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.
Relative Entropy, Mixed Gauge-Gravitational Anomaly and Causality
Bhattacharyya, Arpan; Hung, Ling-Yan
2016-01-01
In this note we explored the holographic relative entropy in the presence of the 5d Chern-Simons term, which introduces a mixed gauge-gravity anomaly to the dual CFT. The theory trivially satisfies an entanglement first law. However, to quadratic order in perturbations of the stress tensor $T$ and current density $J$, there is a mixed contribution to the relative entropy bi-linear in $T$ and $J$, signalling a potential violation of the positivity of the relative entropy. Miraculously, the term vanishes up to linear order in a derivative expansion. This prompted a closer inspection on a different consistency check, that involves time-delay of a graviton propagating in a charged background, scattered via a coupling supplied by the Chern-Simons term. The analysis suggests that the time-delay can take either sign, potentially violating causality for any finite value of the CS coupling.
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.
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.
Blagojević, Milutin
2012-01-01
During the last five decades, gravity, as one of the fundamental forces of nature, has been formulated as a gauge field theory of the Weyl-Cartan-Yang-Mills type. The resulting theory, the Poincar\\'e gauge theory of gravity, encompasses Einstein's gravitational theory as well as the teleparallel theory of gravity as subcases. In general, the spacetime structure is enriched by Cartan's torsion and the new theory can accommodate fermionic matter and its spin in a perfectly natural way. The present reprint volume contains articles from the most prominent proponents of the theory and is supplemented by detailed commentaries of the editors. This guided tour starts from special relativity and leads, in its first part, to general relativity and its gauge type extensions a la Weyl and Cartan. Subsequent stopping points are the theories of Yang-Mills and Utiyama and, as a particular vantage point, the theory of Sciama and Kibble. Later, the Poincar\\'e gauge theory and its generalizations are explored and specific topi...
Gravitational Wave - Gauge Field Oscillations
Caldwell, R R; Maksimova, N A
2016-01-01
Gravitational waves propagating through a stationary gauge field transform into gauge field waves and back again. When multiple families of flavor-space locked gauge fields are present, the gravitational and gauge field waves exhibit novel dynamics. At high frequencies, the system behaves like coupled oscillators in which the gravitational wave is the central pacemaker. Due to energy conservation and exchange among the oscillators, the wave amplitudes lie on a multi-dimensional sphere, reminiscent of neutrino flavor oscillations. This phenomenon has implications for cosmological scenarios based on flavor-space locked gauge fields.
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.
Gravitational anomaly and transport phenomena.
Landsteiner, Karl; Megías, Eugenio; Pena-Benitez, Francisco
2011-07-01
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. PMID:21797593
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...
Comment on gravitational anomalies
International Nuclear Information System (INIS)
It is shown by the path integral method that the general coordinate and local Lorentz anomalies satisfy certain relations between them. The physical meaning of the cancellation of those two anomalies is clarified and it is illustrated for the fields (psi, psi sub(μ), Fsub(a)) in d = 2. We show that the use of local counter terms can be avoided if one adopts a non-linear realization of general coordinate transformations. The field representation (such as psi sub(μ) and psisub(a)) dependence of the local Lorentz anomaly is also noted. (author)
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
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
Global gravitational anomalies and transport
Chowdhury, Subham Dutta
2016-01-01
We investigate the constraints imposed by global gravitational anomalies on parity odd induced transport coefficients in even dimensions for theories with chiral fermions, gravitinos and self dual tensors. The $\\eta$-invariant for the large diffeomorphism corresponding to the $T$ transformation on a torus constraints the coefficients in the thermal effective action up to mod 2. We show that the result obtained for the parity odd transport for gravitinos using global anomaly matching is consistent with the direct perturbative calculation. In $d=6$ we see that the second Pontryagin class in the anomaly polynomial does not contribute to the $\\eta$-invariant which provides a topological explanation of this observation in the `replacement rule'. We then perform a direct perturbative calculation for the contribution of the self dual tensor in $d=6$ to the parity odd transport coefficient using the Feynman rules proposed by Gaum\\'{e} and Witten. The result for the transport coefficient agrees with that obtained usin...
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
Phase coupling gravitation: Symmetries and gauge fields
International Nuclear Information System (INIS)
We consider possible generalizations of phase coupling gravitation, a relativistic theory introduced to account for the astrophysical missing mass problem in the framework of departures from newtonian gravitation. We show that pure phase coupled gravitation cannot be gauged. However, the theory can be extended by modifying the interactions. It is then endowed with a continuous global symmetry which can be gauged. (orig.)
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.
Universally Finite Gravitational & Gauge Theories
Modesto, Leonardo
2015-01-01
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.
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
Trace and dilation anomalies in gauge theories
International Nuclear Information System (INIS)
The form of the anomaly in the trace of the energy-momentum tensor in a general theory of interacting fermions and non-Abelian gauge bosons is derived. The result is shown to involve precisely those gauge-variant operators which are known to mix with the naive trace under renormalization. The trace is shown to be soft on the mass shell if and only if the theory is at an eigenvalue of the Callan-Symanzik β function. The dilatation anomaly in the matrix element of theta/sup lambda /lambda with two electromagnetic currents (to lowest order in electromagnetism, but including all orders of the strong gauge interaction) is derived and shown to be infinitely renormalized in finite orders of strong perturbation theory. This anomaly is then shown to be canonical and given precisely by the lowest-order result provided the strong interactions are summed to all orders before going to the limit of physical space-time dimensions
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
Gravitational Lorentz anomaly from the overall formula in 2-dimensions
International Nuclear Information System (INIS)
In this letter we show that the overlap formulation of chiral gauge theories correctly reproduces the gravitational Lorentz anomaly in 2-dimensions. This formulation has been recently suggested as a solution to the fermion doubling problem on the lattice. The well known response to general coordinate transformations of the effective action of Weyl fermions coupled to gravity in 2-dimensions can also be recovered. (author). 7 refs
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)
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
Quantum gravitational anomaly as a dark matter
Kazinski, P. O.
2015-01-01
The general properties of a perfect relativistic fluid resulting from the quantum gravitational anomaly are investigated. It is found that, in the limit of a weak gravitational field, this fluid possesses a polytropic equation of state characterized by two universal constants: the polytropic constant and the natural polytropic index. Based on the astrophysical data, the estimates for the polytropic constant are given. It is shown that this fluid can describe a considerable part of the cold da...
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.
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.
Gravitational Shielding Effects in Gauge Theory of Gravity
Wu, N
2003-01-01
In 1992, E.E.Podkletnov and R.Nieminen find that, under certain conditions, ceramic superconductor with composite structure has revealed weak shielding properties against gravitational force. In classical Newton's theory of gravity and even in Einstein's general theory of gravity, there are no grounds of gravitational shielding effects. But in quantum gauge theory of gravity, the gravitational shielding effects can be explained in a simple and natural way. In quantum gauge theory of gravity, gravitational gauge interactions of complex scalar field can be formulated based on gauge principle. After spontaneous symmetry breaking, if the vacuum of the complex scalar field is not stable and uniform, there will be a mass term of gravitational gauge field. When gravitational gauge field propagates in this unstable vacuum of the complex scalar field, it will decays exponentially, which is the nature of gravitational shielding effects. The mechanism of gravitational shielding effects is studied in this paper, and some...
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 Goldstone fields from affine gauge theory
Tresguerres, R
2000-01-01
In order to facilitate the application of standard renormalization techniques, gravitation should be decribed, if possible, in pure connection formalism, as a Yang-Mills theory of a certain spacetime group, say the Poincare or the affine group. This embodies the translational as well as the linear connection. However, the coframe is not the standard Yang-Mills type gauge field of the translations, since it lacks the inhomogeneous gradient term in the gauge transformations. By explicitly restoring the "hidden" piece responsible for this behavior within the framework of nonlinear realizations, the usual geometrical interpretation of the dynamical theory becomes possible, and in addition one can avoid the metric or coframe degeneracy which would otherwise interfere with the integrations within the path integral. We claim that nonlinear realizations provide a general mathematical scheme clarifying the foundations of gauge theories of spacetime symmetries. When applied to construct the Yang-Mills theory of the aff...
SU(N) global gauge anomalies in even dimensions
International Nuclear Information System (INIS)
Assuming that the representations of the SU(N) (N = n,n-1) gauge groups in (D = 2n)-dimensional space are chosen to be free of local (perturbative) anomalies, i.e., Tr F/sup n//sup +1/ = 0, the following is proved by group theory: (1) For SU(n), there will be no global (nonperturbative) gauge anomalies in D = 4k+2 and at most Z2 global anomalies in D = 4k and (2) for SU(n-1), there exist no global gauge anomalies if D = 2n≥6. The topological argument is given for why, for any gauge group, the global anomaly is at most Z2 and in D = 4k+2 no global gauge anomalies exist for a self-contragredient representation
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.
Quantum gravitational anomaly as a dark matter
Kazinski, P O
2015-01-01
The general properties of a perfect relativistic fluid resulting from the quantum gravitational anomaly are investigated. It is found that, in the limit of a weak gravitational field, this fluid possesses a polytropic equation of state characterized by two universal constants: the polytropic constant and the natural polytropic index. Based on the astrophysical data, the estimates for the polytropic constant are given. It is shown that this fluid can describe a considerable part of the cold dark matter. The quantum theory of such a fluid is constructed in the framework of the background field method. The Ward identities associated with the entropy and vorticity conservation laws are derived. The leading gradient corrections to the pressure of the perfect fluid are found and the restrictions on their form are obtained. These restrictions guarantee, in particular, the absence of ghosts in the model. The second order nonlinear corrections to the equations of motion of a perfect relativistic fluid are analyzed and...
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; Rachwał, Lesław
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.
Hawking Radiation via Gravitational Anomalies in Non-spherical Topologies
Papantonopoulos, Eleftherios; Skamagoulis, Petros
2008-01-01
We study the method of calculating the Hawking radiation via gravitational anomalies in gravitational backgrounds of constant negative curvature. We apply the method to topological black holes and also to topological black holes conformally coupled to a scalar field.
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.
Maps for currents and anomalies in noncommutative gauge theories
Banerjee, Rabin; Kumar, Kuldeep
2004-01-01
We derive maps relating currents and their divergences in non-abelian U(N) noncommutative gauge theory with the corresponding expressions in the ordinary (commutative) description. For the U(1) theory, in the slowly-varying-field approximation, these maps are also seen to connect the star-gauge-covariant anomaly in the noncommutative theory with the standard Adler--Bell--Jackiw anomaly in the commutative version. For arbitrary fields, derivative corrections to the maps are explicitly computed...
Shih, Sheng-Yu Darren
2014-01-01
This thesis covers two distinct parts: Holomorphic Anomaly in Gauge Theory on ALE Space and Freudenthal Gauge Theory.In part I, I presented a concise review of the Seiberg-Witten curve, Nekrasov's background, geometric engineering and the holomorphic anomaly equation followed by my published work: Holomorphic Anomaly in Gauge Theory on ALE Space, where an deformed N = 2 SU(2) gauge theory on A1 space and its five dimension lift is studied.We find that the partition functions can be reproduced...
A new anomaly-free gauged supergravity in six dimensions
International Nuclear Information System (INIS)
We present a new anomaly-free gauged N = 1 supergravity model in six dimensions. The gauge group is E7 - G2 x U(1)R, with all hyperinos transforming in the product representation (56, 14). The theory admits monopole compactifications to R4 x S2, leading to D = 4 effective theories with broken supersymmetry and massless fermions. (author)
Ghost number anomaly in the Polyakov's light-cone gauge
International Nuclear Information System (INIS)
The conformal (Weyl) anomaly of the ghost-anti-ghost system in the two-dimentional quantum gravity is calculated. A background covariant formalism allows us to treat the Polyakov's light-cone gauge in a systematic way. The anomaly gives a contribution to the central charge, -28, which agrees with the result of Kniznik, Polyakov and Zamolodchikov. The ghost number anomaly is also calculated, and the metric corrections to the naive ghost number current are given. It is suggested that a general scalar density in the light-cone gauge carries a screening ghost number. (author)
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 gravitating matter is posi...
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
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...
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)
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...
Functorial QFT, Gauge Anomalies and the Dirac Determinant Bundle
Mickelsson, J; Mickelsson, Jouko; Scott, Simon
1999-01-01
Using properties of the determinant line bundle for a family of elliptic boundary value problems, we explain how the Fock space functor defines an axiomatic quantum field theory which formally models the Fermionic path integral. The 'sewing axiom' of the theory arises as an algebraic pasting law for the determinant of the Dirac operator. We show how representations of the boundary gauge group fit into this description and that this leads to a Fock functor description of certain gauge anomalies.
Spherically-symmetric gravitational fields in the metric-affine gauge theory of gravitation
Minkevich, A. V.; Vasilevski, Yu. G.
2003-01-01
Geometric structure of spherically-symmetric space-time in metric-affine gauge theory of gravity is studied. Restrictions on curvature tensor and Bianchi identities are obtained. By using certain simple gravitational Lagrangian the solution of gravitational equations for vacuum spherically-symmetric gravitational field is obtained.
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.)
The physical observer II: Gauge and diff anomalies
Larsson, T. A.
2008-01-01
In a companion paper we studied field theory in the presence of a physical observer with quantum dynamics. Here we describe the most striking consequence of this assumption: new gauge and diff anomalies arise. The relevant cocycles depend on the observer's spacetime trajectory and can hence not appear in QFT, where this quantity is never introduced. Diff anomalies necessarily arise in every locally nontrivial, non-holographic theory of quantum gravity. Cancellation of the divergent parts of t...
Shih, Sheng-Yu Darren
This thesis covers two distinct parts: Holomorphic Anomaly in Gauge Theory on ALE Space and Freudenthal Gauge Theory. In part I, I presented a concise review of the Seiberg-Witten curve, Nekrasov's background, geometric engineering and the holomorphic anomaly equation followed by my published work: Holomorphic Anomaly in Gauge Theory on ALE Space, where an deformed N = 2 SU(2) gauge theory on A1 space and its five dimension lift is studied. We find that the partition functions can be reproduced via special geometry and the holomorphic anomaly equation. Schwinger type integral expressions for the boundary conditions at the monopole/dyon point in moduli space are inferred. The interpretation of the five dimensional partition function as the partition function of a refined topological string on A1x(local P1 x P1) is suggested. In part II, I give a comprehensive review of the Freudenthal Triple System, including Freudenthal's orginal construction from Jordan Triple Systems and its relation to Lie algebra, Yang-Baxter equation, and 4d N = 2 BPS black holes, where the novel Freudenthal-dual was discovered. I also present my published work on the Freudenthal Gauge Theory, where we construct the most generic gauge theory admitting F-dual, and prove a no-go theorem that forbids coupling of a F-dual invariant gauge theory to supersymmetry.
Non-abelian gauge extensions for B-decay anomalies
Boucenna, Sofiane M; Fuentes-Martin, Javier; Vicente, Avelino; Virto, Javier
2016-01-01
We study the generic features of minimal gauge extensions of the Standard Model in view of recent hints of lepton-flavor non-universality in $B$-decays. We classify the posible models according to the symmetry-breaking pattern and the source of flavor non-universality. We find that in viable models the $\\mathrm{SU(2)}_L$ factor is embedded non-trivially in the extended gauge group, and that gauge couplings should be universal, hinting to the presence of new degrees of freedom sourcing non-universality. We construct an explicit model satisfying our criteria, and discuss the role of gauge mixing and its phenomenological relevance in the context of the anomalies.
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.
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.)
Gauge Gravitation Theory. What is the Geometry of the World?
Sardanashvily, G.
1994-01-01
When joined the unified gauge picture of fundamental interactions, the gravitation theory leads to geometry of a space-time which is far from simplicity of pseudo-Riemannian geometry of Einstein's General Relativity. This is geometry of the affine-metric composite dislocated manifolds. The goal is modification of the familiar equations of a gravitational field and entirely the new equations of its deviations. In the present brief, we do not detail the mathematics, but discuss the reasons why ...
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.
Gravitational anomalies, gerbes, and hamiltonian quantization
Ekstrand, C.; Mickelsson, J.
1999-01-01
In [Carey, A.L., J. Mickelsson, and M. K. Murray: Comm. Math. Phys. 183, 707 (1997)] Schwinger terms in hamiltonian quantization of chiral fermions coupled to vector potentials were computed, using some ideas from the theory of gerbes, with the help of the family index theorem for a manifold with boundary. Here, we generalize this method to include gravitational Schwinger terms.
Gravitational anomalies, gerbes and hamiltonian quantization
Ekstrand, C
2000-01-01
In [Carey, A.L., J. Mickelsson, and M. K. Murray: Comm. Math. Phys. 183, 707 (1997)] Schwinger terms in hamiltonian quantization of chiral fermions coupled to vector potentials were computed, using some ideas from the theory of gerbes, with the help of the family index theorem for a manifold with boundary. Here, we generalize this method to include gravitational Schwinger terms.
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.)
Gravitational F-terms through anomaly equations and deformed chiral rings
International Nuclear Information System (INIS)
We study effective gravitational F-terms, obtained by integrating an U(N) adjoint chiral superfield Φ coupled to the N = 1 gauge chiral superfield Wα and supergravity, to arbitrary orders in the gravitational background. The latter includes in addition to the N = 1 Weyl superfield Gαβγ, the self-dual graviphoton field strength Fαβ of the parent, broken N = 2 theory. We first study the chiral ring relations resulting from the above non-standard gravitational background and find agreement, for gauge invariant operators, with those obtained from the dual closed string side via Bianchi identities for N = 2 supergravity coupled to vector multiplets. We then derive generalized anomaly equations for connected correlators on the gauge theory side, which allow us to solve for the basic one-point function 2/(z - Φ)> to all orders in F2. By generalizing the matrix model loop equation to the generating functional of connected correlators of resolvents, we prove that the gauge theory result coincides with the genus expansion of the associated matrix model, after identifying the expansion parameters on the two sides. (author)
Gravitational Leptogenesis in the Axion Inflation with an SU(2) gauge field
Maleknejad, Azadeh
2016-01-01
We present a natural leptogenesis mechanism in models of axion inflation with a classical SU(2) gauge field. The gauge field is coupled to the axion with a Chern-Simons interaction and comprises a tiny fraction of the total energy, $\\frac{\\rho_{_{\\rm YM}}}{\\rho_{_{\\rm tot}}}\\lesssim\\epsilon^2$. However, it has spin-2 fluctuations which break the parity and leads to the generation of chiral gravitational waves during inflation. By the gravitational anomaly in SM, it naturally creates a net lepton number density, sufficient to explain the matter asymmetry. We show that this mechanism can generate the observed value of baryon to photon number density in a natural range of parameters and yet has a small chiral tensor power spectrum on large scales.
