gravitational and gauge anomalies at the horizon, a new method to derive Hawking radiation from black holes has been developed by Wilczek et al. In this paper, we apply this method to non-rotating and rotating Kaluza-Klein black holes with squashed horizon, respectively. For the rotating case, we found that, after dimensional reduction, an effective U(1) gauge field is generated by an angular isometry. The results show that the gauge current and energy-momentum tensor fluxes are exactly equivalent to Hawking radiation from the event horizon. (orig.)
Renormalization of non-abelian gauge theories in curved space-time
International Nuclear Information System (INIS)
We use indirect, renormalization group arguments to calculate the gravitational counterterms needed to renormalize an interacting non-abelian gauge theory in curved space-time. This method makes it straightforward to calculate terms in the trace anomaly which first appear at high order in the coupling constant, some of which would need a 4-loop calculation to find directly. The role of gauge invariance in the theory is considered, and we discuss briefly the effect of using coordinate-dependent gauge-fixing terms. We conclude by suggesting possible applications of this work to models of the very early universe
Invariant Regularization of Supersymmetric Chiral Gauge Theory
Suzuki, Hiroshi(Department of Physics, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka, 812-8581, Japan)
1999-01-01
We present a regularization scheme which respects the supersymmetry and the maximal background gauge covariance in supersymmetric chiral gauge theories. When the anomaly cancellation condition is satisfied, the effective action in the superfield background field method automatically restores the gauge invariance without counterterms. The scheme also provides a background gauge covariant definition of composite operators that is especially useful in analyzing anomalies. We pr...
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We present an alternative field theoretical approach to the definition of conserved quantities, based directly on the field equation content of a Lagrangian theory (in the standard framework of the calculus of variations in jet bundles). The contraction of the Euler-Lagrange equations with Lie derivatives of the dynamical fields allows one to derive a variational Lagrangian for any given set of Lagrangian equations. A two-step algorithmical procedure can thence be applied to the variational Lagrangian in order to produce a general expression for the variation of all quantities which are (covariantly) conserved along the given dynamics. As a concrete example we test this new formalism on Einstein's equations: well-known and widely accepted formulae for the variation of the Hamiltonian and the variation of energy for general relativity are recovered. We also consider the Einstein-Cartan (Sciama-Kibble) theory in tetrad formalism and as a by-product we gain some new insight into the Kosmann lift in gauge natural theories, which arises when trying to restore naturality in a gauge natural variational Lagrangian
Compensating fields and anomalies
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In this article we shall examine the question of quantum equivalence in the presence of anomalies and review various results related to this issue. We will argue that anomalies do not affect the gauge-equivalence for theories with compensating fields. We discuss how intrinsic pathologies in models many reflect themselves in the extra terms required for gauge-equivalence, and the interplay between 'compensating anomalies' and anomalies in other invariances. We consider several examples: the (non-Abelian) Stueckelberg model, scale-invariant gravity, non-linear sigma models and supergravity. (author)
The Conformal Anomaly and the Neutral Currents Sector of the Standard Model
Coriano, Claudio; Quintavalle, Antonio; Serino, Mirko
2011-01-01
We elaborate on the structure of the graviton-gauge-gauge vertex in the electroweak theory, obtained by the insertion of the complete energy-momentum tensor ($T$) on 2-point functions of neutral gauge currents. The vertex defines the leading contribution to the effective action which accounts for the conformal anomaly and related interaction between the Standard Model and gravity. The energy momentum tensor is derived from the curved spacetime Lagrangian in the linearized gravitational limit, and with the inclusion of the term of improvement of a conformally coupled Higgs sector. The vertex is defined by a set of Ward and Slavnov-Taylor identities which are explicitly satisfied by the perturbative expansion in dimensional regularization. As in the previous cases of QED and QCD, we find that the conformal anomaly induces an effective massless pseudoscalar interaction between gravity and the neutral currents in each gauge invariant component of the vertex. We comment on the possible extension of similar analysi...
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Scheck, Florian [Mainz Univ. (Germany). Fachbereich Physik
2010-07-01
Stringent presentation of field theory, mediates the connection from the classicalelectrodynamics up to modern gauge theories. The compact presentation is ideal for the bachelor study. New chapter on general relativity theory. Deepens the learned by numerous application from laser physic, metamaterials and different more. Theoretical physics 3. Classical field theory. On electrodynamics, non-Abelian, and gravitation is the third of five volumes on theoretical physics by professor Scheck. The cycle theoretical physics comprehends: Volume 1: Mechanics. From Newtons law to the deterministic chaos. Volume 2: Nonrelativistic quantum theory. From the hydrogen atom to the many-particle systems. Volume 3: Classical field theory. From the electrodynamics to the gauge theories. Volume 5: From the laws of thermodynamics to the quantum statistics. This textbook mediates modern theoretical physics in string presentation illustrated by many examples. It contains numerous problems with solution hints ore exemplary, complete solutions. The third edition was revised in many single topics, especially the chapter on general relativity theory was supplemented by an extensive analysis of the Schwarzschild solution. [German] Stringente Darstellung der Feldtheorie, vermittelt den Zusammenhang von der klassischen Elektrodynamik bis zu modernen Eichtheorien. Die kompakte Darstellung ist ideal fuer das Bachelor-Studium. Neues Kapitel zur Allgemeinen Relativitaetstheorie. Vertieft das Erlernte durch zahlreiche Anwendungsbeispiele aus Laserphysik, Metamaterialien uvm. Theoretische Physik 3. Klassische Feldtheorie. Von Elektrodynamik, nicht-Abelschen Eichtheorien und Gravitation ist der dritte von fuenf Baenden zur Theoretischen Physik von Professor Scheck. Der Zyklus Theoretische Physik umfasst: Band 1: Mechanik. Von den Newtonschen Gesetzen zum deterministischen Chaos. Band 2: Nichtrelativistische Quantentheorie. Vom Wasserstoffatom zu den Vielteilchensystemen. Band 3: Klassische Feldtheorie. Von der Elektrodynamik zu den Eichtheorien Band 4: Quantisierte Felder. Von den Symmetrien zur Quantenelektrodynamik Band 5: Theorie der Waerme. Von den Hauptsaetzen der Thermodynamik zur Quantenstatistik Dieses Lehrbuch vermittelt moderne Theoretische Physik in stringenter, durch viele Beispiele illustrierter Darstellung. Es enthaelt zahlreiche Aufgaben mit Loesungshinweisen oder exemplarischen, vollstaendigen Loesungen. Die dritte Auflage wurde in vielen Einzelheiten ueberarbeitet, insbesondere das Kapitel ueber Allgemeine Relativitaetstheorie wurde um eine ausfuehrliche Analyse der Schwarzschild-Loesung ergaenzt. (orig.)
Lugo, A R
1992-01-01
Some remarks are made about free anomaly groups in gauged WZW models. Considering a quite general action, anomaly cancellation is analyzed. The possibility of gauging left and right sectors independently in some cases is remarked. In particular Toda theories can be seen as such a kind of models.
Holographic renormalization of cascading gauge theories
Aharony, O; Yarom, A; Aharony, Ofer; Buchel, Alex; Yarom, Amos
2005-01-01
We perform a holographic renormalization of cascading gauge theories. Specifically, we find the counter-terms that need to be added to the gravitational action of the backgrounds dual to the cascading theory of Klebanov and Tseytlin, compactified on an arbitrary four-manifold, in order to obtain finite correlation functions (with a limited set of sources). We show that it is possible to truncate the action for deformations of this background to a five dimensional system coupling together the metric and four scalar fields. Somewhat surprisingly, despite the fact that these theories involve an infinite number of high-energy degrees of freedom, we find finite answers for all one-point functions (including the conformal anomaly). We compute explicitly the renormalized stress tensor for the cascading gauge theories at high temperature and show how our finite answers are consistent with the infinite number of degrees of freedom. Finally, we discuss ambiguities appearing in the holographic renormalization we propose...
Anomaly-induced effective action and inflation
International Nuclear Information System (INIS)
In the early Universe matter can be described as a conformal invariant ultra-relativistic perfect fluid, which does not contribute, on classical level, to the evolution of the isotropic and homogeneous metric. If we suppose that there is some desert in the particle spectrum just below the Planck mass, then the effect of conformal trace anomaly is dominating at the corresponding energies. With some additional constraints on the particle content of the underlying gauge model (which favor extended or supersymmetric versions of the Standard Model rather than the minimal one), one arrives at the stable inflation. We review the model and report about the calculation of the gravitational waves on the background of the anomaly-induced inflation. The result for the perturbation spectrum is close to the one for the conventional inflation model, and is in agreement with the existing Cobe data
Trace anomalies from quantum mechanics
Bastianelli, F; Bastianelli, Fiorenzo; Nieuwenhuizen, Peter van
1993-01-01
The 1-loop anomalies of a d-dimensional quantum field theory can be computed by evaluating the trace of the regulated path integral jacobian matrix, as shown by Fujikawa. In 1983, Alvarez-Gaum\\'e and Witten observed that one can simplify this evaluation by replacing the operators which appear in the regulator and in the jacobian by quantum mechanical operators with the same (anti)commutation relations. By rewriting this quantum mechanical trace as a path integral with periodic boundary conditions for a one-dimensional supersymmetric nonlinear sigma model, they obtained the chiral anomalies for spin 1/2 and 3/2 fields and selfdual antisymmetric tensors in d dimensions. In this article, we treat the case of trace anomalies for spin 0, 1/2 and 1 fields in a gravitational and Yang-Mills background. We do not introduce a supersymmetric sigma model, but keep the original Dirac matrices $\\g^\\m$ and internal symmetry generators $T^a$ in the path integral. As a result, we get a matrix-valued action. Gauge covariance o...
Gravitational research. Gravitational waves
Amaldi, E.; Pizzella, G.
1985-04-01
Gravitational wave research is reviewed. Gravitational theory, relativity theory, experiments in general relativity, sources of gravitational waves, the Rome gravitational experiment, quantic limits of gravitational waves measurements and how to avoid those limits are discussed.
*-Wars episode I: the phantom anomaly
International Nuclear Information System (INIS)
As pointed out, chiral non-commutative theories exist, and examples can be constructed via string theory. Gauge anomalies require the matter content of individual gauge group factors, including U(1) factors, to be non-chiral. All 'bad' mixed gauge anomalies, and also all 'good' (e.g., for ?0???) ABJ type flavor anomalies, automatically vanish in non-commutative gauge theories. We interpret this as being analogous to string theory, and an example of UV/IR mixing: non-commutative gauge theories automatically contain 'closed string', Green-Schwarz fields, which cancel these anomalies
Anomalies in quantum field theory and differential geometry
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Anomalies in field theory appeared first in perturbative computations involving Feynman diagrams. It is only recently that differential geometric techniques have been used to obtain the form of gauge and gravitational anomalies in a direct and simple way. This is possible because of the topological nature of the anomaly. In the first chapter of this thesis the gauged Wess-Zumino action is constructed by differential geometry methods. After reviewing the relevant techniques, an expression for the action valid in any (even) number of space-time dimensions is obtained. This expression is compared with Witten's result in four dimensions. The link between topology and the anomaly is provided by the appropriate index theorem. The index density is a supersymmetric invariant polynomial from which the anomaly and other related objects can be obtained through the use of the ''descent equations.'' A new proof of the Atiyah-Singer index theorem for the Dirac operator is presented. This proof is based on the use of a WKB approximation to evaluate the supertrace of the kernel for a supersymmetric hamiltonian. The necessary WKB techniques are developed and mechanical systems with bosonic and fermionic degrees of freedom are discussed
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In the gauge proposed a large number of derivatives of the axial gravitational superfield Hsup(m) vanish at a given point in superspace. The remaining derivatives of Hsup(m) are the values at z0 of the basic superfields R, anti R, G, W, anti W in terms of which torsion and curvature are expressible. The normal gauge simplifies significantly many considerations and calculations in supergravity
Gravitation and electromagnetism
Sidharth, B. G.
2002-01-01
Maxwell's equations comprise both electromagnetic and gravitational fields. The transverse part of the vector potential belongs to magnetism, the longitudinal one is concerned with gravitation. The Coulomb gauge indicates that longitudinal components of the fields propagate instantaneously. The delta-function singularity of the field of the divergence of the vector potential, referred to as the dilatation center, represents an elementary agent of gravitation. Viewing a particle as a source or...
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Nonlocal gauge theories, including gravitation, are considered. It is shown that to give a meaning to ?5-anomalous theories it is sufficient to introduce an additional nonlocal interaction. The introduction of such an interaction leads to a unitary macrocausal theory describing the interaction of massive vector fields with fermion fields. It is shown that nonlocal gauge theories with nonlocality scale ?/sub nl/ ? (1-10) TeV are capable of solving the hierarchy problem. An example of a nonlinear gauge model of grand unification is found in which topologically nontrivial monopole solutions with finite energy are absent
More Anomalies from Fractional Branes
Bertolini, M.; Di Vecchia, P.; Frau, M; Lerda, A.(Università di Torino, Dipartimento di Fisica and INFN — Sezione di Torino, Via P. Giuria 1, I-10125, Torino, Italy); Marotta, R. (Rosanna)
2002-01-01
In this note we show how the anomalies of both pure and matter coupled N=1,2 supersymmetric gauge theories describing the low energy dynamics of fractional branes on orbifolds can be derived from supergravity.
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We develop a systematic method to construct the gauged BRST symmetry for any theory. In this framework, it results as the combination of two basic symmetries of the gauge-fixed theory one considers: the BRST symmetry and the ghost number symmetry, this later being promoted to a local one. From this, we can derive a general relation between the BRST and the ghost number Noether currents. We then take advantage of the present method to elaborate a geometrical algorithm leading to the obtention of the gauged BRST symmetry for a large class of theories, in arbitrary dimensions of space. These involve systems of antisymmetric tensor gauge fields of arbitrary rank, eventually coupled to gravity. This algorithm allows us to derive algebraically the expressions for the possible consistent anomalies of the BRST Noether current algebras; various examples are explicitely discussed. The gauged BRST symmetry for the free bosonic string is also constructed and used to exhibit the link between the trace anomaly and the nilpotency anomaly of the BRST charge operator. In particular, when the Beltrami parametrization is introduced, we show that the corresponding BRST symmetry can be gauged in a way compatible with the holomorphic factorization. A further use of Ward-Slavnov identities constraining the BRST and ghost number current algebra allows us to recover the well-known local counterterm necessary, at the one-loop level, to render the BRST current a good conformal operator
Charge, anomalies and index theory
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The author explains how gauge fields, spinor fields and other gauge-dependent quantities, are unobservable and are not primary, but are constructed from the properties of the observables. A brief survey is presented of the phenomenon of anomalies in theories with axial currents; some of the puzzling aspects of anomalies are described, such as the necessary breakdown of apparent symmetries of a theory, in the presence of external fields
Freund, Peter G. O.
2010-01-01
Erik Verlinde's proposal of the emergence of the gravitational force as an entropic force is extended to abelian and non-abelian gauge fields and to matter fields. This suggests a picture with no fundamental forces or forms of matter whatsoever.
Fundamental Forces as Gauge Theories
Roh, Heui-Seol
2001-01-01
This study proposes that all the known fundamental forces including gravity may be described by local gauge theories. Gravitational, electroweak, and strong interactions on length scales from 10^{-33} cm to 10^{28} cm are systematically discussed from the unified gauge theory point of view toward a ultimate theory for fundamental forces. New concepts such as dynamical spontaneous symmetry breaking, gauge group hierarchy, coupling constant hierarchy, effective coupling constant hierarchy, cosm...
Testing local Lorentz invariance with gravitational waves
Kostelecky, Alan
2016-01-01
The effects of local Lorentz violation on dispersion and birefringence of gravitational waves are investigated. The covariant dispersion relation for gravitational waves involving gauge-invariant Lorentz-violating operators of arbitrary mass dimension is constructed. The chirp signal from the gravitational-wave event GW150914 is used to place numerous first constraints on gravitational Lorentz violation.
Black hole spectra in holography: Consequences for equilibration of dual gauge theories
Directory of Open Access Journals (Sweden)
Alex Buchel
2015-07-01
Full Text Available For a closed system to equilibrate from a given initial condition there must exist an equilibrium state with the energy equal to the initial one. Equilibrium states of a strongly coupled gauge theory with a gravitational holographic dual are represented by black holes. We study the spectrum of black holes in Pilch–Warner geometry. These black holes are holographically dual to equilibrium states of strongly coupled SU(N N=2? gauge theory plasma on S3 in the planar limit. We find that there is no energy gap in the black hole spectrum. Thus, there is a priori no obstruction for equilibration of arbitrary low-energy states in the theory via a small black hole gravitational collapse. The latter is contrasted with phenomenological examples of holography with dual four-dimensional CFTs having non-equal central charges in the stress–energy tensor trace anomaly.
Energy Technology Data Exchange (ETDEWEB)
Bachas, C. [Laboratoire de Physique Theorique, ENS, 75 - Paris (France); Bilal, A. [Institut de Physique, Universite de Neuchatel, (Switzerland); Douglas, M. [New Jersey University, Dept. of Physics and Astronomy, Piscataway, NJ (United States); Nekrasov, N. [IHES, Institut des Hautes Etudes Scientifiques, 91 - Bures sur Yvette (France); David, F. [CEA Saclay, Service de Physique Theorique, 91 - Gif-sur-Yvette (France)
2002-07-01
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.)
Gauge Invariant Spectral Cauchy Characteristic Extraction
Handmer, Casey J; Winicour, Jeffrey
2015-01-01
We present gauge invariant spectral Cauchy characteristic extraction. We compare gravitational waveforms extracted from a head-on black hole merger simulated in two different gauges by two different codes. We show rapid convergence, demonstrating both gauge invariance of the extraction algorithm and consistency between the legacy Pitt null code and the much faster Spectral Einstein Code (SpEC).
Gauge invariant spectral Cauchy characteristic extraction
Handmer, Casey J.; Szilágyi, Béla; Winicour, Jeffrey
2015-12-01
We present gauge invariant spectral Cauchy characteristic extraction. We compare gravitational waveforms extracted from a head-on black hole merger simulated in two different gauges by two different codes. We show rapid convergence, demonstrating both gauge invariance of the extraction algorithm and consistency between the legacy Pitt null code and the much faster spectral Einstein code (SpEC).
Holography with Gravitational Chern-Simons Term
Solodukhin, Sergey N.
2005-01-01
The holographic description in the presence of gravitational Chern-Simons term is studied. The modified gravitational equations are integrated by using the Fefferman-Graham expansion and the holographic stress-energy tensor is identified. The stress-energy tensor has both conformal anomaly and gravitational or, if re-formulated in terms of the zweibein, Lorentz anomaly. We comment on the structure of anomalies in two dimensions and show that the two-dimensional stress-energy...
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Techniques employed in nuclear gauges for the measurement of level, thickness, density and moisture are described. The gauges include both transmission and backscatter gauges and utilize alpha particles, beta particles, neutrons or gamma radiation
Hossenfelder, S
2006-01-01
We examine the possibility of a symmetry between gravitating and anti-gravitating particles. The properties of the anti-gravitating quantum fields are defined by the behavior under Lorentz- and gauge- transformations. The equations of motion and the conserved canonical currents are derived and it is shown that the kinetic energy remains positive whereas the source term to the field equations of General Relativity changes its sign. Furthermore, the interaction between gravitational and anti-gravitational fields is mediated by the graviton only, such that the coupling is naturally suppressed by the Planck scale. We discuss that in a scenario with extra dimensions, the production of anti-gravitating matter becomes possible at the LHC. We also briefly comment on cosmological implications.
Path Integrals and Anomalies in Curved Space
International Nuclear Information System (INIS)
Bastianelli and van Nieuwenhuizen's monograph 'Path Integrals and Anomalies in Curved Space' collects in one volume the results of the authors' 15-year research programme on anomalies that arise in Feynman diagrams of quantum field theories on curved manifolds. The programme was spurred by the path-integral techniques introduced in Alvarez-Gaume and Witten's renowned 1983 paper on gravitational anomalies which, together with the anomaly cancellation paper by Green and Schwarz, led to the string theory explosion of the 1980s. The authors have produced a tour de force, giving a comprehensive and pedagogical exposition of material that is central to current research. The first part of the book develops from scratch a formalism for defining and evaluating quantum mechanical path integrals in nonlinear sigma models, using time slicing regularization, mode regularization and dimensional regularization. The second part applies this formalism to quantum fields of spin 0, 1/2, 1 and 3/2 and to self-dual antisymmetric tensor fields. The book concludes with a discussion of gravitational anomalies in 10-dimensional supergravities, for both classical and exceptional gauge groups. The target audience is researchers and graduate students in curved spacetime quantum field theory and string theory, and the aims, style and pedagogical level have been chosen with this audience in mind. Path integrals are treated as calculational tools, and the notation and terminology are throughout tailored to calculational convenience, rather than to mathematical rigour. The style is closer to that of an exceedingly thorough and self-contained review article than to that of a textbook. As the authors mention, the first part of the book can be used as an introduction to path integrals in quantum mechanics, although in a classroom setting perhaps more likely as supplementary reading than a primary class text. Readers outside the core audience, including this reviewer, will gain from the book a heightened appreciation of the central role of regularization as a defining ingredient of a quantum field theory and will be impressed by the agreement of results arising from different regularization schemes. The readers may in particular enjoy the authors' 'brief history of anomalies' in quantum field theory, as well as a similar historical discussion of path integrals in quantum mechanics. (book review)
Determination of Cosmological Constant from Gauge Theory of Gravity
Wu, Ning; Resconi, Germano; Xu, Zhan; Zheng, Zhi-Peng; Zhang, Da-Hua; Ruan, Tu-Nan
2001-01-01
Combining general relativity and gravitational gauge theory, the cosmological constant is determined theoretically. The cosmological constant is related to the average vacuum energy of gravitational gauge field. Because the vacuum energy of gravitational gauge field is negative, the cosmological constant is positive, which generates repulsive force on stars to make the expansion rate of the Universe accelerated. A rough estimation of it gives out its magnitude of the order o...
Gravitational Energy-Momentum Density in Teleparallel Gravity
de Andrade, V. C.(Instituto de Física, Universidade de Brasília, 70919-970, Brasília, DF, Brazil); Guillen, L. C. T.; Pereira, J. G.
2000-01-01
In the context of a gauge theory for the translation group, a conserved energy-momentum gauge current for the gravitational field is obtained. It is a true spacetime and gauge tensor, and transforms covariantly under global Lorentz transformations. By rewriting the gauge gravitational field equation in a purely spacetime form, it becomes the teleparallel equivalent of Einstein's equation, and the gauge current reduces to the M{\\o}ller's canonical energy-momentum density of t...
Gravitational Analog of the Electromagnetic Poynting Vector
de Menezes, L. M.
1998-01-01
The gravitational analog of the electromagnetic Poynting vector is constructed using the field equations of general relativity in the Hilbert gauge. It is found that when the gravitational Poynting vector is applied to the solution of the linear mass quadrupole oscillator, the correct gravitational quadrupole radiation flux is obtained. Further to this, the Maxwell-like gravitational Poynting vector gives rise to Einstein's quadrupole radiation formula. The gravitational ene...
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We discuss gravitational backgrounds where supersymmetry is broken at the end of a warped throat, and the SUSY-breaking is transmitted to the Standard Model via gauginos which live in (part of) the bulk of the throat geometry. We find that the leading effect arises from splittings of certain 'messenger mesons,' which are adjoint KK-modes of the D-branes supporting the Standard Model gauge group. This picture is a gravity dual of a strongly coupled field theory where SUSY is broken in a hidden sector and transmitted to the Standard Model via a relative of semi-direct gauge mediation.
Energy Technology Data Exchange (ETDEWEB)
Benini, Francesco; /Princeton U.; Dymarsky, Anatoly; /Stanford U., ITP; Franco, Sebastian; /Santa Barbara, KITP; Kachru, Shamit; Simic, Dusan; /Stanford U., ITP /SLAC; Verlinde, Herman; /Princeton, Inst. Advanced Study
2009-06-19
We discuss gravitational backgrounds where supersymmetry is broken at the end of a warped throat, and the SUSY-breaking is transmitted to the Standard Model via gauginos which live in (part of) the bulk of the throat geometry. We find that the leading effect arises from splittings of certain 'messenger mesons,' which are adjoint KK-modes of the D-branes supporting the Standard Model gauge group. This picture is a gravity dual of a strongly coupled field theory where SUSY is broken in a hidden sector and transmitted to the Standard Model via a relative of semi-direct gauge mediation.
Benini, Francesco; Franco, Sebastian; Kachru, Shamit; Simic, Dusan; Verlinde, Herman
2009-01-01
We discuss gravitational backgrounds where supersymmetry is broken at the end of a warped throat, and the SUSY-breaking is transmitted to the Standard Model via gauginos which live in (part of) the bulk of the throat geometry. We find that the leading effect arises from splittings of certain "messenger mesons," which are adjoint KK-modes of the D-branes supporting the Standard Model gauge group. This picture is a gravity dual of a strongly coupled field theory where SUSY is broken in a hidden sector and transmitted to the Standard Model via a relative of semi-direct gauge mediation.
International Nuclear Information System (INIS)
We discuss gravitational backgrounds where supersymmetry is broken at the end of a warped throat, and the SUSY-breaking is transmitted to the Standard Model via gauginos which live in (part of) the bulk of the throat geometry. We find that the leading effect arises from splittings of certain 'messenger mesons', which are adjoint KK-modes of the D-branes supporting the Standard Model gauge group. This picture is a gravity dual of a strongly coupled field theory where SUSY is broken in a hidden sector and transmitted to the Standard Model via a relative of semi-direct gauge mediation.
