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1

Gauged BRST symmetry and covariant gravitational anomalies  

Energy Technology Data Exchange (ETDEWEB)

We derive generalized descent equations which contain both the consistent and covariant gravitational anomalies. The derivation makes use of the natural field reparametrizations which occur in the process of gauging the (anti) BRST symmetry and it leads to an expression for the covariant anomaly which satisfies strong covariance conditions. (orig.).

Ader, J.P.; Noirot, Y. (Bordeaux-1 Univ., 33 - Gradignan (France). Lab. de Physique Theorique); Gieres, F. (European Organization for Nuclear Research, Geneva (Switzerland). Theory Div.)

1991-03-14

2

Gauge and gravitational anomalies and Hawking radiation of rotating BTZ black holes  

Energy Technology Data Exchange (ETDEWEB)

In this paper we obtain the flux of Hawking radiation from rotating BTZ black holes from the gauge and gravitational anomalies point of view. Then we show that the gauge and gravitational anomaly in BTZ spacetime is cancelled by the total flux of a 2-dimensional blackbody at the Hawking temperature of the spacetime. (orig.)

Setare, M.R. [Payame Noor University, Department of Science, Bijar (Iran)

2007-02-15

3

Gravitational F-terms of SO/Sp gauge theories and anomalies  

International Nuclear Information System (INIS)

We study the first non trivial gravitational corrections to the F-terms of N = 1 SYM SO/Sp gauge theories, with matter in some representations, by using the generalized Konishi anomaly method. We derive equations at genus one for the operators in the chiral ring and compare them with the loop equations of the corresponding matrix models, finding agreement. We find that for adjoint representation the genus 0 contributions to such corrections can be adsorbed by a field redefinition; remarkably, this is not the case for matter in the (anti-)symmetric representation of (Sp) SO. (author)

2003-01-01

4

Hawking radiation from rotating black holes in anti-de Sitter spaces via gauge and gravitational anomalies  

CERN Document Server

Robinson-Wilczek's recent work, which treats Hawking radiation as a compensating flux to cancel gravitational anomaly at the horizon of a Schwarzschild-type black hole, is extended to study Hawking radiation of rotating black holes in anti-de Sitter spaces, especially that in dragging coordinate system, via gauge and gravitational anomalies. The results show that in order to restore gauge invariance and general coordinate covariance at the quantum level in the effective field theory, the charge and energy flux by requiring to cancel gauge and gravitational anomalies at the horizon, must have a form equivalent to that of a $(1+1)$-dimensional blackbody radiation at Hawking temperature with an appropriate chemical potential

Jiang, Q Q; Jiang, Qing-Quan; Wu, Shuang-Qing

2007-01-01

5

Hawking radiation from rotating black holes in anti-de Sitter spaces via gauge and gravitational anomalies  

Energy Technology Data Exchange (ETDEWEB)

Robinson-Wilczek's recent work, which treats Hawking radiation as a compensating flux to cancel gravitational anomaly at the horizon of a Schwarzschild-type black hole, is extended to study Hawking radiation of rotating black holes in anti-de Sitter spaces, especially that in dragging coordinate system, via gauge and gravitational anomalies. The results show that in order to restore gauge invariance and general coordinate covariance at the quantum level in the effective field theory, the charge and energy flux by requiring to cancel gauge and gravitational anomalies at the horizon, must have a form equivalent to that of a (1+1)-dimensional blackbody radiation at Hawking temperature with an appropriate chemical potential.

Jiang Qingquan [Institute of Particle Physics, Central China Normal University, Wuhan, Hubei 430079 (China)]. E-mail: jiangqingqua@126.com; Wu Shuangqing [College of Physical Science and Technology, Central China Normal University, Wuhan, Hubei 430079 (China)]. E-mail: sqwu@phy.ccnu.edu.cn

2007-04-05

6

Hawking radiation from rotating black holes in anti-de Sitter spaces via gauge and gravitational anomalies  

International Nuclear Information System (INIS)

Robinson-Wilczek's recent work, which treats Hawking radiation as a compensating flux to cancel gravitational anomaly at the horizon of a Schwarzschild-type black hole, is extended to study Hawking radiation of rotating black holes in anti-de Sitter spaces, especially that in dragging coordinate system, via gauge and gravitational anomalies. The results show that in order to restore gauge invariance and general coordinate covariance at the quantum level in the effective field theory, the charge and energy flux by requiring to cancel gauge and gravitational anomalies at the horizon, must have a form equivalent to that of a (1+1)-dimensional blackbody radiation at Hawking temperature with an appropriate chemical potential.