Diffeomorphism cohomology and gravitational anomalies: Pt. 2
International Nuclear Information System (INIS)
Using the spectral sequencies technique, it is studied the local polynomial cohomology space of the operator S deltasub(GAMMAsub(c1))sup(L) - Csup(lambda)(x)deltasub(lambda) -deltasub(lambda)Csup(lambda)(x), which is isomorphic to the local functional cohomology of the operator deltasub(GAMMAsub(c1))sup(L) which induces general co-ordinate transformations in four-dimensional space-time. In the Faddeev-Popov (PHI II) charge-one sector, it is found that all the anomalies have the form Δ(x) deltasub(lambda)Csup(lambda)(x)Δ-circumflex(x), where Csup(lambda)(x) is the ghost field, and Δ-circumflex(x) is a PHI II charge-zero anomaly
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
Algebraic structure of chiral anomalies
International Nuclear Information System (INIS)
I will describe first the algebraic aspects of chiral anomalies, exercising however due care about the topological delicacies. I will illustrate the structure and methods in the context of gauge anomalies and will eventually make contact with results obtained from index theory. I will go into two sorts of generalizations: on the one hand, generalizing the algebraic set up yields e.g. gravitational and mixed gauge anomalies, supersymmetric gauge anomalies, anomalies in supergravity theories; on the other hand most constructions applied to the cohomologies which characterize anomalies easily extend to higher cohomologies. Section II is devoted to a description of the general set up as it applies to gauge anomalies. Section III deals with a number of algebraic set ups which characterize more general types of anomalies: gravitational and mixed gauge anomalies, supersymmetric gauge anomalies, anomalies in supergravity theories. It also includes brief remarks on σ models and a reminder on the full BRST algebra of quantized gauge theories
Gauge field, strings, solitons, anomalies and the speed of life
Niemi, Antti J
2014-01-01
It's been said that "mathematics is biology's next microscope, only better; biology is mathematics' next physics, only better". Here we aim for something even better. We try to combine mathematical physics and biology into a picoscope of life. For this we merge techniques which have been introduced and developed in modern mathematical physics, largely by Ludvig Faddeev to describe objects such as solitons and Higgs and to explain phenomena such as anomalies in gauge fields. We propose a synthesis that can help to resolve the protein folding problem, one of the most important conundrums in all of science. We apply the concept of gauge invariance to scrutinize the extrinsic geometry of strings in three dimensional space. We evoke general principles of symmetry in combination with Wilsonian universality and derive an essentially unique Landau-Ginzburg energy that describes the dynamics of a generic string-like configuration in the far infrared. We observe that the energy supports topological solitons, that perta...
Gravitational self-force from radiation-gauge metric perturbations
Pound, Adam; Barack, Leor
2014-01-01
Calculations of the gravitational self-force (GSF) in curved spacetime require as input the metric perturbation in a sufficiently regular gauge. A basic challenge in the program to compute the GSF for orbits around a Kerr black hole is that the standard procedure for reconstructing the perturbation is formulated in a class of radiation gauges, in which the particle singularity is non-isotropic and extends away from the particle's location. Here we present two practical schemes for calculating the GSF using a radiation-gauge reconstructed metric as input. The schemes are based on a detailed analysis of the local structure of the particle singularity in the radiation gauges. We identify 3 types of radiation gauges: two containing a radial string-like singularity emanating from the particle, either in one direction ("half-string" gauges) or both directions ("full-string" gauges); and a third type containing no strings but with a jump discontinuity across a surface intersecting the particle. Based on a flat-space...
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
Spontaneous symmetry breaking in the gauge gravitation theory
International Nuclear Information System (INIS)
The specificity of spontaneous symmetry breaking in the gauge theory of gravity is that Dirac fermion fields possess only exact Lorentz symmetries. As a consequence, different tetrad gravitational fields h and h' define nonisomorphic representations of cotangent vectors to a space-time manifold X4 by Dirac's γ-matrices on fermion fields. One needs these representations in order to construct the Dirac operator. Dirac fermion fields therefore must be considered only in a pair with a certain tetrad gravitational field. We describe the complex of such fermion-gravitational pairs by means of a spinor fibre bundle over the generalized coordinate space X4 x (GL+(4, R)/SO(3,1)). We show that gravitational fields h fail to form an affine space modelled after any vector space of deviations h-h' of some background field h. They therefore fail to be quantized in accordance with the familiar quantum field theory. However, one can consider nongravitational deviations σ of h such that h+σ is not a gravitational field. These deviations form a vector space, i.e. they satisfy the superposition principle. Their Lagrangian, however, differs from familiar Lagrangians of gravitation theory. For instance, it contains mass-like terms. (author). 19 refs
Gravitational anomalies and one-dimensional behavior of black holes
Majhi, Bibhas Ranjan
2015-12-01
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 ({dot{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 {dot{S}} on the power is {dot{S}}∝ P^{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 Pendry'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
Gravitational anomalies and one-dimensional behavior of black holes
Energy Technology Data Exchange (ETDEWEB)
Majhi, Bibhas Ranjan [Indian Institute of Technology Guwahati, Department of Physics, Guwahati, Assam (India)
2015-12-15
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 ∝ P{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 Pendry's formula, while in the latter situation its value decreases. (orig.)
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 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{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 .} ∝P{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 Pendry’s formula, while in the latter situation its value decreases.
The UV and IR Origin of Nonabelian Chiral Gauge Anomalies on Noncommutative Space-time
Martín, C P
2001-01-01
We discuss both the UV and IR origin of the one-loop triangle gauge anomalies for noncommutative nonabelian chiral gauge theories with fundamental, adjoint and bi-fundamental fermions for U(N) groups. We find that gauge anomalies only come from planar triangle diagrams, the non-planar triangle contributions giving rise to no breaking of the Ward identies. Generally speaking, theories with fundamental and bi-fundamental chiral matter are anomalous. Theories with only adjoint chiral fermions are anomaly free.
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
Trace anomaly, massless scalars, and the gravitational coupling of QCD
Armillis, Roberta; Corianò, Claudio; Delle Rose, Luigi
2010-09-01
The anomalous effective action describing the coupling of gravity to a non-Abelian gauge theory can be determined by a variational solution of the anomaly equation, as shown by Riegert long ago. It is given by a nonlocal expression, with the nonlocal interaction determined by the Green’s function of a conformally covariant operator of fourth order. In recent works it has been shown that this interaction is mediated by a simple pole in an expansion around a Minkowski background, coupled in the infrared in the massless fermion limit. This result relies on the local formulation of the original action in terms of two auxiliary fields, one physical scalar and one ghost, which take the role of massless composite degrees of freedom. In the gravity case, the two scalars have provided ground in favor of some recent proposals of an infrared approach to the solution of the dark energy problem, entirely based on the behavior of the vacuum energy at the QCD phase transition. As a test of this general result, we perform a complete one-loop computation of the effective action describing the coupling of a non-Abelian gauge theory to gravity. We confirm the appearance of an anomaly pole which contributes to the trace part of the TJJ correlator and of extra poles in its trace-free part, in the quark and gluon sectors, describing the coupling of the energy-momentum tensor (T) to two non-Abelian gauge currents (J).
Trace anomaly, massless scalars, and the gravitational coupling of QCD
International Nuclear Information System (INIS)
The anomalous effective action describing the coupling of gravity to a non-Abelian gauge theory can be determined by a variational solution of the anomaly equation, as shown by Riegert long ago. It is given by a nonlocal expression, with the nonlocal interaction determined by the Green's function of a conformally covariant operator of fourth order. In recent works it has been shown that this interaction is mediated by a simple pole in an expansion around a Minkowski background, coupled in the infrared in the massless fermion limit. This result relies on the local formulation of the original action in terms of two auxiliary fields, one physical scalar and one ghost, which take the role of massless composite degrees of freedom. In the gravity case, the two scalars have provided ground in favor of some recent proposals of an infrared approach to the solution of the dark energy problem, entirely based on the behavior of the vacuum energy at the QCD phase transition. As a test of this general result, we perform a complete one-loop computation of the effective action describing the coupling of a non-Abelian gauge theory to gravity. We confirm the appearance of an anomaly pole which contributes to the trace part of the TJJ correlator and of extra poles in its trace-free part, in the quark and gluon sectors, describing the coupling of the energy-momentum tensor (T) to two non-Abelian gauge currents (J).
Tang, Yong
2011-01-01
We perform an explicit one-loop calculation for the gravitational contributions to the two-, three- and four-point gauge Green's functions with paying attention to the quadratic divergences. It is shown for the first time in the diagrammatic calculation that the Slavnov-Taylor identities are preserved even if the quantum graviton effects are included at one-loop level, such a conclusion is independent of the choice of regularization schemes. We also present a regularization scheme independent calculation based on the gauge condition independent background field framework of Vilkovisky-DeWitt's effective action with focusing on both the quadratic divergence and quartic divergence that is not discussed before. With the harmonic gauge condition, the results computed by using the traditional background field method can consistently be recovered from the Vilkovisky-DeWitt's effective action approach by simply taking a limiting case, and are found to be the same as the ones yielded by the diagrammatic calculation. ...
Tang, Yong; Wu, Yue-Liang
2011-11-01
We perform an explicit one-loop calculation for the gravitational contributions to the two-, three- and four-point gauge Green's functions with paying attention to the quadratic divergences. It is shown for the first time in the diagrammatic calculation that the Slavnov-Taylor identities are preserved even if the quantum graviton effects are included at one-loop level, such a conclusion is independent of the choice of regularization schemes. We also present a regularization scheme independent calculation based on the gauge condition independent background field framework of Vilkovisky-DeWitt's effective action with focusing on both the quadratic divergence and quartic divergence that is not discussed before. With the harmonic gauge condition, the results computed by using the traditional background field method can consistently be recovered from the Vilkovisky-DeWitt's effective action approach by simply taking a limiting case, and are found to be the same as the ones yielded by the diagrammatic calculation. As a consequence, in all the calculations, the symmetry-preserving and divergent-behavior-preserving loop regularization method can consistently lead to a nontrivial gravitational contribution to the gauge coupling constant with an asymptotic free power-law running at one loop near the Planck scale.
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.
Gravitational Self-force in a Radiation Gauge
Keidl, Tobias S; Friedman, John L; Kim, Dong-Hoon; Price, Larry R
2010-01-01
In this, the first of two companion papers, we present a method for finding the gravitational self-force in a radiation gauge for a particle moving on a geodesic in a Schwarzschild or Kerr spacetime. The method involves a mode-sum renormalization of a spin-weight $\\pm 2$ perturbed Weyl scalar and the subsequent reconstruction from a Hertz potential of the renormalized perturbed metric. We show that the Hertz potential is uniquely specified by the requirement that it have no angular harmonics with $\\ell\\leq 2$. The resulting perturbed metric is singular only at the position of the particle: It is smooth on the axis of symmetry. An extension of an earlier result by Wald is needed to show that the perturbed metric is determined up to a gauge transformation and an infinitesimal change in the black hole mass and spin. We show that the singular behavior of the metric and self-force has the same power-law behavior in $L=\\ell+1/2$ as in a Lorenz gauge (with different coefficients). We compute the singular Weyl scalar...
Massive to gauge field reduction and gravitational wave zone information
Deser, S
2016-01-01
We show explicitly that massive, Abelian, vector, just like (properly defined) massive tensor, fields limit smoothly to their massless, gauge, versions: they emit only maximal helicity radiation and mediate Coulomb and (special relativistic) Newtonian, forces between their (conserved) sources. Our main motivation, though, is to show that the recent gravitational wave detection probably cannot directly rule out very long-range gravity: Even though the waves were emitted in a strong field regime, their being detected in the weak field wave zone means the above equivalences apply. There remains the, not unlikely, possibility that no strong field generation of radiation in massive models can reproduce the observed ring-down patterns. Separately, the smooth linear limiting behaviors show that the discontinuity lies not in the mass alone, but rather in Abelian versus non-Abelian, Yang-Mills and General Relativity, regimes, whose respective massive versions are known to be non-physical.
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.)
Gravitational Waves in Bouncing Cosmologies from Gauge Field Production
Ben-Dayan, Ido
2016-01-01
We calculate the gravitational waves (GW) spectrum produced in various Early Universe scenarios from gauge field sources, thus generalizing earlier inflationary calculations to bouncing cosmologies. We consider generic couplings between the gauge fields and the scalar field dominating the energy density of the Universe. We analyze the requirements needed to avoid a backreaction that will spoil the background evolution. When the scalar is coupled only to $F \\tilde F$ term, the sourced GW spectrum is exponentially enhanced and parametrically the square of the vacuum fluctuations spectrum, ${\\cal P}^s_T\\sim ({\\cal P}^v_T)^2$, giving an even bluer spectrum than the standard vacuum one. When the scalar field is also coupled to $F^2$ term, the amplitude is still exponentially enhanced, but the spectrum can be arbitrarily close to scale invariant (still slightly blue), $n_T\\gtrsim 0$, that is distinguishable form the slightly red inflationary one. Hence, we have a proof of concept of observable GW on CMB scales in a...
Resolution of axial anomaly problem in supersymmetric gauge theories
International Nuclear Information System (INIS)
The explicit form of transformation is found which converters the operators, involved in axial anomaly, from the renormalization scheme obeying the Adler-BaAdeen theorem to a supersymmetric one. It is shown that there is no contradiction between axial current and superconformal anomalies. In supersymmetric scheme the axial current and its anomaly belong to the corresponding supermultiplets
Anselmi, Damiano
2015-05-01
We prove the Adler-Bardeen theorem in a large class of general gauge theories, including nonrenormalizable ones. We assume that the gauge symmetries are general covariance, local Lorentz symmetry, and Abelian and non-Abelian Yang-Mills symmetries, and that the local functionals of vanishing ghost numbers satisfy a variant of the Kluberg-Stern-Zuber conjecture. We show that if the gauge anomalies are trivial at one loop, for every truncation of the theory there exists a subtraction scheme where they manifestly vanish to all orders, within the truncation. Outside the truncation the cancellation of gauge anomalies can be enforced by fine-tuning local counterterms. The framework of the proof is worked out by combining a recently formulated chiral dimensional regularization with a gauge invariant higher-derivative regularization. If the higher-derivative regularizing terms are placed well beyond the truncation, and the energy scale Λ associated with them is kept fixed, the theory is superrenormalizable and has the property that, once the gauge anomalies are canceled at one loop, they manifestly vanish from two loops onwards by simple power counting. When the Λ divergences are subtracted away and Λ is sent to infinity, the anomaly cancellation survives in a manifest form within the truncation and in a nonmanifest form outside. The standard model coupled to quantum gravity satisfies all the assumptions, so it is free of gauge anomalies to all orders.
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
One-loop anomalies and Wess-Zumino terms for general gauge theories
International Nuclear Information System (INIS)
One-loop anomalies and their dependence on antifields for general gauge theories are investigated within a Pauli-Villars regularization scheme. For on-shell theories i.e. with open algebras or on-shell reducible theories, the antifield dependence is cohomologically non-trivial. The associated Wess-Zumino term depends also on antifields. In the classical basis the antifield-independent part of the WZ term is expressed in terms of the anomaly and finite gauge transformations by introducing gauge degrees of freedom as the extra dynamical variables. The complete WZ term is reconstructed from the antifield-independent part. (orig.)
Gravitational anomalies in higher dimensional Riemann-Cartan space
International Nuclear Information System (INIS)
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
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 β-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)
On the problem of axial anomaly in supersymmetric gauge theories
International Nuclear Information System (INIS)
The explicit relation is found between the axial current obeying the Adler-Bardeen theorem and the supersymmetric one belonging to a supermultiplet. It is shown that the axial and superconformal anomalies are consistent in all orders of perturbation theory
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.
Axial anomaly in the presence of the Aharonov-Bohm gauge field
International Nuclear Information System (INIS)
The axial anomaly for Euclidean Dirac fermions in the presence of a background Aharonov-Bohm gauge potential was computed. The non-perturbative result depends on the self-adjoint extensions of the Dirac operator. The role of the quantum mechanical parameters involved in the expression for the axial anomaly is discussed. A derivation of the effective action by means of the stereographic projection is also considered. (authors). 14 refs
Chiral anomalies in higher-derivative supersymmetric 6D gauge theories
International Nuclear Information System (INIS)
We show that the recently constructed higher-derivative 6D SYM theory involves internal chiral anomaly breaking gauge invariance. The anomaly is cancelled when adding to the theory an adjoint matter hyper-multiplet. One shows that as the effective charge grows at high energies, the theories are not consistently defined nonperturbatively. Constructing a nontrivial 6D theory that would be internally consistent both perturbatively and nonperturbatively remains a major challenge. (author)
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
International Nuclear Information System (INIS)
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
International Nuclear Information System (INIS)
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)
On gravitational dressing of 2D field theories in chiral gauge
International Nuclear Information System (INIS)
After giving a pedagogical review of the chiral gauge approach to 2D gravity, with particular emphasis on the derivation of the gravitational Ward identities, we discuss in some detail the interpretation of matter correlation functions coupled to gravity in chiral gauge. We argue that in chiral gauge no explicit gravitational dressing factor, analogue to the Liouville exponential in conformal gauge, is necessary for left-right symmetric matter operators. In particular, we examine the gravitationally dressed four-point correlation function of products of left and right fermions. We solve the corresponding gravitational Ward identity exactly: in the presence of gravity this four-point function exhibits a logarithmic short-distance singularity, instead of the power-law singularity in the absence of gravity. This rather surprising effect is non-perturbative in the gravitational coupling and is a sign for logarithms in the gravitationally dressed operator product expansions. We also discuss some perturbative evidence that the chiral Gross-Neveu model may remain integrable when coupled to gravity. (orig.)