Benini, Francesco; Dymarsky, Anatoly; Franco, Sebastián; Kachru, Shamit; Simic, Dusan; Verlinde, Herman
2009-12-01
We discuss gravitational backgrounds where supersymmetry is broken at the end of a warped throat, and the SUSY-breaking is transmitted to the Standard Model via gauginos which live in (part of) the bulk of the throat geometry. We find that the leading effect arises from splittings of certain ``messenger mesons," which are adjoint KK-modes of the D-branes supporting the Standard Model gauge group. This picture is a gravity dual of a strongly coupled field theory where SUSY is broken in a hidden sector and transmitted to the Standard Model via a relative of semi-direct gauge mediation.
Gauge-invariance in one-loop quantum cosmology
Vasilevich, D V
1995-01-01
We study the problem of gauge-invariance and gauge-dependence in one-loop quantum cosmology. We formulate some requirements which should be satisfied by boundary conditions in order to give gauge-independent path integral. The case of QED is studied in some detail. We outline difficulties in gauge-invariant quantization of gravitational field in a bounded region.
How to test gravitation theories by means of gravitational-wave measurements
Thorne, K. S.
1974-01-01
Gravitational-wave experiments are a potentially powerful tool for testing gravitation theories. Most theories in the literature predict rather different polarization properties for gravitational waves than are predicted by general relativity; and many theories predict anomalies in the propagation speeds of gravitational waves.
Gravitational energy and gravitational waves
International Nuclear Information System (INIS)
The papers of the International symposium after N.I. Lobachevsky Gravitational energy and gravitational waves at Dubna in December 1993 are presented. The main attention is paid to the gravitation theory, gravitational field energy density, gravitational waves and radiation
The Effective Gravitational Theory at Large Scale with Lorentz Violation
Wu, Yiwei; Yang, Lixiang; Yuan, Tzu-Chiang
2015-01-01
The dipole anomaly in the power spectrum of CMB may indicate that the Lorentz boost invarianc is violated at cosmic scale. We assume that the Lorentz symmetry is violated partly from the scale of galaxy. We employ the symmetry of very special relativity as an example to illustrate the Lorentz violation effect by constructing the corresponding gauge theories as the effective gravitational theory at the large scale. We find the common feather of these gravitation models is the non-triviality of spacetime torsion and contorsion even if the matter source is of only scalar matter. The presence of non-trivial contorsion contributes an effective enenrgy-momentum distribution which may account for part of dark matter effect.
Gauge conditions and gauge transformations
International Nuclear Information System (INIS)
The principal problems of gauge fixation in field theories are discussed. It is stressed the importance of the Dirac extended gauge group and of the weak gauge invariance of the physical quantities. The importance of distinguishing of dynamical gauges from non-dynamical ones is pointed out. Mainly in electrodynamics the role of the physical degrees of freedom in some popular gauges is analysed. It is shown the key role of the Fock gauge. The principal difference between local and global gauge transformations and their physical sense is elucidated. 148 refs., 3 figs
Galilean Theories of Gravitation
Pietri, R; Lusanna, L.; Pauri, M.
1992-01-01
A generalization of Newtonian gravitation theory is obtained by a suitable limiting procedure from the ADM action of general relativity coupled to a mass-point. Three particular theories are discussed and it is found that two of them are invariant under an extended Galilei gauge group.
Entanglement Entropy & Anomaly Inflow
Hughes, Taylor L.; Leigh, Robert G.; Parrikar, Onkar; Ramamurthy, Srinidhi T.
2015-01-01
We study entanglement entropy for parity-violating (time-reversal breaking) quantum field theories on $\\mathbb{R}^{1,2}$ in the presence of a domain wall between two distinct parity-odd phases. The domain wall hosts a 1+1-dimensional conformal field theory (CFT) with non-trivial chiral central charge. Such a CFT possesses gravitational anomalies. It has been shown recently that, as a consequence, its intrinsic entanglement entropy is sensitive to Lorentz boosts around the en...
International Nuclear Information System (INIS)
The mathematics of gauge fields and some related concepts are discussed: some corrections on the principal fiber bundles emphasize the idea that the present formulation of continuum theories is incomplete. The main ingredients used through the construction of the renormalized perturbation series are then described: the Faddeev Popov argument, and the Faddeev Popov Lagrangian; the Slavnov symmetry and the nature of the Faddeev Popov ghost fields; the Slavnov identity, with an obstruction: the Adler Bardeen anomaly, and its generalization to the local cohomology of the gauge Lie algebra. Some smooth classical configurations of gauge fields which ought to play a prominent role in the evaluation of the functional integral describing the theory are also reviewed
Igarashi, Yuji; Sato, Masanao; Sonoda, Hidenori; 10.1143/PTP.125.565
2011-01-01
The antifield formalism adapted in the exact renormalization group is found to be useful for describing a system with some symmetry, especially the gauge symmetry. In the formalism, the vanishing of the quantum master operator implies the presence of a symmetry. The QM operator satisfies a simple algebraic relation that will be shown to be related to the Wess-Zumino condition for anomalies. We also explain how an anomaly contributes to the QM operator.
International Nuclear Information System (INIS)
The antifield formalism adapted in the exact renormalization group is found to be useful for describing a system with some symmetry, especially the gauge symmetry. In the formalism, the vanishing of the quantum master operator implies the presence of a symmetry. The QM operator satisfies a simple algebraic relation that will be shown to be related to the Wess-Zumino condition for anomalies. We also explain how an anomaly contributes to the QM operator. (author)
National Oceanic and Atmospheric Administration, Department of Commerce — Bogus - Spacecraft anomalies due to the space environment range from minor operational problems to permanent spacecraft failure. The NGDC Spacecraft Anomaly...
National Oceanic and Atmospheric Administration, Department of Commerce â€” Bogus - Spacecraft anomalies due to the space environment range from minor operational problems to permanent spacecraft failure. The NGDC Spacecraft Anomaly...
Renormalization of the axial anomaly operators
Energy Technology Data Exchange (ETDEWEB)
Espriu, D.; Tarrach, R.
1982-12-01
The renormalization of the three pseudoscalar gauge invariant operators which appear in the Adler-Bell-Jackiw anomaly is studied in the background field gauge, where it is simplest. We analyse questions concerning renormalization-group invariance, mixing, the ..gamma../sup 5/-prescription in D dimensions, as well as the meaning of the nonrenormalization of the axial anomaly in the context of the renormalization of composite operators.
Relevance of induced gauge interactions in decoherence
International Nuclear Information System (INIS)
Decoherence in quantum cosmology is shown to occur naturally in the presence of induced geometric gauge interactions associated with particle production. A new ''gauge'' - variant form of the semiclassical Einstein equations is also presented which makes the non-gravitating character of the vacuum polarization energy explicit. (author). 20 refs
Gravity, Gauge Theories and Geometric Algebra
Lasenby, Anthony; Doran, Chris; Gull, Stephen
2004-01-01
A new gauge theory of gravity is presented. The theory is constructed in a flat background spacetime and employs gauge fields to ensure that all relations between physical quantities are independent of the positions and orientations of the matter fields. In this manner all properties of the background spacetime are removed from physics, and what remains are a set of `intrinsic' relations between physical fields. The properties of the gravitational gauge fields are derived from both classical ...
Tensor gauge condition and tensor field decomposition
Chen, Xiang-Song; Zhu, Ben-Chao
2011-01-01
We discuss various proposals of separating a tensor field into pure-gauge and gauge-invariant components. Such tensor field decomposition is intimately related to the effort of identifying the real gravitational degrees of freedom out of the metric tensor in Einstein's general relativity. We show that, as for a vector field, the tensor field decomposition has exact correspondence to, and can be derived from, the gauge-fixing approach. The complication for the tensor field, h...
Konishi Anomalies and Curves without Adjoints
Landsteiner, K
2004-01-01
Generalized Konishi anomaly relations in the chiral ring of N=1 supersymmetric gauge theories with unitary gauge group and chiral matter field in two-index tensor representations are derived. Contrary to previous investigations of related models we do not include matter multiplets in the adjoint representation. The corresponding curves turn out to be hyperelliptic. We also point out equivalences to models with orthogonal or symplectic gauge groups.
Konishi anomalies and curves without adjoints
International Nuclear Information System (INIS)
Generalized Konishi anomaly relations in the chiral ring of N=1 supersymmetric gauge theories with unitary gauge group and chiral matter field in two-index tensor representations are derived. Contrary to previous investigations of related models we do not include matter multiplets in the adjoint representation. The corresponding curves turn out to be hyperelliptic. We also point out equivalences to models with orthogonal or symplectic gauge groups
Axial anomaly and Atiyah-Singer theorem
International Nuclear Information System (INIS)
The fermion integration for gauge theories requires the study of the Euclidean c number Dirac equation in arbitrary external gauge fields. Winding of Asub(?) leads to a trapping for the Euclidean psi's. The authors complete their previous discussion by relating this problem to the Atiyah-Singer index theory. For gauge theories a suitably modified axial anomaly relation provides a new proof of this theorem. (Auth.)
Global Anomalies and Effective Field Theory
Golkar, Siavash
2015-01-01
We show that matching anomalies under large gauge transformations and large diffeomorphisms can explain the appearance and non-renormalization of couplings in effective field theory. We focus on %thermal partition functions and thermal effective field theory where we argue that the appearance of certain unusual Chern-Simons couplings is a consequence of global anomalies. As an example, we show that a mixed global anomaly in four dimensions fixes the chiral vortical effect coefficient. This is an experimentally measurable prediction from a global anomaly. For certain situations, we propose a simpler method for calculating global anomalies which uses correlation functions rather than eta invariants.
Low-Scale Gauge Mediation with a 100 TeV Gravitino
Asano, Masaki; Yokozaki, Norimi
2015-01-01
We propose a new framework of low-scale gauge-mediated supersymmetry (SUSY) breaking with a gravitino mass of O(100) TeV. The usual 4D gauge mediation models predict a light gravitino and suffer from cosmological problems. In our framework, a heavy gravitino in gauge mediation is realized with a flat extra-dimension, whose compactification scale is around the grand unified theory scale. Superparticle masses of the visible sector from gravity/anomaly mediation are suppressed, and they are purely generated by usual gauge mediation on the visible brane. Importantly, the Higgs Bmu-term vanishes at the leading order, which enables us to obtain the suitable mu-Bmu relation for the electroweak symmetry breaking. We discuss such models considering two possibilities of the SUSY breaking source: 1) Scherk-Schwarz SUSY breaking which we call Scherk-Schwarz Gauge Mediation and 2) gravitational SUSY breaking localized on a hidden brane. In the case 2), the cosmological moduli problem may be relaxed as well.
Anomalies, counterterms and the ${\\cal N} =0$ Polchinski-Strassler solutions
Taylor-Robinson, M M
2001-01-01
The singularity structure of many IIB supergravity solutions asymptotic to $AdS_5 \\times S^5$ becomes clearer when one considers the full ten dimensional solution rather than the dimensionally reduced solution of gauged supergravity. It has been shown that all divergences in the gravitational action of the dimensionally reduced spacetime can be removed by the addition of local counterterms on the boundary. Here we attempt to formulate the counterterm action directly in ten dimensions for a particular class of solutions, the ${\\cal N} = 0$ Polchinski-Strassler solutions, which are dual to an ${\\cal N} =4$ SYM theory perturbed by mass terms for all scalars and spinors. This involves constructing the solution perturbatively near the boundary. There is a contribution to the Weyl anomaly from the mass terms (which break the classical conformal invariance of the action). The coefficient of this anomaly is reproduced by a free field calculation indicating a non-renormalisation theorem inherited from the ${\\cal N} =4...
Higher derivative regularization and chiral anomaly
International Nuclear Information System (INIS)
A higher derivative regularization which automatically leads to the consistent chiral anomaly is analyzed in detail. It explicitly breaks all the local gauge symmetry but preserves global chiral symmetry and leads to the chirally symmetric consistent anomaly. This regularization thus clarifies the physics content contained in the consistent anomaly. We also briefly comment on the application of this higher derivative regularization to massless QED. (author)
Underdevelopment's gravitation
Marin Dinu
2013-01-01
The energy necessary to escape the gravitational pull of underdevelopment and to enter an evolutional trajectory dependent on the gravitational pull of development is unintelligible in economic terms.
International Nuclear Information System (INIS)
It is known that a hierarchial spontaneous breakdown of a gauge symmetry can occur with enormous ratios of 'super-heavy' and 'ordinary' gauge boson masses. A sufficient condition is that the initial spontaneous breakdown of the over-all gauge group should leave some scalars with small or zero masses. If these scalars have zero masses, the ratios of superheavy and ordinary gauge boson masses will automatically be of the form exp(C/g2), where C is typically of order unity, and g is a representative gauge coupling. Numerical calculations show that these ratios can easily be as large as needed in a grand unification of QCD with SU(2) X U(1). For a range of parameters, there is an absolute upper bound on these ratios, which is larger by a factor exp (1/4) than the vlaues for zero scalar mass. (Auth.)
Symplectic gauge fields and dark matter
Asorey, J; Garcia-Alvarez, D
2015-01-01
The dynamics of symplectic gauge fields provides a consistent framework for fundamental interactions based on spin three gauge fields. One remarkable property is that symplectic gauge fields only have minimal couplings with gravitational fields and not with any other field of the Standard Model. Interactions with ordinary matter and radiation can only arise from radiative corrections. In spite of the gauge nature of symplectic fields they acquire a mass by the Coleman-Weinberg mechanism which generates Higgs-like mass terms where the gravitational field is playing the role of a Higgs field. Massive symplectic gauge fields weakly interacting with ordinary matter are natural candidates for the dark matter component of the Universe.
Symplectic gauge fields and dark matter
Asorey, J.; Asorey, M.; García-Álvarez, D.
2015-11-01
The dynamics of symplectic gauge fields provides a consistent framework for fundamental interactions based on spin-3 gauge fields. One remarkable property is that symplectic gauge fields only have minimal couplings with gravitational fields and not with any other field of the Standard Model. Interactions with ordinary matter and radiation can only arise from radiative corrections. In spite of the gauge nature of symplectic fields they acquire a mass by the Coleman-Weinberg mechanism which generates Higgs-like mass terms where the gravitational field is playing the role of a Higgs field. Massive symplectic gauge fields weakly interacting with ordinary matter are natural candidates for the dark matter component of the Universe.
Quaternion gauge theory of dyonic fields
International Nuclear Information System (INIS)
Outlining the idea of quaternion non-Abelian gauge formalism and that of the structural symmetry between generalized fields of dyons and gravito-dyons, it is shown that this formulation characterizes the Abelian and non-Abelian structure of dyons in terms of pure real and imaginary unit quaternions. Extending this formalism to the case of gravito-dyons it has been shown that pure imaginary unit quaternions advocate the curvature in the theory of gravito-dyons and hence the SL(2,c) gauge group of gravitation plays the same role as that of SU(2) gauge group does in non-Abelian gauge theory. Furthermore, we have unified the theories of electromagnetism and gravitation in terms of single parameter Î± by means of quaternion-gauge formalism and the corresponding field equations have also been derived in a unique and consistent way. (author)
Clark, T. E.; Love, S. T.; Nitta, M; ter Veldhuis, T.; Xiong, C.
2006-01-01
Coset methods are used to construct the action describing the dynamics associated with the spontaneous breaking of the local Poincare symmetries of D dimensional space-time due to the embedding of a p-brane with codimension N=D-p-1. The resulting action is an ISO(1,p+N) invariant form of the Einstein-Hilbert action, which, in addition to the gravitational vielbein, also includes N massive gauge fields correspondin...
International Nuclear Information System (INIS)
This article is a survey of the history and ideas of gauge theory. Described here are the gradual emergence of symmetry as a driving force in the shaping of physical theory; the elevation of Noether's theorem, relating symmetries to conservation laws, to a fundamental principle of nature; and the force of the idea (''the gauge principle'') that the symmetries of nature, like the interactions themselves, should be local in character. The fundamental role of gauge fields in mediating the interactions of physics springs from Noether's theorem and the gauge principle in a remarkably clean and elegant way, leaving, however, some tantalizing loose ends that might prove to be the clue to a future deeper level of understanding. The example of the electromagnetic field as the prototype gauge theory is discussed in some detail and serves as the basis for examining the similarities and differences that emerge in generalizing to non-Abelian gauge theories. The article concludes with a brief examination of the dream of total unification: all the forces of nature in a single unified gauge theory, with the differences among the forces due to the specific way in which the fundamental symmetries are broken in the local environment
Perturbations of gravitational instantons
International Nuclear Information System (INIS)
Ashtekar's spinorial formulation of general relativity is used to study perturbations of gravitational instantons corresponding to finite-action solutions of the Euclidean Einstein equations (with a nonzero cosmological constant) possessing an anti-self-dual Weyl curvature tensor. It is shown that, with an appropriate ''on-shell'' form of infinitesimal gauge transformations, the space of solutions to the linearized instanton equation can be described in terms of an elliptic complex; the cohomology of the complex defines gauge-inequivalent perturbations. Using this elliptic complex we prove that there are no nontrivial solutions to the linearized instanton equation on conformally anti-self-dual Einstein spaces with a positive cosmological constant. Thus, the space of gravitational instantons is discrete when the cosmological constant is positive; i.e., the dimension of the gravitational moduli space in this case is zero. We discuss the issue of linearization stability as well as the feasibility of using the Atiyah-Singer index theorem to compute the dimension of the gravitational moduli space when the cosmological constant is negative
Calculation of the commutator anomaly
International Nuclear Information System (INIS)
It is well-known that, for the non-Abelian gauge theory coupled to the chiral fermions, which is described by a Lagrangian, the anomaly of the non-Abelian current is given by the descent form of the Chern-Simon five form; D*Ja = (-1/24?2)tr[d(AdA + 1/2A3)], where A = A?dx? = -itaA?adx?. Recently, Faddeev argued that, for such an anomalous system, the gauge symmetry would be represented in a generalized sense of projective representation; V(g1)V(g2)?(A) = exp[i?2(g1, g2; A)] X V(g1g2)?(A), where ?(A) is the wave functional and the phase factor ?2 depends on both the group elements and the gauge field configuration A. Here, it is convenient to consider the infinitesimal version of the above argument. The generator of infinitesimal gauge transformation in the temporal gauge A0 = 0 is given by Ga(x) = ?iEia + gfabcAibEic - g?-bar?0ta?, and the infinitesimal form of the previous product rule can be written as the equal time commutation relation; [Ga(x), Gb(y)] = ifabcGc(x)?3(x-y) + ab(x,y,A), where is related to ?2. In this equation, the first term is what is expected as the normal commutation relation of the generator, while the second term is an anomaly, which is designated here as the commutator anomaly. Then the present study concentrates on operations to determine the anomaly term. (Nogami, A.)
The earth's gravitational field
Digital Repository Service at National Institute of Oceanography (India)
Ramprasad, T.
of up to 200 metres in the Pacific ocean, and throwing pendulum clocks out of synchronisation. The study of these anomalies forms the basis of gravitational geophysics. The fluctuations are measured with highly sensitive gravimeters, the effect... sensors on the gimbals or the stabilized platforms. The Vening-Meinesz pendulum is the earliest instrument that has measured gravity at sea to an accuracy of 2 mGal on board submarines which could handle the small and long period accelerations...
Anomalous gauge theories as constrained Hamiltonian systems
International Nuclear Information System (INIS)
Anomalous gauge theories considered as constrained systems are investigated. The effects of chiral anomaly on the canonical structure are examined first for nonlinear Ïƒ-model and later for fermionic theory. The breakdown of the Gauss law constraints and the anomalous commutators among them are studied in a systematic way. An intrinsic mass term for gauge fields makes it possible to solve the Gauss law relations as second class constraints. Dirac brackets between the time components of gauge fields are shown to involve anomalous terms. Based upon the Ward-Takahashi identities for gauge symmetry, we investigate anomalous fermionic theory within the framework of path integral approach. (orig.)
Gauge Invariant Effective Action in Abelian Chiral Gauge Theory on the Lattice
Suzuki, Hiroshi(Department of Physics, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka, 812-8581, Japan)
1999-01-01
L\\"uscher's recent formulation of Abelian chiral gauge theories on the lattice, in the vacuum (or perturbative) sector in infinite volume, is reinterpreted in terms of the lattice covariant regularization. The gauge invariance of the effective action and the integrability of the gauge current in anomaly-free cases become transparent. The real part of the effective action is simply one-half that of the Dirac fermion and, when the Dirac operator behaves properly in the continu...
Entropy for gravitational Chern-Simons terms by squashed cone method
Guo, Wu-zhong
2015-01-01
In this paper we investigate the entropy of gravitational Chern-Simons terms for the horizon with non-vanishing extrinsic curvatures, or the holographic entanglement entropy for arbitrary entangling surface. In 3D we find no anomaly of entropy appears. But the squashed cone method can not be used directly to get the correct result. For higher dimensions the anomaly of entropy would appear, still, we can not use the squashed cone method directly. That is becasuse the Chern-Simons action is not gauge invariant. To get a reasonable result we suggest two methods. One is by adding a boundary term to recover the gauge invariance. This boundary term can be derived from the variation of the Chern-Simons action. The other one is by using the Chern-Simons relation $d\\bm{\\Omega_{4n-1}}=tr(\\bm{R}^{2n})$. We notice that the entropy of $tr(\\bm{R}^{2n})$ is a total derivative locally, i.e. $S=d s_{CS}$. We propose to identify $s_{CS}$ with the entropy of gravitational Chern-Simons terms $\\Omega_{4n-1}$. In the first method ...
The Nonlinear Essence of Gravitational Waves
Aldrovandi, R.; Pereira, J. G.; Vu, K. H.
2007-01-01
A critical review of gravitational wave theory is made. It is pointed out that the usual linear approach to the gravitational wave theory is neither conceptually consistent nor mathematically justified. Relying upon that analysis it is then argued that -- analogously to a Yang-Mills propagating field, which must be nonlinear to carry its gauge charge -- a gravitational wave must necessarily be nonlinear to transport its own charge -- that is, energy-momentum.
Energy Technology Data Exchange (ETDEWEB)
Batra, Puneet; /Argonne; Dobrescu, Bogdan A.; /Fermilab; Spivak, David; /UC, Berkeley, Math. Dept.
2005-10-01
We present new techniques for finding anomaly-free sets of fermions. Although the anomaly cancellation conditions typically include cubic equations with integer variables that cannot be solved in general, we prove by construction that any chiral set of fermions can be embedded in a larger set of fermions which is chiral and anomaly-free. Applying these techniques to extensions of the Standard Model, we find anomaly-free models that have arbitrary quark and lepton charges under an additional U(1) gauge group.
Vanishing Vierbein in Gauge Theories of Gravitation
Jadczyk, Arkadiusz
1999-01-01
Comment: Latex format. 15 pages, 2 figures in gif format, available also for downloads at http://www.cassiopaea.org/images/traj.gif and http://www.cassiopaea.org/images/bubble.gif respectively. This paper has been published as a preprint 1n 1982. After so many years I decided to make it available for a wider public, to include 1984 referee report with my comments, and also to add reference to a more recent work on degenerate metric, where this paper is quoted
Astrometric solar system anomalies
Energy Technology Data Exchange (ETDEWEB)
Nieto, Michael Martin [Los Alamos National Laboratory; Anderson, John D [PROPULSION LABORATORY
2009-01-01
There are at least four unexplained anomalies connected with astrometric data. perhaps the most disturbing is the fact that when a spacecraft on a flyby trajectory approaches the Earth within 2000 km or less, it often experiences a change in total orbital energy per unit mass. next, a secular change in the astronomical unit AU is definitely a concern. It is increasing by about 15 cm yr{sup -1}. The other two anomalies are perhaps less disturbing because of known sources of nongravitational acceleration. The first is an apparent slowing of the two Pioneer spacecraft as they exit the solar system in opposite directions. Some astronomers and physicists are convinced this effect is of concern, but many others are convinced it is produced by a nearly identical thermal emission from both spacecraft, in a direction away from the Sun, thereby producing acceleration toward the Sun. The fourth anomaly is a measured increase in the eccentricity of the Moon's orbit. Here again, an increase is expected from tidal friction in both the Earth and Moon. However, there is a reported unexplained increase that is significant at the three-sigma level. It is produent to suspect that all four anomalies have mundane explanations, or that one or more anomalies are a result of systematic error. Yet they might eventually be explained by new physics. For example, a slightly modified theory of gravitation is not ruled out, perhaps analogous to Einstein's 1916 explanation for the excess precession of Mercury's perihelion.
Gauge invariant composite operators of QED in the exact renormalization group formalism
Sonoda, Hidenori
2013-01-01
Using the exact renormalization group (ERG) formalism, we study the gauge invariant composite operators in QED. Gauge invariant composite operators are introduced as infinitesimal changes of the gauge invariant Wilson action. We examine the dependence on the gauge fixing parameter of both the Wilson action and gauge invariant composite operators. After defining ``gauge fixing parameter independence,'' we show that any gauge independent composite operators can be made ``gauge fixing parameter independent'' by appropriate normalization. As an application, we give a concise but careful proof of the Adler-Bardeen non-renormalization theorem for the axial anomaly in an arbitrary covariant gauge by extending the original proof by A. Zee.