Adler-Bardeen theorem and manifest anomaly cancellation to all orders in gauge theories
Anselmi, Damiano
2014-10-01
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 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.
Adler-Bardeen theorem and manifest anomaly cancellation to all orders in gauge theories
Energy Technology Data Exchange (ETDEWEB)
Anselmi, Damiano [Pisa Univ. (Italy). Dipt. di Fisica ' ' Enrico Fermi' '
2014-10-15
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.)
Adler-Bardeen theorem and manifest anomaly cancellation to all orders in gauge theories
International Nuclear Information System (INIS)
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.)
International Nuclear Information System (INIS)
We show that ghosts in gauge theories can be interpreted as Maurer-Cartan forms in the infinite dimensional group G of gauge transformations. We examine the cohomology of the Lie algebra of G and identify the coboundary opeator with the BRS operator. We describe the anomalous terms encountered in the renormalization of gauge theories (triangle anomalies) as elements of these cohomology groups. (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.
Gauge invariance and the detection of gravitational radiation
Garfinkle, David
2005-01-01
The detection of gravitational radiation raises some subtle issues having to do with the coordinate invariance of general relativity. This paper explains these issues and their resolution by using an analogy with the Aharonov-Bohm effect of quantum mechanics.
Theory of a gauge gravitational field at localization of the Einstein group
International Nuclear Information System (INIS)
Theory of a gauge gravitational field when localizing a group of movements of the Einstein homogeneous static Universe (the R x SO Einstein group (4)) has been formulated. Proceeding from tetrade components of the Einstein Universe the relation between the Riemann metrics and gauge fields of the Einstein group has been established. Metric coherence with torsion transforming to the Kristoffel coherence of the Einstein Universe has been found when switching out gauge fields. It is shown that within the limit of infinite radius of the Einstein Universe curvature the given Einstein-invariant gauge theory transforms to the tetrade gravitation theory with localized triade rotations. Exact solutions in the form of nonsingular cosmological models have been obtained
On the Heterotic Effective Action at One-Loop, Gauge Couplings and the Gravitational Sector
E. Kiritsis(Physics Department, University of Crete, P.O. Box 2208, 71003 Heraklion, Crete, Greece); Kounnas, C.; Petropoulos, M.; Rizos, J.
1996-01-01
We present in detail the procedure for calculating the heterotic one-loop effective action. We focus on gravitational and gauge couplings. We show that the two-derivative couplings of the gravitational sector are not renormalized at one loop when the ground state is supersymmetric. Arguments are presented that this non-renormalization theorem persists to all orders in perturbation theory. We also derive the full one-loop correction to the gauge coupling. For a class of $N=2$ ground states, na...
The geometrical and gauge structure of a generalized theory of gravitation
International Nuclear Information System (INIS)
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 ...
Anselmi, Damiano
2015-01-01
We prove the Adler-Bardeen theorem in a large class of general gauge theories, including nonrenormalizable ones. We assume that the gauge symmetries are general covariance, local Lorentz symmetry and Abelian and non-Abelian Yang-Mills symmetries, and that the local functionals of vanishing ghost number satisfy a variant of the Kluberg-Stern--Zuber conjecture. We show that if the gauge anomalies are trivial at one loop, for every truncation of the theory there exists a subtraction scheme where they manifestly vanish to all orders, within the truncation. Outside the truncation the cancellation of gauge anomalies can be enforced by fine-tuning local counterterms. The framework of the proof is worked out by combining a recently formulated chiral dimensional regularization with a gauge invariant higher-derivative regularization. If the higher-derivative regularizing terms are placed well beyond the truncation, and the energy scale $\\Lambda$ associated with them is kept fixed, the theory is super-renormalizable and...
Hawking radiation from gravity's rainbow via gravitational anomaly
International Nuclear Information System (INIS)
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
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.
Gauge theory duals of black hole – black string transitions of gravitational theories on a circle
International Nuclear Information System (INIS)
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 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.
Conservation laws in the SLsub(2,C) gauge theory of gravitation
International Nuclear Information System (INIS)
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.
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.
Gravitational duality in MacDowell-Mansouri gauge theory
Garca-Compen, H.; Obregn, O.; Ramrez, 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.
Gauge fields arising from spacetime symmetries and gravitational theories. I
International Nuclear Information System (INIS)
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
Trumpet solution from spherical gravitational collapse with puncture gauges
International Nuclear Information System (INIS)
We investigate the stationary end state obtained by evolving a collapsing spherical star with the gauges routinely adopted to study puncture black holes. We compare the end state of the collapse with the trumpet solution found in the evolution of a single wormhole slice and show that the two solutions closely agree. We demonstrate that the agreement is caused by the use of the Gamma-driver shift condition, which allows the matter to fall inwards into a region of spacetime that is not resolved by the numerical grid, and which simultaneously finds the stationary coordinates of the trumpet outside the matter.
International Nuclear Information System (INIS)
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.
Lateral density anomalies and the earth's gravitational field
Lowrey, B. E.
1978-01-01
The interpretation of gravity is valuable for understanding lithospheric plate motion and mantle convection. Postulated models of anomalous mass distributions in the earth and the observed geopotential as expressed in the spherical harmonic expansion are compared. In particular, models of the anomalous density as a function of radius are found which can closely match the average magnitude of the spherical harmonic coefficients of a degree. These models include: (1) a two-component model consisting of an anomalous layer at 200 km depth (below the earth's surface) and at 1500 km depth (2) a two-component model where the upper component is distributed in the region between 1000 and 2800 km depth, and(3) a model with density anomalies which continuously increase with depth more than an order of magnitude.
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 general differentia...
Anomaly-free discrete gauge symmetries in Froggatt-Nielsen models
Energy Technology Data Exchange (ETDEWEB)
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.)
Axial vacuum symmetry of the unified gauge theories with the gravitational mechanism of instability
International Nuclear Information System (INIS)
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)
The Adler-Bardeen theorem for the axial U(1) anomaly in a general non-Abelian gauge theory
International Nuclear Information System (INIS)
A general, regularization-scheme-independent proof of the nonrenormalization theorem for the anomaly of a U(1) axial current in a renormalizable gauge theory is presented. The gauge group may be an arbitrary compact Lie group. The validity of the theorem is traced back to some finiteness properties allowing for a well defined but particular choice of the anomaly operators. Whereas in the case of a purely Abelian gauge group this choice amounts to a physically reasonable normalization at zero energy, the general non-Abelian case awaits a deeper understanding
The Adler-Bardeen theorem for the axial U(1) anomaly in a general non-Abelian gauge theory
Energy Technology Data Exchange (ETDEWEB)
Lucchesi, C.; Piguet, O.; Sibold, K.
1987-04-01
A general, regularization-scheme-independent proof of the nonrenormalization theorem for the anomaly of a U(1) axial current in a renormalizable gauge theory is presented. The gauge group may be an arbitrary compact Lie group. The validity of the theorem is traced back to some finiteness properties allowing for a well defined but particular choice of the anomaly operators. Whereas in the case of a purely Abelian gauge group this choice amounts to a physically reasonable normalization at zero energy, the general non-Abelian case awaits a deeper understanding.
All-loop gauge couplings from anomaly cancellation in string effective theories
International Nuclear Information System (INIS)
We derive, to all orders in perturbation theory, the E8 gauge coupling and the modified dilaton-axion Kaehler potential for the effective theories of a class of d=4, N=1 heterotic string models. The derivation relies on an extended version of the Green-Schwarz anomaly cancellation mechanism, and exploits target-space duality invariance. Although we deal with field-dependent effective gauge couplings and scales in a non-renormalizable supergravity theory, we derive for them a renormalization group equation as a relation among dynamical fields. When expectation values of these fields are considered, our results agree with those previously obtained in renormalizable theories with N=1 global supersymmetry. We finally comment on possible generalizations of the present results. (orig.)
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...
Post-Newtonian effects in the quadratic Poincaré gauge theory of gravitation
Gladchenko, M. S.; Zhytnikov, V. V.
1994-10-01
The post-Newtonian approximation of the Poincaré gauge theory (PGT) of gravitation with an arbitrary Lagrangian is calculated. The constraints on the parameters of the PGT which follow from light deflection and retardation experiments and composition-independent fifth-force data are obtained. It is shown that modern experimental data cannot rule out the existence of massive torsion particles with both large and very small masses.
Kawamura, Mari; Oohara, Ken-ichi; Nakamura, Takashi
2003-01-01
We are developing 3 dimensional simulation codes for coalescing binary neutron stars. A code using the maximal slicing condition is obtained. To evaluate the gravitational radiation, we implemented a gauge-invariant wave extraction and compared the wave forms with the metric tensors at the wave zone. The energy spectrum of the waves was also evaluated to investigate the possibility that the excitation of the quasi-normal modes of the black hole, which may be formed after the merger of two sta...
Gauge-invariant gravitational wave modes in pre-big bang cosmology
International Nuclear Information System (INIS)
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.)
Gauge theory and gravitation: an approach to a fiber bundle formalism
International Nuclear Information System (INIS)
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.)
Finite action, holographic conformal anomaly and quantum brane-worlds in D5 gauged supergravity
International Nuclear Information System (INIS)
We report our recent results concerning d5 gauged supergravity (dilatonic gravity) considered on AdS background. The finite action on such background as well as d4 holographic conformal anomaly (via AdS/CFT correspondence) are found. In such formalism the bulk potential is kept to be arbitrary, dilaton dependent function. Holographic RG in such theory is briefly discussed. d5 AdS brane-world Universe induce by quantum effects of brane CFT is constructed. Such brane is spherical, hyperbolic or flat one. Hence, the possibility of quantum creation of inflationary brane-world Universe is shown. (author)
Finite action, holographic conformal anomaly and quantum brane-worlds in d5 gauged supergravity
Nojiri, S.; Obregon, O.; Odintsov, S. D.; Ogushi, S.
2000-01-01
We report our recent results concerning d5 gauged supergravity (dilatonic gravity) considered on AdS background. The finite action on such background as well as d4 holographic conformal anomaly (via AdS/CFT correspondence) are found. In such formalism the bulk potential is kept to be arbitrary, dilaton dependent function. Holographic RG in such theory is briefly discussed. d5 AdS brane-world Universe induced by quantum effects of brane CFT is constructed. Such brane is spherical, hyperbolic o...
Hawking radiation from the Schwarzschild black hole with a global monopole via gravitational anomaly
International Nuclear Information System (INIS)
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
Gauge unification of basic forces particularly of gravitation with strong interactions
International Nuclear Information System (INIS)
Corresponding to the two known types of gauge theories, Yang-Mills with spin-one mediating particles and Einstein Weyl with spin-two mediating particles, it is speculated that two distinct gauge unifications of the basic forces appear to be taking place. One is the familiar Yang-Mills unification of weak and electromagnetic forces with the strong. The second is the less familiar gauge unification of gravitation with spin-two tensor-dominated aspects of strong interactions. It is proposed that there are strongly interacting spin-two strong gravitons obeying Einstein's equations, and their existence gives a clue to an understanding of the (partial) confinement of quarks, as well as of the concept of hadronic temperature, through the use of Schwarzschild de-Sitter-like partially confining solitonic solutions of the strong gravity Einstein equation
Gravitational and gauge couplings in Chern-Simons fractional spin gravity
Boulanger, Nicolas; Sundell, Per; Valenzuela, Mauricio
2016-01-01
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. We provide a necessary and sufficient condition for the consistency of the supertrace, through the existence of a certain ground state projector. We build this projector and check its properties to the first two orders in the number operator and to all orders in the deformation parameter. We then find the relation between the gravitational and internal gauge couplings in the resulting unified three-dimensional Chern-Simons theory for Blencowe-Vasiliev higher spin gravity coupled to fractional spin fields and internal gauge potentials. We also examine the model for integer or half-integer fractional spins, where infinite dimensional ideals arise and decouple, leaving finite dimensional gauge algebras gl(2 ℓ + 1) or gl( ℓ| ℓ + 1) and various real forms thereof.
Global anomalies in six dimensions
International Nuclear Information System (INIS)
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...
Gravitational energy for GR and Poincar 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 Poincar 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 Poincar transformations. They are best described in a local Poincar 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.
International Nuclear Information System (INIS)
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
International Nuclear Information System (INIS)
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.)
Dietrich, Tim; Bernuzzi, Sebastiano
2015-02-01
We reexamine the gravitational collapse of rotating neutron stars to black holes by new 3 +1 numerical relativity simulations employing the Z4c formulation of Einstein equations, the moving puncture gauge conditions, and a conservative mesh refinement scheme for the general relativistic hydrodynamics. The end state of the collapse is compared to the vacuum spacetime resulting from the evolution of spinning puncture initial data. Using a local analysis for the metric fields, we demonstrate that the two spacetimes actually agree. Gravitational waveforms are analyzed in some detail. We connect the emission of radiation to the collapse dynamics using simplified spacetime diagrams, and discuss the similarity of the waveform structure with the one of black hole perturbation theory.
Dietrich, Tim
2014-01-01
We reexamine the gravitational collapse of rotating neutron stars to black holes by new 3+1 numerical relativity simulations employing the Z4c formulation of Einstein equations, the moving puncture gauge conditions, and a conservative mesh refinement scheme or the general relativistic hydrodynamics. The end state of the collapse is compared to the vacuum spacetime resulting from the evolution of spinning puncture initial data. Using a local analysis for the metric fields, we demonstrate that the two spacetimes atually agree. Gravitational waveforms are analyzed in some detail. We connect the emission of radiation to the collapse dynamics using simplified spacetime diagrams, and discuss the similarity of the waveform structure with the one of black hole perturbation theory.
International Nuclear Information System (INIS)
Full text: (author)The intimate relation between Killing-Yano tensors and non-standard supersymmetries is pointed out. The gravitational anomalies are absent if the hidden symmetry is associated to a Killing-Yano tensor. In the Dirac theory on curved spaces, Killing-Yano tensors generate Dirac type operators involved in interesting algebraic structures as dynamical algebras or even infinite dimensional algebras or superalgebras. The general results are applied to the 4-dimensional Euclidean Taub-NUT space. One presents the infinite dimensional superalgebra of Dirac type operators on Taub-NUT space that can be seen as a twisted loop algebra
International Nuclear Information System (INIS)
Identification of the diagrams that can lead to gauge anomalies in the (minimal) Lorentz- and CPT-violating extension of quantum electrodynamics reveal these to be the electron self-energy and vertex correction (related to the Ward–Takahashi identity), the photon self-energy (related to the vacuum polarization tensor transversality) and the three-photon vertex diagrams. All but the latter were explicitly verified to be free of anomalies to first order in loop expansion. Here we provide this remaining evaluation and verify the absence of anomalies in this process. (paper)
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...
Anomalies, cohomology and generalized secondary classes
International Nuclear Information System (INIS)
The authors introduce, in this paper, their recent works on the generalized secondary characteristic classes, the cohomologies of gauge groups realized upon these classes and the degenerate forms of these classes, as well as their applications to the analyses on both gauge and gravitational anomalies in spacetimes of different dimensions. They also show the relations between their works and Faddeev's, Song's and Zumino's approaches
Hawking Radiation of Black Rings from Anomalies
Chen, Bin; Wei HE
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...
International Nuclear Information System (INIS)
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
International Nuclear Information System (INIS)
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,…
Jezierski, Jacek
1998-01-01
It is shown that the axial and polar perturbations of the spherically symmetric black hole can be described in a gauge-invariant way. The reduced phase space describing gravitational waves outside of the horizon is described by the gauge-invariant quantities. Both degrees of freedom fulfill generalized scalar wave equation. For the axial degree of freedom the radial part of the equation corresponds to the Regge-Wheeler result (Phys. Rev. 108, 1063-1069 (1957)) and for the polar one we get Zer...
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.
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).
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...
Does the Neptunian system of satellites challenge a gravitational origin for the Pioneer anomaly?
Iorio, Lorenzo
2009-01-01
If the Pioneer Anomaly was a genuine dynamical effect of gravitational origin, it should also affect the orbital motions of the solar system's bodies moving in the space regions in which the PA manifested itself in its presently known form, i.e. as a constant and uniform acceleration approximately directed towards the Sun with a non-zero magnitude (8.74+/-1.33) x 10^-10 m s^-2 after 20 au from the Sun. We preliminarily investigate its effects on the orbital motions of the Neptunian satellites Triton, Nereid and Proteus, located at about 30 au from the Sun, both analytically and numerically. The analytical calculations show that the PA-induced radial and transverse perturbations of Triton are of the order of a few km yr^-1, those of Nereid are about 10+/-100 km yr^-1, while Proteus experiences radial and transverse shifts of the order of 0.1 km yr^-1. The out-of-plane perturbations are negligible, apart from that of Nereid which amounts to about 20 km yr^-1. The corresponding orbital uncertainties obtained fro...
International Nuclear Information System (INIS)
We extend a previous analysis on the derivation of the dilaton WessZumino (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 ofthe 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 energymomentum tensors, 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)
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It is shown that on curved backgrounds, the Coulomb gauge Faddeev-Popov operator can have zero modes even in the Abelian case. These zero modes cannot be eliminated by restricting the path integral over a certain region in the space of gauge potentials. The conditions for the existence of these zero modes are studied for static spherically symmetric spacetimes in arbitrary dimensions. For this class of metrics, the general analytic expression of the metric components in terms of the zero modes is constructed. Such expression allows one to find the asymptotic behavior of background metrics, which induce zero modes in the Coulomb gauge, an interesting example being the three-dimensional anti-de Sitter spacetime. Some of the implications for quantum field theory on curved spacetimes are discussed.
Gauge theories, time-dependence of the gravitational constant and antigravity in the early universe
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It is shown that the interaction of the gravitational field with matter leads to a strong modification of the effective gravitational constant in the early universe. In certain cases this leads even to the change of sign of the gravitational constant, i.e. to antigravity in the early universe. (orig.)
Hawking radiation from the dilaton—(anti) de Sitter black hole via covariant anomaly
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Adopting the anomaly cancellation method, initiated by Robinson and Wilczek recently, this paper discusses Hawking radiation from the dilaton—(anti) de Sitter black hole. To save the underlying gauge and general covariance, it introduces covariant fluxes of gauge and energy-momentum tensor to cancel the gauge and gravitational anomalies. The result shows that the introduced compensating fluxes are equivalent to those of a 2-dimensional blackbody radiation at Hawking temperature with appropriate chemical potential. (general)
BRS cohomology and topological anomalies
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The occurrence of non-abelian anomalies in gauge theories and gravitation, first discovered via perturbative techniques, is now completely explained from the mathematical point of view by means of the family index theorem of Atiyah and Singer. Here we make contact between this approach and BRS cohomology, by showing that they yield the same non-abelian anomalies, provided a certain restriction to ''local'' functionals is not introduced from the very beginning. In particular, this solves the ''unicity'' problem for this kind of anomalies. Local BRS cohomology is still relevant for the abelian case. (orig.)
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
International Nuclear Information System (INIS)
We present new exact spherically symmetric solutions of the Wu-Yang-t'Hooft monopole and Julia-Zee dyon type of the SO(3)-Yang-Mills-(Higgs-)fields coupled to gravitation through a particular quadratic Poincare gauge field theory. The space-time metrics are of the Reissner-Nordstroem, DeSitter, and AntiDeSitter form with non-vanishing torsion always being present. Due to a free function occurring, the solutions given admit arbitrary vector torsion. We conclude that the local Cauchy-Kowalevski problem is not well posed even in the limit of vanishing Yang-Mills and Higgs fields. (author)
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
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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)
AdS solutions in gauge supergravities and the global anomaly for the product of complex two-cycles
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Cohomological methods are applied for the special set of solutions corresponding to rotating branes in arbitrary dimensions, AdS black holes (which can be embedded in ten or eleven dimensions), and gauge supergravities. A new class of solutions is proposed, the Hilbert modular varieties, which consist of the 2n-fold product of the two-spaces Hn /Γ (where Hn denotes the product of n upper half-planes, H 2, equipped with the co-compact action of Γ is contained in SL(2, R)n) and (H n)*/Γ (where (H 2)*=H 2Γ and Γ is a congruence subgroup of SL(2, R) n). The cohomology groups of the Hilbert variety, which inherit a Hodge structure (in the sense of Deligne), are analyzed, as well as bifiltered sequences, weight and Hodge filtrations, and it is argued that the torsion part of the cuspidal cohomology is involved in the global anomaly condition. Indeed, in the presence of the cuspidal part, all cohomology classes can be mapped to the boundary of the space and the cuspidal contribution can be involved in the global anomaly condition. (orig.)
Hawking radiation from Kerr–Newman de Sitter black hole via anomalies
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In this paper, Hawking radiation from the Kerr–Newman de Sitter black hole is studied via gauge anomaly and gravitational anomaly. The obtained results of Hawking radiation from the event horizon and the cosmological horizon accord with those by other methods. (general)
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...
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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.
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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
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...
An anomaly-free model in six dimensions
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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)
Renormalizable Quantum Gauge General Relativity
Wu, N
2003-01-01
The quantum gauge general relativity is proposed in the framework of quantum gauge theory of gravity. It is formulated based on gauge principle which states that the correct symmetry for gravitational interactions should be gravitational gauge symmetry. The gravitational gauge group is studied in the paper. Then gravitational gauge interactions of pure gravitational gauge field is studied. It is found that the field equation of gravitational gauge field is just the Einstein's field equation. After that, the gravitational interactions of scalar field, Dirac field and vector fields are studied, and unifications of fundamental interactions are discussed. Path integral quantization of the theory is studied in the paper. The quantum gauge general relativity discussed in this paper is a perturbatively renormalizable quantum gravity, which is one of the most important advantage of the quantum gauge general relativity proposed in this paper. A strict proof on the renormalizability of the theory is also given in this ...
Sanabria, Andres
The motion of a particle in the Kepler problem is characterized by a single frequency, the Kepler frequency. This means that in spherical coordinates radial, azimuthal and polar angles all have the same frequency and there is no precession. Einstein showed that in General Relativity, for the Schwarzschild metric, this degeneracy is broken and the radial and azimuthal frequencies become distinct. We will show how in the Kerr space-time the third frequency also gets a separate value. We will derive analytic expressions for all the frequencies. These frequencies can be written fully in terms of the canonical elliptic functions and the constants of the motion. We study some limiting examples, namely far away, or keplerian approximation, and the low eccentricity case. And we also extend our results to non-bound null geodesics, finding an exact result for the angle of deflection for equatorial trajectories. We also discuss a completely different problem. It is well known that there are very massive compact objects in the Universe. Despite some inconsistencies it is assumed that some of them become what we know as Black Holes. According to Hawking and his colleagues Black Holes radiate like a blackbody with a certain temperature. This result has been derived in different ways, one of them, presented by Wilczek and his colleagues uses gravitational anomalies. But there exist alternatives to the Black Hole model. In one of them, the very massive objects become gravitational vacuum stars or Gravastars, bubbles of dark energy. Turning the argument of Wilczek on its head, we argue that it solves naturally some of the inconsistencies.
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," Universit 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.
Interpretation of a short-term anomaly in the gravitational microlensing event MOA-2012-BLG-486
International Nuclear Information System (INIS)
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
Wyithe, S; Wyithe, Stuart; Loeb, Abraham
2002-01-01
Intensive monitoring campaigns have recently attempted to measure the time delays between multiple images of gravitational lenses. Some of the resulting light-curves show puzzling low-level, rapid variability which is unique to individual images, superimposed on top of (and concurrent with) longer time-scale intrinsic quasar variations which repeat in all images. We demonstrate that both the amplitude and variability time-scale of the rapid light-curve anomalies, as well as the correlation observed between intrinsic and microlensed variability, are naturally explained by stellar microlensing of a smooth accretion disk which is occulted by optically-thick broad-line clouds. The rapid time-scale is caused by the high velocities of the clouds (~5x10^3 km/s), and the low amplitude results from the large number of clouds covering the magnified or demagnified parts of the disk. The observed amplitudes of variations in specific lenses implies that the number of broad-line clouds that cover ~10% of the quasar sky is ...
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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
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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. © 2015 Royal Meteorological Society.
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 ?
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; Bhm, R; Bosnar, D; Correa, L; Debenjak, L; Denig, A; Distler, M O; Esser, A; Fonvieille, H; Fri?i?, I; de la Paz, M Gmez Rodrguez; Hoek, M; Kegel, S; Kohl, Y; Middleton, D G; Mihovilovi?, M; Mller, U; Nungesser, L; Pochodzalla, J; Rohrbeck, M; Ron, G; Majos, S Snchez; Schlimme, B S; Schoth, M; Schulz, F; Sfienti, C; irca, 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.
Anomalies in M-theory on singular G2-manifolds
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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)
One-loop effective actions and 2D hydrodynamics with anomalies
Ng, Gim Seng
2014-01-01
We revisit the study of a 2D quantum field theory in the hydrodynamic regime and develop a formalism based on Euclidean one-loop partition functions that is suitable to analyze transport properties due to gauge and gravitational anomalies. To do so, we generalize the method of a modified Dirac operator developed for zero-temperature anomalies to finite temperature, chemical potentials and rotations.
One-loop effective actions and 2D hydrodynamics with anomalies
Ng, Gim Seng; Surówka, Piotr
2015-06-01
We revisit the study of a 2D quantum field theory in the hydrodynamic regime and develop a formalism based on Euclidean one-loop partition functions that is suitable to analyze transport properties due to gauge and gravitational anomalies. To do so, we generalize the method of a modified Dirac operator developed for zero-temperature anomalies to finite temperature, chemical potentials and rotations.
One-loop effective actions and 2D hydrodynamics with anomalies
International Nuclear Information System (INIS)
We revisit the study of a 2D quantum field theory in the hydrodynamic regime and develop a formalism based on Euclidean one-loop partition functions that is suitable to analyze transport properties due to gauge and gravitational anomalies. To do so, we generalize the method of a modified Dirac operator developed for zero-temperature anomalies to finite temperature, chemical potentials and rotations
Gravitational interaction of fermion antisymmetric tensor fields
International Nuclear Information System (INIS)
The coupling is investigated of classical and quantum antisymmetric tensor fields describing fermions with the gauge gravitational field. It is shown that within the framework of the classical Einstein-Cartan theory the new generalized nonlinear fermion theory can be formulated, which turns out to be the correct microscopic description of the Weyssenhoff spinning fluid. The one-loop gravitational counterterms and the conformal stress tensor and the axial vector current anomalies are obtained. The differences between the antisymmetric tensor fermions and the usual Dirac spinor fields are discussed. (author)
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.)
Gravitational cubic interactions for a simple mixed-symmetry gauge field in AdS and flat backgrounds
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Boulanger, Nicolas [Service de Mecanique et Gravitation, Universite de Mons-UMONS, 20 Place du Parc, 7000 Mons (Belgium); Skvortsov, E D [P. N. Lebedev Physical Institute, Leninsky Prospect 53, 119991 Moscow (Russian Federation); Zinoviev, Yu M, E-mail: nicolas.boulanger@umons.ac.be, E-mail: skvortsov@lpi.ru, E-mail: Yurii.Zinoviev@ihep.ru [Institute for High Energy Physics Protvino, Moscow Region 142280 (Russian Federation)
2011-10-14
Cubic interactions between the simplest mixed-symmetry gauge field and gravity are constructed in anti-de Sitter (AdS) and flat backgrounds. Non-Abelian cubic interactions are obtained in AdS following various perturbative methods including the Fradkin-Vasiliev construction, with and without Stueckelberg fields. The action that features the maximal number of Stueckelberg fields can be considered in the flat limit without loss of physical degrees of freedom. The resulting interactions in flat space are compared with a classification of vertices obtained via the antifield cohomological perturbative method. It is shown that the gauge algebra becomes Abelian in the flat limit, in contrast to what happens for totally symmetric gauge fields in AdS. (paper)
Geometrical formulation of gauge theories
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We review some basic aspects of the geometry of gauge theories. Particularly, we introduce the concepts gauge potential, field intensity, matter field, gauge groups and symmetry of a physical configuration and we discuss the spontaneous symmetry breaking and the gauge theories of gravitation. 26 refs
Mickelsson, J
1996-01-01
A calculation of the chiral anomaly on a finite lattice without fermion doubling is presented . The lattice gauge field is defined in the spirit of noncommutative geometry. Standard formulas for the continuum anomaly are obtained as a limit.
Making sense of anomalous gauge theories
International Nuclear Information System (INIS)
An anomalous gauge theory is defined here as a gauge theory in which the field equation is inconsistent and gauge invariance is lost. A conventional approach to anomalous gauge theories, that of adjusting the fermion content so the anomaly vanishes, is discussed, followed by a mathematically coherent frame for anomalies. 10 refs
Current commutator anomalies and chiral anomalies in the canonical formalism
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Without recourse to the Bjorken-Johnson-Low (BJL) method, current-current and current-electric-field commutator anomalies are evaluated in chiral gauge theories in two- and four-dimensional spacetime with the help of a gauge covariant regularization method. The results are consistent with previous analyses through the BJL method, and partially confirmed Faddeev's conjecture on the commutator anomalies of the Gauss law constraint operators within the canonical formalism. The chiral anomalies of the current divergence are derived from these commutator anomalies in the Weyl gauge where current-electric-field commutator anomalies play important roles
On the simple evaluation of chiral anomalies in the path integral approach
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We comment on the relation between the Schwinger's proper time method and the one-dimensional supersymmetric path integral method in the evaluation of chiral anomalies in gauge and gravitational interactions. For this purpose, we introduce a modified one-dimensional path integral which is directly related to the proper time method by a Legendre transformation. This modified scheme provides a simple way of evaluating chiral anomalies. The one-dimensional path integral method is also shown to work for the trace anomaly in 4-dimensional flat space-time. (author)
International Nuclear Information System (INIS)
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)
Unification of Electromagnetic Interactions and Gravitational Interactions
Wu, Ning
2002-01-01
Unified theory of gravitational interactions and electromagnetic interactions is discussed in this paper. Based on gauge principle, electromagnetic interactions and gravitational interactions are formulated in the same manner and are unified in a semi-direct product group of U(1) Abel gauge group and gravitational gauge group.
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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.)
Mielke, E W
2006-01-01
Anomalies in Yang-Mills type gauge theories of gravity are reviewed. Particular attention is paid to the relation between the Dirac spin, the axial current j_5 and the non-covariant gauge spin C. Using diagrammatic techniques, we show that only generalizations of the U(1)- Pontrjagin four--form F^ F= dC arise in the chiral anomaly, even when coupled to gravity. Implications for Ashtekar's canonical approach to quantum gravity are discussed.
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Anomalies in Yang-Mills type gauge theories of gravity are reviewed. Particular attention is paid to the relation between the Dirac spin, the axial current j5 and the non-covariant gauge spin C. Using diagrammatic techniques, we show that only generalizations of the U(1)- Pontrjagin four-form F and F = dC arise in the chiral anomaly, even when coupled to gravity. Implications for Ashtekar's canonical approach to quantum gravity are discussed
The conformal anomaly and the neutral currents sector of the Standard Model
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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 (VV'). 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. As in the previous cases of QED and QCD, we find that the conformal anomaly induces an effective massless scalar interaction between gravity and the neutral currents in each gauge invariant component of the vertex. This is described by the exchange of an anomaly pole. We show that for a spontaneously broken theory the anomaly can be entirely attributed to the poles only for a conformally coupled Higgs scalar. In the exchange of a graviton, the trace part of the corresponding interaction can be interpreted as due to an effective dilaton, using a local version of the effective action. We discuss the implications of the anomalous Ward identity for the TVV' correlator for the structure of the gauge/gauge/effective dilaton vertex in the effective action. The analogy between these effective interactions and those related to the radion in theories with large extra dimensions is pointed out.
Wardell, Barry
2015-01-01
With a view to developing a formalism that will be applicable at second perturbative order, we devise a new practical scheme for computing the gravitational self-force experienced by a point mass moving in a curved background spacetime. Our method works in the frequency domain and employs the effective-source approach, in which a distributional source for the retarded metric perturbation is replaced with an effective source for a certain regularized self-field. A key ingredient of the calculation is the analytic determination of an appropriate puncture field from which the effective source and regularized residual field can be calculated. In addition to its application in our effective-source method, we also show how this puncture field can be used to derive tensor-harmonic mode-sum regularization parameters that improve the efficiency of the traditional mode-sum procedure. To demonstrate the method, we calculate the first-order-in-the-mass-ratio self-force and redshift invariant for a point mass on a circula...
Wardell, Barry; Warburton, Niels
2015-10-01
With a view to developing a formalism that will be applicable at second perturbative order, we devise a new practical scheme for computing the gravitational self-force experienced by a point mass moving in a curved background spacetime. Our method works in the frequency domain and employs the effective-source approach, in which a distributional source for the retarded metric perturbation is replaced with an effective source for a certain regularized self-field. A key ingredient of the calculation is the analytic determination of an appropriate puncture field from which the effective source and regularized residual field can be calculated. In addition to its application in our effective-source method, we also show how this puncture field can be used to derive tensor-harmonic mode-sum regularization parameters that improve the efficiency of the traditional mode-sum procedure. To demonstrate the method, we calculate the first-order-in-the-mass-ratio self-force and redshift invariant for a point mass on a circular orbit in Schwarzschild spacetime.
Cohomology and Topological Anomalies
Ekstrand, C
2001-01-01
The chiral anomaly can be considered as an object defined either on the space of gauge potentials or on the orbit space. We will discuss the relation between the two descriptions. We will also relate to the cohomology of the group of gauge transformations.
Cohomology and Topological Anomalies
Ekstrand, Christian
2000-01-01
The chiral anomaly can be considered as an object defined either on the space of gauge potentials or on the orbit space. We will discuss the relation between the two descriptions. We will also relate to the cohomology of the group of gauge transformations.
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This paper concentrates on the zig-zag equations and double complexes of the generalized secondary characteristic polynomials of Chern-Simons type, of the R-polynomials that cover both covariant and consistent anomalies. We propose a gauge group cohomology in which both covariant and consistent anomalies are 1-cocycles
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...
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.
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.
Analogue of the Witten effect in the Poincare gauge theory of gravity
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The gravitational contribution to the chiral anomaly is analysed in the framework of the Poincare gauge theory. It is shown that an additional CP-violating term 8*RR in the effective Lagrangian is equivalent to a shift in the mass of the Taub-NUT metric as felt by fermions. This analogue of the Witten effect is discussed in conjunction with the appearance of torsion in recently found exact solutions. (author)
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
What's wrong with anomalous chiral gauge theory?
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It is argued on general ground and demonstrated in the particular example of the Chiral Schwinger Model that there is nothing wrong with apparently anomalous chiral gauge theory. If quantised correctly, there should be no gauge anomaly and chiral gauge theory should be renormalisable and unitary, even in higher dimensions and with non-Abelian gauge groups. Furthermore, it is claimed that mass terms for gauge bosons and chiral fermions can be generated without spoiling the gauge invariance. 19 refs
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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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
More Anomalies from Fractional Branes
Bertolini, M; Frau, M; Lerda, A; Marotta, R
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
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.
Hamiltonian interpretation of anomalies
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A family of quantum systems parameterized by the points of a compact space can realize its classical symmetries via a new kind of nontrivial ray representation. We show that this phenomenon in fact occurs for the quantum mechanics of fermions in the presence of background gauge fields, and is responsible for both the nonabelian anomaly and Witten's SU(2) anomaly. This provides a hamiltonian interpretation of anomalies: in the affected theories Gauss' law cannot be implemented. The analysis clearly shows why there are no further obstructions corresponding to higher spheres in configuration space, in agreement with a recent result of Atiyah and Singer. (orig.)
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.