Anomalies, Beta Functions, and GUT's
International Nuclear Information System (INIS)
In the framework of supersymmetric Grand Unified theories it is possible to extend the minimal Higgs sectors of the models by introducing high dimension (anomaly free) representations. For example, in the minimal SU(5) supersymmetric Grand Unified Model, this is done to obtain phenomenological viable fermion mass relations and/or to solve the doublet-triplet splitting problem. In this work we explore models with different anomaly free combinations of SU(5) representations motivated by the flavour problem as well as their effect on perturbative validity of the gauge coupling evolution.
Tensor gauge condition and tensor field decomposition
Zhu, Ben-Chao; Chen, Xiang-Song
2015-10-01
We discuss various proposals of separating a tensor field into pure-gauge and gauge-invariant components. Such tensor field decomposition is intimately related to the effort of identifying the real gravitational degrees of freedom out of the metric tensor in Einstein’s general relativity. We show that as for a vector field, the tensor field decomposition has exact correspondence to and can be derived from the gauge-fixing approach. The complication for the tensor field, however, is that there are infinitely many complete gauge conditions in contrast to the uniqueness of Coulomb gauge for a vector field. The cause of such complication, as we reveal, is the emergence of a peculiar gauge-invariant pure-gauge construction for any gauge field of spin ? 2. We make an extensive exploration of the complete tensor gauge conditions and their corresponding tensor field decompositions, regarding mathematical structures, equations of motion for the fields and nonlinear properties. Apparently, no single choice is superior in all aspects, due to an awkward fact that no gauge-fixing can reduce a tensor field to be purely dynamical (i.e. transverse and traceless), as can the Coulomb gauge in a vector case.
International Nuclear Information System (INIS)
History of discovery and study of gravitational lenses is discussed. Vitational focusing is based on refraction of light beams in an inhomogeneous gravitational field of a star. The effect of gravitational . focusing. The gravitational field acts like a collecting lens. The role of the gravitational lens can be played not only by individual stars but whole galaxies as well. In March 1979 optical spectra of quasar 0957 + 561 A,B have been obtained. Spectra of quasar components turned out to be identical. This circumstance confirmed a hypothesis of the gravitational lens reality
Turyshev, Slava G
2010-01-01
Radio-metric Doppler tracking data received from the Pioneer 10 and 11 spacecraft from heliocentric distances of 20-70 AU has consistently indicated the presence of a small, anomalous, blue-shifted frequency drift uniformly changing with a rate of ~6 x 10^{-9} Hz/s. Ultimately, the drift was interpreted as a constant sunward deceleration of each particular spacecraft at the level of a_P = (8.74 +/- 1.33) x 10^{-10} m/s^2. This apparent violation of the Newton's gravitational inverse-square law has become known as the Pioneer anomaly; the nature of this anomaly remains unexplained. In this review, we summarize the current knowledge of the physical properties of the discovered effect and the conditions that led to its detection and characterization. We review various mechanisms proposed to explain the anomaly and discuss the current state of efforts to determine its nature. A comprehensive new investigation of the anomalous behavior of the two Pioneers has begun recently. The new efforts rely on the much-extend...
International Nuclear Information System (INIS)
In these notes the author provides some background on the theory of gauge fields, a subject of increasing popularity among particle physicists (and others). Detailed motivations and applications which are covered in the other lectures of this school are not presented. In particular the application to weak interactions is omitted by referring to the introduction given by J. Ilipoulos a year ago (CERN Report 76-11). The aim is rather to stress those aspects which suggest that gauge fields may play some role in a future theory of strong interactions. (Auth.)
Anomaly Mediation in Local Effective Theories
Dine, Michael
2013-01-01
The phenomenon known as "anomaly mediation" can be understood in a variety of ways. Rather than an anomaly, certain gaugino bilinear terms are required by local supersymmetry and gauge invariance (the derivation of these terms is in some cases related to anomalies in scale invariance or $R$ symmetries). We explain why the gaugino bilinear is required in supersymmetric gauge theories with varying number of colors and flavors. By working in the Higgs phase, gauging a flavor group, or working below the scale of gaugino condensation, each of these theories has a local effective description in which we can identify the bilinear term, establishing its necessity in the microscopic theory. For example, in theories that exhibit gaugino condensation, the potential in the very low energy theory is supersymmetric precisely due to the relation between the nonperturbative superpotential and the gaugino bilinear terms. Similarly, the gravitino mass appears from its coupling to the gaugino bilinear.
Gauge and Gravity Amplitude Relations
Carrasco, John Joseph M
2015-01-01
In these lectures I talk about simplifications and universalities found in scattering amplitudes for gauge and gravity theories. In contrast to Ward identities, which are understood to arise from familiar symmetries of the classical action, these structures are currently only understood in terms of graphical organizational principles, such as the gauge-theoretic color-kinematics duality and the gravitational double-copy structure, for local representations of multi-loop S-matrix elements. These graphical principles make manifest new relationships in and between gauge and gravity scattering amplitudes. My lectures will focus on arriving at such graphical organizations for generic theories with examples presented from maximal supersymmetry, and their use in unitarity-based multi-loop integrand construction.
Differential formalism aspects of the gauge classical theories
International Nuclear Information System (INIS)
The classical aspects of the gauge theories are shown using differential geometry as fundamental tool. Somme comments are done about Maxwell Electro-dynamics, classical Yang-Mills and gravitation theories. (L.C.)
Differential renormalization of gauge theories
International Nuclear Information System (INIS)
The scope of constrained differential renormalization is to provide renormalized expressions for Feynman graphs, preserving at the same time the Ward identities of the theory. It has been shown recently that this can be done consistently at least to one loop for Abelian and non-Abelian gauge theories. We briefly review these results, evaluate as an example the gluon self energy in both coordinate and momentum space, and comment on anomalies. (author)
Differential renormalization of gauge theories
Energy Technology Data Exchange (ETDEWEB)
Aguila, F. del; Perez-Victoria, M. [Dept. de Fisica Teorica y del Cosmos, Universidad de Granada, Granada (Spain)
1998-10-01
The scope of constrained differential renormalization is to provide renormalized expressions for Feynman graphs, preserving at the same time the Ward identities of the theory. It has been shown recently that this can be done consistently at least to one loop for Abelian and non-Abelian gauge theories. We briefly review these results, evaluate as an example the gluon self energy in both coordinate and momentum space, and comment on anomalies. (author) 9 refs, 1 fig., 1 tab
Liouville action in cone gauge
International Nuclear Information System (INIS)
The effective action of the conformally invariant field theory in the curved background space is considered in the light cone gauge. The effective potential in the classical background stress is defined as the Legendre transform of the Liouville action. This potential is tightly connected with the sl(2) current algebra. The series of the covariant differential operators is constructed and the anomalies of their determinants are reduced to this effective potential. 7 refs
The gauge theory of the translation group and underlying geometry
International Nuclear Information System (INIS)
The author finds that the gauge theory of the translation group is a gravitational theory based on the Weitzenboeck space, called New General Relativity in contrast to General Relativity on the Riemann space. Both GR and NGR pass all the tests so far done. NGR ascribes gravitation to torsion alone but GR to curvature only. As a by-product a recent claim is disproved, that the present gauge-theory leads to GR. (Auth.)
Schutz, B F
2000-01-01
Gravity is one of the fundamental forces of Nature, and it is the dominant force in most astronomical systems. In common with all other phenomena, gravity must obey the principles of special relativity. In particular, gravitational forces must not be transmitted or communicated faster than light. This means that when the gravitational field of an object changes, the changes ripple outwards through space and take a finite time to reach other objects. These ripples are called gravitational radiation or gravitational waves. This article gives a brief introduction to the physics of gravitational radiation, including technical material suitable for non-specialist scientists.
Gravitational Waves from Gravitational Collapse
New Kimberly C.B.
2002-01-01
Gravitational wave emission from the gravitational collapse of massive stars has been studied for more than three decades. Current state of the art numerical investigations of collapse include those that use progenitors with realistic angular momentum profiles, properly treat microphysics issues, account for general relativity, and examine non--axisymmetric effects in three dimensions. Such simulations predict that gravitational waves from various phenomena associated with gravitational colla...
Gauge bosons production and properties
Rebassoo, Finn O'neill
2015-01-01
Studies of the production and decay of gauge bosons are an important probe of the electroweak sector of the standard model. Anomalies in these processes could be a sign of new physics, and are an indirect search for physics beyond the scale that can be directly measured at accelerators. The sensitivity to new physics depends on both the experimental uncertainty and standard model theoretical uncertainty, so reducing both of these is important for any discovery of new physics. This article will focus on the experimental measurements of these processes and specifically on results from the last year at the Tevatron and LHC, though relevant earlier measurements will be referenced. In addition to being sensitive to new physics, gauge boson production is a background to a lot of new physics models and Higgs measurements. Thus, measuring these processes precisely is of the utmost importance. Gauge boson production is also an important way to constrain parton distribution functions (pdfs), and test perturbative and n...
Gravitational lensing by gravitational waves
Bisnovatyi-Kogan, G S; Tsupko, O. Yu.
2008-01-01
Gravitational lensing by gravitational wave is considered. We notice that although final and initial direction of photons coincide, displacement between final and initial trajectories occurs. This displacement is calculated analytically for the plane gravitational wave pulse. Estimations for observations are discussed.
Axionic Defect Anomalies and their Cancellation
Izquierdo, J.M.; Townsend, P K
1993-01-01
We present a simple derivation of the Callan-Harvey-Naculich effect, {\\it i.e.} the compensation of charge violation on axion strings due to gauge anomalies by accretion of charge onto the string from the surrounding space. We then show, in the case of axion fields without a potential, that an alternative explanation is possible in which no reference to the surrounding space is necessary because the anomalies are cancelled by a version of the Green-Schwarz mechanism. We prov...
Gravitational wave detector response in terms of spacetime Riemann curvature
Koop, Michael J.; Finn, Lee Samuel
2013-01-01
Gravitational wave detectors are typically described as responding to gravitational wave metric perturbations, which are gauge-dependent and --- correspondingly --- unphysical quantities. This is particularly true for ground-based interferometric detectors, like LIGO, space-based detectors, like LISA and its derivatives, spacecraft doppler tracking detectors, and pulsar timing arrays detectors. The description of gravitational waves, and a gravitational wave detector's response, to the unphys...
International Nuclear Information System (INIS)
Enormous technical and economic benefits have been conferred on the industry in many countries by the application of nucleonic gauging. The last few years have witnessed many important advances in the field. Basically radioisotope instruments are used to measure a variety of physical properties of material in solid, liquid and gaseous state and many of them are designed to work in the industrial plants and fields under rigorous conditions
Torsional Anomalies, Hall Viscosity, and Bulk-boundary Correspondence in Topological States
Hughes, Taylor L; Parrikar, Onkar
2013-01-01
We study the transport properties of topological insulators, encoding them in a generating functional of gauge and gravitational sources. Much of our focus is on the simple example of a free massive Dirac fermion, the so-called Chern insulator, especially in 2+1 dimensions. In such cases, when parity and time-reversal symmetry are broken, it is necessary to consider the gravitational sources to include a frame and an independent spin connection with torsion. In 2+1 dimensions, the simplest parity-odd response is the Hall viscosity. We compute the Hall viscosity of the Chern insulator using a careful regularization scheme, and find that although the Hall viscosity is generally divergent, the difference in Hall viscosities of distinct topological phases is well-defined and determined by the mass gap. Furthermore, on a 1+1-dimensional edge between topological phases, the jump in the Hall viscosity across the interface is encoded, through familiar anomaly inflow mechanisms, in the structure of anomalies. In parti...
Konishi Anomalies and N=1 Curves
Landsteiner, K
2004-01-01
We present a brief summary of exact results on the non-perturbative effective superpotential of N=1 supersymmetric gauge theories based on generalized Konishi anomaly equations. In particular we consider theories with classical gauge groups and chiral matter in two-index tensor representations. All these theories can be embedded into theories with unitary gauge group and adjoint matter. This embedding can be used to derive expressions for the exact non-perturbative superpotential in terms of the 1/N expansion of the free energy of the related matrix models.
The Faddeev-Mickelsson-Shatashvili anomaly and lifting bundle gerbes
Hekmati, Pedram; Murray, Michael K; Stevenson, Danny; Vozzo, Raymond F.
2011-01-01
In gauge theory, the Faddeev-Mickelsson-Shatashvili anomaly arises as a prolongation problem for the action of the gauge group on a bundle of projective Fock spaces. In this paper, we study this anomaly from the point of view of bundle gerbes and give several equivalent descriptions of the obstruction. These include lifting bundle gerbes with non-trivial structure group bundle and bundle gerbes related to the caloron correspondence.
Two potentials, one gauge group: a possible geometrical motivation
International Nuclear Information System (INIS)
By studying the purely gravitational sector of a higher-dimensional matter-gravity coupled theory, one can see that in the case of nonvanishing torsion the effective 4-dimensional theory exhibits two gauge potentials that transform under the action of a single gauge group
Two potentials, one gauge group: A possible geometrical motivation
International Nuclear Information System (INIS)
By studying the purely gravitational sector of a higher dimensional matter-gravity coupled theory, one can see that in the case of non-vanishing torsion the effective 4-dimensional theory exhibits two gauge potentials that transform under the action of a single gauge group. (Author)
Loop equations, matrix models, and N=1 supersymmetric gauge theories
Kraus, Per(Department of Physics and Astronomy, University of California, 475 Portola Plaza, Los Angeles, CA, 90095, U.S.A.); Ryzhov, Anton V.; Shigemori, Masaki(Yukawa Institute for Theoretical Physics, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto, 606-8502, Japan)
2003-01-01
We derive the Konishi anomaly equations for N=1 supersymmetric gauge theories based on the classical gauge groups with matter in two-index tensor and fundamental representations, thus extending the existing results for U(N). A general formula is obtained which expresses solutions to the Konishi anomaly equation in terms of solutions to the loop equations of the corresponding matrix model. This provides an alternative to the diagrammatic proof that the perturbative part of the glueball superpo...
Three lectures on Poincare gauge theory
M. Blagojevic
2003-01-01
In these lectures we review the basic structure of Poincare gauge theory of gravity, with emphasis on its fundamental principles and geometric interpretation. A specific limit of this theory, defined by the teleparallel geometry of spacetime, is discussed as a viable alternative for the description of macroscopic gravitational phenomena.
International Nuclear Information System (INIS)
Gravitational waves propagate through space in the same way as electromagnetic waves, but the utmost weakness of the coupling between the matter and gravitational radiation field makes them very difficult to observe. There is no realistic event for an accretion on a neutron star or a black hole producing a gravitational radiation able to be detected. Only one possibility is left, the gravitational collapse itself. A gain of six orders of magnitude on the sensitivity of the detectors now available should allow such observation
Emergent gravity and chiral anomaly in Dirac semimetals in the presence of dislocations
Zubkov, M A
2015-01-01
We consider the recently discovered Dirac semimetals with two Dirac points $\\pm{\\bf K}$. In the presence of elastic deformations each fermion propagates in a curved space, whose metric is defined by the expansion of the effective Hamiltonian near the Dirac point. Besides, there is the emergent electromagnetic field that is defined by the shift of the Dirac point. We consider the case, when the deformations are caused by the dislocations. The dislocation carries singular torsion and the quantized flux of emergent magnetic field. Both torsion singularity and emergent magnetic flux may be observed in the scattering of quasiparticles on the dislocation due to Stodolsky and Aharonov - Bohm effects. We discuss quantum anomalies in the quasiparticle currents in the presence of emergent gauge and gravitational fields and the external electromagnetic field. In particular, it is demonstrated, that in the presence of external electric field the quasiparticles/holes are pumped from vacuum along the dislocation. The appea...
International Nuclear Information System (INIS)
Several detailed models have been proposed in the last few years in an attempt to unify weak and electromagnetic interactions, using gauge theories. These are based on a renormalisable field theory. An attempt is made to outline the patterns that have emerged from these models. The interesting point is that the various requirements of weak, and electromagnetic interactions along with some restrictions needed for strong interactions seem to lead to a broad picture of strong interactions. The results are analysed and reviewed. (K.B.)
Gravitational Waves from Gravitational Collapse
Directory of Open Access Journals (Sweden)
New Kimberly C.B.
2003-01-01
Full Text Available Gravitational wave emission from the gravitational collapse of massive stars has been studied for more than three decades. Current state-of-the-art numerical investigations of collapse include those that use progenitors with more realistic angular momentum profiles, properly treat microphysics issues, account for general relativity, and examine non-axisymmetric effects in three dimensions. Such simulations predict that gravitational waves from various phenomena associated with gravitational collapse could be detectable with ground-based and space-based interferometric observatories.
Schutz, Bernard F.
1990-01-01
In 1989 four groups around the world proposed the construction of large-scale laser interferometric gravitational wave detectors. The author reviews the design of these detectors, the problems of analysing their data, and the theory of the sources of the gravitational waves that they are designed to detect.
Weiss, R.; Muehlner, D. J.; Benford, R. L.; Owens, D. K.; Pierre, N. A.; Rosenbluh, M.
1972-01-01
Balloon measurements were made of the far infrared background radiation. The radiometer used and its calibration are discussed. An electromagnetically coupled broadband gravitational antenna is also considered. The proposed antenna design and noise sources in the antenna are reviewed. A comparison is made between interferometric broadband and resonant bar antennas for the detection of gravitational wave pulses.
International Nuclear Information System (INIS)
Gravitational waves are propagating fluctuations of gravitational fields, that is, '' ripples '' in space-time, generated mainly by moving massive bodies. These distortions of space-time travel with the speed of light. Every body in the path of such a wave feels a tidal gravitational force that acts perpendicular to the wave's direction of propagation; these forces change the distance between points, and the size of the changes is proportional to the distance between these points thus gravitational waves can be detected by devices which measure the induced length changes. The frequencies and the amplitudes of the waves are related to the motion of the masses involved. Thus, the analysis of gravitational waveforms allows us to learn about their source and, if there are more than two detectors involved in observation, to estimate the distance and position of their source on the sky. (author)
Gauge Invariant Descriptions of Gauge Polarizations Revisited
Guo, Zhi-Qiang
2013-01-01
We examine the feasibility of gauge invariant descriptions of the gluon polarization following the proposal that a gauge field can be decomposed into its physical part and its pure gauge part. We show that gauge invariant angular momentum currents can be constructed from summations of gauge variant Noether currents. We present novel expressions of the pure gauge field, which are used to formulate gauge invariant descriptions of the gluon spin and the photon spin. We show that the gauge invariant extension of the Chern-Simons current can describe the spins of the Laguerre-Gauss laser modes. We also discuss the relation of gauge invariant operators and the parton distributions constructed from Dirac variables.
The Energy-Momentum Tensor for Gravitational Interactions
Wyss, Walter
1999-01-01
Within the Lagrange formalism we show that the gauge invariant total energy-momentum tensor for gravitational interactions is zero. If the equations of motion are satisfied the energy tensor is conserved.
A Pseudospectral Method for Gravitational Wave Collapse
Hilditch, David; Bruegmann, Bernd
2015-01-01
We present a new pseudospectral code, bamps, for numerical relativity written with the evolution of collapsing gravitational waves in mind. We employ the first order generalized harmonic gauge formulation. The relevant theory is reviewed and the numerical method is critically examined and specialized for the task at hand. In particular we investigate formulation parameters, gauge and constraint preserving boundary conditions well-suited to non-vanishing gauge source functions. Different types of axisymmetric twist-free moment of time symmetry gravitational wave initial data are discussed. A treatment of the axisymmetric apparent horizon condition is presented with careful attention to regularity on axis. Our apparent horizon finder is then evaluated in a number of test cases. Moving on to evolutions, we investigate modifications to the generalized harmonic gauge constraint damping scheme to improve conservation in the strong field regime. We demonstrate strong-scaling of our pseudospectral penalty code. We em...
The Anomaly Structure of Regularized Supergravity
Butter, Daniel
2014-01-01
On-shell Pauli-Villars regularization of the one-loop divergences of supergravity theories is used to study the anomaly structure of supergravity and the cancellation of field theory anomalies under a $U(1)$ gauge transformation and under the T-duality group of modular transformations in effective supergravity theories with three K\\"ahler moduli $T^i$ obtained from orbifold compactification of the weakly coupled heterotic string. This procedure requires constraints on the chiral matter representations of the gauge group that are consistent with known results from orbifold compactifications. Pauli-Villars regulator fields allow for the cancellation of all quadratic and logarithmic divergences, as well as most linear divergences. If all linear divergences were canceled, the theory would be anomaly free, with noninvariance of the action arising only from Pauli-Villars masses. However there are linear divergences associated with nonrenormalizable gravitino/gaugino interactions that cannot be canceled by PV fields...
Studies On Phases Of Gauge Theories
Duan, Z P
2001-01-01
In this dissertation, we describe our studies on phases of gauge theories in the infrared. In Part I, we study the phases of chiral gauge theories whose spontaneous symmetry breaking is due to the strong attractive interaction between fermions. We discuss two chiral SU(N) gauge theories involving fermions in the symmetric and antisymmetric two-index tensor representations respectively. In addition to global anomaly matching, we employ a recently proposed inequality constraint on the number of effective low energy degrees of freedom of a theory, based on the thermodynamic free energy. Several possible zero temperature phases are consistent with the constraints. A simple picture for the phase structure emerges if these theories choose the phase, consistent with global anomaly matching, that minimizes the massless degree of freedom count defined through the free energy. In Part II, we study QCD at high density. In this region, due to the well-known BCS mechanism, even a small attractive interaction around the Fe...
Introduction to gauge theories
International Nuclear Information System (INIS)
In these lectures we present the key ingredients of theories with local gauge invariance. We introduce gauge invariance as a starting point for the construction of a certain class of field theories, both for abelian and nonabelian gauge groups. General implications of gauge invariance are discussed, and we outline in detail how gauge fields can acquire masses in a spontaneous fashion. (orig./HSI)
Plane gravitational waves in string theory
International Nuclear Information System (INIS)
We analyze the coset model ( E2c xE2c)/E2c and construct a class of exact string vacua which describe plane gravitational waves and their duals, generalizing the plane wave background found by Nappi and Witten. In particular, the vector gauging describes a two-parameter family of singular geometries with two isometries, which is dual to plane gravitational waves. In addition, there is a mixed vector-axial gauging which describes a one-parameter family of plane waves with five isometries. These two backgrounds are related by a duality transformation which generalizes the known axial-vector duality for abelian subgroups. ((orig.))
International Nuclear Information System (INIS)
A survey was made by Japan Atomic Industrial Forum, Inc., in August, 1979, on the uses of isotope-equipped measuring instruments in private industrial enterprises by sending questionnaires to 1372 enterprises using sealed radiation sources. The results are described. i.e. usage of isotope-equipped measuring instruments, the economic effects, and problems for the future, and also the general situation in this field. Such instruments used are gas chromatography apparatus, thickness, level and moisture gauges, sulfur analyzer, etc. Except the gas chromatography, the rest are mostly incorporated in automatic control systems. As the economic effects, there are the rises in productivity, quality and yield and the savings in materials, energy and manpower. While they are used to great advantage, there are still problems occasionally in measuring accuracy and others. (J.P.N.)
Mansouri-Chang gravitation theory
Pavelle, R.
1978-01-01
The gauge theory of gravitation introduced by Mansouri and Chang (1976) is investigated; a symbolic manipulation computer system generates the Mansouri-Chang field equations in various coordinate systems. It is found that all vacuum Einstein spaces are vacuum Mansouri-Chang spaces in four dimensions, though for higher dimensions an Einstein vacuum space is not generally a Mansouri-Chang solution. The possibility that no solutions of the Mansouri-Chang equations are not Einstein vacuum spaces is discussed.
Chiral anomaly, fermionic determinant and two dimensional models
International Nuclear Information System (INIS)
The chiral anomaly in random pair dimension is analysed. This anomaly is perturbatively calculated by dimensional regularization method. A new method for non-perturbative Jacobian calculation of a general chiral transformation, 1.e., finite and non-Abelian, is developed. This method is used for non-perturbative chiral anomaly calculation, as an alternative to bosonization of two-dimensional theories for massless fermions and to study the phenomenum of fermion number fractionalization. The fermionic determinant from two-dimensional quantum chromodynamics is also studied, and calculated, exactly, as in decoupling gauge as with out reference to a particular gauge. (M.C.K.)
International Nuclear Information System (INIS)
The potential cosmological sources of gravitational radiation and the detectors used to measure it are discussed, surveying the current status of investigations. Detectors characterized include room-temperature and cryogenic bars, torsion pendula, laser interferometric detectors, and space-based detectors. The sources are supernovae (e.g., SN 1987A) and gravitational collapses, coalescing compact-object binaries, pulsars, Wagoner stars, the stochastic background, and LF sources (black-hole formation in galactic centers, Galactic binaries, and stars falling into nearby black holes). Also considered are outstanding theoretical modeling problems with implications for gravitational-wave observations. 46 refs
Christiansen, Snorre Harald
2010-01-01
We provide an analogue of lattice gauge theory defined for simplicial meshes. More precisely we define a gauge invariant discrete action for which we prove consistence. Both gauge and scalar fields are included in the discussion.
Cohen, Timothy; Knapen, Simon
2015-01-01
We propose a simple model of split supersymmetry from gauge mediation. This model features gauginos that are parametrically a loop factor lighter than scalars, accommodates a Higgs boson mass of 125 GeV, and incorporates a simple solution to the $\\mu-b_\\mu$ problem. The gaugino mass suppression can be understood as resulting from collective symmetry breaking. Imposing collider bounds on $\\mu$ and requiring viable electroweak symmetry breaking implies small $a$-terms and small $\\tan \\beta$ -- the stop mass ranges from $10^5$ to $10^8 \\mbox{ GeV}$. In contrast with models with anomaly + gravity mediation (which also predict a one-loop loop suppression for gaugino masses), our gauge mediated scenario predicts aligned squark masses and a gravitino LSP. Gluinos, electroweakinos and Higgsinos can be accessible at the LHC and/or future colliders for a wide region of the allowed parameter space.