Ward identities and gauge independence in general chiral gauge theories
Anselmi, Damiano
2015-01-01
Using the Batalin-Vilkovisky formalism, we study the Ward identities and the equations of gauge dependence in potentially anomalous general gauge theories, renormalizable or not. A crucial new term, absent in manifestly nonanomalous theories, is responsible for interesting effects. We prove that gauge invariance always implies gauge independence, which in turn ensures perturbative unitarity. Precisely, we consider potentially anomalous theories that are actually free of gauge anomalies thanks to the Adler-Bardeen theorem. We show that when we make a canonical transformation on the tree-level action, it is always possible to re-renormalize the divergences and re-fine-tune the finite local counterterms, so that the renormalized $\\Gamma $ functional of the transformed theory is also free of gauge anomalies, and is related to the renormalized $\\Gamma $ functional of the starting theory by a canonical transformation. An unexpected consequence of our results is that the beta functions of the couplings may depend on...
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...
Invariant Regularization of Supersymmetric Chiral Gauge Theory
Hayashi, Takuya; Ohshima, Yoshihisa; Okuyama, Kiyoshi; Suzuki, Hiroshi
1998-01-01
We formulate a manifestly supersymmetric gauge covariant regularization of supersymmetric chiral gauge theories. In our scheme, the effective action in the superfield background field method above one-loop is always supersymmetric and gauge invariant. The gauge anomaly has a covariant form and can emerge only in one-loop diagrams with all the external lines being the background gauge superfield. We also present several illustrative applications in the one-loop approximation: the self-energy p...
Relativistic rigid particles: classical tachyons and quantum anomalies
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Causal rigid particles whose action includes an arbitrary dependence on the world-line extrinsic curvature are considered. General classes of solutions are constructed, including causal tachyonic ones. The Hamiltonian formulation is developed in detail except for one degenerate situation for which only partial results are given and requiring a separate analysis. However, for otherwise generic rigid particles, the precise specification of Hamiltonian gauge symmetries is obained with in particular the identification of the Teichmueller and modular spaces for these systems. Finally, canonical quantisation of the generic case is performed paying special attention to the phase space restriction due to causal propagation. A mixed Lorenz-gravitational anomaly is found in the commutator of Lorentz boosts with world-line reparametrisations. The subspace of gauge invariant physical states is therefore not invariant under Lorentz transformations. Consequences for rigid strings and membranes are also discussed. (orig.)
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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.)
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.
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).
Theory of gravitational interactions
Gasperini, Maurizio
2013-01-01
This reference textbook is an up-to-date and self-contained introduction to the theory of gravitational interactions. The first part of the book follows the traditional presentation of general relativity as a geometric theory of the macroscopic gravitational field. A second, advanced part then discusses the deep analogies (and differences) between a geometric theory of gravity and the gauge theories of the other fundamental interactions. This fills a gap which is present in the context of the traditional approach to general relativity, and which usually makes students puzzled about the role of gravity. The necessary notions of differential geometry are reduced to the minimum, leaving more room for those aspects of gravitational physics of current phenomenological and theoretical interest, such as the properties of gravitational waves, the gravitational interactions of spinors, and the supersymmetric and higher-dimensional generalization of the Einstein equations. Theory of Gravitational Interactions will be o...
Path Integrals and Anomalies in Curved Space
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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)
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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
Anomaly poles as common signatures of chiral and conformal anomalies
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One feature of the chiral anomaly, analyzed in a perturbative framework, is the appearance of massless poles which account for it. They are identified by a spectral analysis of the anomaly graph and are usually interpreted as being of an infrared origin. Recent investigations show that their presence is not just confined in the infrared, but that they appear in the effective action under the most general kinematical conditions, even if they decouple in the infrared. Further studies reveal that they are responsible for the non-unitary behaviour of these theories in the ultraviolet (UV) region. We extend this analysis to the case of the conformal anomaly, showing that the effective action describing the interaction of gauge fields with gravity is characterized by anomaly poles that give the entire anomaly and are decoupled in the infrared (IR), in complete analogy with the chiral case. This complements a related analysis by Giannotti and Mottola on the trace anomaly in gravity, in which an anomaly pole has been identified in the corresponding correlator using dispersion theory in the IR. Our extension is based on an exact computation of the off-shell correlation function involving an energy-momentum tensor and two vector currents (the gauge-gauge-graviton vertex) which is responsible for the appearance of the anomaly.
Symplectic gauge fields and dark matter
Asorey, J.; Asorey, M.; 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...
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.
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.
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.
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.
Ward identities and gauge independence in general chiral gauge theories
Anselmi, Damiano
2015-07-01
Using the Batalin-Vilkovisky formalism, we study the Ward identities and the equations of gauge dependence in potentially anomalous general gauge theories, renormalizable or not. A crucial new term, absent in manifestly nonanomalous theories, is responsible for interesting effects. We prove that gauge invariance always implies gauge independence, which in turn ensures perturbative unitarity. Precisely, we consider potentially anomalous theories that are actually free of gauge anomalies thanks to the Adler-Bardeen theorem. We show that when we make a canonical transformation on the tree-level action, it is always possible to re-renormalize the divergences and re-fine-tune the finite local counterterms, so that the renormalized Γ functional of the transformed theory is also free of gauge anomalies, and is related to the renormalized Γ functional of the starting theory by a canonical transformation. An unexpected consequence of our results is that the beta functions of the couplings may depend on the gauge-fixing parameters, although the physical quantities remain gauge independent. We discuss nontrivial checks of high-order calculations based on gauge independence and determine how powerful they are.
To theory of gravitational interaction
Minkevich, A. V.
2008-01-01
Some principal problems of general relativity theory and attempts of their solution are discussed. The Poincare gauge theory of gravity as natural generalization of Einsteinian gravitation theory is considered. The changes of gravitational interaction in the frame of this theory leading to the solution of principal problems of general relativity theory are analyzed.
The aetiology of sigma model anomalies
International Nuclear Information System (INIS)
Certain nonlinear sigma models with fermions are ill-defined due to an anomaly which exhibits characteristics of both the nonabelian gauge theory anomaly and the SU(2) anomaly. The simplest way to diagnose the anomaly involves consideration of the global topology of the theory. We review the mathematical methods needed for this analysis and apply then to several supersymmetric sigma models. Some of these are found to be anomalous. (orig.)
Anomalies, Becchi-Rouet-Stora cohomology, and effective theories
International Nuclear Information System (INIS)
A survey is made of the known Becchi-Rouet-Stora (BRS) cohomology and potential anomalies in ''nonrenormalizable'' effective gauge theories with and without supersymmetry. The probable existence of higher-dimension Abelian anomalies is mentioned. Supersymmetric theories have complicated BRS cohomology, but at least for N=1 and D=4, it appears that this does not give rise to corresponding anomalies so long as the gauge anomalies are eliminated
Toward a gauge field theory of gravity.
Yilmaz, H.
Joint use of two differential identities (Bianchi and Freud) permits a gauge field theory of gravity in which the gravitational energy is localizable. The theory is compatible with quantum mechanics and is experimentally viable.
The "Parity" Anomaly On An Unorientable Manifold
Witten, Edward
2016-01-01
The "parity" anomaly -- more accurately described as an anomaly in time-reversal or reflection symmetry -- arises in certain theories of fermions coupled to gauge fields and/or gravity in a spacetime of odd dimension. The "parity" anomaly has traditionally been studied on orientable manifolds only, but recent developments involving topological superconductors have made it clear that one can get more information by asking what happens on an unorientable manifold. In this paper, we analyze the "parity" anomaly for fermions coupled to gauge fields and gravity in $2+1$ dimensions. We consider applications to gapped boundary states of a topological superconductor and to M2-branes in string/M-theory.
Discrete R symmetries and anomalies
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We comment on aspects of discrete anomaly conditions focussing particularly on R symmetries. We review the Green-Schwarz cancellation of discrete anomalies, providing a heuristic explanation why, in the heterotic string, only the “model-independent dilaton” transforms non-linearly under discrete symmetries; this argument suggests that, in other theories, multiple fields might play a role in anomaly cancellations, further weakening any anomaly constraints at low energies. We provide examples in open string theories of non-universal discrete anomalies at low energies. We then consider the fact that R symmetries are necessarily broken at low energies. We exhibit dynamical models, in which fields charged under the Standard Model gauge group (for example, a doublet and a triplet) gain roughly equal masses, but where the doublet and the triplet possess different discrete charges and the low-energy anomaly conditions fail
Energy-Momentum and Gauge Conservation Laws
Giachetta, G.; Mangiarotti, L.; Sardanashvily, G.
1998-01-01
We treat energy-momentum conservation laws as particular gauge conservation laws when generators of gauge transformations are horizontal vector fields on fibre bundles. In particular, the generators of general covariant transformations are the canonical horizontal prolongations of vector fields on a world manifold. This is the case of the energy-momentum conservation laws in gravitation theories. We find that, in main gravitational models, the corresponding energy-momentum flows reduce to the...
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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
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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)
Anomaly Structure of Regularized Supergravity
Butter, Daniel; Gaillard, Mary K.
2015-01-01
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 Kähler moduli Ti 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 (PV) 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. The resulting chiral anomaly forms a supermultiplet with the corresponding conformal anomaly, provided the ultraviolet cutoff has the appropriate field dependence, in which case total derivative terms, such as Gauss-Bonnet, do not drop out from the effective action. The anomalies can be partially canceled by the four-dimensional version of the Green-Schwarz mechanism, but additional counterterms, and/or a more elaborate set of Pauli-Villars fields and couplings, are needed to cancel the full anomaly, including D -term contributions to the conformal anomaly that are nonlinear in the parameters of the anomalous transformations.
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 Bogus - Spacecraft anomalies due to the space environment range from minor operational problems to permanent spacecraft failure. The NGDC Spacecraft Anomaly...
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This invention relates to vacuum gauges, particularly of the type known as Penning gauges, which are cold cathode ionisation gauges, in which a magnetic field is used to lengthen the electron path and thereby increase the number of ions produced. (author)
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.
Anomalous transport due to scale anomaly
Chernodub, M N
2016-01-01
We show that the scale anomaly in field theories leads to new anomalous transport effects that emerge in external electromagnetic field in inhomogeneous gravitational background. In inflating geometry the QED scale anomaly generates electric current which flows in opposite direction with respect to background electric field. In static spatially inhomogeneous gravitational background the dissipationless electric current flows transversely both to the magnetic field axis and to the gradient of the inhomogeneity. The anomalous currents are proportional to the beta function of the theory.
Relevance of induced gauge interactions in decoherence
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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
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, however, is that th...
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 ...
Anomaly mediation from unbroken supergravity
D'Eramo, Francesco; Thaler, Jesse; Thomas, Zachary
2013-09-01
When supergravity (SUGRA) is spontaneously broken, it is well known that anomaly mediation generates sparticle soft masses proportional to the gravitino mass. Recently, we showed that one-loop anomaly-mediated gaugino masses should be associated with unbroken supersymmetry (SUSY). This counterintuitive result arises because the underlying symmetry structure of (broken) SUGRA in flat space is in fact (unbroken) SUSY in anti-de Sitter (AdS) space. When quantum corrections are regulated in a way that preserves SUGRA, the underlying AdS curvature (proportional to the gravitino mass) necessarily appears in the regulated action, yielding soft masses without corresponding goldstino couplings. In this paper, we extend our analysis of anomaly mediation to sfermion soft masses. Already at tree-level we encounter a number of surprises, including the fact that zero soft masses correspond to broken (AdS) SUSY. At one-loop, we explain how anomaly mediation appears when regulating SUGRA in a way that preserves super-Weyl invariance. We find that recent claims in the literature about the non-existence of anomaly mediation were based on a Wilsonian effective action with residual gauge dependence, and the gauge-invariant 1PI effective action contains the expected anomaly-mediated spectrum. Finally, we calculate the sfermion spectrum to all orders, and use supertrace relations to derive the familiar two-loop soft masses from minimal anomaly mediation, as well as unfamiliar tree-level and one-loop goldstino couplings consistent with renormalization group invariance.
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
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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.)
Chiral gauged fermions on a lattice
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The chiral fermion model with local multifermion interactions proposed in Nucl. Phys. B 486 (1997) 282 and Phys. Rev. D 61 (2000) 054502 processes an exact SUL(2) chiral gauge symmetry and SUL(2)xUR(1) chiral flavour symmetry on a lattice and a plausible scaling region for the target chiral gauge theory in the continuum limit. Following the previous analysis of massive and massless fermion spectra in the scaling region, we compute the one-particle-irreducible coupling vertices between gauge field and fermions by the strong multifermion coupling expansion and analytical continuation of these vertex functions in the momentum space. We show a peculiar scenario that a massless fermion is SUL(2)-chirally gauged in the low energy and 15 non-degenerate massive Dirac fermions are SUL(2)-vectorially gauged at the lattice scale O(1/a). The Ward identities associated to the chiral gauge symmetry are realized by both the massless chiral fermion and massive Dirac fermions. These Ward identities protect the perturbative calculations in the small gauge coupling from hard gauge-symmetry breakings and lead to the normal gauge-invariant renormalization prescription. The vacuum functional is perturbatively computed by a continuum regularization scheme in 16 edges of Brillouin zones. We achieve the correct form of the gauge anomaly and UL(1) fermion-flavour singlet anomaly with the soft chiral symmetry breaking scale that is much smaller than the lattice scale. The residual breakings of chiral gauge symmetry after the gauge anomaly cancellation are eliminated in the normal gauge-invariant renormalization prescription. We discuss the consistency of the scenario and the reasons for it to work for perturbative and non-perturbative gauge field
Low-scale gauge mediation with a 100 TeV gravitino
Asano, Masaki; Nakai, Yuichiro; Yokozaki, Norimi
2016-03-01
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 the usual gauge mediation on the visible brane. Importantly, the Higgs Bμ-term vanishes at the leading order, which enables us to obtain the suitable μ -Bμ 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 case (2), the cosmological moduli problem may be relaxed as well.
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.
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)
These lectures contain developments of an integral formalism of non-quantized gauge fields. The concept of non-integrable phase factors is introduced and global considerations are discussed. A Gauge--Riemannian calculus and variational calculations are developed which are as convenient as the usual Riemannian calculus
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...
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 α by means of quaternion-gauge formalism and the corresponding field equations have also been derived in a unique and consistent way. (author)
Gauge and Einstein Gravity from Non-Abelian Gauge Models on Noncommutative Spaces
Vacaru, Sergiu I.
2000-01-01
Following the formalism of enveloping algebras and star product calculus we formulate and analyze a model of gauge gravity on noncommutative spaces and examine the conditions of its equivalence to general relativity. The corresponding Seiberg-Witten maps are established which allow the definition of respective dynamics for a finite number of gravitational gauge field components on noncommutative spaces.
Chiral supergravity and anomalies
Mielke, E W; Macias, Alfredo; Mielke, Eckehard W.
1999-01-01
Similarily as in the Ashtekar approach, the translational Chern-Simons term is, as a generating function, instrumental for a chiral reformulation of simple (N=1) supergravity. After applying the algebraic Cartan relation between spin and torsion, the resulting canonical transformation induces not only decomposition of the gravitational fields into selfdual and antiselfdual modes, but also a splitting of the Rarita-Schwinger fields into their chiral parts in a natural way. In some detail, we also analyze the consequences for axial and chiral anomalies.
... genetic terms used on this page Learning About Poland Anomaly What is Poland anomaly? What are the ... Anomaly Additional Resources for Poland Anomaly What is Poland anomaly? Named after Sir Alfred Poland, Poland anomaly ( ...
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
Statistical Geometry of Gravitation
Bootello, Javier
2007-01-01
General Relativity explains with precision the anomalous advance of the perihelion of Mercury, discovered by Le Verrier in 1859. Otherwise, diverse post-Newtonian proposals trying to solve this anomaly, introduce mathematical potentials focused on a finite propagation speed. This paper tries to set some properties that should have any hypothetical gravitational potential suitable with material objects inside a physical universe. If a propagation speed is admitted, this assumption must link it...
Graviton as a pair of collinear gauge bosons
Stephan Stieberger; Taylor, Tomasz R.
2014-01-01
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 th...
The geometry and physics of Abelian gauge groups in F-theory
International Nuclear Information System (INIS)
In this thesis we study the geometry and the low-energy effective physics associated with Abelian gauge groups in F-theory compactifications. To construct suitable torus-fibered Calabi-Yau manifolds, we employ the framework of toric geometry. By identifying appropriate building blocks of Calabi-Yau manifolds that can be studied independently, we devise a method to engineer large numbers of manifolds that give rise to a specified gauge group and achieve a partial classification of toric gauge groups. Extending our analysis from gauge groups to matter spectra, we prove that the matter content of the most commonly studied F-theory set-ups is rather constrained. To circumvent such limitations, we introduce an algorithm to analyze torus-fibrations defined as complete intersections and present several novel kinds of F-theory compactifications. Finally, we show how torus-fibrations without section are linked to fibrations with multiple sections through a network of successive geometric transitions. In order to investigate the low-energy effective physics resulting from our compactifications, we apply M- to F-theory duality. After determining the effective action of F-theory with Abelian gauge groups in six dimensions, we compare the loop-corrected Chern-Simons terms to topological quantities of the compactification manifold to read off the massless matter content. Under certain assumptions, we show that all gravitational and mixed anomalies are automatically canceled in F-theory. Furthermore, we compute the low-energy effective action of F-theory compactifications without section and suggest that the absence of a section signals the presence of an additional massive Abelian gauge field. Adjusting our analysis to four dimensions, we show that remnants of this massive gauge field survive as discrete symmetries that impose selection rules on the Yukawa couplings of the effective theory.
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 σ-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.)
Diffeomorphism cohomology and gravitational anomalies: Pt. 1
International Nuclear Information System (INIS)
The Faddeev-Popov charge-zero and charge-one sectors of the cohomology space of the differential operator deltasub(GAMMAsub(c1))sup(L) which induces general co-ordinate transformations in four-dimensional space-time are studied. It will be used, with some modification, a technique introduced some years ago by Dixon. In this paper it is shown that the cohomology of the operator deltasub(GAMMAsub(c1))sup(L) on the local functional space is isomorphic to the cohomology of the operator S deltasub(GAMMAsub(c1))sup(L) - Csup(lambda)(x) deltasub(lambda) -deltasub(lambda)Csup(lambda)(x) on the domain of local polynomial functions
Massimo BianchiDipartimento di Fisica and INFN, Universita' di Roma ``Tor Vergata''; Morales, Jose F
2000-01-01
We show that massless RR tadpoles in vacuum configurations with open and unoriented strings are always related to anomalies. RR tadpoles arising from sectors of the internal SCFT with non-vanishing Witten index are in one-to-one correspondence with conventional irreducible anomalies. The anomalous content of the remaining RR tadpoles can be disclosed by considering anomalous amplitudes with higher numbers of external legs. We then provide an explicit parametrization of the a...
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 ...
Anomaly Poles as Common Signatures of Chiral and Conformal Anomalies
Armillis, Roberta; Rose, Luigi Delle
2009-01-01
One feature of the chiral anomaly, analyzed in a perturbative framework, is the appearance of massless poles which account for it. They are identified by a spectral analysis of the anomaly graph and are usually interpreted as being of an infrared origin. Recent investigations shown that their presence is not just confined in the infrared, but that they appear in the effective action under the most general kinematical conditions, even if they decouple in the infrared. Further studies reveal that they are responsible for the non-unitary behaviour of these theories in the ultraviolet (UV) region. We extend this analysis to the case of the conformal anomaly, showing that the effective action describing the interaction of gauge fields with gravity is characterized by anomaly poles that give the entire anomaly and are decoupled in the infrared (IR), in complete analogy with the chiral case. This complements a related analysis by Giannotti and Mottola on the trace anomaly in gravity, in which an anomaly pole has bee...
Anomalies of discrete symmetries in various dimensions and group cohomology
Kapustin, Anton
2014-01-01
We study 't Hooft anomalies for discrete global symmetries in bosonic theories in 2, 3 and 4 dimensions. We show that such anomalies may arise in gauge theories with topological terms in the action, if the total symmetry group is a nontrivial extension of the global symmetry by the gauge symmetry. Sometimes the 't Hooft anomaly for a d-dimensional theory with a global symmetry G can be canceled by anomaly inflow from a (d+1)-dimensional topological gauge theory with gauge group G. Such d-dimensional theories can live on the surfaces of Symmetry Protected Topological Phases. We also give examples of theories with more severe 't Hooft anomalies which cannot be canceled in this way.
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.
Galilean anomalies and their effect on hydrodynamics
Jain, Akash
2016-03-01
We study flavor 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 the relativistic case, we find that Galilean anomalies also survive only in even dimensions. Further, these anomalies only effect the flavor and rotational symmetries of a Galilean theory; in particular, the Milne boost symmetry remains nonanomalous. We also extend the transgression machinery used in relativistic fluids to Galilean fluids, and use it to determine how these anomalies affect the constitutive relations of a Galilean fluid. Unrelated to the Galilean fluids, we propose an analogue of the off-shell second law of thermodynamics for relativistic fluids, to include torsion and a conserved spin current in the vielbein formalism. Interestingly, we find that even in the absence of spin current and torsion the entropy currents in the two formalisms are different: while the usual entropy current gets a contribution from the gravitational anomaly, the entropy current in the vielbein formalism does not have any anomaly-induced part.
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)
An introduction to the unified gauge theories of weak and electromagnetic interactions is given. The ingredients of gauge theories and symmetries and conservation laws lead to discussion of local gauge invariance and QED, followed by weak interactions and quantum flavor dynamics. The construction of the standard SU(2)xU(1) model precedes discussion of the unification of weak and electromagnetic interactions and weak neutral current couplings in this model. Presentation of spontaneous symmetry breaking and spontaneous breaking of a local symmetry leads to a spontaneous breaking scheme for the standard SU(2)xU(1) model. Consideration of quarks, leptons, masses and the Cabibbo angles, of the four quark and six quark models and CP violation lead finally to grand unification, followed by discussion of mixing angles in the Georgi-Glashow model, the Higgses of the SU(5) model and proton/ neutron decay in SU(5). (JIW)
Anomaly mediation in local effective theories
International Nuclear Information System (INIS)
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
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.)
Composite gauge bosons of transmuted gauge symmetry
International Nuclear Information System (INIS)
It is shown that effective gauge theories of composite gauge bosons describing the dynamics of composite quarks and leptons can be transmuted from the subcolor gauge theory describing that of subquarks due to the condensation of subquarks and that the equality of effective gauge coupling constants can result as in a grand unified gauge theory. (author)
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.
Gravity: a gauge theory perspective
Nester, James M
2016-01-01
The evolution of a generally covariant theory is under-determined. One hundred years ago such dynamics had never before been considered; its ramifications were perplexing, its future important role for all the fundamental interactions under the name gauge principle could not be foreseen. We recount some history regarding Einstein, Hilbert, Klein and Noether and the novel features of gravitational energy that led to Noether's two theorems. Under-determined evolution is best revealed in the Hamiltonian formulation. We developed a covariant Hamiltonian formulation. The Hamiltonian boundary term gives covariant expressions for the quasi-local energy, momentum and angular momentum. Gravity can be considered as a gauge theory of the local Poincar\\'e group. The dynamical potentials of the Poincar\\'e gauge theory of gravity are the frame and the connection. The spacetime geometry has in general both curvature and torsion. Torsion naturally couples to spin; it could have a significant magnitude and yet not be noticed,...
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.)
Entanglement entropy and anomaly inflow
Hughes, Taylor L.; Leigh, Robert G.; Parrikar, Onkar; Ramamurthy, Srinidhi T.
2016-03-01
We study entanglement entropy for parity-violating (time-reversal breaking) quantum field theories on R1 ,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 nontrivial 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 entanglement spectrum. These results can be generally applied to 2 +1 -d topological phases of matter that have edge theories with gravitational anomalies, and provide a precise connection between the gravitational anomaly of the physical edge theory and the low-lying spectrum of the entanglement Hamiltonian.
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...
PENROSE, L.S.; SMITH, G.F.
BOTH CLINICAL AND PATHOLOGICAL ASPECTS AND MATHEMATICAL ELABORATIONS OF DOWN'S ANOMALY, KNOWN ALSO AS MONGOLISM, ARE PRESENTED IN THIS REFERENCE MANUAL FOR PROFESSIONAL PERSONNEL. INFORMATION PROVIDED CONCERNS (1) HISTORICAL STUDIES, (2) PHYSICAL SIGNS, (3) BONES AND MUSCLES, (4) MENTAL DEVELOPMENT, (5) DERMATOGLYPHS, (6) HEMATOLOGY, (7)…
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.
Target Spaces from Chiral Gauge Theories
Melnikov, Ilarion V; Sethi, Savdeep; Stern, Mark
2012-01-01
Chiral gauge theories in two dimensions with (0,2) supersymmetry are central in the study of string compactifications. Remarkably little is known about generic (0,2) theories. We consider theories with branches on which multiplets with a net gauge anomaly become massive. The simplest example is a relevant perturbation of the gauge theory that flows to the CP(n) model. To compute the effective action, we derive a useful set of Feynman rules for (0,2) supergraphs. From the effective action, we see that the infra-red geometry reflects the gauge anomaly by the presence of a boundary at finite distance. In generic examples, there are boundaries, fluxes and branes; the resulting spaces are non-Kahler.
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...
Weyl gauging and conformal invariance
International Nuclear Information System (INIS)
Scale-invariant actions in arbitrary dimensions are investigated in curved space to clarify the relation between scale, Weyl and conformal invariance on the classical level. The global Weyl group is gauged. Then the class of actions is determined for which Weyl gauging may be replaced by a suitable coupling to the curvature (Ricci gauging). It is shown that this class is exactly the class of actions which are conformally invariant in flat space. The procedure yields a simple algebraic criterion for conformal invariance and produces the improved energy-momentum tensor in conformally invariant theories in a systematic way. It also provides a simple and fundamental connection between Weyl anomalies and central extensions in two dimensions. In particular, the subset of scale-invariant Lagrangians for fields of arbitrary spin, in any dimension, which are conformally invariant is given. An example of a quadratic action for which scale invariance does not imply conformal invariance is constructed. (orig.)
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...
On an Interpretation of Non-Riemannian Gravitation
International Nuclear Information System (INIS)
Motivated by the invariance of actions under gauge symmetries the definitions of standard clocks in theories of gravitation are discussed. We argue that standard Einsteinian clocks can be defined in non-Riemannian theories of gravitation and that atomic clocks may be adopted to measure proper time in the presence of non-Riemannian gravitational fields. These ideas are illustrated in terms of a recently developed model of gravitation based on a non-Riemannian space-time geometry. (author)
Gauged WZW Models via Equivariant Cohomology
García-Compeán, Hugo; Paniagua, Pablo
The problem of finding a systematic computation of the gauge-invariant extension of WZW term by using equivariant cohomology is addressed. Witten's analysis for the two-dimensional case is extended to higher dimensions, in particular to four dimensions. It is shown that Cartan's model is used to find the anomaly cancellation condition while Weil's model is more appropriated to express the gauge-invariant extension of the WZW term. In the process we point out that both models are also useful to emphasize some nice relations with the Abelian anomaly.
S-matrix theory for gravitational field
International Nuclear Information System (INIS)
Major results of the investigation conducted on the quantum theory of the gravitational field and reported to the conference are summarized. The S matrix has been constructed in the most general class of gauges including relativistic ones. The causes of the failure to apply the proper-time regularization technique to gravitational interaction are considered. The corrected and improved proper-time method makes it possible to obtain the universal expression for one-loop divergences in and arbitrary system of gravitational fields. Under the assumption of mass-shell renormalizability the quantum theory of the gravitational field is asymptotically free
Probing gravitational dark matter
Ren, Jing; He, Hong-Jian
2015-03-01
So far all evidences of dark matter (DM) come from astrophysical and cosmological observations, due to the gravitational interactions of DM. It is possible that the true DM particle in the universe joins gravitational interactions only, but nothing else. Such a Gravitational DM (GDM) may act as a weakly interacting massive particle (WIMP), which is conceptually simple and attractive. In this work, we explore this direction by constructing the simplest scalar GDM particle χs. It is a Bbb Z2 odd singlet under the standard model (SM) gauge group, and naturally joins the unique dimension-4 interaction with Ricci curvature, ξsχs2Script R, where ξs is the dimensionless nonminimal coupling. We demonstrate that this gravitational interaction ξsχs2Script R, together with Higgs-curvature nonminimal coupling term ξhH†HScript R, induces effective couplings between χs2 and SM fields, and can account for the observed DM thermal relic abundance. We analyze the annihilation cross sections of GDM particles and derive the viable parameter space for realizing the DM thermal relic density. We further study the direct/indirect detections and the collider signatures of such a scalar GDM. These turn out to be highly predictive and testable.
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.
International Nuclear Information System (INIS)
A gauge supporting device for measuring say a square tube comprises a pair of rods or guides in tension between a pair of end members, the end members being spaced apart by a compression member or members. The tensioned guides provide planes of reference for measuring devices moved therealong on a carriage. The device is especially useful for making on site dimensional measurements of components, such as irradiated and therefore radioactive components, that cannot readily be transported to an inspection laboratory. (UK)
Improved Moving Puncture Gauge Conditions for Compact Binary Evolutions
Etienne, Zachariah B; 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 (BBH) 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, 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, yielding more cleanly convergent waveforms and $\\sim 40%$ lower waveform phase and amplitude errors during inspiral at typica...
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...
Statistical Geometry of Gravitation
Bootello, J
2007-01-01
General Relativity explains with precision the anomalous advance of the perihelion of Mercury, discovered by Le Verrier in 1859. Otherwise, diverse post-Newtonian proposals trying to solve this anomaly, introduce mathematical potentials focused on a finite propagation speed. This paper tries to set some properties that should have any hypothetical gravitational potential suitable with material objects inside a physical universe. If a propagation speed is admitted, this assumption must link its origin, the continuous update, the trajectory, the retarded action and impulse mechanism (transit action) in the final target. This gravitational potential, tries to explain the anomalous shift of the perihelion of Mercury. Otherwise, applied as a potential of force added to a mechanical momentum, could give a partial explanation of the anomalous acceleration of Pioneer 10/11. Anyway, it is an hypothetical conjecture without any proof of its physical reality
Transgression forms and extensions of Chern-Simons gauge theories
Mora, Pablo; Olea, Rodrigo; Troncoso, Ricardo(Centro de Estudios Científicos (CECs), Av. Arturo Prat 514, Valdivia, Chile); Zanelli, Jorge
2006-01-01
A gauge invariant action principle, based on the idea of transgression forms, is proposed. The action extends the Chern-Simons form by the addition of a boundary term that makes the action gauge invariant (and not just quasi-invariant). Interpreting the spacetime manifold as cobordant to another one, the duplication of gauge fields in spacetime is avoided. The advantages of this approach are particularly noticeable for the gravitation theory described by a Chern-Simons lagrangian for the AdS ...
Connections between Schwinger terms and anomalies
International Nuclear Information System (INIS)
We present examples of a new type of Schwinger terms appearing in commutators of energy-momentum tensor. We demonstrate them in two-dimensional flat Minkowski space. The Schwinger terms which correspond to gravitational anomaly appear in different places from those of conformal anomaly. Nevertheless, they still preserve the Jacobi identity. We also discuss the relation between anomalies and the Schwinger terms. In any-dimensional curved space-time Faddeev's cohomological technique works well. Therefore we can derive the Schwinger terms in curved space-time. (author)
Characteristic classes of gauge systems
International Nuclear Information System (INIS)
We define and study invariants which can be uniformly constructed for any gauge system. By a gauge system we understand an (anti-)Poisson supermanifold provided with an odd Hamiltonian self-commuting vector field called a homological vector field. This definition encompasses all the cases usually included into the notion of a gauge theory in physics as well as some other similar (but different) structures like Lie or Courant algebroids. For Lagrangian gauge theories or Hamiltonian first class constrained systems, the homological vector field is identified with the classical BRST transformation operator. We define characteristic classes of a gauge system as universal cohomology classes of the homological vector field, which are uniformly constructed in terms of this vector field itself. Not striving to exhaustively classify all the characteristic classes in this work, we compute those invariants which are built up in terms of the first derivatives of the homological vector field. We also consider the cohomological operations in the space of all the characteristic classes. In particular, we show that the (anti-)Poisson bracket becomes trivial when applied to the space of all the characteristic classes, instead the latter space can be endowed with another Lie bracket operation. Making use of this Lie bracket one can generate new characteristic classes involving higher derivatives of the homological vector field. The simplest characteristic classes are illustrated by the examples relating them to anomalies in the traditional BV or BFV-BRST theory and to characteristic classes of (singular) foliations
Gravitating instantons in 3 dimensions
International Nuclear Information System (INIS)
We study the Einstein-Chern-Simons gravity coupled to Yang-Mills-Higgs theory in three-dimensional Euclidean space with a cosmological constant. The classical equations reduce to Bogomol'nyi type first order equations in curved space. There are BPS type gauge theory instanton (monopole) solutions of finite action in a gravitational instanton which itself has a finite action. We also discuss gauge theory instantons in the vacuum (zero action) AdS space. In addition we point out to some exact solutions which are singular. (c) 2000 The American Physical Society
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.
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.
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.
A simple example of a classical gauge transformation
Whitten, R. C.
1983-01-01
Attention is given to the manner in which the interaction of a gravitational field with a diffusing gas is induced by a gauge transformation. Since the gas can be thought of as a field, the diffusion process may be represented by a Lagrangian density with the symmetry property of invariance under translation. While this property is lost when the field interacts with a static gravitational field, it is formally restored when an appropriate gauge transformation is performed. This ascription of field properties to a gas offers an illuminating illustration of the coupling of matter to a gauge field within the context of classical mechanics.
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)
Axial anomalies of Lifshitz fermions
International Nuclear Information System (INIS)
We compute the axial anomaly of a Lifshitz fermion theory with anisotropic scaling z = 3 which is minimally coupled to geometry in 3+1 space-time dimensions. We find that the result is identical to the relativistic case using path integral methods. An independent verification is provided by showing with spectral methods that the η-invariant of the Dirac and Lifshitz fermion operators in three dimensions are equal. Thus, by the integrated form of the anomaly, the index of the Dirac operator still accounts for the possible breakdown of chiral symmetry in non-relativistic theories of gravity. We apply this framework to the recently constructed gravitational instanton backgrounds of Horava-Lifshitz theory and find that the index is non-zero provided that the space-time foliation admits leaves with harmonic spinors. Using Hitchin's construction of harmonic spinors on Berger spheres, we obtain explicit results for the index of the fermion operator on all such gravitational instanton backgrounds with SU(2) x U(1) isometry. In contrast to the instantons of Einstein gravity, chiral symmetry breaking becomes possible in the unimodular phase of Horava-Lifshitz theory arising at λ = 1/3 provided that the volume of space is bounded from below by the ratio of the Ricci to Cotton tensor couplings raised to the third power. Some other aspects of the anomalies in non-relativistic quantum field theories are also discussed. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
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...
International Nuclear Information System (INIS)
From the viewpoint of gauge gravitational theories, the path dependent gravitational phase factors define the Lorentz transformations between the local inertial coordinate systems of different positions. With this point we show that the spectral shifts in the curved spacetime, such as the gravitational and cosmological redshifts, can be understood as Doppler shifts. All these shifts are interpreted in a unified way as being originated from the relative motion of the free falling observers instantaneously static with the wave source and the receiver respectively. The gravitational phase factor of quantum systems in the curved spacetime is also discussed. (paper)
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...
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.
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)
New insight into BRST anomalies in superstring theory
International Nuclear Information System (INIS)
Based on the extended BRST formalism of Batalin, Fradkin and Vilkovisky, we perform a general algebraic analysis of the BRST anomalies in superstring theory of Neveu-Schwarz-Ramond. Consistency conditions on the BRST anomalies are completely solved. The genuine super-Virasoro anomaly is identified with the essentially unique solution to the consistency condition without any reference to a particular gauge for the 2D supergravity fields. In a configuration space where metric and gravitino fields are properly constructed, the general form of the super-Weyl anomaly is obtained from the super-Virasoro anomaly as its descendant. We give a novel local action of super-Liouville type, which plays a role of Wess-Zumino-Witten term shifting the super-Virasoro anomaly into the super-Weyl anomaly. These results reveal a hierarchical relationship in the BRST anomalies. ((orig.))