Cohomology for covariant anomalies
International Nuclear Information System (INIS)
We study a new cohomology approach to the covariant anomalies in detail. A set of differential forms is constructed from descent-like 'sidestepping' equations. From this set, we can derive the covariant anomalies including the commutator anomaly as well as the current anomaly with correct normalizations. We also discuss the relation to the conventional set of differential forms for the consistent anomalies. (author)
Shnir, Ya. M.
2015-12-01
We construct solutions of the 3 + 1 dimensional Faddeev-Skyrme model coupled to Einstein gravity. The solutions are static and asymptotically flat. They are characterized by a topological Hopf number. We investigate the dependence of the ADM masses of gravitating Hopfions on the gravitational coupling. When gravity is coupled to flat space solutions, a branch of gravitating Hopfion solutions arises and merges at a maximal value of the coupling constant with a second branch of solutions. This upper branch has no flat space limit. Instead, in the limit of a vanishing coupling constant, it connects to either the Bartnik-McKinnon or a generalized Bartnik-McKinnon solution. We further find that in the strong-coupling limit, there is no difference between the gravitating solitons of the Skyrme model and the Faddeev-Skyrme model.
International Nuclear Information System (INIS)
As predicted by general relativity, gravitation curves light rays, an effect which produces actual gravitational mirages: the image of a distant source is distorted, amplified, and multiplied by the mass of a galaxy close to the path of the rays. Astronomers have already detected several such configurations in the form of 'double' or 'multiple' quasars. They are using these to gain access to a range of information on galaxies, quasars and even the geometry of the Universe. (author)
Bini, Donato; Chicone, Carmen; Mashhoon, Bahram
2008-01-01
We study the linear post-Newtonian approximation to general relativity known as gravitoelectromagnetism (GEM); in particular, we examine the similarities and differences between GEM and electrodynamics. Notwithstanding some significant differences between them, we find that a special nonstationary metric in GEM can be employed to show {\\it explicitly} that it is possible to introduce gravitational induction within GEM in close analogy with Faraday's law of induction and Lenz's law in electrodynamics. Some of the physical implications of gravitational induction are briefly discussed.
International Nuclear Information System (INIS)
We study the linear post-Newtonian approximation to general relativity known as gravitoelectromagnetism (GEM); in particular, we examine the similarities and differences between GEM and electrodynamics. Notwithstanding some significant differences between them, we find that a special nonstationary metric in GEM can be employed to show explicitly that it is possible to introduce gravitational induction within GEM in close analogy with Faraday's law of induction and Lenz's law in electrodynamics. Some of the physical implications of gravitational induction are briefly discussed
Katz, Joseph
2005-01-01
Observers at rest in a stationary spacetime flat at infinity can measure small amounts of rest-mass+internal energies+kinetic energies+pressure energy in a small volume of fluid attached to a local inertial frame. The sum of these small amounts is the total "matter energy" for those observers. The total mass-energy minus the matter energy is the binding gravitational energy. Misner, Thorne and Wheeler evaluated the gravitational energy of a spherically symmetric static spacetime. Here we show...
Non-minimal gauge mediation and moduli stabilization
International Nuclear Information System (INIS)
In this Letter we consider U(1)A-gauged Polonyi model with two spurions coupled to a twisted closed string modulus. This offers a consistent setup for metastable SUSY breakdown which allows for moduli stabilization and naturally leads to gauge or hybrid gauge/gravitational mediation mechanism. Due to the presence of the second spurion one can arrange for a solution of the ? and B? problems in a version of modified Giudice-Masiero mechanism, which works both in the limit of pure gauge mediation and in the mixed regime of hybrid mediation.
Graviton as a pair of collinear gauge bosons
Directory of Open Access Journals (Sweden)
Stephan Stieberger
2014-12-01
Full Text Available We show that the mixed gravitational/gauge superstring amplitudes describing decays of massless closed strings – gravitons or dilatons – into a number of gauge bosons, can be written at the tree (disk level as linear combinations of pure open string amplitudes in which the graviton (or dilaton is replaced by a pair of collinear gauge bosons. Each of the constituent gauge bosons carry exactly one half of the original closed string momentum, while their ±1 helicities add up to ±2 for the graviton or to 0 for the dilaton.
One loop divergences and anomalies from chiral superfields in supergravity
Butter, Daniel
2009-01-01
We apply the heat kernel method (using Avramidi's non-recursive technique) to the study of the effective action of chiral matter in a complex representation of an arbitrary gauge sector coupled to background U(1) supergravity. This generalizes previous methods, which restricted to 1) real representations of the gauge sector in traditional Poincar\\'e supergravity or 2) vanishing supergravity background. In this new scheme, we identify a classical ambiguity in these theories which mixes the supergravity U(1) with the gauge U(1). At the quantum level, this ambiguity is maintained since the effective action changes only by a local counterterm as one shifts a U(1) factor between the supergravity and gauge sectors. An immediate application of our formalism is the calculation of the one-loop gauge, Kahler, and reparametrization anomalies of chiral matter coupled to minimal supergravity from purely chiral loops. Our approach gives an anomaly whose covariant part is both manifestly supersymmetric and non-perturbative ...
Light-induced gauge fields for ultracold atoms.
Goldman, N; Juzeli?nas, G; Öhberg, P; Spielman, I B
2014-12-01
Gauge fields are central in our modern understanding of physics at all scales. At the highest energy scales known, the microscopic universe is governed by particles interacting with each other through the exchange of gauge bosons. At the largest length scales, our Universe is ruled by gravity, whose gauge structure suggests the existence of a particle-the graviton-that mediates the gravitational force. At the mesoscopic scale, solid-state systems are subjected to gauge fields of different nature: materials can be immersed in external electromagnetic fields, but they can also feature emerging gauge fields in their low-energy description. In this review, we focus on another kind of gauge field: those engineered in systems of ultracold neutral atoms. In these setups, atoms are suitably coupled to laser fields that generate effective gauge potentials in their description. Neutral atoms 'feeling' laser-induced gauge potentials can potentially mimic the behavior of an electron gas subjected to a magnetic field, but also, the interaction of elementary particles with non-Abelian gauge fields. Here, we review different realized and proposed techniques for creating gauge potentials-both Abelian and non-Abelian-in atomic systems and discuss their implication in the context of quantum simulation. While most of these setups concern the realization of background and classical gauge potentials, we conclude with more exotic proposals where these synthetic fields might be made dynamical, in view of simulating interacting gauge theories with cold atoms. PMID:25422950
Classification of 6d N=(1,0) gauge theories
Bhardwaj, Lakshya
2015-11-01
We delineate a procedure to classify 6d N=(1,0) gauge theories composed, in part, of a semi-simple gauge group and hypermultiplets. We classify these theories by requiring that satisfy some consistency conditions. The primary consistency condition is that the gauge anomaly can be cancelled by adding tensor multiplets which couple to the gauge fields by acting as sources of instanton strings. Based on the number of tensor multiplets required to cancel the anomaly, we conjecture that the UV completion of these consistent gauge theories (if it exists) should be either a 6d N=(1,0) SCFT or a 6d N=(1,0) little string theory.
Anomaly Structure of Supergravity and Anomaly Cancellation
Butter, Daniel
2009-01-01
We display the full anomaly structure of supergravity, including new D-term contributions to the conformal anomaly. This expression has the super-Weyl and chiral U(1)_K transformation properties that are required for implementation of the Green-Schwarz mechanism for anomaly cancellation. We outline the procedure for full anomaly cancellation. Our results have implications for effective supergravity theories from the weakly coupled heterotic string theory.
Gravitational waves from gravitational collapse
Energy Technology Data Exchange (ETDEWEB)
Fryer, Christopher L [Los Alamos National Laboratory; New, Kimberly C [Los Alamos National Laboratory
2008-01-01
Gravitational wave emission from stellar collapse has been studied for nearly four decades. Current state-of-the-art numerical investigations of collapse include those that use progenitors with more realistic angular momentum profiles, properly treat microphysics issues, account for general relativity, and examine non-axisymmetric effects in three dimensions. Such simulations predict that gravitational waves from various phenomena associated with gravitational collapse could be detectable with ground-based and space-based interferometric observatories. This review covers the entire range of stellar collapse sources of gravitational waves: from the accretion induced collapse of a white dwarf through the collapse down to neutron stars or black holes of massive stars to the collapse of supermassive stars.
Gravitational Waves from Gravitational Collapse
Directory of Open Access Journals (Sweden)
Chris L. Fryer
2011-01-01
Full Text Available Gravitational-wave emission from stellar collapse has been studied for nearly four decades. Current state-of-the-art numerical investigations of collapse include those that use progenitors with more realistic angular momentum profiles, properly treat microphysics issues, account for general relativity, and examine non-axisymmetric effects in three dimensions. Such simulations predict that gravitational waves from various phenomena associated with gravitational collapse could be detectable with ground-based and space-based interferometric observatories. This review covers the entire range of stellar collapse sources of gravitational waves: from the accretion-induced collapse of a white dwarf through the collapse down to neutron stars or black holes of massive stars to the collapse of supermassive stars.
Axionic defect anomalies and their cancellation
International Nuclear Information System (INIS)
We present a simple derivation of the Callan-Harvey-Naculich effect, i.e. the compensation of charge violation on axion strings due to gauge anomalies by accretion of charge onto the string from the surrounding space. We then show, in the case of axion fields without a potential, that an alternative explanation is possible in which no reference to the surrounding space is necessary because the anomalies are cancelled by a version of the Green-Schwarz mechanism. We prove that such an alternative explanation is always possible in the more general context of p-brane defects in d-dimensional field theories, and hence that there always exists an anomaly-free effective world-volume action whenever the space-time theory is anomaly free. Our results have implications, which we discuss, for heterotic and type-II fivebranes. (orig.)
On the fundamental principles of the relativistic theory of gravitation
International Nuclear Information System (INIS)
This paper expounds consistently within the frames of the Special Relativity Theory the fundamental postulates of the Relativistic Theory of Gravitation (RTG) which make it possible to obtain the unique complete system of the equations for gravitational field. Major attention has been paid to the analysis of the gauge group and of the causality principle. Some results related to the evolution of the Friedmann Universe, to gravitational collapse, etc. being the consequences of the RTG equations are also presented. 7 refs
Entanglement Entropy & Anomaly Inflow
Hughes, Taylor L; Parrikar, Onkar; Ramamurthy, Srinidhi T
2015-01-01
We study entanglement entropy for parity-violating (time-reversal breaking) quantum field theories on $\\mathbb{R}^{1,2}$ in the presence of a domain wall between two distinct parity-odd phases. The domain wall hosts a 1+1-dimensional conformal field theory (CFT) with non-trivial chiral central charge. Such a CFT possesses gravitational anomalies. It has been shown recently that, as a consequence, its intrinsic entanglement entropy is sensitive to Lorentz boosts around the entangling surface. Here, we show using various methods that the entanglement entropy of the three-dimensional bulk theory is also sensitive to such boosts owing to parity-violating effects, and that the bulk response to a Lorentz boost precisely cancels the contribution coming from the domain wall CFT. We argue that this can naturally be interpreted as entanglement inflow (i.e., inflow of entanglement entropy analogous to the familiar Callan-Harvey effect) between the bulk and the domain-wall, mediated by the low-lying states in the entangl...
Loup, Fernando
2007-01-01
We use the 5D Extra Dimensional Force according to Basini-Capozziello-Ponce De Leon,Overduin-Wesson and Mashoon-Wesson-Liu Formalisms to study the behaviour of the Chung-Freese Superluminal BraneWorld compared to the Alcubierre Warp Drive and we arrive at some interesting results from the point of view of the Alcubierre ansatz although we used a diferent Shape Function f(rs) with a behaviour similar to the Natario Warp Drive. We introduce here the Casimir Warp Drive. We also demonstrate that in flat 5D Minkowsky Spacetime or weak Gravitational Fields we cannot tell if we live in a 5D or a 4D Universe according to Basini-Capozziello-Ponce De Leon,Overduin-Wesson and Mashoon-Wesson-Liu Dimensional Reduction but in the extreme conditions of Strong Gravitational Fields we demonstrate that the effects of the 5D Extra Dimension becomes visible and perhaps the study of the extreme conditions in Black Holes can tell if we live in a Higher Dimensional Universe. We use a 5D Maartens-Clarkson Schwarzschild Cosmic Black ...
Recent developments in the path integral approach to anomalies
International Nuclear Information System (INIS)
After a brief summary of the path integral approach to anomalous identities, some of the recent developments in this approach are discussed. The topics discussed include (i) Construction of the effective action by means of the covariant current, (ii) Gauss law constraint in anomalous gauge theories, (iii) Path integral approach to anomalies in superconformal transformations, (iv) Conformal and ghost number anomalies in string theory in analogy with the instanton calculation, (v) Covariant local Lorentz anomaly and its connection with the mathematical construction of the consistent anomaly. (author)
Brzezinski, T.; Majid, S.
1996-01-01
We develop a generalised gauge theory in which the role of gauge group is played by a coalgebra and the role of principal bundle by an algebra. The theory provides a unifying point of view which includes quantum group gauge theory, embeddable quantum homogeneous spaces and braided group gauge theory, the latter being introduced now by these means. Examples include ones in which the gauge groups are the braided line and the quantum plane.
Confining gauge theories without Goldstone bosons
International Nuclear Information System (INIS)
We discuss the possibility that in the Wilson lattice definition of confining gauge theories without Goldstone bosons one may systematically adjust the lightest vector mass to zero while keeping the isosinglet scalar mass, which arises by the chiral anomaly, nontachyonic. We discuss a Weyl fermion theory and find the lightest vector particle to be an isoscalar (at least in strong coupling) so that there is no collision with known theorems. We discuss how an abelian gauge symmetry can arise as an infrared attractor and point out a difference between the Weyl fermion theory and one flavour QCD. Attention is also drawn to a physical motivation. (orig.)
Supersymmetric gauge theories from string theory
International Nuclear Information System (INIS)
This thesis presents various ways to construct four-dimensional quantum field theories from string theory. In a first part we study the generation of a supersymmetric Yang-Mills theory, coupled to an adjoint chiral superfield, from type IIB string theory on non-compact Calabi-Yau manifolds, with D-branes wrapping certain sub-cycles. Properties of the gauge theory are then mapped to the geometric structure of the Calabi-Yau space. Even if the Calabi-Yau geometry is too complicated to evaluate the geometric integrals explicitly, one can then always use matrix model perturbation theory to calculate the effective superpotential. The second part of this work covers the generation of four-dimensional super-symmetric gauge theories, carrying several important characteristic features of the standard model, from compactifications of eleven-dimensional supergravity on G2-manifolds. If the latter contain conical singularities, chiral fermions are present in the four-dimensional gauge theory, which potentially lead to anomalies. We show that, locally at each singularity, these anomalies are cancelled by the non-invariance of the classical action through a mechanism called 'anomaly inflow'. Unfortunately, no explicit metric of a compact G2-manifold is known. Here we construct families of metrics on compact weak G2-manifolds, which contain two conical singularities. Weak G2-manifolds have properties that are similar to the ones of proper G2-manifolds, and hence the explicit examples might be useful to better understand the generic situation. Finally, we reconsider the relation between eleven-dimensional supergravity and the E8 x E8-heterotic string. This is done by carefully studying the anomalies that appear if the supergravity theory is formulated on a ten-manifold times the interval. Again we find that the anomalies cancel locally at the boundaries of the interval through anomaly inflow, provided one suitably modifies the classical action. (author)
Cosmic strings in a product Abelian gauge field theory
International Nuclear Information System (INIS)
It is shown that multiply distributed cosmic strings arise in the product Abelian gauge field theory of Tong and Wong where vortices generated from an extra gauge sector are used to realize magnetic impurities. It is seen that, in view of the fully coupled Einstein and gauge-matter equations, the presence of such cosmic strings in the form of topological defects is essential for gravitation. Asymptotic behavior of the string solutions can be precisely described to allow the derivation of a necessary and sufficient condition for the gravitational metric to be geodesically complete and an explicit calculation of the deficit angle proportional to the string tension, both stated in terms of string numbers, energy levels of broken symmetries, and the universal gravitational constant
Gauge field theories. I : Gauge fields, Goldstone theorem and Higgs phenomena
International Nuclear Information System (INIS)
This lecture on gauge field theories is presented in six sections. In Section I, some general features of the gauge field theories are considered. The simple example of electrodynamics is studied in detail. The minimal electromagnetic interaction; one parameter gauge theory, the non-Abelian gauge groups; Yang-Mills fields and the Universality of gauge field couplings are discussed. In Section II, the various problems that arise in the dynamics of Yang-Mills fields at classical and quantum level are discussed. Included in the discussion are : Field equations and identities, Canonical formalism, Quantization, and Mass of the gauge field quanta. In Section III, spontaneous symmetry breaking is discussed in the context of field theory. Goldstone theorom is clearly stated, proved and illustrated by simple examples. Goldstone quanta are explained. In Section IV, the Higg's phenomenon concerning Goldstone bosons and massless particles is studied in detail in the Abelian and non-Abelian Gauge formalisms. The working of the Higgs-Kibble mechanism is illustrated with examples. In Section V, the Weinberg-Salam model on the unification of weak and electromagnetic interactions of leptons, based on Higgs-Kibble mechanism is discussed in relation to electron type leptons. In the last Section VI, some aspects of spontaneously broken gauge theories connected with renormalizability are discussed. These include (a) high energy behaviour of tree graphs, (b) self-masses, (c) the anomaly problem, and (d) the safe algebra. (A.K.)
Introduction to noncovariant gauges
International Nuclear Information System (INIS)
The most important single attribute of noncovariant gauges is their ghost-free nature. Although noncovariant gauges have been an integral part of quantum field theory for many decades, their effectiveness in the quantization of non-Abelian theories and their broad range of applicability have only recently been appreciated by theorists at large. The purpose of this review is to explain and illustrate the essential characteristics of some typical noncovariant gauges, such as the axial gauge, the planar gauge, the light-cone gauge, and the temporal gauge. The author's aim is to acquaint the reader not only with the basic properties of these ghost-free gauges, but also with their deficiencies and advantages over covariant gauges, their computational idiosyncrasies, and their dominant areas of application
Footprints of New Strong Dynamics via Anomaly
Nakai, Yuichiro; Tobioka, Kohsaku
2015-01-01
Chiral anomaly provides a smoking-gun evidence of a new confining gauge theory. Motivated by a reported event excess in diphoton invariant mass distribution at the LHC, we discuss a scenario that a pseudo-Nambu-Goldstone (pNG) boson of a new QCD-like theory is produced by gluon fusion and decays into a pair of the standard model gauge bosons. Despite the strong dynamics, the production cross section and the decay widths are determined by anomaly matching condition. The excess can be explained by the pNG boson with mass of around 750 GeV. The model also predicts exotic hadrons such as a color octet scalar and baryons which are within the reach of the LHC experiment.
Chiral anomalies and differential geometry
Energy Technology Data Exchange (ETDEWEB)
Zumino, B.
1983-10-01
Some properties of chiral anomalies are described from a geometric point of view. Topics include chiral anomalies and differential forms, transformation properties of the anomalies, identification and use of the anomalies, and normalization of the anomalies. 22 references. (WHK)
Chiral anomalies and differential geometry
International Nuclear Information System (INIS)
Some properties of chiral anomalies are described from a geometric point of view. Topics include chiral anomalies and differential forms, transformation properties of the anomalies, identification and use of the anomalies, and normalization of the anomalies. 22 references
Schwarzschild Space-Time in Gauge Theories of Gravity
Kawai, Toshiharu; Sakane, Eisaku; Tojo, Takashi
1998-01-01
In Poincar\\'e gauge theory of gravity and in $\\overline{\\mbox{Poincar\\'e}}$ gauge theory of gravity, we give the necessary and sufficient condition in order that the Schwarzschild space-time expressed in terms of the Schwarzschild coordinates is obtainable as a torsionless exact solution of gravitational field equations with a spinless point-like source having the energy-momentum density $\\widetilde{\\mbox{\\boldmath $T$}}_\\mu^{~\
Pioneer Anomaly in Perturbed FRW Metric
Shojaie, Hossein
2012-01-01
In this manuscript, it is shown that the Pioneer anomaly is the local evidence for an expanding universe. In other words, its value is a direct measure of the Hubble constant while its sign shows the expanding behavior of the dynamics of the universe. This analysis is obtained by studying the radial geodesic deviation of the light rays in the perturbed Friedmann-Robertson-Walker metric in the Newtonian gauge.
Anomaly extraction from the path integral
International Nuclear Information System (INIS)
Fujikawa's recently proposed derivation of the anomaly from the path integral is examined. It is attempted to give a better understanding of his work. In particular, evasions of his result are discussed; for example it is shown how chiral U(1) axial invariance can be maintained by employing a gauge variant regularization prescription. A brief connection with the point-splitting method is also made. (author)
Implementing Mach's principle using gauge theory
International Nuclear Information System (INIS)
We reformulate an approach fist given by Barbour and Bertotti (BB) for implementing Mach's principle for nonrelativistic particles. This reformulation can deal with arbitrary symmetry groups and finite group elements. Applying these techniques to U(1) and SU(N) invariant scalar field theories, we show that BB's proposal is nearly equivalent to defining a covariant derivative using a dynamical connection. We then propose a modified version of the BB method which implements Mach's principle using gauge theory techniques and argue that this modified method is equivalent to the original. Given this connection between the particle models and Yang-Mills theories, we consider the effect of dynamic curvature as a possible generalization of the BB scheme. Since the BB method can be used as a novel way of deriving geometrodynamics, the connection with gauge theory may shed new light on the gauge properties of the gravitational field.
The Hawking effect in abelian gauge theories
International Nuclear Information System (INIS)
In an effort to compare and contrast gravity with other field theories an investigation is made into whether the Hawking effect is a peculiarly gravitational phenomenon. It is found that the effect exists for a particular background abelian gauge field configuration, as well as certain background gravitational field configurations. Specifically, pair production in a uniform electric field is shown to admit a thermal interpretation. In an effort to find out just what is singular about gravity it is found that the Hawking temperature characteristic of a particular gravitational field configuration is independent of the properties of the quantum fields propagating theorem, in direct contrast to the gauge field case. This implies that if the one loop approximation is to be valid the electric field must be ''cold'' relative to the energy scales set by the quantum fields. In gravity, however, because of the existence of a fundamental scale, the Planck length, the gravitational field can be ''hot'' or ''cold'' and a one loop approximation still remain valid. copyright 1989 Academic Press, Inc
Gravitational Radiation from Oscillating Gravitational Dipole
De Aquino, Fran
2002-01-01
The concept of Gravitational Dipole is introduced starting from the recent discovery of negative gravitational mass (gr-qc/0005107 and physics/0205089). A simple experiment, a gravitational wave transmitter, to test this new concept of gravitational radiation source is presented.
Topological anomalies for Seifert 3-manifolds
Imbimbo, Camillo
2014-01-01
We study globally supersymmetric 3d gauge theories on curved manifolds by describing the coupling of 3d topological gauge theories, with both Yang-Mills and Chern-Simons terms in the action, to background topological gravity. In our approach the Seifert condition for manifolds supporting global supersymmetry is elegantly deduced from the topological gravity BRST transformations. A cohomological characterization of the geometrical moduli which affect the partition function is obtained. In the Seifert context Chern-Simons topological (framing) anomaly is BRST trivial. We compute explicitly the corresponding local Wess-Zumino functional. As an application, we obtain the dependence on the Seifert moduli of the partition function of 3d supersymmetric gauge theory on the squashed sphere by solving the anomalous topological Ward identities, in a regularization independent way and without the need of evaluating any functional determinant.
Energy Momentum Pseudo-Tensor of Relic Gravitational Wave in Expanding Universe
Su, Daiqin; Zhang, Yang
2012-01-01
We study the energy-momentum pseudo-tensor of gravitational wave, and examine the one introduced by Landau-Lifshitz for a general gravitational field and the effective one recently used in literature. In short wavelength limit after Brill-Hartle average, both lead to the same gauge invariant stress tensor of gravitational wave. For relic gravitational waves in the expanding universe, we examine two forms of pressure, $p_{gw}$ and $\\mathcal{P}_{gw}$, and trace the origin of t...
Ciufolini, I; Moschella, U; Fre, P
2001-01-01
Gravitational waves (GWs) are a hot topic and promise to play a central role in astrophysics, cosmology, and theoretical physics. Technological developments have led us to the brink of their direct observation, which could become a reality in the coming years. The direct observation of GWs will open an entirely new field: GW astronomy. This is expected to bring a revolution in our knowledge of the universe by allowing the observation of previously unseen phenomena, such as the coalescence of compact objects (neutron stars and black holes), the fall of stars into supermassive black holes, stellar core collapses, big-bang relics, and the new and unexpected.With a wide range of contributions by leading scientists in the field, Gravitational Waves covers topics such as the basics of GWs, various advanced topics, GW detectors, astrophysics of GW sources, numerical applications, and several recent theoretical developments. The material is written at a level suitable for postgraduate students entering the field.
Pansart, Jean Pierre
2016-01-01
Gauge fields associated to the Dirac matrix algebra used with the standard quadratic gauge field Lagrangian lead to an extended gravitational Lagrangian which includes the Einstein-Hilbert one, plus quadratic, cosmological constant and torsion terms. This note looks at three cases : the static central symmetric field, the isotropic expanding universe, and the asymptotic field of a rotating body, and show that, in weak gravitational fields, there is no contradiction with General Relativity results.