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)
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.)
Quantum 3D tensionless string in light-cone gauge
International Nuclear Information System (INIS)
We discuss the quantization of a tensionless closed string in light-cone gauge. It is known that by using a Hamiltonian BRST scheme a tensionless string has no Lorentz anomaly in any space-time dimensions and no anomaly for the space-time conformal symmetry in two dimensions. In this paper, we show that a 3d tensionless closed string in light-cone gauge also has no anomaly of space-time conformal symmetry. We also study the spectrum of a 3d tensionless closed string
Quantum 3D tensionless string in light-cone gauge
Kenta Murase
2014-01-01
We discuss the quantization of a tensionless closed string in light-cone gauge. It is known that by using a Hamiltonian BRST scheme a tensionless string has no Lorentz anomaly in any space-time dimensions and no anomaly for the space-time conformal symmetry in two dimensions. In this paper, we show that a 3d tensionless closed string in light-cone gauge also has no anomaly of space-time conformal symmetry. We also study the spectrum of a 3d tensionless closed string.
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.
Energy Technology Data Exchange (ETDEWEB)
Shnir, Ya. M., E-mail: shnir@theor.jinr.ru [Joint Institute for Nuclear Research (Russian Federation)
2015-12-15
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.
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)
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)
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...
Spiegel, Edward A
1998-01-01
Calculations of the stopping power of a medium lead to divergent integrals in gravitational theory as they do in the analogous electromagnetic problem. In the em case, one introduces (normally in an arbitrary manner) the Debye length as a cutoff at large distances to remove the divergence. We show here that in the Newtonian gravitational analogue the distant cutoff problem is solved by including the self-gravity of the medium. Then the Jeans length appears naturally as a cutoff. Despite the d...
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.
Wetterich, C.(Institute for Theoretical Physics, Heidelberg University, Heidelberg, D-69120, Germany)
2013-01-01
Scalar lattice gauge theories are models for scalar fields with local gauge symmetries. No fundamental gauge fields, or link variables in a lattice regularization, are introduced. The latter rather emerge as collective excitations composed from scalars. For suitable parameters scalar lattice gauge theories lead to confinement, with all continuum observables identical to usual lattice gauge theories. These models or their fermionic counterpart may be helpful for a realization of gauge theories...
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
Energy Technology Data Exchange (ETDEWEB)
Stieberger, Stephan, E-mail: stephan.stieberger@mpp.mpg.de [Max-Planck-Institut für Physik, Werner-Heisenberg-Institut, 80805 München (Germany); Taylor, Tomasz R. [Department of Physics, Northeastern University, Boston, MA 02115 (United States)
2014-12-12
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.
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.
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.
Gravitation, the 'Dark Matter' Effect and the Fine Structure Constant
Reginald T. Cahill
2004-01-01
Gravitational anomalies such as the mine/borehole g anomaly, the near-flatness of the spiral galaxy rotation-velocity curves, currently interpreted as a `dark matter' effect, the absence of that effect in ordinary elliptical galaxies, and the ongoing problems in accurately determining Newton's gravitational constant G_N are explained by a generalisation of the Newtonian theory of gravity to a fluid-flow formalism with one new dimensionless constant. By analysing the borehole data this constan...
International Nuclear Information System (INIS)
We propose a model for cosmic inflation which is based on an effective description of strongly interacting, nonsupersymmetric matter within the framework of dynamical Abelian projection and centerization. The underlying gauge symmetry is assumed to be SU(N+1) with N>>1. Appealing to a thermodynamical treatment, the ground-state structure of the model is classically determined by a potential for the inflaton field (dynamical monopole condensate) which allows for nontrivially BPS saturated and thereby stable solutions. For TP this leads to decoupling of gravity from the inflaton dynamics. The ground state dynamics implies a heat capacity for the vacuum leading to inflation for temperatures comparable to the mass scale M of the potential. The dynamics has an attractor property. In contrast with the usual slow-roll paradigm we have m>>H during inflation. As a consequence, density perturbations generated from the inflaton are irrelevant for the formation of large-scale structure, and the model has to be supplemented with an inflaton independent mechanism for the generation of spatial curvature perturbations. Within a small fraction of the Hubble time inflation is terminated by a transition of the theory to its center symmetric phase. The spontaneously broken ZN+1 symmetry stabilizes relic vector bosons in the epochs following inflation. These heavy relics contribute to the cold dark matter of the universe and potentially originate the UHECRs beyond the GZK bound
Probing inflation models with gravitational waves
Domcke, Valerie
2016-01-01
A direct detection of primordial gravitational waves is the ultimate probe for any inflation model. While current CMB bounds predict the generic scale-invariant gravitational wave spectrum from slow-roll inflation to be below the reach of upcoming gravitational wave interferometers, this prospect may dramatically change if the inflaton is a pseudoscalar. In this case, a coupling to any abelian gauge field leads to a tachyonic instability for the latter and hence to a new source of gravitational waves, directly related to the dynamics of inflation. In this contribution we discuss how this setup enables the upcoming gravitational wave interferometers advanced LIGO/VIRGO and eLISA to probe the microphysics of inflation, distinguishing between different universality classes of single-field slow-roll inflation models. We find that the prime candidate for an early detection is a Starobinsky-like model.
Sluse, Dominique; Chantry, Virginie; Magain, Pierre; Courbin, F.; Meylan, G.
2011-01-01
Gravitationally lensed quasars can be used as powerful cosmological and astrophysical probes. We can (i) infer the Hubble constant H0 based on the so-called time-delay technique, (ii) unveil substructures along the line-of-sight toward distant galaxies, and (iii) compare the shape and the slope of baryons and dark matter distributions in the inner regions of galaxies. To reach these goals, we need high-accuracy astrometry of the quasar images relative to the lensing galaxy and morphology meas...
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 ...
Anomalies in covariant W-gravity
International Nuclear Information System (INIS)
We consider free scalar matter covariantly coupled to background W-gravity. Expanding to second order in the W-gravity fields, we study the appropriate anomalous Ward-Takahashi identities and find the counterterms which maintain diffeomorphism invariance and its W-analogue. We see that a redefinition of the vielbein transformation rule under W-diffeomorphism is required in order to cancel nonlocal contributions to the anomaly. Moreover, we explicitly write all gauge invariances at this order. Some consequences of these results for the chiral gauge quantization are discussed. (orig.)
Pseudospectral method for gravitational wave collapse
Hilditch, David; Weyhausen, Andreas; Brügmann, Bernd
2016-03-01
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 nonvanishing 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 employ the Cartoon method to efficiently evolve axisymmetric data in our 3 +1 -dimensional code. We perform test evolutions of the Schwarzschild spacetime perturbed by gravitational waves and by gauge pulses, both to demonstrate the use of our black-hole excision scheme and for comparison with earlier results. Finally, numerical evolutions of supercritical Brill waves are presented to demonstrate durability of the excision scheme for the dynamical formation of a black hole.
Anomalies of discrete symmetries in three dimensions and group cohomology
Kapustin, Anton
2014-01-01
We study 't Hooft anomalies for a global discrete internal symmetry G. We construct examples of bosonic field theories in three dimensions with a non-vanishing 't Hooft anomaly for a discrete global symmetry. We also construct field theories in three dimensions with a global discrete internal symmetry G_1 x G_2 such that gauging G_1 necessarily breaks G_2 and vice versa. This is analogous to the Adler-Bell-Jackiw axial anomaly in four dimensions and parity anomaly in three dimensions.
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.)
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
Supersymmetric gauge theories from string theory
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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)
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.)
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
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
Covariant Quiver Gauge Theories
Szabo, Richard J
2014-01-01
We consider dimensional reduction of gauge theories with arbitrary gauge group in a formalism based on equivariant principal bundles. For the classical gauge groups we clarify the relations between equivariant principal bundles and quiver bundles, and show that the reduced quiver gauge theories are all generically built on the same universal symmetry breaking pattern. The formalism enables the dimensional reduction of Chern-Simons gauge theories in arbitrary odd dimensionalities. The reduced model is a novel Chern-Simons-Higgs theory consisting of a Chern-Simons term valued in the residual gauge group plus a higher order gauge and diffeomorphism invariant coupling of Higgs fields with the gauge fields. We study the moduli spaces of solutions, which in some instances provide geometric representations of certain quiver varieties as moduli spaces of flat invariant connections. As physical applications, we consider dimensional reductions involving non-compact gauge supergroups as a means for systematically induci...
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
Anomaly equations and the persistent mass condition
International Nuclear Information System (INIS)
Vector SU(Nsub(c)) gauge theories with nsub(f) flavors in the fundamental representation are considered. We prove that if the persistent mass condition is assumed, the two anomaly equations are identical and flavor independent for nsub(f)>=3. Integer solutions exist only for nsub(f)=2. The necessity of a separate discussion for 2<=nsub(f)<=Nsub(c) is explained. (author)
Anomaly equations and the persistent mass condition
International Nuclear Information System (INIS)
Vector SU(Nsub(c)) gauge theories with nsub(f) flavors in the fundamental representation are considered. We prove that if the persistent mass condition is assumed, the two anomaly equations are identical and flavor independent for nsub(f) >= 3. Integer solutions exist only for nsub(f) = 2. The necessity of a separate discussion for 2 <= nsub(f) <= Nsub(c) is explained. (orig.)
Wodzicki residue and anomalies of current algebras
Mickelsson, J
1994-01-01
The commutator anomalies (Schwinger terms) of current algebras in 3+1 dimensions are computed in terms of the Wodzicki residue of pseudodifferential operators; the result can be written as a (twisted) Radul 2-cocycle for the Lie algebra of PSDOs. The construction of the (second quantized) current algebra is closely related to a geometric renormalization of the interaction Hamiltonian H_I=j_{\\mu} A^{\\mu} in gauge theory.
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^{~\
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.
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
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.
Thorne, K S
1995-01-01
This article reviews current efforts and plans for gravitational-wave detection, the gravitational-wave sources that might be detected, and the information that the detectors might extract from the observed waves. Special attention is paid to (i) the LIGO/VIRGO network of earth-based, kilometer-scale laser interferometers, which is now under construction and will operate in the high-frequency band (1 to 10^4 Hz), and (ii) a proposed 5-million-kilometer-long Laser Interferometer Space Antenna (LISA), which would fly in heliocentric orbit and operate in the low-frequency band (10^{-4} to 1 Hz). LISA would extend the LIGO/VIRGO studies of stellar-mass (M\\sim2 to 300 M_\\odot) black holes into the domain of the massive black holes (M\\sim1000 to 10^8M_\\odot) that inhabit galactic nuclei and quasars.
Utilitarian Supersymmetric Gauge Model of Particle Interactions
Ma, Ernest
2010-01-01
A remarkable U(1) gauge extension of the supersymmetric standard model was proposed eight years ago. It is anomaly-free, has no mu term, and conserves baryon and lepton numbers automatically. The phenomenology of a specific version of this model is discussed. In particular, leptoquarks are predicted, with couplings to the heavy singlet neutrinos, the scalar partners of which may be components of dark matter. The Majorana neutrino mass matrix itself may have two zero subdeterminants.
Utilitarian supersymmetric gauge model of particle interactions
International Nuclear Information System (INIS)
A remarkabale U(1) gauge extension of the supersymmetric standard model was proposed 8 years ago. It is anomaly free, has no μ term, and conserves baryon and lepton numbers automatically. The phenomenology of a specific version of this model is discussed. In particular, leptoquarks are predicted, with couplings to the heavy singlet neutrinos, the scalar partners of which may be components of dark matter. The Majorana neutrino mass matrix itself may have two zero subdeterminants.
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...
Eliminating the chiral anomaly via symplectic embedding approach
Mendes, A C R; Oliveira, W
2009-01-01
The quantization of the chiral Schwinger model $(\\chi QED_{2})$ with one-parameter class Faddeevian regularization is hampered by the chiral anomaly, i.e., the Gauss law commutator exhibits Faddeev's anomaly. To overcome this kind of problem, we propose to eliminate this anomaly by embedding the theory through a new gauge-invariant formalism based on the enlargement of the phase space with the introduction of Wess-Zumino(WZ) fields and the symplectic approach. This process opens up a possibility to formulate different, but dynamically equivalent, gauge invariant versions for the model and also gives a geometrical interpretation to the arbitrariness presents on the BFFT and iterative conversion methods. Further, we observe that the elimination of the chiral anomaly imposes a condition on the chiral parameters present on the original model and on the WZ sector.
A first look at Weyl anomalies in shape dynamics
International Nuclear Information System (INIS)
One of the more popular objections towards shape dynamics is the suspicion that anomalies in the spatial Weyl symmetry will arise upon quantization. The purpose of this short paper is to establish the tools required for an investigation of the sort of anomalies that can possibly arise. The first step is to adapt to our setting Barnich and Henneaux's formulation of gauge cohomology in the Hamiltonian setting, which serve to decompose the anomaly into a spatial component and time component. The spatial part of the anomaly, i.e., the anomaly in the symmetry algebra itself ([Ω, Ω] ∝ ℏ instead of vanishing) is given by a projection of the second ghost cohomology of the Hamiltonian BRST differential associated to Ω, modulo spatial derivatives. The temporal part, [Ω, H] ∝ ℏ is given by a different projection of the first ghost cohomology and an extra piece arising from a solution to a functional differential equation. Assuming locality of the gauge cohomology groups involved, this part is always local. Assuming locality for the gauge cohomology groups, using Barnich and Henneaux's results, the classification of Weyl cohomology for higher ghost numbers performed by Boulanger, and following the descent equations, we find a complete characterizations of anomalies in 3+1 dimensions. The spatial part of the anomaly and the first component of the temporal anomaly are always local given these assumptions even in shape dynamics. The part emerging from the solution of the functional differential equations explicitly involves the shape dynamics Hamiltonian, and thus might be non-local. If one restricts this extra piece of the temporal anomaly to be also local, then overall no Weyl anomalies, either temporal or spatial, emerge in the 3+1 case
Stringy explanation of b → sℓ + ℓ - anomalies
Celis, Alejandro; Feng, Wan-Zhe; Lüst, Dieter
2016-02-01
We show that the recent anomalies in b → sℓ + ℓ - transitions observed by the LHCb collaboration can be accommodated within string motivated models with a low mass Z' gauge boson. Such Z' 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 → sℓ + ℓ - anomalies via a stringy Z' sets important restrictions on these viable D-brane constructions.
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.
Renormalization of gauge theories without cohomology
Anselmi, Damiano
2013-07-01
We investigate the renormalization of gauge theories without assuming cohomological properties. We define a renormalization algorithm that preserves the Batalin-Vilkovisky master equation at each step and automatically extends the classical action till it contains sufficiently many independent parameters to reabsorb all divergences into parameter-redefinitions and canonical transformations. The construction is then generalized to the master functional and the field-covariant proper formalism for gauge theories. Our results hold in all manifestly anomaly-free gauge theories, power-counting renormalizable or not. The extension algorithm allows us to solve a quadratic problem, such as finding a sufficiently general solution of the master equation, even when it is not possible to reduce it to a linear (cohomological) problem.
Renormalization of gauge theories without cohomology
Energy Technology Data Exchange (ETDEWEB)
Anselmi, Damiano [Universita di Pisa, Dipartimento di Fisica ' ' Enrico Fermi' ' , Pisa (Italy); INFN, Sezione di Pisa (Italy)
2013-07-15
We investigate the renormalization of gauge theories without assuming cohomological properties. We define a renormalization algorithm that preserves the Batalin-Vilkovisky master equation at each step and automatically extends the classical action till it contains sufficiently many independent parameters to reabsorb all divergences into parameter-redefinitions and canonical transformations. The construction is then generalized to the master functional and the field-covariant proper formalism for gauge theories. Our results hold in all manifestly anomaly-free gauge theories, power-counting renormalizable or not. The extension algorithm allows us to solve a quadratic problem, such as finding a sufficiently general solution of the master equation, even when it is not possible to reduce it to a linear (cohomological) problem. (orig.)
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
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.
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
Nonperturbative Formulas for Central Functions of Supersymmetric Gauge Theories
Anselmi, D.; Freedman, D. Z.; Grisaru, M. T.; Johansen, A. A.
1997-01-01
For quantum field theories that flow between ultraviolet and infrared fixed points, central functions, defined from two-point correlators of the stress tensor and conserved currents, interpolate between central charges of the UV and IR critical theories. We develop techniques that allow one to calculate the flows of the central charges and that of the Euler trace anomaly coefficient in a general N=1 supersymmetric gauge theory. Exact, explicit formulas for $SU(N_c)$ gauge theories in the conf...
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.
HAMAMOTO, Shinji
1995-01-01
The usual prescription for constructing gauge-invariant Lagrangian is generalized to the case where a Lagrangian contains second derivatives of fields as well as first derivatives. Symmetric tensor fields in addition to the usual vector fields are introduced as gauge fields. Covariant derivatives and gauge-field strengths are determined.
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
Effects of local mass anomalies in Eoetvoes-like experiments
International Nuclear Information System (INIS)
We consider in detail the effects of local mass anomalies in Eoetvoes-like experiments. It is shown that in the presence of an intermediate-range non-gravitational force, the dominant contributions to both the sign and magnitude of the Eoetvoes anomaly may come from nearby masses and not from the earth as a whole. This observation has important implications in the design and interpretation of future experiments, and in the formulation of unified theories incorporating new intermediate-range forces
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
Relativistic Transverse Gravitational Redshift
Mayer, A. F.