Sluse, D; Magain, P; Courbin, F; Meylan, G
2011-01-01
(abridged) Gravitationally lensed quasars can be used as powerful cosmological and astrophysical probes. We can (i) infer the Hubble constant based on the time-delay technique, (ii) unveil substructures along the l.o.s. toward distant galaxies, and (iii) compare the shape and the slope of baryons and dark matter distributions in galaxies. To reach these goals, we need high-accuracy astrometry and morphology measurements of the lens. In this work, we first present new astrometry for 11 lenses with measured time delays. Using MCS deconvolution on NIC2 HST images, we reached an astrometric accuracy of about 1-2.5 mas and an accurate shape measurement of the lens galaxy. Second, we combined these measurements with those of 14 other systems to present new mass models of these lenses. This led to the following results: 1) In 4 double-image quasars, we show that the influence of the lens environment on the time delay can easily be quantified and modeled, hence putting these lenses with high priority for time-delay d...
Anomalies in non-polynomial closed string field theory
Energy Technology Data Exchange (ETDEWEB)
Kaku, Michio (Institute for Advanced Study, Princeton, NJ (USA))
1990-11-01
The complete classical action for the non-polynomial closed string field theory was written down last year by the author and the Kyoto group. It successfully reproduces all closed string tree diagrams, but fails to reproduce modular invariant loop amplitudes. In this paper we show that the classical action is also riddled with gauge anomalies. Thus, the classical action is not really gauge invariant and fails as a quantum theory. The presence of gauge anomalies and the violation of modular invariance appear to be a disaster for the theory. Actually, this is a blessing in disguise. We show that by adding new non-polynomial terms to the action, we can simultaneously eliminate both the gauge anomalies and the modular-violating loop diagrams. We show this explicitly at the one loop level and also for an infinite class of p-puncture, genus-g amplitudes, making use of a series of non-trivial identities. The theory is thus an acceptable quantum theory. We comment on the origin of this strange link between local gauge anomalies and global modular invariance. (orig.).
Stringy explanation of $b \\to s \\ell^+ \\ell^-$ anomalies
Celis, Alejandro; Lust, Dieter
2015-01-01
We show that the recent anomalies in $b \\to s \\ell^+ \\ell^-$ transitions observed by the LHCb collaboration can be accommodated within string motivated models with a low mass $Z^{\\prime}$ gauge boson. Such $Z^{\\prime}$ gauge boson can be obtained in compactifications with a low string scale. We consider a class of intersecting D-brane models, in which different families of quarks and leptons are simultaneously realized at different D-brane intersections. The explanation of $b \\to s \\ell^+ \\ell^-$ anomalies via a stringy $Z^{\\prime}$ sets important restrictions on these viable D-brane constructions.
Astrometric Solar-System Anomalies
Anderson, John D.
2009-05-01
There are four unexplained anomalies connected with astrometric data. Perhaps the most disturbing is the fact that when a spacecraft on a flyby trajectory approaches the Earth within 2000 km or less, it experiences a gain in total orbital energy per unit mass (Anderson et al., Phys. Rev. Lett. 100, 091102). This amounts to a net velocity increase of 13.5 mm/s for the NEAR spacecraft at a closest approach of 539 km, 3.9 mm/s for the Galileo spacecraft at 960 km, and 1.8 mm/s for the Rosetta spacecraft at 1956 km. Next, I suggest the change in the astronomical unit AU is definitely a concern. It is increasing by about 15 cm/yr (Krasinsky and Brumberg, Celes. Mech. & Dynam. Astron. 90, 267). The other two anomalies are perhaps less disturbing because of known sources of nongravitational acceleration. The first is an apparent slowing of the two Pioneer spacecraft as they exit the solar system in opposite directions (Anderson et al., Phys. Rev. D 65, 082004). Some, including me, are convinced this effect is of concern, but many are convinced it is produced by a nearly identical thermal emission from both spacecraft, in a direction away from the Sun, thereby producing acceleration toward the Sun. The fourth anomaly is a measured increase in the eccentricity of the Moon's orbit. Here again, an increase is expected from tidal friction in both the Earth and Moon. However, there is a reported increase that is about three times larger than expected (J. G. Williams, DDA/AAS Brouwer Award Lecture, Halifax, Nova Scotia 2006). We suspect that all four anomalies have mundane explanations. However, the possibility that they will be explained by a new theory of gravitation is not ruled out, perhaps analogous to Einstein's 1916 explanation of the excess precession of Mercury's perihelion.
Goon, Garrett; Hinterbichler, Kurt; Joyce, Austin; Trodden, Mark
2011-01-01
We show how the coupling of SO(N) gauge fields to galileons arises from a probe brane construction. The galileons arise from the brane bending modes of a brane probing a co-dimension N bulk, and the gauge fields arise by turning on certain off-diagonal components in the zero mode of the bulk metric. By construction, the equations of motion for both the galileons and gauge fields remain second order. Covariant gauged galileons are derived as well.
Energy Technology Data Exchange (ETDEWEB)
Goon, Garrett L.; Hinterbichler, Kurt [Center for Particle Cosmology, Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104 (United States); Joyce, Austin, E-mail: joyceau@sas.upenn.edu [Center for Particle Cosmology, Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104 (United States); Trodden, Mark [Center for Particle Cosmology, Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104 (United States)
2012-07-24
We show how the coupling of SO(N) gauge fields to galileons arises from a probe brane construction. The galileons arise from the brane bending modes of a brane probing a co-dimension N bulk, and the gauge fields arise by turning on certain off-diagonal components in the zero mode of the bulk metric. By construction, the equations of motion for both the galileons and gauge fields remain second order. Covariant gauged galileons are derived as well.
Electroweak phase transition in a model with gauged lepton number
Aranda, Alfredo; Jiménez, Enrique; Vaquera-Araujo, Carlos A.
2015-01-01
In this work we study the electroweak phase transition in a model with gauged lepton number. Here, a family of vector-like leptons is required in order to cancel the gauge anomalies. Furthermore, these leptons can play an important role in the transition process. We find that this framework is able to provide a strong transition, but only for a very limited number of cases.
Supersymmetry breaking from superstrings and the gauge hierarchy
International Nuclear Information System (INIS)
The gauge hierarchy problem is reviewed and a class of effective field theories obtained from superstrings is described. These are characterized by a classical symmetry, related to the space-time duality of string theory, that is responsible for the suppression of observable supersymmetry breaking effects. At the quantum level, the symmetry is broken by anomalies that provide the seed of observable supersymmetry breaking, and an acceptably large gauge hierarchy may be generated. 39 refs
Duality of Chiral N=1 Supersymmetric Gauge Theories via Branes
Landsteiner, K; Lowe, D A; Landsteiner, Karl; Lopez, Esperanza; Lowe, David A.
1998-01-01
Using a six-orientifold on top of a NS-fivebrane we construct a chiral N=1 supersymmetric gauge theory in four dimensions with gauge group SU(N_c) and matter in the symmetric, antisymmetric and (anti)fundamental representations. Anomaly cancellation is fulfilled by the requirement of a smooth RR 7-form charge distribution and leads us to the introduction of 8 half D-sixbranes ending on the NS-fivebrane. We obtain the dual model from branes by a linking number argument. We check explicitly the 't Hooft anomaly matching conditions and the map between deformations in the original and the dual model.
Faber, M.; Greensite, J.; Olejnik, S.
2001-01-01
We introduce a variation of direct maximal center gauge fixing: the ``direct Laplacian'' center gauge. The new procedure overcomes certain shortcomings of maximal center gauge, associated with Gribov copies, that were pointed out by Bornyakov et al. in hep-lat/0009035.
International Nuclear Information System (INIS)
A method of the construction of the superfield normal gauge in the vicinity of a fixed point is given. In order to construct gauge-invariant theoretical quantities the question on the normal gauge application to the supergravity theory is discussed
The ? transformation and gravitational copies
International Nuclear Information System (INIS)
An Abelian symmetry already considered by Einstein with respect to his asymmetrical field theories is related to the gravitational and gauge field copy phenomenon. It is shown that gauge field copies arise out of a straightforward generalization of the ? - map. The connection between Einstein's work on the ?-transformation and the copy phenomenon is obtained with the help of the Frobenius Theorem on the existence of foliations on a differentiable manifold. A problem like the one above is usually treated within the language of (intrinsic) Differential Geometry; General Relativity and classical unified field theories are traditionally developed in a classical style, that gap, a long introduction is prepared where the same structures are studied from the traditional and from the more recent point of view. (author)
Understanding Anomalies to Extract Vacuum Energy
International Nuclear Information System (INIS)
Recent Russian literature contains some interesting speculations of potentially wide applicability regarding the physical vacuum. These investigations examined and applied a theory to various anomalies to try and understand what these events may represent. Data were collected by Dmitriev to quantify these events and identify commonalties that indicate the anomalies might have a natural origin. Dyatlov created theories on the Polarized Inhomogeneous Physical Vacuum where he claimed that each anomaly possessed a distinct boundary separate from its surroundings. Within this inhomogeneous boundary, the theory suggests that the magnetic, electric, gravitic, and spin fields would be different from its surroundings. From these findings, he developed equations that resemble the London equations for a superconductor and are somewhat similar to those developed later by Puthoff. The importance of these events is that with additional understanding, they may offer a means for extracting energy from the physical vacuum. Moreover, one may speculate that these anomalies may represent a gravitational vortex or even a portal or a wormhole to look into potential travel within other dimensions
Reformulation of Einstein gravity as a flat space gauge theory
International Nuclear Information System (INIS)
Based on an algebraic decomposition of a fourth rank tensor in terms of second rank tensors the authors suggest a reformulation of Einstein's gravitational theory as a flat space gauge theory. This has been done by associating a curved manifold with a flat space U(2) X U(2) gauge theory. It is shown that while, in order to reproduce Einstein field equations one has to use a non-Yang-Mills action, the linearized equations follow from a Yang-Mills action. A relation between the metric and gauge fields is obtained. The consistency of the postulates is also verified
Mansouri-Chang gravitation theory
International Nuclear Information System (INIS)
I examine the new gauge theory of gravitation theory proposed recently by Mansouri and Chang. It appears that the predictions of the theory are indistinguishable from those of general relativity with regard to the usual tests. With the aid of the symbolic manipulation computer system, MACSYMA, I find that the theory possesses a remarkable similarity to Einstein's theory with respect to vacuum solutions. While the field equations are greatly different, a question arises whether there are any solutions of the new equations which are not Einstein vacuum spaces
Pioneer Anomaly and the Kuiper Belt mass distribution
Bertolami, O.; Vieira, P
2005-01-01
Pioneer 10 and 11 were the first probes sent to study the outer planets of the Solar System and Pioneer 10 was the first spacecraft to leave the Solar System. Besides their already epic journeys, Pioneer 10 and 11 spacecraft were subjected to an unaccounted effect interpreted as a constant acceleration toward the Sun, the so-called Pioneer anomaly. One of the possibilities put forward for explaining the Pioneer anomaly is the gravitational acceleration of the Kuiper Belt. In...
2015-11-04
Lymphatic Malformation; Generalized Lymphatic Anomaly (GLA); Central Conducting Lymphatic Anomaly; CLOVES Syndrome; Gorham-Stout Disease ("Disappearing Bone Disease"); Blue Rubber Bleb Nevus Syndrome; Kaposiform Lymphangiomatosis; Kaposiform Hemangioendothelioma/Tufted Angioma; Klippel-Trenaunay Syndrome; Lymphangiomatosis
Massive graviton and determination of cosmological constant from gauge theory of gravity
International Nuclear Information System (INIS)
The universe contains a lot more than the eye meets . Sophisticated experiments search diligently for this invisible dark matter. Here we will describe some theoretical implications of the gravitational gauge theory recently proposed by Ning Wu (hep-th/0112062), namely the possibility of the existence of massive gravitons which fill the intergalactic space. Dark matter is an important problem in cosmology. In gravitational gauge field theory, the following effects should be taken into account to solve this problem: 1) The existence of massive graviton will have some contribution to the dark matter; 2) If the gravitational magnetic field is strong inside a celestial system, the gravitational Lorentz force will provide additional centripetal force for circular motion of a celestial object; 3) The existence of a factor which violate inverse square law of classical gravity. Combining general relativity and gravitational gauge theory the cosmological constant is determined theoretically. The cosmological constant is related to the average vacuum energy of the gravitational gauge field. Because the vacuum energy of the gravitational gauge field is negative, the cosmological constant is positive what generates repulsive force on stars to make the expansion rate of the Universe accelerated. A rough estimation of it gives out its magnitude order 10-52 m-2, which is well consistent with experimental results. (authors)
Fermions with a domain-wall mass: explicit Greens function and anomaly cancellation
Energy Technology Data Exchange (ETDEWEB)
Chandrasekharan, S. (Dept. of Physics, Columbia Univ., New York, NY (United States))
1994-04-01
We calculate the explicit Greens function for fermions in 2+1 dimensions, with a domain wall mass. We then show a calculation demonstrating the anomaly cancellation when such fermions move in the background of an abelian gauge field. (orig.)
Fermions with a domain-wall mass: explicit Greens function and anomaly cancellation
International Nuclear Information System (INIS)
We calculate the explicit Greens function for fermions in 2+1 dimensions, with a domain wall mass. We then show a calculation demonstrating the anomaly cancellation when such fermions move in the background of an abelian gauge field. (orig.)
Arraut, Ivan(Theory Center, Institute of Particle and Nuclear Studies, KEK Tsukuba, Ibaraki 305-0801, Japan)
2012-01-01
We analyze the propagation of gravitational waves (GWs) in an asymptotically de-Sitter space by expanding the perturbation around Minkowski and introducing the effects of the Cosmological Constant ($\\Lambda$), first as an additional source (de-Donder gauge) and after as a gauge effect ($\\Lambda$-gauge). In both cases the inclusion of the Cosmological Constant $\\Lambda$ impedes the detection of a gravitational wave at a distance larger than $L_{crit}=(6\\sqrt{2}\\pi f \\hat{h}/\\...
ALT_TIDE_GAUGE_L4_OST_SLA_US_WEST_COAST:1
National Aeronautics and Space Administration — This data set contains sea level anomalies and alongshore ocean currents (U and V) derived from satellite altimeters and tide gauge data. Currents and heights near...
Improved Moving Puncture Gauge Conditions for Compact Binary Evolutions
Etienne, Zachariah B.; Baker, John G.; Paschalidis, Vasileios; Kelly, Bernard J.; Shapiro, Stuart L.
2014-01-01
Robust gauge conditions are critically important to the stability and accuracy of numerical relativity (NR) simulations involving compact objects. Most of the NR community use the highly robust-though decade-old-moving-puncture (MP) gauge conditions for such simulations. It has been argued that in binary black hole evolutions adopting this gauge, noise generated near adaptive-mesh-refinement (AMR) boundaries does not converge away cleanly with increasing resolution, severely limiting gravitational waveform accuracy at computationally feasible resolutions. We link this noise to a sharp (short-wavelength), initial outgoing gauge wave crossing into progressively lower resolution AMR grids and present improvements to the standard MP gauge conditions that focus on stretching, smoothing, and more rapidly settling this outgoing wave. Our best gauge choice greatly reduces gravitational waveform noise during inspiral, yielding less fluctuation in convergence order and approx. 40% lower waveform phase and amplitude errors at typical resolutions. Noise in other physical quantities of interest is also reduced, and constraint violations drop by more than an order of magnitude. We expect these improvements will carry over to simulations of all types of compact binary systems, as well as other N + 1 formulations of gravity for which MP-like gauge conditions can be chosen.
Running couplings in quantum theory of gravity coupled with gauge fields
Narain, Gaurav; Anishetty, Ramesh
2013-10-01
In this paper we study the coupled system of non-abelian gauge fields with higher-derivative gravity. Charge renormalization is investigated in this coupled system. It is found that the leading term in the gauge coupling beta function comes due to interaction of gauge fields with gravitons. This is shown to be a universal quantity in the sense that it doesn't depend on the gauge coupling and the gauge group, but may depend on the other couplings of the action (gravitational and matter). The coupled system is studied at one-loop. It is found that the leading term of gauge beta function is zero at one-loop in four dimensions. The effect of gauge fields on the running of gravitational couplings is investigated. The coupled system of gauge field with higher-derivative gravity is shown to satisfy unitarity when quantum corrections are taken in to account. Moreover, it is found that Newton constant goes to zero at short distances. In this renormalizable and unitary theory of gauge field coupled with higher-derivative gravity, the leading term of the gauge beta function, found to be universal for all gauge groups, is further studied in more detail by isolating it in the context of abelian gauge theories coupled with gravity in four dimensions. Using self-duality of abelian gauge theories in four dimensions, this term of the gauge beta function is shown to be zero to all loops. This is found to be independent of the gravity action, regularization scheme and gauge fixing condition. An explicit one-loop computation for arbitrary gravity action further demonstrates the vanishing of this term in the gauge beta function in four dimensions, independent of the regularization scheme and gauge fixing condition. Consequences of this are discussed.
Gravity duals of supersymmetric gauge theories on three-manifolds
Farquet, Daniel; Martelli, Dario; Sparks, James
2014-01-01
We study gravity duals to a broad class of N=2 supersymmetric gauge theories defined on a general class of three-manifold geometries. The gravity backgrounds are based on Euclidean self-dual solutions to four-dimensional gauged supergravity. As well as constructing new examples, we prove in general that for solutions defined on the four-ball the gravitational free energy depends only on the supersymmetric Killing vector, finding a simple closed formula when the solution has U(1) x U(1) symmetry. Our result agrees with the large N limit of the free energy of the dual gauge theory, computed using localization. This constitutes an exact check of the gauge/gravity correspondence for a very broad class of gauge theories with a large N limit, defined on a general class of background three-manifold geometries.
Canonical quantization and cosmological particle production in non-Abelian gauge theories
International Nuclear Information System (INIS)
A canonical quantization scheme for nonabelian gauge fields in an external, classical gravitational field is formulated and applied to the problem of cosmological Higgs and gauge boson production. Via interaction, the mass of the Higgs field not only leads to additional Higgs production, but also enables the production of massless bosons
Gauge Gravity: a forward-looking introduction
Randono, Andrew
2010-01-01
This article is a review of modern approaches to gravity that treat the gravitational interaction as a type of gauge theory. The purpose of the article is twofold. First, it is written in a colloquial style and is intended to be a pedagogical introduction to the gauge approach to gravity. I begin with a review of the Einstein-Cartan formulation of gravity, move on to the Macdowell-Mansouri approach, then show how gravity can be viewed as the symmetry broken phase of an (A)dS-gauge theory. This covers roughly the first half of the article. Armed with these tools, the remainder of the article is geared toward new insights and new lines of research that can be gained by viewing gravity from this perspective. Drawing from familiar concepts from the symmetry broken gauge theories of the standard model, we show how the topological structure of the gauge group allows for an infinite class of new solutions to the Einstein-Cartan field equations that can be thought of as degenerate ground states of the theory. We argu...
Directory of Open Access Journals (Sweden)
Metin SALTIK
1996-03-01
Full Text Available According to classical electromagnetic theory, an accelerated charge or system of charges radiates electromagnetic waves. In a radio transmitter antenna charges are accelerated along the antenna and release electromagnetic waves, which is radiated at the velocity of light in the surrounding medium. All of the radio transmitters work on this principle today. In this study an analogy is established between the principles by which accelerated charge systems markes radiation and the accelerated mass system, and the systems cousing gravitational radiation are investigated.
Gamma rays and positrons from a decaying hidden gauge boson
Chen, Chuan-Ren; Takahashi, Fuminobu(Department of Physics, Tohoku University, Sendai, 980-8578, Japan); Yanagida, T. T.
2008-01-01
We study a scenario that a hidden gauge boson constitutes the dominant component of dark matter and decays into the standard model particles through a gauge kinetic mixing. Interestingly, gamma rays and positrons produced from the decay of hidden gauge boson can explain both the EGRET excess of diffuse gamma rays and the HEAT anomaly in the positron fraction. The spectra of the gamma rays and the positrons have distinctive features; the absence of line emission of the gamma ray and a sharp pe...
Applications of noncovariant gauges in the algebraic renormalization procedure
Boresch, A; Schweda, Manfred
1998-01-01
This volume is a natural continuation of the book Algebraic Renormalization, Perturbative Renormalization, Symmetries and Anomalies, by O Piguet and S P Sorella, with the aim of applying the algebraic renormalization procedure to gauge field models quantized in nonstandard gauges. The main ingredient of the algebraic renormalization program is the quantum action principle, which allows one to control in a unique manner the breaking of a symmetry induced by a noninvariant subtraction scheme. In particular, the volume studies in-depth the following quantized gauge field models: QED, Yang-Mills t
Gauge theories, black hole evaporation and cosmic censorship
International Nuclear Information System (INIS)
Recent work of Linde, which suggests that gauge theories modify the effective gravitational constant, are applied to the theory of black hole evaporation. Considerable modification of the late stages of evaporation are predicted. Contrary to expectations, the black hole never attains a sufficient temperature to enter the antigravity regime, which would represent a failure of cosmic censorship. (orig.)
Non-abelian discrete gauge symmetries and inflation
Cohn, J. D.; Stewart, E. D.
2000-01-01
Obtaining a potential flat enough to provide slow roll inflation is often difficult when gravitational effects are included. Non-abelian discrete gauge symmetries can guarantee the flatness of the inflaton potential in this case, and also provide special field values where inflation can end.
Yang-Mills Origin of Gravitational Symmetries
Anastasiou, A.; Borsten, L.; Duff, M. J.; Hughes, L. J.; Nagy, S.
2014-12-01
By regarding gravity as the convolution of left and right Yang-Mills theories together with a spectator scalar field in the biadjoint representation, we derive in linearized approximation, the gravitational symmetries of general covariance, p -form gauge invariance, local Lorentz invariance, and local supersymmetry from the flat space Yang-Mills symmetries of local gauge invariance and global super-Poincaré symmetry. As a concrete example, we focus on the new minimal (12 +12 ) off shell version of simple four-dimensional supergravity obtained by tensoring the off shell Yang-Mills multiplets (4 +4 , NL=1 ) and (3 +0 , NR=0 ).
Yang-Mills origin of gravitational symmetries
Anastasiou, A; Duff, M J; Hughes, L J; Nagy, S
2014-01-01
By regarding gravity as the convolution of left and right Yang-Mills theories, we derive in linearised approximation the gravitational symmetries of general covariance, p-form gauge invariance, local Lorentz invariance and local supersymmetry from the flat space Yang-Mills symmetries of local gauge invariance and global super-Poincar\\'e. As a concrete example we focus on the new-minimal (12+12) off-shell version of simple four-dimensional supergravity obtained by tensoring the off-shell Yang-Mills multiplets (4 + 4, N_L = 1) and (3 + 0, N_R = 0).
On the covariant gauge {alpha} of the linearized gravity in de Sitter spacetime
Energy Technology Data Exchange (ETDEWEB)
Cheong, Lee Yen [Department of Fundamental and Applied Science Universiti Teknologi Petronas, Bandar Seri Iskandar, 31750 Tronoh, Perak (Malaysia)
2012-09-26
In previous work, we studied the linearized gravity with covariant gauge {beta}= 2/3 and {alpha}= 5/3. It was found that the sum of the source and initial contributions reproduces the correct field configuration over the whole de Sitter spacetime. In this paper, we extend this work to generalizing the linearized gravitational field in an arbitrary value of the gauge parameter {alpha} but the gauge parameter {beta} remains the same.
On the covariant gauge ? of the linearized gravity in de Sitter spacetime
International Nuclear Information System (INIS)
In previous work, we studied the linearized gravity with covariant gauge ?= 2/3 and ?= 5/3. It was found that the sum of the source and initial contributions reproduces the correct field configuration over the whole de Sitter spacetime. In this paper, we extend this work to generalizing the linearized gravitational field in an arbitrary value of the gauge parameter ? but the gauge parameter ? remains the same.
Kok, P; Kok, Pieter; Yurtsever, Ulvi
2003-01-01
We investigate the effect of quantum metric fluctuations on qubits that are gravitationally coupled to a background spacetime. In our first example, we study the propagation of a qubit in flat spacetime whose metric is subject to flat quantum fluctuations with a Gaussian spectrum. We find that these fluctuations cause two changes in the state of the qubit: they lead to a phase drift, as well as the expected exponential suppression (decoherence) of the off-diagonal terms in the density matrix. Secondly, we calculate the decoherence of a qubit in a circular orbit around a Schwarzschild black hole. The no-hair theorems suggest a quantum state for the metric in which the black hole's mass fluctuates with a thermal spectrum at the Hawking temperature. Again, we find that the orbiting qubit undergoes decoherence and a phase drift that both depend on the temperature of the black hole. Thirdly, we study the interaction of coherent and squeezed gravitational waves with a qubit in uniform motion. Finally, we investigat...
Elliptic operators in the functional quantisation for gauge field theories
Energy Technology Data Exchange (ETDEWEB)
Paycha, S. (Strasbourg-1 Univ., 67 (France). Dept. de Mathematiques)
1994-01-01
Given a gauge theory with gauge group G acting on a path space X, G and X being both infinite dimensional manifolds modelled on spaces of sections of vector bundles on a compact riemannian manifold without boundary, it is shown that when the action of G on X is smooth, free and proper, the same ellipticity condition on an operator naturally given by the geometry of the problem yields both the existence of a principal fibre bundle structure induced by the canonical projection [pi]:X [yields] X/G and the existence of the Faddeev-Popov determinant arising in the functional quantisation of the gauge theory. This holds for certain gauge theories with anomalies like bosonic closed string theory in non-critical dimension and also holds for a class of gauge theories which includes Yang-Mills theory. (orig.)
Elliptic operators in the functional quantisation for gauge field theories
International Nuclear Information System (INIS)
Given a gauge theory with gauge group G acting on a path space X, G and X being both infinite dimensional manifolds modelled on spaces of sections of vector bundles on a compact riemannian manifold without boundary, it is shown that when the action of G on X is smooth, free and proper, the same ellipticity condition on an operator naturally given by the geometry of the problem yields both the existence of a principal fibre bundle structure induced by the canonical projection ?:X ? X/G and the existence of the Faddeev-Popov determinant arising in the functional quantisation of the gauge theory. This holds for certain gauge theories with anomalies like bosonic closed string theory in non-critical dimension and also holds for a class of gauge theories which includes Yang-Mills theory. (orig.)
Gauge covariance in non-Abelian gauge theories
International Nuclear Information System (INIS)
Manifestly Lorentz- and gauge-covariant formulation of the canonical Yang-Mills field theory is presented. It is exhibited that a local gauge transformation forms an invariant gauge family to which relevant one-parameter gauges belong. Gauge symmetries prescribed by the theory are realized by combination of a non-Abelian global gauge transformation and an Abelian local gauge transformation. A renormalization scheme is developed in connection with problems inherent in the theory. (author)
Astrometric and Timing Effects of Gravitational Waves from Localized Sources
Kopeikin, S M; Gwinn, C R; Eubanks, T M; Kopeikin, Sergei M.; Schafer, Gerhard; Gwinn, Carl R.
1999-01-01
A consistent approach for an exhaustive solution of the problem of propagation of light rays in the field of gravitational waves emitted by a localized source of gravitational radiation is developed in the first post-Minkowskian and quadrupole approximation of General Relativity. We demonstrate that the equations of light propagation in the retarded gravitational field of an arbitrary localized source emitting quadrupolar gravitational waves can be integrated exactly. The influence of the gravitational field on the light propagation is examined not only in the wave zone but also in cases when light passes through the intermediate and near zones of the source. Explicit analytic expressions for light deflection and integrated time delay (Shapiro effect) are obtained accounting for all possible retardation effects and arbitrary relative locations of the source of gravitational waves, that of light rays, and the observer. It is shown that the ADM and harmonic gauge conditions can both be satisfied simultaneously ...
Gauged BRST symmetry and the occurence of higher cocycles in quantum field theory
International Nuclear Information System (INIS)
The BRST symmetry of Yang Mills theories can be gauged via the introduction of an anticommuting single gauge field. There follows the construction of a local BRST operation which allows an algebraic analysis of the BRST current algebra. This construction provides, in particular, a field theory interpretation of most higher cocycles which accompany the usual chiral anomaly
Generalized Higher Gauge Theory
Ritter, Patricia; Schmidt, Lennart
2015-01-01
We study a generalization of higher gauge theory which makes use of generalized geometry and seems to be closely related to double field theory. The local kinematical data of this theory is captured by morphisms of graded manifolds between the canonical exact Courant Lie 2-algebroid $TM\\oplus T^*M$ over some manifold $M$ and a semistrict gauge Lie 2-algebra. We discuss generalized curvatures and their infinitesimal gauge transformations. Finite gauge transformation as well as global kinematical data are then obtained from principal 2-bundles over 2-spaces. As dynamical principle, we consider first the canonical Chern-Simons action for such a gauge theory. We then show that a previously proposed 3-Lie algebra model for the six-dimensional (2,0) theory is very naturally interpreted as a generalized higher gauge theory.
Dimensional regularization and ?5. The spurious anomalies problem
International Nuclear Information System (INIS)
A change of principles of operation with external diagram pulses ia proposed in dimensional regularization with four-dimensional ?5-matrix. It is shown that in this case for Abelian gauge theories in one-loop approximation false axial anomalies do not appear. 10 refs
Electrodinámica semiclásica, ¿invariante gauge?
Zambrano, D. E.; Sanchez, J.A.; Morales, J.
2014-01-01
: En conocido que cualquier ley física que involucre la interacción electromagnética se puede expresar en términos de los potenciales electrodinámicos generales A y ?, y que dicha ley permanece inalterada al aplicarle las llamasd transformaciones de gauge, es decir, la teoría es invariante gauge. En el presente trabajo analizamos el caso de la electrodinámica clásica, para la cual verificamos la invariancia gauge, en la estructura de la ecuación de Schrödinger y en los valores propios del ham...
International Nuclear Information System (INIS)
We study the phase structure of SU(2) gauge theories at zero and high temperature, with and without scalar matter fields, in terms of the symmetric/broken realization of the remnant gauge symmetry which exists after fixing to Coulomb gauge. The symmetric realization is associated with a linearly rising color Coulomb potential (which we compute numerically), and is a necessary but not sufficient condition for confinement.
Introduction to gauge theories
International Nuclear Information System (INIS)
These lecture notes contain the text of five lectures and a Supplement. The lectures were given at the JINR-CERN School of Physics, Tabor, Czechoslovakia, 5-18 June 1983. The subgect of the lecinvariancetures: gauge of electromagnetic and weak interactions, higgs and supersymmetric particles. The Supplement contains reprints (or excerpts) of some classical papers on gauge invariance by V. Fock, F. London, O. Klein and H. Weyl, in which the concept of gauge invariance was introduced and developed
International Nuclear Information System (INIS)
Nonlocal gauge theories including gravity are considered. It is shown that the introduction of the additional nonlocal interaction makes ?5-anomalous theories meaningful. The introduction of such interaction leads to macrocausal unitary theory, which describes the interaction of massive vector fields with fermion fields. It is shown that nonlocal gauge theories with nonlocal scale ?nl?(1-10) TeV can solve the gauge hierarchy problem. An example of nonlinear grand unified gauge model in which topologically nontrivial finite energy monopole solutions are absent is found
The Wess-Zumino gauge is a 'good' gauge
International Nuclear Information System (INIS)
It is shown, using a recent superfield formulation of Wess-Zumino gauges, that they are 'good' gauges i.e. that they are consistent with translational invariance and hence may be used in effective potential calculations. This contrasts with the SUSY covariant gauge and the SUSY RÎ¾ gauge, which are 'bad' gauges. (orig.)
Tumbling and complementarity in a chiral gauge theory
International Nuclear Information System (INIS)
We consider in detail a chiral SU(N) gauge theory which undergoes multiple tumbling. An extension of the notion of complementarity is used which allows us to deduce the set of massless fermions, in the confining phase of the theory, which we needed for anomaly matching. The likelyhood of this confining phase ever being realized in practice is discussed. (orig.)
Nonplanar anomalies in noncommutative theories and the Green-Schwarz mechanism
International Nuclear Information System (INIS)
We discuss nonplanar anomalies in noncommutative gauge theories. In particular we show that a nonplanar anomaly exists when the external noncommutative momentum is zero and that it leads to a non-conservation of the associated axial charge. In the case of nonplanar local anomalies, a cancellation of the anomaly can be achieved by a Green-Schwarz mechanism. In an example of D3 branes placed on an orbifold singularity that leads to a chiral theory, the mechanism involves twisted RR fields which propagate with zero noncommutative momentum. Global anomalies are not cancelled and, in particular, the decay ?0?2? is allowed. (author)
Quantum Gravitational Bremsstrahlung, Massless versus Massive Gravity
Berchtold, Julian B.; Scharf, Gunter
2007-01-01
The massive spin-2 quantum gauge theory previously developed is applied to calculate gravitational bremsstrahlung. It is shown that this theory is unique and free from defects. In particular, there is no strong coupling if the graviton mass becomes small. The cross sections go over smoothly into the ones of the massless theory in the limit of vanishing graviton mass. The massless cross sections are calculated for the full tensor theory.
The Road to Gravitational S-Duality
Garcia-Compeán, H.; Obregón, O.; Ramirez, C.; Sabido, M.
We overview the road to defining S-duality analogues for non-supersymmetric theories of gravity. The case of pure topological gravity in four dimensions, and, MacDowell-Mansouri gauge theory of gravity are discussed. Three-dimensional dimensional reductions from the topological gravitational sector in four dimensions, enable to recuperate the 2+1 Chern-Simons gravity and the corresponding S-dual theory, from the notion of self-duality in the four-dimensional theory.
Searching for S-duality in Gravitation
García-Compéan, H; Ramírez, C
2000-01-01
We overview some attempts to find S-duality analogues of non-supersymmetric Yang-Mills theory, in the context of gravity theories. The case of MacDowell-Mansouri gauge theory of gravity is discussed. Three-dimensional dimensional reductions from the topological gravitational sector in four dimensions, enable to recuperate the 2+1 Chern-Simons gravity and the corresponding S-dual theory, from the notion of self-duality in the four-dimensional theory.
Holographic Conformal Partial Waves as Gravitational Open Wilson Networks
Bhatta, Atanu; Suryanarayana, Nemani V
2016-01-01
We propose a method to holographically compute the conformal partial waves in any decomposition of correlation functions of primary operators in conformal field theories using open Wilson network operators in the holographic gravitational dual. The Wilson operators are the gravitational ones where gravity is written as a gauge theory in the first order Hilbert-Palatini formalism. We apply this method to compute the global conformal blocks and partial waves in 2d CFTs reproducing many of the known results.
Conformal Anomalies in Hydrodynamics
Eling, Christopher; Theisen, Stefan; Yankielowicz, Shimon
2013-01-01
We study the effect of conformal anomalies on the hydrodynamic description of conformal field theories in four spacetime dimensions. We consider equilibrium curved backgrounds characterized by a time-like Killing vector and construct a local low energy effective action that captures the conformal anomalies. Using as a special background the Rindler spacetime we derive a formula for the effect of the anomaly on the hydrodynamic pressure.
Network Traffic Anomaly Detection
Huang, Hong; Al-Azzawi, Hussein; Brani, Hajar
2014-01-01
This paper presents a tutorial for network anomaly detection, focusing on non-signature-based approaches. Network traffic anomalies are unusual and significant changes in the traffic of a network. Networks play an important role in today's social and economic infrastructures. The security of the network becomes crucial, and network traffic anomaly detection constitutes an important part of network security. In this paper, we present three major approaches to non-signature-ba...
Gebhard, Gernot
2010-01-01
Computing tight WCET bounds in the presence of timing anomalies - found in almost any modern hardware architecture - is a major challenge of timing analysis. In this paper, we renew the discussion about timing anomalies, demonstrating that even simple hardware architectures are prone to timing anomalies. We furthermore complete the list of timing-anomalous cache replacement policies, proving that the most-recently-used replacement policy (MRU) also exhibits a domino effect.
Toward Supervised Anomaly Detection
Goernitz, Nico; Kloft, Marius Micha; Rieck, Konrad; Brefeld, Ulf
2014-01-01
Anomaly detection is being regarded as an unsupervised learning task as anomalies stem from adversarial or unlikely events with unknown distributions. However, the predictive performance of purely unsupervised anomaly detection often fails to match the required detection rates in many tasks and there exists a need for labeled data to guide the model generation. Our first contribution shows that classical semi-supervised approaches, originating from a supervised classifier, a...
Hall viscosity from elastic gauge fields in Dirac crystals
Cortijo, Alberto; Landsteiner, Karl; Vozmediano, María A H
2015-01-01
The combination of Dirac physics and elasticity has been explored at length in graphene where the so--called "elastic gauge fields" have given rise to an entire new field of research and applications: Straintronics. The fact that these elastic fields couple to fermions as the electromagnetic field, implies that many electromagnetic responses will have elastic counterparts not explored before. In this work we will first show that the presence of elastic gauge fields will be the rule rather than the exception in most of the topologically non--trivial materials in two and three dimensions. In particular we will extract the elastic gauge fields associated to the recently observed Weyl semimetals, the "three dimensional graphene". As it is known, quantum electrodynamics suffers from the chiral anomaly whose consequences have been recently explored in matter systems. We will show that, associated to the physics of the anomalies, and as a counterpart of the Hall conductivity, elastic materials will have a Hall visco...
Apparent anomalies in borehole and seafloor gravity measurements
International Nuclear Information System (INIS)
Apparent anomalies observed in borehole and seafloor gravity measurements are shown to be attributable to inaccurate implementation of Newton's gravitational law using inadequate earth models. Corrections due to global and regional lateral density heterogeneity are estimated and are shown to provide a consistent explanation of signature (attractive or repulsive) and magnitude of the apparent anomalies for borehole and seafloor gravity measurements without introducing any speculative non-newtonian forces. The results obtained show clearly that the underground gravity field cannot be used for precision tests of the inverse square law of the gravitational force at short and intermediate ranges until a reliable and accurate earth model is developed. Predictions of the signature of apparent anomalies are given for future borehole and undersea gravity measurements. (orig.)
The Trace Anomaly and Dynamical Vacuum Energy in Cosmology
Mottola, Emil
2010-01-01
The trace anomaly of conformal matter implies the existence of massless scalar poles in physical amplitudes involving the stress-energy tensor. These poles may be described by a local effective action with massless scalar fields, which couple to classical sources, contribute to gravitational scattering processes, and can have long range gravitational effects at macroscopic scales. In an effective field theory approach, the effective action of the anomaly is an infrared relevant term that should be added to the Einstein-Hilbert action of classical General Relativity to take account of macroscopic quantum effects. The additional scalar degrees of freedom contained in this effective action may be understood as responsible for both the Casimir effect in flat spacetime and large quantum backreaction effects at the horizon scale of cosmological spacetimes. These effects of the trace anomaly imply that the cosmological vacuum energy is dynamical, and its value depends on macroscopic boundary conditions at the cosmol...
Gravitational Superenergy Tensor
Mashhoon, Bahram; McClune, James C.; Quevedo, Hernando
1996-01-01
We provide a physical basis for the local gravitational superenergy tensor. Furthermore, our gravitoelectromagnetic deduction of the Bel-Debever-Robinson superenergy tensor permits the identification of the gravitational stress-energy tensor. This {\\it local} gravitational analog of the Maxwell stress-energy tensor is illustrated for a plane gravitational wave.
Holonomy Attractor Connecting Spaces of Different Curvature Responsible for ``Anomalies''
Binder, Bernd
2009-03-01
In this lecture paper we derive Magic Angle Precession (MAP) from first geometric principles. MAP can arise in situations, where precession is multiply related to spin, linearly by time or distance (dynamic phase, rolling, Gauss law) and transcendentally by the holonomy loop path (geometric phase). With linear spin-precession coupling, gyroscopes can be spun up and down to very high frequencies via low frequency holonomy control induced by external accelerations, which provides for extreme coupling strengths or "anomalies" that can be tested by the powerball or gyrotwister device. Geometrically, a gyroscopic manifold with spherical metric is tangentially aligned to a precession wave channel with conic or hyperbolic metric (like the relativistic Thomas precession). Transporting triangular spin/precession vector relations across the tangential boundary of contact with SO(3) Lorentz symmetry, we get extreme vector currents near the attractor fixed points in precession phase space, where spin currents remain intact while crossing the contact boundaries between regions of different curvature signature (-1, 0, +1). The problem can be geometrically solved by considering a curvature invariant triangular condition, which holds on surfaces with different curvature that are in contact and locally parallel. In this case two out of three angles are identical, whereas the third angle is different due to holonomy. If we require that the side length ratio corresponding to these angles are invariant we get a geodesic chaotic attractor, which is a cosine map cos(x)˜Mx in parameter space providing for fixed points, limit cycle bifurcations, and singularities. The situation could be quite natural and common in the context of vector currents in curved spacetime and gauge theories. MAP could even be part of the electromagnetic interaction, where the electric charge is the geometric U(1) precession spin current and gauge potential with magnetic effects given by extra rotations under the SO(3). MAP can be extended to a neural network, where the synaptic connection of the holonomy attractor is just the mathematical condition adjusting and bridging spaces with positive (spherical) and negative (hyperbolic) curvature allowing for lossless/supra spin currents. Another strategy is to look for existing spin/precession anomalies and corresponding nonlinear holonomy conditions at the most fundamental level from the quark level to the cosmic scale. In these sceneries the geodesic attractor could control holonomy and curvature near the fixed points. It was proposed in 2002 that this should happen with electrons in atomic orbits showing a Berry phase part of the Rydberg or Sommerfeld fine structure constant and in 2003 that this effect could be responsible for (in)stabilities in the nuclear range and in superconductors. In 2008 it was shown that the attractor is part of the chaotic mechanical dynamics successfully at work in the Gyro-twister fitness device, and in 2007-2009 that there could be some deep relevance to "anomalies" in many scenarios even on the cosmic scales. Thus, we will point to and discuss some possible future applications that could be utilized for metric engineering: generating artificial holonomy and curvature (DC effect) for propulsion, or forcing holonomy waves (AC effect) in hyperbolic space-time, which are just gravitational waves interesting for communication.
Massive gravity as a quantum gauge theory
Grigore, D R; Grigore, Dan Radu; Scharf, Gunter
2004-01-01
We present a new point of view on the quantization of the massive gravitational field, namely we use exclusively the quantum framework of the second quantization. The Hilbert space of the many-gravitons system is a Fock space ${\\cal F}^{+}({\\sf H}_{\\rm graviton})$ where the one-particle Hilbert space ${\\sf H}_{graviton}$ carries the direct sum of two unitary irreducible representations of the Poincar\\'e group corresponding to two particles of mass $m > 0$ and spins 2 and 0, respectively. This Hilbert space is canonically isomorphic to a space of the type $Ker(Q)/Im(Q)$ where $Q$ is a gauge charge defined in an extension of the Hilbert space ${\\cal H}_{\\rm graviton}$ generated by the gravitational field $h_{\\mu\
International Nuclear Information System (INIS)
In this continuation of work by the author the notion of the distortion of an ideal crystal structure is generalized and the gauge field is defined, fundamental states (vacuum configurations) of which are the crystal structure elementary distortions due to dislocations. The form of the structure equations of the connection form defined by this gauge field is discussed
International Nuclear Information System (INIS)
A moisture and density gauge which combines sources of gamma and neutron radiation in a casing which is placed in the medium being analyzed. The gauge includes detectors for the gamma and neutron radiation being placed in end to end configuration within the casing such that the neutron detector is placed between the gamma radiation detector and the source of gamma radiation
Hamiltonian dynamics of gauge theories of gravity
International Nuclear Information System (INIS)
We investigate the Hamiltonian structure of gauge theories of gravity based on arbitrary gravitational and matter field Lagrangians. The gauge group of the theory in question is the semisimple product of the local Lorentz group and the group of diffeomorphisms of spacetime (the local Poincare group). We derive formulas for the symplectic two-form ?, the translational E, and the rotational J generators. The Hamilton equations expressed in terms of ?, E, and J are equivalent to the variational Euler-Lagrange equations. The ten constraint equations of the theory are closely related both to properties of the symplectic two-form ? and to an action of the gauge group in the space of solutions. The dynamical generators E and J can be expressed by the left-hand sides of the constraint equations, that is, the constraints generate the dynamics by means of the Hamilton equations for the functions E and J. On the other hand, the action of the gauge group in the set of initial data determines their ''time'' evolution. We show that this evolution is in a one-to-one correspondence with that generated by the Hamilton equations
Gravity, Gauge Theories and Geometric Algebra
Lasenby, A; Gull, S F; Lasenby, Anthony; Doran, Chris; Gull, Stephen
1998-01-01
A new gauge theory of gravity is presented. The theory is constructed in a flat background spacetime and employs gauge fields to ensure that all relations between physical quantities are independent of the positions and orientations of the matter fields. In this manner all properties of the background spacetime are removed from physics, and what remains are a set of `intrinsic' relations between physical fields. The properties of the gravitational gauge fields are derived from both classical and quantum viewpoints. Field equations are then derived from an action principle, and consistency with the minimal coupling procedure selects an action that is unique up to the possible inclusion of a cosmological constant. This in turn singles out a unique form of spin-torsion interaction. A new method for solving the field equations is outlined and applied to the case of a time-dependent, spherically-symmetric perfect fluid. A gauge is found which reduces the physics to a set of essentially Newtonian equations. These e...
Ngo Thanh, Hai
2011-01-01
In der vorliegenden Arbeit wird mit Hilfe der verallgemeinerten Eichtheorie/Gravitations-Dualität, welche stark gekoppelte Eichtheorien mit schwach gekrümmten gravitativen Theorien verbindet, stark korrelierte Quantenzustände der Materie untersucht. Der Schwerpunkt liegt dabei in Anwendungen auf Systeme der kondensierten Materie, insbesondere Hochtemperatur-Supraleitung und kritische Quantenzustände bei verschwindender Temperatur. Die Eichtheorie/Gravitations-Dualität entsta...
On the localization of the gravitational energy
Scientific Electronic Library Online (English)
N., Pinto Neto; P. I., Trajtenberg.
2000-03-01
Full Text Available Using a formalism introduced by Feynman, Deser, Grishchuk, Petrov and Popova, the pseudotensors, such as de.ned by Einstein, Tolman, Landau/Lifshitz and Møller, are expessed as gauge dependent tensors in a background space, as the gravitational energy-momentum tensor of Deser, Grishchuk, Petrov and [...] Popova. Using a result obtained by Virbhadra for the energy density in the Reissner-Nordström spacetime, it is shown that the action of these gauge transformations on the above tensorial expressions is the same as the action of the coordinate transformations on the equivalent pseudotensorial expressions, meaning that these tensors can be set to zero at a point by a suitable choice of gauge transformation.
Quaternion gauge fields. Pseudocolor
International Nuclear Information System (INIS)
A simplified Guenaydin-Guersey model, in which a Majorana field constructed using quaternions combines a lepton and a color quark, is considered. Formulation of the gauge principle directly in the quaternions leads to the appearance of two vector quaternion gauge fields, these corresponding to the decomposition SO(4) âˆ¼ SO(3) x SO(3) of the invariance group. The diagonal subgroup SO(3) of automorphisms of the quarternions appears as a pseudocolor symmetry of the quarks, and the gauge field corresponding to it as the field of three color gluons. The other gauge field corresponds to lepton-quark transitions and in the presence of spontaneous breaking of the SO(4) gauge symmetry by the scalar quaternion field acquires a (large) finite mass
Quaternion gauge field. Pseudocolor
International Nuclear Information System (INIS)
A simplified Guersay-Guenaydin model in which a lepton and a colour quark are united in the Majorana quaternion field is considered. Direct formulation of the gauge principle in the framework of quaternions leads to the appearance of two vector gauge quaternion fields corresponding to the decomposition of the invariance group SO(4)â‰…SO(3)xSO(3). The diagonal subgroup SO(3), the quaternion automorphism group, is considered as the quark pseudocolour symmetry and the corresponding gauge field is interpreted as the three-gluon-colour field. The other gauge field corresponds to lepton-quark transition and acquires a (large) finite mass under spontaneous breaking of SO(4) gauge symmetry due to the scalar quaternion field
Quantum Gravitational Decoherence of Light and Matter
Oniga, Teodora
2015-01-01
Real world quantum systems are open to perpetual influence from the wider environment. Vacuum gravitational fluctuations provide a most fundamental source of the environmental influence through their universal interactions with all forms of energy and matter causing decoherence. This may have subtle implications on precision laboratory experiments and astronomical observations and could limit the ultimate capacities for quantum technologies prone to decoherence. To establish the essential physical mechanism of decoherence under weak spacetime fluctuations, we carry out a sequence of analytical steps utilizing the Dirac constraint quantization and gauge invariant influence functional techniques, resulting in a general master equation of a compact form, that describes an open quantum gravitational system with arbitrary bosonic fields. An initial application of the theory is illustrated by the implied quantum gravitational dissipation of light as well as (non)relativistic massive or massless scalar particles. Re...
Bowler, Michael George
1976-01-01
Gravitation and Relativity generalizes Isaac Newton's theory of gravitation using the elementary tools of Albert Einstein's special relativity. Topics covered include gravitational waves, martian electrodynamics, relativistic gravitational fields and gravitational forces, the distortion of reference frames, and the precession of the perihelion of Mercury. Black holes and the geometry of spacetime also receive consideration. This book is comprised of 10 chapters; the first of which briefly reviews special relativity, with the emphasis on the Lorentz covariance of the equations of physics. This
Bel, Lluis
2009-01-01
A simple and {\\it innocent} modification of Poisson's equation leads to a modified Newtonnian theory of gravitation where a localized and {\\it positive} energy density of the gravitational field contributes to its own source. The result is that the total {\\it active gravitational mass} of a compact object is the sum of its {\\it proper mass} and an {\\it evanescent gravitational mass} which is a mass equivalent to the gravitational energy.
Anomaly induced effects in a magnetic field
Antoniadis, Ignatios; Ruchayskiy, O
2008-01-01
We consider a modification of electrodynamics by an additional light massive vector field, interacting with the photon via Chern-Simons-like coupling. This theory predicts observable effects for the experiments studying the propagation of light in an external magnetic field, very similar to those, predicted by theories of axion and axion-like particles. We discuss a possible microscopic origin of this theory from a theory with non-trivial gauge anomaly cancellation between massive and light particles (including, for example, millicharged fermions). Due to the conservation of the gauge current, the production of the new vector field is suppressed at high energies. As a result, this theory can avoid both stellar bounds (which exist for axions) and the bounds from CMB considered recently, allowing for positive results in experiments like ALPS, LIPPS, OSQAR, PVLAS-2, BMV, Q&A, etc.