2012-12-01
The parametrized post-Newtonian (PPN) formalism is a tool for quantitative analysis of the weak gravitational field based on the field equations of general relativity. This formalism and its ten parameters provide the practical theoretical foundation for the evaluation of empirical data produced by space-based missions designed to map and better understand the gravitational field (e.g., GRAIL, GRACE, GOCE). Accordingly, mission data is interpreted in the context of the canonical PPN formalism; unexpected, anomalous data are explained as similarly unexpected but apparently real physical phenomena, which may be characterized as ``gravitational anomalies," or by various sources contributing to the total error budget. Another possibility, which is typically not considered, is a small modeling error in canonical general relativity. The concept of the idealized point-mass spherical equipotential surface, which originates with Newton's law of gravity, is preserved in Einstein's synthesis of special relativity with accelerated reference frames in the form of the field equations. It was not previously realized that the fundamental principles of relativity invalidate this concept and with it the idea that the gravitational field is conservative (i.e., zero net work is done on any closed path). The ideal radial free fall of a material body from arbitrarily-large range to a point on such an equipotential surface (S) determines a unique escape-velocity vector of magnitude v collinear to the acceleration vector of magnitude g at this point. For two such points on S separated by angle dφ , the Equivalence Principle implies distinct reference frames experiencing inertial acceleration of identical magnitude g in different directions in space. The complete equivalence of these inertially-accelerated frames to their analogous frames at rest on S requires evaluation at instantaneous velocity v relative to a local inertial observer. Because these velocity vectors are not parallel, a symmetric energy potential exists between the frames that is quantified by the instantaneous Δ {v} = v\\cdot{d}φ between them; in order for either frame to become indistinguishable from the other, such that their respective velocity and acceleration vectors are parallel, a change in velocity is required. While the qualitative features of general relativity imply this phenomenon (i.e., a symmetric potential difference between two points on a Newtonian `equipotential surface' that is similar to a friction effect), it is not predicted by the field equations due to a modeling error concerning time. This is an error of omission; time has fundamental geometric properties implied by the principles of relativity that are not reflected in the field equations. Where b is the radius and g is the gravitational acceleration characterizing a spherical geoid S of an ideal point-source gravitational field, an elegant derivation that rests on first principles shows that for two points at rest on S separated by a distance d << b, a symmetric relativistic redshift exists between these points of magnitude z = gd2/bc^2, which over 1 km at Earth sea level yields z ˜{10-17}. It can be tested with a variety of methods, in particular laser interferometry. A more sophisticated derivation yields a considerably more complex predictive formula for any two points in a gravitational field.
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.)
International Nuclear Information System (INIS)
The reinterpretation of the BRS equations of Quantum Field Theory as the Maurer Cartan equation of a classical principal fiber bundle leads to a simple gauge invariant classification of the anomalies in Yang Mills theory and gravity
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)
Gauge theory of quantum gravity
Nam, Cao H
2014-01-01
The gravity is classically formulated as the geometric curvature of the space-time in general relativity which is completely different from the other well-known physical forces. Since seeking a quantum framework for the gravity is a great challenge in physics. Here we present an alternative construction of quantum gravity in which the quantum gravitational degrees of freedom are described by the non-Abelian gauge fields characterizing topological non-triviality of the space-time. The quantum dynamics of the space-time thus corresponds to the superposition of the distinct topological states. Its unitary time evolution is described by the path integral approach. This result will also be suggested to solve some major problems in physics of the black holes.
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.
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.
Improved moving puncture gauge conditions for compact binary evolutions
Etienne, Zachariah B.; Baker, John G.; Paschalidis, Vasileios; Kelly, Bernard J.; Shapiro, Stuart L.
2014-09-01
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 ˜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.
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...
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-Poincar 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).
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...
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...
Ward-Takahashi identities for Abelian chiral gauge theories
de Lima, Ana Paula Cardoso Rodrigues; Dias, Sebastião Alves
2016-04-01
By considering a general Abelian chiral gauge theory, we investigate the behavior of anomalous Ward-Takahashi (WT) identities concerning their prediction for the usual relationship between the vertex and two-point fermion functions. Using gauge anomaly vanishing results, we show that the usual (in the nonanomalous case) WT identity connecting the vertex and two-point fermion 1PI functions is modified for Abelian chiral gauge theories. The modification, however, implies a relation between fermion and charge renormalization constants that can be important in a future study of renormalization of such theories.
Gravitational wave stress tensor from the linearised field equations
Balbus, Steven A
2016-01-01
A conserved stress energy tensor for weak field gravitational waves in standard general relativity is derived directly from the linearised wave equation alone, for an arbitrary gauge. The form of the tensor leads directly to the classical expression for the outgoing wave energy in any harmonic gauge. The method described here, however, is a much simpler, shorter, and more physically motivated approach than is the customary procedure, which involves a lengthy and cumbersome second-order (in wave-amplitude) calculation starting with the Einstein tensor. Our method has the added advantage of exhibiting the direct coupling between the outgoing energy flux in gravitational waves and the work done by the gravitational field on the sources. For nonharmonic gauges, the derived wave stress tensor has an index asymmetry. This coordinate artefact may be removed by techniques similar to those used in classical electrodynamics (where this issue also arises), but only by appeal to a more lengthy calculation. For any harmon...
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.)
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.
Topology, charged particles and anomalies in quantum mechanics
International Nuclear Information System (INIS)
The quantisation of a particle coupled to a U(1) gauged field and propagating on a generic manifold M with a group action fg of a group G is studied. It is shown that this model suffers from local and global anomalies associated with the symmetries that the group action fg generates. These anomalies have a topological interpretation and appear as obstructions to constructing unitary representations of the group G on the Hilbert space of the quantum mechanical system. Moreover, the relation between the global anomalies and the torsion part in the cohomology of M and G is examined. (orig.)
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)
Non-Relativistic Limit of Dirac Equations in Gravitational Field and Quantum Effects of Gravity
Wu, N
2006-01-01
Based on unified theory of electromagnetic interactions and gravitational interactions, the non-relativistic limit of the equation of motion of a charged Dirac particle in gravitational field is studied. From the Schrodinger equation obtained from this non-relativistic limit, we could see that the classical Newtonian gravitational potential appears as a part of the potential in the Schrodinger equation, which can explain the gravitational phase effects found in COW experiments. And because of this Newtonian gravitational potential, a quantum particle in earth's gravitational field may form a gravitationally bound quantized state, which had already been detected in experiments. Three different kinds of phase effects related to gravitational interactions are discussed in this paper, and these phase effects should be observable in some astrophysical processes. Besides, there exists direct coupling between gravitational gauge field and quantum spin, radiation caused by this coupling can be used to directly determ...
Anomaly conditions for non-Abelian finite family symmetries
International Nuclear Information System (INIS)
Assuming that finite family symmetries are gauged, we derive discrete anomaly conditions for various non-Abelian groups. We thus provide new constraints for flavor model building, in which discrete non-Abelian symmetries are employed to explain the tri-bimaximal mixing pattern in the lepton sector.
Origin of Weyl Anomaly as Pair Production in Dirac Sea
Habara, Yoshinobu; Ninomiya, Masao
2015-01-01
Using Dirac sea picture for both left and right moving Weyl fermion (massless fermions) in $1+1$ dimensional world with a general relativity metric field we calculate the Weyl anomaly. That is to say we calculate the trace of the energy-momentum tensor $T_{\\mu}^{\\> \\mu}$ arising from the fermions. With the gauge choice ansatz $g_{\\mu \
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
Unification of Gravitational and Electromagnetic Fields in Riemannian Geometry
Chang, Yi-Fang
2009-01-01
The gravitational field and the source-free electromagnetic field can be unified preliminarily by the equations in the Riemannian geometry, both are contractions of im and ik, respectively. So it will be equivalent to the Yang gravitational equations. From this we can obtain the Lorentz equations of motion, the first system and second source-free system of Maxwell field equations. This unification can be included in the gauge theory, and the unified gauge group is GL(2,C), which is just the s...
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.
The Road to Gravitational S-Duality
Garcia-Compen, H.; Obregn, 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
Garca-Compan, H; Ramrez, 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.
A possible quantum probability increase of the cylindrical gravitational field
Bar, D
2007-01-01
As known, the cylindrical gravitational field (wave) have been canonically quantized and its wave function, as the quantum one, interpreted in probability terms. We show in this work, using quantum Zeno methods, that this probability may be substantially increased and even approach unity. For that we first show, in detailed manner, that the cylindrical gravitational field may be discussed in the commutation number representation. We also discuss this field in the transverse-traceless (TT) gauge and calculate the related trapped surface.
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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
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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
Electrodinmica semiclsica, invariante gauge?
Zambrano, D. E.; Sanchez, J.A.; Morales, J.
2014-01-01
: En conocido que cualquier ley fsica que involucre la interaccin electromagntica se puede expresar en trminos de los potenciales electrodinmicos generales A y ?, y que dicha ley permanece inalterada al aplicarle las llamasd transformaciones de gauge, es decir, la teora es invariante gauge. En el presente trabajo analizamos el caso de la electrodinmica clsica, para la cual verificamos la invariancia gauge, en la estructura de la ecuacin de Schrdinger y en los valores propios del ham...
Tumbling and complementarity in a chiral gauge theory
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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.)
Trace extensions, determinant bundles, and gauge group cocycles
Arnlind, J; Arnlind, Joakim; Mickelsson, Jouko
2002-01-01
We study the geometry of determinant line bundles associated to Dirac operators on compact odd dimensional manifolds. Physically, these arise as (local) vacuum line bundles in quantum gauge theory. We give a simplified derivation of the commutator anomaly formula using a construction based on noncyclic trace extensions and associated multiplicative renormalized determinants.
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 liklehood of this confining phase ever being realized in practice is discussed. (orig.)
The Wess-Zumino gauge is a 'good' gauge
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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 Rξ gauge, which are 'bad' gauges. (orig.)
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.
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.
David, T. J.
1982-01-01
The Poland anomaly is usually a non-genetic malformation syndrome. This paper reports two second cousins who both had a typical left sided Poland anomaly, and this constitutes the first recorded case of this condition affecting more than one member of a family. Despite this, for the purposes of genetic counselling, the Poland anomaly can be regarded as a sporadic condition with an extremely low recurrence risk.
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-based network detect...
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.
Bianchi, Massimo; Morales, Jose F.
2000-03-01
We show that massless RR tadpoles in vacuum configurations with open and unoriented strings are always related to anomalies. RR tadpoles arising from sectors of the internal SCFT with non-vanishing Witten index are in one-to-one correspondence with conventional irreducible anomalies. The anomalous content of the remaining RR tadpoles can be disclosed by considering anomalous amplitudes with higher numbers of external legs. We then provide an explicit parametrization of the anomaly polynomial in terms of the boundary reflection coefficients, i.e. one-point functions of massless RR fields on the disk. After factorization of the reducible anomaly, we extract the relevant WZ couplings in the effective lagrangians.
International Nuclear Information System (INIS)
Results of astronomical observations over the past few years have caused an active search for 'dark' matter and 'dark' energy. To know the nature of 'dark' energy, it is first necessary to know the nature of gravitation. However, even standard gravitational energy still remains a problem in the modern theory of gravitation. We have applied special optical methods to the solution of the problem of gravitational energy. In the process of research two new features of the propagation of light in gravitational fields are found. The dependency of the inertial mass of accelerated particles on the action of the gravitation is defined. The problem of localization of gravitational energy is solved also. (author)
Apparent anomalies in borehole and seafloor gravity measurements
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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...
Hall viscosity from elastic gauge fields in Dirac crystals
Cortijo, Alberto; Landsteiner, Karl; Vozmediano, Mara 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...
Non-analyticities in three-dimensional gauge theories
Asorey, M; López, J L
2004-01-01
Quantum fluctuations generate in three-dimensional gauge theories not only radiative corrections to the Chern-Simons coupling but also non-analytic terms in the effective action. We review the role of those terms in gauge theories with massless fermions and Chern-Simons theories. The explicit form of non-analytic terms turns out to be dependent on the regularization scheme and in consequence the very existence of phenomena like parity and framing anomalies becomes regularization dependent. In particular we find regularization regimes where both anomalies are absent. Due to the presence of non-analytic terms the effective action becomes not only discontinuous but also singular for some background gauge fields which include sphalerons. The appearence of this type of singularities is linked to the existence of nodal configurations in physical states and tunneling suppression at some classical field configurations. In the topological field theory the number of physical states may also become regularization depend...
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.
Gravitating non-Abelian cosmic strings
Santo, Antônio de Padua
2015-01-01
In this paper we study regular cosmic string solutions of the non-Abelian Higgs model coupled with the Einstein gravity. In order to do that, we constructed a set of coupled differential ordinary equation. Because there is no closed solution for this set of equations, we solve it numerically. The solutions that we are interested in asymptote to a flat space-time with a planar angle deficit. This model under consideration present two bosonic sectors, besides the non-Abelian gauge one, coupled minimally with the gravitational fields. The two bosonic sectors may present a direct coupling, which plays an important role on the behavior of the matter and gauge fields and also on the behavior on the geometry of the spacetime. We explicitly analyze the behaviors of the energy density and planar angle deficit as function of the energy scale where the gauge symmetry is spontaneously broken and the coupling interaction between the bosonic sectors.
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...
Supersymmetric gauge theories with a free algebra of invariants
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We study the low-energy dynamics of all N=1 supersymmetric gauge theories whose basic gauge-invariant fields are unconstrained. This set includes all theories whose matter Dynkin index is less than the index of the adjoint representation. We study the dynamically generated superpotential in these theories, and show that there is a W=0 branch if and only if anomaly matching is satisfied at the origin. An interesting example studied in detail is SO(13) with a spinor, a theory with a dynamically generated W and no anomaly matching at the origin. It flows via the Higgs mechanism to SU(6) with a three-index antisymmetric tensor, a theory with a W=0 branch and anomaly matching at the origin. (orig.)
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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
Ardalan, F.; Arfaei, H.; Ghasemkhani, M.; Sadooghi, N.
2011-01-01
A hidden generalized gauge symmetry of a cutoff QED is used to show the renormalizability of QED. In particular, it is shown that corresponding Ward identities are valid all along the renormalization group flow. The exact Renormalization Group flow equation corresponding to the effective action of a cutoff lambda phi^4 theory is also derived. Generalization to any gauge group is indicated.
Energy Technology Data Exchange (ETDEWEB)
Bartholomew, M. J. [Brookhaven National Lab. (BNL), Upton, NY (United States)
2016-01-01
To improve the quantitative description of precipitation processes in climate models, the Atmospheric Radiation Measurement (ARM) Climate Research Facility deployed rain gauges located near disdrometers (DISD and VDIS data streams). This handbook deals specifically with the rain gauges that make the observations for the RAIN data stream. Other precipitation observations are made by the surface meteorology instrument suite (i.e., MET data stream).
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...
Hamiltonian dynamics of gauge theories of gravity
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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
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.
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.
Some Friedmann cosmological solutions in the scale covariant theory of gravitation
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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.
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) ∼ 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)≅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
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
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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.)
Field-theory interpretation of the gravitational interaction in electrodynamics
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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
Anomaly cancellation for super-W-gravity
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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
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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.
Gravitational analogue of the Witten effect
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Foda, O. (International Centre for Theoretical Physics, Trieste (Italy))
1985-07-22
In the presence of massive fermions, and assuming a non-vanishing theta-parameter as the only source of CP violation, the Witten effect (a shift in the electric charge of a magnetic monopole due to CP non-conservation) is shown to follow from an anomalous chiral commutator. Next, given the gravitational contribution to the chiral anomaly, the corresponding anomalous commutator for Dirac fermion currents in a gravitational background is derived. From that, we infer the equivalence of a thetaR tildeR term in the lagrangian to a shift in the mass parameter of the NUT metric, in proportion to theta. This is interpreted as the gravitational analogue of the Witten effect. Its relevance to certain Kaluza-Klein monopoles is briefly discussed.
The gravitational analogue of the Witten effect
International Nuclear Information System (INIS)
In the presence of massive fermions, and assuming a non-vanishing theta-parameter as the only source of CP-violation, the Witten effect [a shift in the electric charge of a magnetic monopole due to CP-non-conservation] is shown to follow from an anomalous chiral commutator. Next, given the gravitational contribution to the chiral anomaly, the corresponding anomalous commutator for Dirac fermion currents in a gravitational background is derived. From that, we infer the equivalence of a theta R-tilde R term in the Lagrangian to a shift in the mass parameter of the NUT metric, in proportion to theta. This is interpreted as the gravitational analogue of the Witten effect. Its relevance to certain Kaluza-Klein monopoles is briefly discussed. (author)
The gravitational analogue of the Witten effect
International Nuclear Information System (INIS)
In the presence of massive fermions, and assuming a non-vanishing theta-parameter as the only source of CP violation, the Witten effect (a shift in the electric charge of a magnetic monopole due to CP non-conservation) is shown to follow from an anomalous chiral commutator. Next, given the gravitational contribution to the chiral anomaly, the corresponding anomalous commutator for Dirac fermion currents in a gravitational background is derived. From that, we infer the equivalence of a thetaR tildeR term in the lagrangian to a shift in the mass parameter of the NUT metric, in proportion to theta. This is interpreted as the gravitational analogue of the Witten effect. Its relevance to certain Kaluza-Klein monopoles is briefly discussed. (orig.)
Post-Einsteinian tests of linearized gravitation
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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
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 A1u11-u22 and A2u12 , and conclude by offering some scenarios in fundamental physics that this peculiar field could help to realize.
Quantum critical behavior of semisimple gauge theories
Esbensen, Jacob Kamuk; Ryttov, Thomas A.; Sannino, Francesco
2016-02-01
We study the perturbative phase diagram of semisimple fermionic gauge theories resembling the Standard Model. We investigate an S U (N ) gauge theory with M Dirac flavors where we gauge first an S U (M )L and then an S U (2 )L⊂S U (M )L of the original global symmetry S U (M )L×S U (M )R×U (1 ) of the theory. To avoid gauge anomalies we add leptonlike particles. At the two-loop level an intriguing phase diagram appears. We uncover phases in which one, two or three fixed points exist and discuss the associated flows of the coupling constants. We discover a phase featuring complete asymptotic freedom and simultaneously an interacting infrared fixed point in both couplings. The analysis further reveals special renormalization group trajectories along which one coupling displays asymptotic freedom and the other asymptotic safety, while both flowing in the infrared to an interacting fixed point. These are safety free trajectories. We briefly sketch out possible phenomenological implications, among which an independent way to generate near-conformal dynamics à la walking is investigated.