Quantum gravitational effects in de Sitter space
Kiefer, C
1995-01-01
We calculate the first quantum gravitational correction term to the trace anomaly in De Sitter space from the Wheeler-DeWitt equation. This is obtained through an expansion of the full wave functional for gravity and a conformally coupled scalar field in powers of the Planck mass. We also discuss a quantum gravity induced violation of unitarity and comment on its possible relevance for inflation.
Interplay of gravitation and linear superposition of different mass eigenstates
Ahluwalia, D. V.; Burgard, C.
1998-01-01
The interplay of gravitation and the quantum-mechanical principle of linear superposition induces a new set of neutrino oscillation phases. These ensure that the flavor-oscillation clocks, inherent in the phenomenon of neutrino oscillations, redshift precisely as required by Einstein's theory of gravitation. The physical observability of these phases in the context of the solar neutrino anomaly, type-II supernovae, and certain atomic systems is briefly discussed.
Some Friedmann cosmological solutions in the scale covariant theory of gravitation
Directory of Open Access Journals (Sweden)
Aroonkumar Beesham
1991-06-01
Full Text Available The scale covariant theory of gravity admits the possibility of a time varying gravitational constant but contains a gauge function for which there is no independent equation. The circumstances under which explicit forms for a gauge function may be derived within the context of Friedmann-Robertson-Walker cosmological models are investigated and several forms are derived.
Choi, S Y; Song, H S
1993-01-01
Gravitational Compton scattering process with a massive fermion is studied in the context of the linearized gravity. Gravitational gauge invariance and graviton transversality cause the transition amplitude to be factorized into that of scalar QED Compton scattering and that of fermion QED Compton scattering with an overall kinematical factor. The factorization is shown explicitly and its physical implications are discussed.
The use of finite energy sum rules for the calculation of the induced gravitational constant
International Nuclear Information System (INIS)
We use the finite energy sum rules for the calculation of the induced gravitational constant in gauge theories of the QCD type. The induced gravitational constant is determined by the gluon vacuum condensate. Namely, (16?Gsub(ind))-1=(11/576?)2>sup(1/2). (orig.)
The heterotic ?-model with background gauge fields
International Nuclear Information System (INIS)
We develop methods for simplifying considerably the computation of ?-functions for the heterotic ?-model in the presence of background gauge fields. These methods are used to obtain three-loop results. Up to the overall normalization of the O(?'2) contribution, the ?-functions are on-shell equivalent to the equations of motion derived from an effective action which has been obtained previously in the string S-matrix approach. Our results shed, however, new light on the off-shell relation between these field equations and the ?-functions. It is also shown that, to all orders in ?', the net effect of gauge anomalies is the addition of a Chern-Simons term to the torsion. (orig.)
Field-theory interpretation of the gravitational interaction in electrodynamics
International Nuclear Information System (INIS)
The theory of gravitational interaction in classical electrodynamics on the base of suggested earlier minimal relativistic model of gravitation is developed. The system of gauge-invariant equations of coupled electromagnetic and gravitational fields is obtained and their common energy-momentum tensor is constructed by means of a variational principle. It is shown, that in the conditions of the existing resonant relation 2 : 3 of orbital and daily Mercury rotation the tidal forces cause the regular perihelion shift of this planet in observable direction forward on a movement course
Dynamical gauge coupling unification from moduli stabilization
Choi, K
2006-01-01
In D-brane models, different part of the 4-dimensional gauge group might originate from D-branes wrapping different cycles in the internal space, and then the standard model gauge couplings at the compactification scale are determined by different cycle-volume moduli. We point out that those cycle-volume moduli can naturally have universal vacuum expectation values up to small deviations suppressed by 1/8\\pi^2 if they are stabilized by KKLT-type non-perturbative superpotential. This dynamical unification of gauge couplings is independent of the detailed form of the moduli K\\"ahler potential, but relies crucially on the existence of low energy supersymmetry. If supersymmetry is broken by an uplifting brane as in KKLT compactification, again independently of the detailed form of the moduli K\\"ahler potential, the moduli-mediated gaugino masses at the compactification scale are universal also, and are comparable to the anomaly-mediated gaugino masses. As a result, both the gauge coupling unification at high ener...
Revisiting the gauge fields of strained graphene
Iorio, Alfredo; Pais, Pablo
2015-12-01
We show that when graphene is only subject to strain, the spin connection gauge field that arises plays no measurable role, but when intrinsic curvature is present and strain is small, spin connection dictates most of the physics. We do so by showing that the Weyl field associated with strain is a pure gauge field and no constraint on the (2 +1 )-dimensional spacetime appears. On the other hand, for constant intrinsic curvature that also gives a pure gauge Weyl field, we find a classical manifestation of a quantum Weyl anomaly, descending from a constrained spacetime. We are in the position to do this because we find the equations that the conformal factor in (2 +1 ) dimensions has to satisfy, which is a nontrivial generalization to (2 +1 ) dimensions of the classic Liouville equation of the differential geometry of surfaces. Finally, we comment on the peculiarities of the only gauge field that can describe strain, the well-known pseudogauge field A1˜u11-u22 and A2˜u12 , and conclude by offering some scenarios in fundamental physics that this peculiar field could help to realize.
Anomaly cancellation in K3 orientifolds
Scrucca, Claudio A; Scrucca, Claudio A.; Serone, Marco
2000-01-01
We study in detail the pattern of anomaly cancellation in D=6 Type IIB Z_N orientifolds, occurring through a generalized Green-Schwarz mechanism involving several RR antisymmetric tensors and scalars fields. The starting point is a direct string theory computation of the inflow of anomaly arising from magnetic interaction of D-branes, O-planes and fixed-points, which are encoded in topological one-loop partition functions in the RR odd spin-structure. All the RR anomalous couplings of these objects are then obtained by factorization. They are responsible for a spontaneous breaking of U(1) factors through a Higgs mechanism involving the corresponding hypermultiplets. Some of them are also related by supersymmetry to gauge couplings involving the NSNS scalars sitting in the tensor multiplets. We also comment on the possible occurrence of tensionless strings when these couplings diverge.
Anomaly cancellation for super-W-gravity
International Nuclear Information System (INIS)
We generalise the description of minimal superconformal models coupled to supergravity, due to Distler, Hlousek and Kawaii, to super-W-gravity. When the chiral algebra is the generalisation of the W-algebra associated to any contragredient Lie superalgebra the total central charge vanishes as a result of Lie superalgebra identities. When the algebra has only fermionic simple roots there is N=1 superconformal invariance and for this case we describe the Lax operators and construct gravitationally dressed primary superfields of weight zero. We also prove the anomaly cancellation associated with the generalised non-abelian Toda theories. (orig.)
Anomaly cancellation for super-W-gravity
Energy Technology Data Exchange (ETDEWEB)
Mansfield, P. (Dept. of Theoretical Physics, Univ. of Oxford (United Kingdom)); Spence, B. (Dept. of Physics, Univ. of Southampton (United Kingdom))
1991-08-08
We generalise the description of minimal superconformal models coupled to supergravity, due to Distler, Hlousek and Kawaii, to super-W-gravity. When the chiral algebra is the generalisation of the W-algebra associated to any contragredient Lie superalgebra the total central charge vanishes as a result of Lie superalgebra identities. When the algebra has only fermionic simple roots there is N=1 superconformal invariance and for this case we describe the Lax operators and construct gravitationally dressed primary superfields of weight zero. We also prove the anomaly cancellation associated with the generalised non-abelian Toda theories. (orig.).
Anomaly cancellation for super- W -gravity
Mansfield, P.; Spence, B.
1991-08-01
We generalise the description of minimal superconformal models coupled to supergravity, due to Distler, Hlousek and Kawaii, to super- W -gravity. When the chiral algebra is the generalisation of the W-algebra associated to any contragredient Lie superalgebra the total central charge vanishes as a result of Lie superalgebra identities. When the algebra has only fermionic simple roots there is N = 1 superconformal invariance and for this case we describe the Lax operators and construct gravitationally dressed primary superfields of weight zero. We also prove the anomaly cancellation associated with the generalised non-abelian Toda theories. Address from 1 October 1991: Physics Department, Imperial College, London SW7 2BZ, UK.
Gauge Theory by canonical Transformations
Koenigstein, Adrian; Stoecker, Horst; Struckmeier, Juergen; Vasak, David; Hanauske, Matthias
2016-01-01
Electromagnetism, the strong and the weak interaction are commonly formulated as gauge theories in a Lagrangian description. In this paper we present an alternative formal derivation of U(1)-gauge theory in a manifestly covariant Hamilton formalism. We make use of canonical transformations as our guiding tool to formalize the gauging procedure. The introduction of the gauge field, its transformation behaviour and a dynamical gauge field Lagrangian/Hamiltonian are unavoidable consequences of this formalism, whereas the form of the free gauge Lagrangian/Hamiltonian depends on the selection of the gauge dependence of the canonically conjugate gauge fields.
International Nuclear Information System (INIS)
Field studies to measure actual radiation exposures of operators of commercial moisture-density gauges were undertaken in several regions of Canada. Newly developed bubble detector dosimeter technology and conventional dosimetry such as thermoluminescent dosimeters (TLDs), integrating electronic dosimeters (DRDs), and CR-39 neutron track-etch detectors were used to estimate the doses received by 23 moisture-density gauge operators and maintenance staff. These radiation dose estimates were supported by mapping radiation fields and accounting for the time an operator was near a gauge. Major findings indicate that gauge maintenance and servicing workers were more likely than gauge operators to receive exposures above the level of 5 mSv, and that neutron doses were roughly the same as gamma doses. Gauge operators receive approximately 75% of their dose when transporting and carrying the gauge. Dose to their hands is similar to the dose to their trunks, but the dose to their feet area is 6 to 30 times higher. Gamma radiation is the primary source of radiation contributing to operator dose
Entanglement and Thermal Entropy of Gauge Fields
Eling, Christopher; Theisen, Stefan
2013-01-01
We consider the universal logarithmic divergent term in the entanglement entropy of gauge fields in the Minkowski vacuum with an entangling sphere. Employing the mapping in arXiv:1102.0440, we analyze the corresponding thermal entropy on open Einstein universe and on the static patch of de Sitter. Using the heat kernel of the vector Laplacian we resolve a discrepancy between the free field calculation and the expected Euler conformal anomaly. The resolution suggests a modification of the well known formulas for the vacuum expectation value of the spin-1 energy-momentum tensor on conformally flat space-times.
Post-Einsteinian tests of linearized gravitation
International Nuclear Information System (INIS)
The general relativistic treatment of gravitation can be extended by preserving the geometrical nature of the theory but modifying the form of the coupling between curvature and stress tensors. The gravitation constant is thus replaced by two running coupling constants which depend on scale and differ in the sectors of traceless and traced tensors. When calculated in the solar system in a linearized approximation, the metric is described by two gravitation potentials. This extends the parametrized post-Newtonian (PPN) phenomenological framework while allowing one to preserve compatibility with gravity tests performed in the solar system. Consequences of this extension are drawn here for phenomena correctly treated in the linear approximation. We obtain a Pioneer-like anomaly for probes with an eccentric motion as well as a range dependence of Eddington parameter ? to be seen in light deflection experiments
Gravitational energy from a combination of a tetrad expression and Einstein's pseudotensor
So, Lau Loi
2008-01-01
The energy-momentum for a gravitating system can be considered by the tetard teleparalle gauge current in orthonormal frames. Whereas the Einstein pseudotensor used holonomic frames. Tetrad expression itself gives a better result for gravitational energy than Einstein's. Inspired by an idea of Deser, we found a gravitational energy expression which enjoys the positive energy property by combining the tetrad expression and the Einstein pseudotensor, i.e., the connection coeff...
International Nuclear Information System (INIS)
We give a general definition of gauge mediated supersymmetry breaking which encompasses all the known gauge mediation models. In particular, it includes both models with messengers as well as direct mediation models. A formalism for computing the soft terms in the generic model is presented. Such a formalism is necessary in strongly-coupled direct mediation models where perturbation theory cannot be used. It allows us to identify features of the entire class of gauge mediation models and to distinguish them from specific signatures of various subclasses. (author)
Energy Technology Data Exchange (ETDEWEB)
Bacvinskas, W.S.; Bayer, J.E.; Davis, W.W.; Fodor, G.; Kikta, T.J.; Matchett, R.L.; Nilsen, R.J.; Wilczynski, R.
1991-12-31
The present invention is directed to a semi-automatic rod examination gauge for performing a large number of exacting measurements on radioactive fuel rods. The rod examination gauge performs various measurements underwater with remote controlled machinery of high reliability. The rod examination gauge includes instruments and a closed circuit television camera for measuring fuel rod length, free hanging bow measurement, diameter measurement, oxide thickness measurement, cladding defect examination, rod ovality measurement, wear mark depth and volume measurement, as well as visual examination. A control system is provided including a programmable logic controller and a computer for providing a programmed sequence of operations for the rod examination and collection of data.
Gravitational and Anti-gravitational Applications
Ellman, Roger
1998-01-01
It is now possible to partially deflect gravitation away from an object so that the gravitational attraction on the object is reduced. That effect makes it possible to extract energy from the gravitational field, which makes the generation of gravito-electric power technologically feasible. Such plants would be similar to hydro-electric plants and would have their advantages of not needing fuel and not polluting the environment. Physically, the action of deflecting away gr...
Dynamically Broken U(1) `Left' Gauge Theories in Four Dimensions
Machet, B
1993-01-01
We study a dynamically broken U(1) "left" gauge theory endowed with a composite scalar doublet (one scalar and one pseudoscalar); its Lagrangian only differs from that of an abelian `Standard Model' by the addition of a derivative coupling between a Wess-Zumino field, linked to the previous scalars, and the fermionic current. Yet, in the Feynman path integral, the non independence of the fermionic and scalar variables of integration requires the introduction of constraints. When the gauge symmetry is broken by the vacuum expectation value of the scalar field, they freeze all degrees of freedom but those of a massive gauge field, including a (abelian) pion. The anomaly disappears and the gauge current is conserved. This is shown, and renormalizability studied, in the `Nambu-Jona-Lasinio approximation'. Unitarity is demonstrated on general grounds.
Gauge Coupling Unification in Gauge-Higgs Grand Unification
Yamatsu, Naoki
2015-01-01
We discuss renormalization group equations for gauge coupling constants in gauge-Higgs grand unification on five-dimensional Randall-Sundrum warped space. We show that all the four-dimensional Standard Model gauge coupling constants are asymptotically free and are effectively unified in $SO(11)$ gauge-Higgs grand unified theories on 5D Randall-Sundrum warped space.
Effective Action for Hard Thermal Loops in Gravitational Fields
Francisco, R R; Taylor, J C
2016-01-01
We examine, through a Boltzmann equation approach, the generating action of hard thermal loops in the background of gravitational fields. Using the gauge and Weyl invariance of the theory at high temperature, we derive an explicit closed-form expression for the effective action.
Soliton solutions in relativistic field theories and gravitation
Diaz-Alonso, Joaquin; Rubiera-Garcia, Diego
2007-01-01
We report on some recent results on a class of relativistic lagrangian field theories supporting non-topological soliton solutions and their applications in the contexts of Gravitation and Cosmology. We analyze one and many-components scalar fields and gauge fields.
Torsion and curvature in terms of the axial gravitational superfield
International Nuclear Information System (INIS)
The usage of a geometric approach in the axial gravitational superfield is considered. The components of the torsion and curvature tensors is supergravity are explicitly expressed in terms of the derivatives of the axial superfield. The derivation is considerably simplified by the use of normal gauge in supergravity. The obtained results agree with the Grimm, Wess and Zumino data
Energy Technology Data Exchange (ETDEWEB)
Arkani-Hamed, Nima; Cohen, Andrew G.; Georgi, Howard
2001-03-16
We discuss the form of the chiral anomaly on an S1/Z2 orbifold with chiral boundary conditions. We find that the 4-divergence of the higher-dimensional current evaluated at a given point in the extra dimension is proportional to the probability of finding the chiral zero mode there. Nevertheless the anomaly, appropriately defined as the five dimensional divergence of the current, lives entirely on the orbifold fixed planes and is independent of the shape of the zero mode. Therefore long distance four dimensional anomaly cancellation ensures the consistency of the higher dimensional orbifold theory.
International Nuclear Information System (INIS)
The construction of field strength copies without any gauge constraint is discussed. Several examples are given, one of which is not only a field strength copy but also (at the same time) a 'current copy'. (author)
International Nuclear Information System (INIS)
Here some insight is provided into mathematical methods to analyze quantized gauge theories. This approach is being used to establish existence as well as to prove properties of gauge field models. Up to now, only abelian gauge fields are known to exist, namely the U(1) Higgs model on IR2 and IR3 and electrodynamics on the tori T2 and T3. In these lectures infrared properties of some of these models as studied. The non-Abelian gauge models are interesting for additional reasons: First, they have a natural geometric interpretation. Furthermore, because of asymptotic freedom, non-Abelian models have better local regularity properties than Abelian theories. Furthermore, they provide a rich analytic structure. In these notes ultraviolet properties of the d = 3 Yang-Mills theory are described. The Euclidean point of view is used throughout. The connection to real time follows from established results. 17 references, 8 figures
Maas, Axel
2012-01-01
QCD can be formulated using any gauge group. One particular interesting choice is to replace SU(3) by the exceptional group G2. Conceptually, this group is the simplest group with a trivial center. It thus permits to study the conjectured relevance of center degrees of freedom for QCD. Practically, since all its representation are real, it is possible to perform lattice simulations for this theory also at finite baryon densities. It is thus an excellent environment to test methods and to investigate general properties of gauge theories at finite densities. We review the status of our understanding of gauge theories with the gauge group G2, including Yang-Mills theory, Yang-Mills-Higgs theory, and QCD both in the vacuum and in the phase diagram.
National Aeronautics and Space Administration — Cog-Gauge is a portable hand-held game that can be used by astronauts and crew members during space exploration missions to assess their cognitive workload...
Taking Kaluza seriously leads to a non-gauge-invariant electromagnetic theory in a curved space-time
Fabbri, Luca
2002-01-01
Kaluza's mertic with the cylinder condition is considered without the weak gravitational field approximation. It is shown that these hypoteses lead to a non-gauge-invariant electromagnetic theory in a curved space-time. The problem of electro-gravitational unification is considered from this point of view.
Anomalous gauge theories revisited
Matsui, Kosuke; Suzuki, Hiroshi(Department of Physics, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka, 812-8581, Japan)
2004-01-01
A possible formulation of chiral gauge theories with an anomalous fermion content is re-examined in light of the lattice framework based on the Ginsparg-Wilson relation. It is shown that the fermion sector of a wide class of anomalous non-abelian theories cannot consistently be formulated within this lattice framework. In particular, in 4 dimension, {\\it all} anomalous non-abelian theories are included in this class. Anomalous abelian chiral gauge theories cannot be formulat...
Gauging without initial symmetry
Kotov, Alexei; Strobl, Thomas
2016-01-01
The gauge principle is at the heart of a good part of fundamental physics: Starting with a group G of so-called rigid symmetries of a functional defined over space-time ?, the original functional is extended appropriately by additional Lie(G) -valued 1-form gauge fields so as to lift the symmetry to Maps(? , G) . Physically relevant quantities are then to be obtained as the quotient of the solutions to the Euler-Lagrange equations by these gauge symmetries. In this article we show that one can construct a gauge theory for a standard sigma model in arbitrary space-time dimensions where the target metric is not invariant with respect to any rigid symmetry group, but satisfies a much weaker condition: It is sufficient to find a collection of vector fields va on the target M satisfying the extended Killing equationv a(i ; j) = 0 for some connection acting on the index a. For regular foliations this is equivalent to requiring the conormal bundle to the leaves with its induced metric to be invariant under leaf-preserving diffeomorphisms of M, which in turn generalizes Riemannian submersions to which the notion reduces for smooth leaf spaces M / ?. The resulting gauge theory has the usual quotient effect with respect to the original ungauged theory: in this way, much more general orbits can be factored out than usually considered. In some cases these are orbits that do not correspond to an initial symmetry, but still can be generated by a finite-dimensional Lie group G. Then the presented gauging procedure leads to an ordinary gauge theory with Lie algebra valued 1-form gauge fields, but showing an unconventional transformation law. In general, however, one finds that the notion of an ordinary structural Lie group is too restrictive and should be replaced by the much more general notion of a structural Lie groupoid.
Nuclear radiation gauge standard
International Nuclear Information System (INIS)
A calibration standard for thermal neutron moisture gauges is claimed. It comprises a hydrophobic body formed of a moderating material containing hydrogen in its molecular structure and a substantially non-moderating material. The materials are arranged so that there is a uniform distribution of moderating material throughout the body in order to impart physical characteristics which are effective for representing a mass of homogenous hydrogen content to a nuclear gauge undergoing calibration
Induced gauge interactions revisited
Broda, Bogus?aw; Szanecki, Micha?
2010-01-01
It has been shown that the old-fashioned idea of Sakharov's induced gravity and gauge interactions in the "one-loop dominance" version works astonishingly well yielding reasonable parameters. It appears that induced coupling constants of gauge interactions of the standard model assume qualitatively realistic values. Moreover, it is possible to induce the Barbero--Immirzi parameter of canonical gravity from the fields entering the standard model.
Running Couplings in Quantum Theory of Gravity Coupled with Gauge Fields
Narain, Gaurav
2013-01-01
In this paper we study the coupled system of non-abelian gauge fields with higher-derivative gravity. Charge renormalization is investigated in this coupled system. It is found that the leading term in the gauge coupling beta function comes due to interaction of gauge fields with gravitons. This is shown to be a universal quantity in the sense that it doesn't depend on the gauge coupling and the gauge group, but may depend on the other couplings of the action (gravitational and matter). The coupled system is studied at one-loop. It is found that the leading term of gauge beta function is zero at one-loop in four dimensions. The effect of gauge fields on the running of gravitational couplings is investigated. The coupled system of gauge field with higher-derivative gravity is shown to satisfy unitarity when quantum corrections are taken in to account. Moreover, it is found that Newton constant goes to zero at short distances. In this renormalizable and unitary theory of gauge field coupled with higher-derivati...
International Nuclear Information System (INIS)
We present a unified framework to describe lattice gauge theories by means of tensor networks: this framework is efficient as it exploits the high local symmetry content native to these systems by describing only the gauge invariant subspace. Compared to a standard tensor network description, the gauge invariant model allows one to increase real and imaginary time evolution up to a factor that is square of the dimension of the link variable. The gauge invariant tensor network description is based on the quantum link formulation, a compact and intuitive formulation for gauge theories on the lattice, which is alternative to and can be combined with the global symmetric tensor network description. We present some paradigmatic examples that show how this architecture might be used to describe the physics of condensed matter and high-energy physics systems. Finally, we present a cellular automata analysis which estimates the gauge invariant Hilbert space dimension as a function of the number of lattice sites that might guide the search for effective simplified models of complex theories. (paper)
International Nuclear Information System (INIS)
The author summarizes the works presented at the meeting on skyrmions and anomalies. He divides the principal issues of this workshop into five categories: QCD effective lagrangians, chiral bags and the Cheshire cat principle, strangeness problem, phenomenology, mathematical structure
Neutrino anomalies without oscillations
Indian Academy of Sciences (India)
Sandip Pakvasa
2000-01-01
I review explanations for the three neutrino anomalies (solar, atmospheric and LSND) which go beyond the `conventional' neutrino oscillations induced by mass-mixing. Several of these require non-zero neutrino masses as well.
Anomaly Detection in Sequences
National Aeronautics and Space Administration â€” We present a set of novel algorithms which we call sequenceMiner, that detect and characterize anomalies in large sets of high-dimensional symbol sequences that...
Anomalies, entropy and boundaries
Fursaev, Dmitri V
2016-01-01
A relation between the conformal anomaly and the logarithmic term in the entanglement entropy is known to exist for CFT's in even dimensions. In odd dimensions the local anomaly and the logarithmic term in the entropy are absent. As was observed recently, there exists a non-trivial integrated anomaly if an odd-dimensional spacetime has boundaries. We show that, similarly, there exists a logarithmic term in the entanglement entropy when the entangling surface crosses the boundary of spacetime. The relation of the entanglement entropy to the integrated conformal anomaly is elaborated for three-dimensional theories. Distributional properties of intrinsic and extrinsic geometries of the boundary in the presence of conical singularities in the bulk are established. This allows one to find contributions to the entropy that depend on the relative angle between the boundary and the entangling surface.
Simplicial gauge theory on spacetime
Halvorsen, Tore Gunnar
2011-01-01
We define a discrete gauge-invariant Yang-Mills-Higgs action on spacetime simplicial meshes. The formulation is a generalization of classical lattice gauge theory, and we prove consistency of the action in the sense of approximation theory. In addition, we perform numerical tests of convergence towards exact continuum results for several choices of gauge fields in pure gauge theory.
Palguta, J.; Anderson, J. D.; Schubert, G.; Moore, W. B.
2004-12-01
The discovery of mass anomalies on Ganymede was reported this summer (Anderson et al., Science 305, 989 (2004)). We report here on a more detailed characterization of the source of the anomalies. In order to reduce the noise evident in the Doppler residuals previously used, we applied a variable-width Gaussian filter to the time series. The filter width in the time domain increases with the spacecraft altitude, reducing the noise before and after closest approach. The smoothed Doppler data were numerically differentiated and the resulting accelerations along the line of sight were fit with a multiple point-mass model. The variable-width filter reveals a previously obscured positive acceleration feature about 300 s before closest approach. Rather than two or three mass points as reported in Anderson et al., we find that five mass points provide a much improved fit to the data, including the new acceleration feature before closest approach. Two of the five masses are near the previous masses from the two-point fit, and are in good agreement with their mass values. There is a positive anomaly at about 60o north latitude and a negative anomaly at about 24o north latitude. We conclude that the two-point fit reveals two major anomalies on Ganymede, but misses three more revealed by the five-point fit. Further, the mass anomalies can be divided into two groups. Three of the five masses could indicate a single broad anomaly under the outgoing flyby trajectory centered roughly at 45o north latitude and 18o west longitude. The other two masses could indicate a single extended anomaly under the incoming trajectory centered roughly at 20o north latitude and 173o west longitude. We also include results on placing the five masses at different depths from zero to 1450 km below the surface. A good fit is obtained at any depth from surface to rock-ice interface at about 800 km depth, but the fit deteriorates at greater depth. It is highly unlikely mass anomalies exist within Ganymede's ice shell. We prefer either the near surface or the rock-ice interface. The rock-ice interface is attractive based on rigidity arguments, and the suggestion of two major extended anomalies is even more striking at greater depth. In order to fit the acceleration data, the anomalies must be six or seven times more massive at the 800 km depth than at the surface.
Underdevelopment’s gravitation
Directory of Open Access Journals (Sweden)
Marin Dinu
2013-09-01
Full Text Available The energy necessary to escape the gravitational pull of underdevelopment and to enter an evolutional trajectory dependent on the gravitational pull of development is unintelligible in economic terms.
On the gravitational scattering of gravitational waves
International Nuclear Information System (INIS)
We discuss the scattering of weak gravitational waves from a slowly rotating gravitational source, having mass M and angular momentum J-vector . We start considering the dynamics of a massless spin-2 field ??? propagating in the weak gravitational field of the source, writing down the Fierz–Pauli in the presence of a slightly curved background. We adopt a semiclassical framework, where the gravitational background is described as a classical external field; meanwhile, the spin-2 field is treated quantum mechanically. In the weak-coupling limit, in which the typical wavelength of ??? satisfies ???Rs (where Rs is the Schwarzschild radius of the source), we obtain the cross-section for the scattering process in the Born approximation. We also discuss helicity asymmetry, showing its relationship with the spin-2 field coupling to the derivatives of the background metric. We finally consider the transition to the case of gravitational wave scattering, showing that—under reasonable assumptions—gravitational waves are expected to follow the same behavior. Our results partly agree with those presented through the years by various authors. The present analysis suggests that the scattering of weak gravitational waves in the field of a macroscopic gravitational source still represents an interesting open issue for further careful investigation. (paper)
Boyda, E; Pierce, A T; Boyda, Ed; Murayama, Hitoshi; Pierce, Aaron
2002-01-01
We offer a guide to dimensional reduction (DRED) in theories with anomaly mediated supersymmetry breaking. Evanescent operators proportional to epsilon arise in the bare Lagrangian when it is reduced from d=4 to d= (4-2 epsilon) dimensions. In the course of a detailed diagrammatic calculation, we show that inclusion of these operators is crucial. The evanescent operators conspire to drive the supersymmetry-breaking parameters along anomaly-mediation trajectories across heavy particle thresholds, guaranteeing the ultraviolet insensitivity.
de Diego, Jose A
2008-01-01
Analysis of the radio-metric data from Pioneer 10 and 11 spacecrafts has indicated the presence of an unmodeled acceleration starting at 20 AU, which has become known as the Pioneer anomaly. The nature of this acceleration is uncertain. In this paper we give a description of the effect and review some relevant mechanisms proposed to explain the observed anomaly. We also discuss on some future projects to investigate this phenomenon.
Scale-covariant theory of gravitation and astrophysical applications
Canuto, V.; Adams, P. J.; Hsieh, S.-H.; Tsiang, E.
1977-01-01
A scale-covariant theory of gravitation is presented which is characterized by a set of equations that are complete only after a choice of the scale function is made. Special attention is given to gauge conditions and units which allow gravitational phenomena to be described in atomic units. The generalized gravitational-field equations are derived by performing a direct scale transformation, by extending Riemannian geometry to Weyl geometry through the introduction of the notion of cotensors, and from a variation principle. Modified conservation laws are provided, a set of dynamical equations is obtained, and astrophysical consequences are considered. The theory is applied to examine certain homogeneous cosmological solutions, perihelion shifts, light deflections, secular variations of planetary orbital elements, stellar structure equations for a star in quasi-static equilibrium, and the past thermal history of earth. The possible relation of the scale-covariant theory to gauge field theories and their predictions of cosmological constants is discussed.
Vacuum stability bounds on higgs mass with gravitational contributions
International Nuclear Information System (INIS)
We calculate the gravitational contributions to ?4 theory with general R? gauge-fixing choice and find that the result is gauge independent. Based on weak coupling expansion of gravity and ignoring the possible higher dimensional operators from “integrating out” the impact of gravity, we study the impacts of gravitational effects on vacuum stability. New contributions to the beta function of scalar quartic coupling ? by gravitational effects can modify the RGE running of ? near the Planck scale. Numerical calculations show that the lower bound of higgs mass requiring absolutely vacuum stability can be relaxed for almost 0.6 to 0.8 GeV depending on the choice of top quark mass
Scalar potential and dyonic strings in 6D gauged supergravity
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In this paper we first give a simple parametrization of the scalar coset manifold of the only known anomaly free chiral gauged supergravity in six dimensions in the absence of linear multiplets, namely gauged minimal supergravity coupled to a tensor multiplet, E6 x E7 X U(1)R Yang-Mills multiplets and suitable number of hypermultiplets. We then construct the potential for the scalars and show that it has a unique minimum at the origin. We also construct a new BPS dyonic string solution in which U(1)R x U(1) gauge fields, in addition to the metric, dilaton and the 2-form potential, assume nontrivial configurations in any U(1)R gauged 6D minimal supergravity coupled to a tensor multiplet with gauge symmetry G contains U(1). The solution Preserves 1/4 of the 6D supersymmetries and can be trivially embedded in the anomaly free model, in which case the U(1) activated in our solution resides in E7. (author)
Moortgat, Joachim
2001-01-01
In the vicinity of merging neutron strar binaries or supernova remnants, gravitational waves can interact with the prevailing strong magnetic fields. The resulting partial conversion of gravitational waves into electromagnetic (radio) waves might prove to be an indirect way of detecting gravitational waves from such sources. Another interesting interaction considered in this article is the excitation of magnetosonic plasma waves by a gravitational wave passing through the surrounding plasma. ...
Aufmuth, P.; Danzmann, K.
2005-01-01
The existence of gravitational radiation is a prediction of Einstein's general theory of relativity. Gravitational waves are perturbations in the curvature of spacetime caused by accelerated masses. Since the 1960s gravitational wave detectors have been built and constantly improved. The present-day generation of resonant mass antennas and laser interferometers has reached the necessary sensitivity to detect gravitational waves from sources in the Milky Way. Within a few years, the next gener...
International Nuclear Information System (INIS)
The first six chapters of this book: physical fundamentals, Riemann's geometry, gravitational theory, experimental tests of the general theory of relativity, cosmology and gravitational waves, give a survey on the 'classical' results of the relativity theory. In the chapters to follow, aspects of more recent development are dealt with: new differential geometrical methods, star formation and gravitational collapse, fields in the Riemann's space, gravitation and field theory. (BJ/LH)
Green-Schwarz anomaly cancellation, world sheet instantons and wormholes
International Nuclear Information System (INIS)
We consider the breaking of the global conservation of gauge field charges which are commonly thought to survive the spontaneous breakdown of gauge symmetry brought about by Kalb-Ramond fields. Depending on the dilaton field and also the size of the compactifying space, the global charge breaking may take place due to world sheet instantons. In going to 3+1 dimensions one could have a serious problem in order to produce the hierarchies between the quark and the charged lepton masses using the mass protecting charges with the Green-Schwartz anomaly cancellation. Various unnatural features of this type of models are discussed. (author)
Detection of gravitational radiation
Energy Technology Data Exchange (ETDEWEB)
Holten, J.W. van [ed.
1994-12-31
In this report the main contributions presented at the named symposium are collected. These concern astrophysical sources of gravitational radiation, ultracryogenic gravitational wave experiments, read out and data analysis of gravitational wave antennas, cryogenic aspects of large mass cooling to mK temperatures, and metallurgical and engineering aspects of large Cu structure manufacturing. (HSI).
Detection of gravitational radiation
International Nuclear Information System (INIS)
In this report the main contributions presented at the named symposium are collected. These concern astrophysical sources of gravitational radiation, ultracryogenic gravitational wave experiments, read out and data analysis of gravitational wave antennas, cryogenic aspects of large mass cooling to mK temperatures, and metallurgical and engineering aspects of large Cu structure manufacturing. (HSI)
Ridgely, Charles T.
2011-01-01
When two gravitating bodies reside in a material medium, Newton's law of universal gravitation must be modified to account for the presence of the medium. A modified expression of Newton's law is known in the literature, but lacks a clear connection with existing gravitational theory. Newton's law in the presence of a homogeneous material medium…
Connecting anomaly and tunneling methods for the Hawking effect through chirality
International Nuclear Information System (INIS)
The role of chirality is discussed in unifying the anomaly and the tunneling formalisms for deriving the Hawking effect. Using the chirality condition and starting from the familiar form of the trace anomaly, the chiral (gravitational) anomaly, manifested as a nonconservation of the stress tensor, near the horizon of a black hole, is derived. Solution of this equation yields the stress tensor whose asymptotic infinity limit gives the Hawking flux. Finally, use of the same chirality condition in the tunneling formalism gives the Hawking temperature that is compatible with the flux obtained by anomaly method.
A little more gauge mediation and the light Higgs mass
Energy Technology Data Exchange (ETDEWEB)
Suryanarayana Mummidi, V., E-mail: soori9@cts.iisc.ernet.in; Vempati, Sudhir K., E-mail: vempati@cts.iisc.ernet.in
2014-04-15
We consider minimal models of gauge mediated supersymmetry breaking with an extra U(1) factor in addition to the Standard Model gauge group. A U(1) charged, Standard Model singlet is assumed to be present which allows for an additional NMSSM like coupling, ?H{sub u}H{sub d}S. The U(1) is assumed to be flavour universal. Anomaly cancellation in the MSSM sector requires additional coloured degrees of freedom. The S field can get a large vacuum expectation value along with consistent electroweak symmetry breaking. It is shown that the lightest CP even Higgs boson can attain mass of the order of 125 GeV.
A little more gauge mediation and the light Higgs mass
Suryanarayana Mummidi, V.Centre for High Energy Physics, Indian Institute of Science, Bangalore 560012, India; Sudhir K. Vempati
2014-01-01
We consider minimal models of gauge mediated supersymmetry breaking with an extra U(1) factor in addition to the Standard Model gauge group. A U(1) charged, Standard Model singlet is assumed to be present which allows for an additional NMSSM like coupling, ?HuHdS . The U(1) is assumed to be flavour universal. Anomaly cancellation in the MSSM sector requires additional coloured degrees of freedom. The S field can get a large vacuum expectation value along with consistent electroweak symmetry b...
A little more Gauge Mediation and the light Higgs mass
Mummidi, V Suryanarayana
2013-01-01
We consider minimal models of gauge mediated supersymmetry breaking with an extra $U(1)$ factor in addition to the Standard Model gauge group. A $U(1)$ charged, Standard Model singlet is assumed to be present which allows for an additional NMSSM like coupling, $\\lambda H_u H_d S$. The U(1) is assumed to be flavour universal. Anomaly cancellation in the MSSM sector requires additional coloured degrees of freedom. The $S$ field can get a large vacuum expectation value along with consistent electroweak symmetry breaking. It is shown that the lightest CP even Higgs boson can attain mass of the order of 125 GeV.
Neutrinos and abelian gauge symmetries
International Nuclear Information System (INIS)
We study the intimate connection between neutrinos and simple abelian gauge symmetries U(1)', starting from the observation that the full global symmetry group of the Standard Model, G=U(1)B-L x U(1)Le-LÎ¼ x U(1)LÎ¼-LÏ„, can be promoted to a local symmetry group by introducing three right-handed neutrinos - automatically making neutrinos massive. The unflavored part U(1)B-L is linked to the Dirac vs. Majorana nature of neutrinos; we discuss the B-L landscape - including lepton-number-violating Dirac neutrinos - and implications for neutrinos, the baryon asymmetry, and experiments. Flavored subgroups U(1)' is contained in G can shed light on the peculiar leptonic mixing pattern and mass ordering; we show how normal, inverted, and quasi-degenerate mass hierarchy can arise from a U(1)' in a simple and testable manner. We furthermore present all U(1)' is contained in G that can enforce viable texture zeros in the neutrino mass matrices. Beyond G, symmetries U(1)DM in the dark matter sector can give rise to naturally light sterile neutrinos, which provide a new portal between visible and dark sector, and also resolve some longstanding anomalies in neutrino experiments. Further topics under consideration are the mixing of vector bosons with the Z boson, as well as the Stueckelberg mechanism. The latter raises the question why the photon should be massless - or stable for that matter.
Gauge theories of gravity and supergravity
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Differential geometry and its applications to general relativity and linear gauge theories are first reviewed. A fiber bundle formation for gravity is developed using space-time as the base space and the de-Sitter group as the fiber. The de-Sitter group is broken to the Lorentz group, and the translation generators are interlocked with the covariant derivatives. This leads to nonlinear gauge transformations which are equivalent to general coordinate transformations on space-time. It is found that Einstein's Lagrangian is invariant under these transformations up to a total divergence. Conformal gravity and gravity directly coupled to a Yang-Mills theory are then examined. This formalism is extended to supergravity by extending space-time to a 4 + 4N dimensional superspace and using the orthosymplectic groups OSp(4:N) for the fiber. The geometry of superspace is first discussed. Nonlinear gauge transformations are then derived making use of an interlocking condition, and Lagrangians invariant under these transformation laws up to a total divergence are constructed. Transformation laws for conformal supergravity are also derived. Finally, an alternative to superspace in which the line element of general relativity is maintained is developed. It is argued that the metric on such a space contains just enough fields to possibly be able to include the gravitational, weak, and electromagnetic interactions
Gauge fields in a torsion field
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In this paper we analyse the motion and the field equations in a non-null curvature and torsion space. In this 4-n dimensional space, the connection coefficients are ?bca = 1/2Sbca + 1/2Tbca, where Sbca is the symmetrical part and Tbca are the components of the torsion tensor. We will consider that all the fields depend on x = x?, ? = 1,2,3,4 and do not depend on y = yk, k=1,2,...,n. The factor Sbca depends on the components of the metric tensor g??(x) and on the gauge fields A?s0(x) and the components of the torsion depend only on the gauge fields A?s0(x). We take into consideration the particular case for which the geodesic equations coincide with the motion equations in the presence of the gravitational and the gauge fields. In this case the field equations are Einstein equations in a 4-n dimensional space. We show that both the geodesic equations and the field equations can be obtained from a variational principle. (author)
A gravitational effective action on a finite triangulation
International Nuclear Information System (INIS)
We construct a function of the edge-lengths of a triangulated surface whose variation under a rescaling of all the edges that meet at a vertex is the defect angle at that vertex. We interpret this function as a gravitational effective action on the triangulation, and the variation as a trace anomaly
Holographic anomaly in 3d f(Ric) gravity
Loran, Farhang
2013-01-01
By applying the holographic renormalization method to the metric formalism of f(Ric) gravity in three dimensions, we obtain the Brown-York boundary stress-tensor for backgrounds which asymptote to the locally AdS3 solution of Einstein gravity. The logarithmic divergence of the on-shell action can be subtracted by a non-covariant cut-off independent term which exchanges the trace anomaly for a gravitational anomaly. We show that the central charge can be determined by means of BTZ holography or in terms of the Hawking effect of a Schwarzschild black hole placed on the boundary.
Ogilvie, Michael C
2012-01-01
One of the most fundamental questions we can ask about a given gauge theory is its phase diagram. In the standard model, we observe three fundamentally different types of behavior: QCD is in a confined phase at zero temperature, while the electroweak sector of the standard model combines Coulomb and Higgs phases. Our current understanding of the phase structure of gauge theories owes much to the modern theory of phase transitions and critical phenomena, but has developed into a subject of extensive study. After reviewing some fundamental concepts of phase transitions and finite-temperature gauge theories, we discuss some recent work that broadly extends our knowledge of the mechanisms that determine the phase structure of gauge theories. A new class of models with a rich phase structure has been discovered, generalizing our understanding of the confinement-deconfinement transition in finite-temperature gauge theories. Models in this class have space-time topologies with one or more compact directions. On R^3 ...
Poincare gauge in electrodynamics
International Nuclear Information System (INIS)
The gauge presented here, which we call the Poincare gauge, is a generalization of the well-known expressions phi = -rxE0 and A = 1/2 B0 x r for the scalar and vector potentials which describe static, uniform electric and magnetic fields. This gauge provides a direct method for calculating a vector potential for any given static or dynamic magnetic field. After we establish the validity and generality of this gauge, we use it to produce a simple and unambiguous method of computing the flux linking an arbitrary knotted and twisted closed circuit. The magnetic flux linking the curve bounding a Moebius band is computed as a simple example. Arguments are then presented that physics students should have the opportunity of learning early in their curriculum modern geometric approaches to physics. (The language of exterior calculus may be as important to future physics as vector calculus was to the past.) Finally, an appendix illustrates how the Poincare gauge (and others) may be derived from Poincare's lemma relating exact and closed exterior differential forms
Physical anomaly on the lattice
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The authors study the axial anomaly of chiral non-invariant generalized Wilson's action and point out a possibility that physical anomaly which is responsible for ?0 ? 2? decay and ?-eta-eta' mass difference vanishes. The physical anomaly is different from the commonly defined anomaly which has correct magnitude. (Auth.)
Causality versus gauge invariance in quantum gravity and supergravity
International Nuclear Information System (INIS)
It is proposed that one should admit in the path integral for the quantized gravitational field only those space-times for which the final three-geometry is located in the future of the initial one. As a consequence, and unlike the situation for the Yang-Mills field, the resulting causal amplitude is not annihilated by all the gauge (surface deformation) generators. In supergravity the causal amplitude turns out not to be annihilated by the local supersymmetry generators either
S-Dual Gravity in the Axial Gauge
Ellwanger, U
2006-01-01
We investigate an action that includes simultaneously original and dual gravitational fields (in the first order formalism), where the dual fields are completely determined in terms of the original fields through axial gauge conditions and partial (non-covariant) duality constraints. We introduce two kinds of matter, one that couples to the original metric, and dual matter that couples to the dual metric. The linear response of both metrics to the corresponding stress energy...
Flavour dependent gauged radiative neutrino mass model
Baek, Seungwon; Okada, Hiroshi; Yagyu, Kei
2015-04-01
We propose a one-loop induced radiative neutrino mass model with anomaly free flavour dependent gauge symmetry: ? minus ? symmetry U(1) ?- ? . A neutrino mass matrix satisfying current experimental data can be obtained by introducing a weak isospin singlet scalar boson that breaks U(1) ?- ? symmetry, an inert doublet scalar field, and three right-handed neutrinos in addition to the fields in the standard model. We find that a characteristic structure appears in the neutrino mass matrix: two-zero texture form which predicts three non-zero neutrino masses and three non-zero CP-phases from five well measured experimental inputs of two squared mass differences and three mixing angles. Furthermore, it is clarified that only the inverted mass hierarchy is allowed in our model. In a favored parameter set from the neutrino sector, the discrepancy in the muon anomalous magnetic moment between the experimental data and the the standard model prediction can be explained by the additional neutral gauge boson loop contribution with mass of order 100 MeV and new gauge coupling of order 10-3.
On gauged Baryon and Lepton numbers
International Nuclear Information System (INIS)
The observation that Baryon number and Lepton number are conserved in nature provides strong motivation for associating gauge symmetries to these conserved numbers. This endeavor requires that the gauge group of electroweak interactions be extended from SU(2)L X U(1)Y to SU(2)L X U(1)R X U(1)Lepton where U(1)R couples only to the right-handed quarks and leptons. If it furthur postulated that right-handed currents exist on par with the left-handed ones, then the full electroweak symmetry is SU(2)L X SU(2)R X U(1)Baryon X U(1)Lepton. The SU(2)L X SU(2)R X U(1)Baryon X U(1)Lepton model is described in some detail. The triangle anomalies of the three families of quarks and leptons in the model are cancelled invoking leptoquark matter which is new fermionic matter that carries baryon as well as lepton numbers. In addition to the standard neutral boson (Z degree), the theory predicts two neutral gauge bosons with mass lower bounds of 120 GeV and 210 GeV which makes these particles prospective candidates for production at LEP, the TEVATRON and the SSC
DEFF Research Database (Denmark)
Mojaza, Matin; Pica, Claudio; Sannino, Francesco
2010-01-01
We compute the nonzero temperature free energy up to the order g^6 \\ln(1/g) in the coupling constant for vector like SU(N) gauge theories featuring matter transforming according to different representations of the underlying gauge group. The number of matter fields, i.e. flavors, is arranged in...... such a way that the theory develops a perturbative stable infrared fixed point at zero temperature. Due to large distance conformality we trade the coupling constant with its fixed point value and define a reduced free energy which depends only on the number of flavors, colors and matter representation...... flavors. Surprisingly this number, if computed to the order g^2, agrees with previous predictions for the lower boundary of the conformal window for nonsupersymmetric gauge theories. The higher order results tend to predict a higher number of critical flavors. These are universal properties, i.e. they are...
Aganagic, Mina; Kozcaz, Can; Shakirov, Shamil
2013-01-01
Conformal blocks of Liouville theory have a Coulomb-gas representation as Dotsenko-Fateev (DF) integrals over the positions of screening charges. For q-deformed Liouville, the conformal blocks on a sphere with an arbitrary number of punctures are manifestly the same, when written in DF representation, as the partition functions of a class of 3d U(N) gauge theories with N=4 supersymmetry, mass deformed to N=2, in the Omega-background. Coupling the 3d gauge theory to a hypermultiplet in fundamental representation corresponds to inserting a Liouville vertex operator; the two real mass parameters determine the momentum and position of the puncture. The DF integrals can be computed by residues. The result is the instanton sum of a five dimensional N=1 gauge theory. The positions of the poles are labeled by tuples of partitions, the residues of the integrand are the Nekrasov summands.
Discrete Abelian gauge symmetries
International Nuclear Information System (INIS)
We investigate the possibility to gauge discrete Abelian symmetries. An algebraic approach to understanding general Abelian discrete groups, which govern the coupling structure of a physical theory is presented. In particular, the embedding of a general Abelian discrete group Zd1 x.. x Zdr into a general Abelian gauge group U(1)k via spontaneous symmetry breaking of the continuous group is elaborated in detail. A promising candidate for the embedding of any discrete gauge symmetry is string theory. The algebraic approach to general discrete Abelian groups establishes new possibilities of controlling the coupling structure in string derived model building. We discuss phenomenological consequences of discrete Abelian symmetries arising in string derived MSSM models. A simple discrete R-symmetry, ZR4, which contains matter parity as non-anomalous subgroup, is capable of resolving multiple issues such as dimension four and five proton decay as well as the ?-problem.
${\\cal N} = 1$ Euler Anomaly Flow from Dilaton Effective Action
Prochazka, Vladimir
2015-01-01
We consider ${\\cal N} =1$ supersymmetric gauge theories in the conformal window. The running of the gauge coupling is absorbed into the metric by applying a suitable matter superfield- and Weyl-transformation. The computation becomes equivalent to one of a free theory in a curved background carrying the information of the renormalisation group flow. We use the techniques of conformal anomaly matching and dilaton effective action, by Komargodski and Schwimmer, to rederive the difference of the Euler anomaly coefficient $\\Delta a \\equiv a_{\\rm UV} - a_{\\rm IR} $ for the ${\\cal N} =1$ theory. The structure of $\\Delta a $ is therefore in one-to-one correspondence with the Wess-Zumino dilaton action.
Renormalization with flow equations and the ABJ anomaly
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We study the renormalizability of axial abelian gauge theory within the flow equation framework in which the theory is regularized in a way which does not respect gauge-invariance but permits to rigorously apply Euclidean path integral methods. On the one hand we prove renormalizability in the weak sense of power counting; on the other hand we analyse the Slavnov-Taylor-identities of the theory to show that these cannot be restored after taking away the regulators as has been proven in the case of non-anomalous theories like QED. We insist on the relation between the anomaly and the infrared problem for theories with massless particles. We have no evidence that the anomaly is related to the transformation properties of the integration measure in the path integral as is sometimes asserted in the literature but rather to the properties of triangular diagramme analysed by Adler and followers.
International Nuclear Information System (INIS)
We show at the leading order of 1/N expansion that composite gauge fields in a supersymmetric U(4n + 2)/U(4n) x SU(2) non-linear sigma model become dynamical in some range of parameters. Since the hidden local symmetry in this sigma model is identifiable with a weak SU(2) of the standard electroweak model, we suggest that the observed weak bosons W+- and Z0 are the dynamical gauge fields in our non-linear sigma model. Some phenomenological difficulties for identifing such composite fields with W+- and Z0 are also discussed. (author)
Introduction to gauge theories
Maiani, Luciano
2016-01-01
Written by three of the world's leading experts on particle physics and the standard model, including an award-winning former director general of CERN, this book provides a completely up-to-date account of gauge theories. Starting from Feynman’s path integrals, Feynman rules are derived, gauge fixing and Faddeev-Popov ghosts are discussed, and renormalization group equations are derived. Several important applications to quantum electrodynamics and quantum chromodynamics (QCD) are discussed, including the one-loop derivation of asymptotic freedom for QCD.