2007-04-05

7

Gravitational Anomaly and Transport  

CERN Document Server

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.

Landsteiner, Karl; Pena-Benitez, Francisco

2011-01-01

8

Hawking radiation from charged black holes via gauge and gravitational anomalies.  

Science.gov (United States)

Extending the method of Robinson and Wolczek, we show that in order to avoid a breakdown of general covariance and gauge invariance at the quantum level the total flux of charge and energy in each outgoing partial wave of a charged quantum field in a Reissner-Nordström black hole background must be equal to that of a (1 + 1)-dimensional blackbody at the Hawking temperature with the appropriate chemical potential. PMID:16712145

Iso, Satoshi; Umetsu, Hiroshi; Wilczek, Frank

2006-04-19

9

Hawking Radiation from Charged Black Holes via Gauge and Gravitational Anomalies  

International Nuclear Information System (INIS)

Extending the method of Robinson and Wolczek, we show that in order to avoid a breakdown of general covariance and gauge invariance at the quantum level the total flux of charge and energy in each outgoing partial wave of a charged quantum field in a Reissner-Nordstroem black hole background must be equal to that of a (1+1)-dimensional blackbody at the Hawking temperature with the appropriate chemical potential.

2006-04-21

10

Holographic gravitational anomalies  

International Nuclear Information System (INIS)

In the AdS/CFT correspondence one encounters theories that are not invariant under diffeomorphisms. In the boundary theory this is a gravitational anomaly, and can arise in 4k+2 dimensions. In the bulk, there can be gravitational Chern-Simons terms which vary by a total derivative. We work out the holographic stress tensor for such theories, and demonstrate agreement between the bulk and boundary. Anomalies lead to novel effects, such as a nonzero angular momentum for global AdS3. In string theory such Chern-Simons terms are known with exact coefficients. The resulting anomalies, combined with symmetries, imply corrections to the Bekenstein-Hawking entropy of black holes that agree exactly with the microscopic counting.

2006-01-01

11

Holographic gravitational anomalies  

Energy Technology Data Exchange (ETDEWEB)

In the AdS/CFT correspondence one encounters theories that are not invariant under diffeomorphisms. In the boundary theory this is a gravitational anomaly, and can arise in 4k+2 dimensions. In the bulk, there can be gravitational Chern-Simons terms which vary by a total derivative. We work out the holographic stress tensor for such theories, and demonstrate agreement between the bulk and boundary. Anomalies lead to novel effects, such as a nonzero angular momentum for global AdS{sub 3}. In string theory such Chern-Simons terms are known with exact coefficients. The resulting anomalies, combined with symmetries, imply corrections to the Bekenstein-Hawking entropy of black holes that agree exactly with the microscopic counting.

Kraus, Per [Department of Physics and Astronomy, UCLA, Los Angeles, CA 90095-1547 (United States); Larsen, Finn [Michigan Center for Theoretical Physics, Department of Physics, University of Michigan, Ann Arbor, MI 48109-1120 (United States)

2006-01-15

12

Gravitational Anomaly and Hydrodynamics  

CERN Multimedia

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.

Landsteiner, Karl; Melgar, Luis; Pena-Benitez, Francisco

2011-01-01

13

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.

2012-02-08

14

Gauge Group of gravity, spinors, and anomalies  

Energy Technology Data Exchange (ETDEWEB)

A discussion is given of the gravitational anomalies that arise from coupling Weyl spinors to gravity, treating the metric, the soldering form, and the connection as independent dynamical variables. This system is strictly analogous to Weyl spinors coupled to Yang-Mills fields and a nonlinear sigma model. The larger gauge group of this formulation is seen to lie at the root of the equivalence between Einstein and Lorentz anomalies.

Percacci, R.

1986-05-01

15

Holographic Gravitational Anomaly in First and Second Order Hydrodynamics  

CERN Document Server

We compute, in the framework of the fluid/gravity correspondence, the transport coefficients of a relativistic fluid affected by chiral and gauge-gravitational anomalies, including external electromagnetic fields. The computation is performed at first and second order in the hydrodynamical expansion. We use a 5-dim holographic model with pure gauge and mixed gauge-gravitational Chern-Simons terms in the action. We reproduce at first order previous results on the anomaly induced current of a magnetic field and a vortex in a relativistic fluid, and compute at second order the anomalous and non anomalous transport coefficients by using a Weyl covariant formalism. We find a dissipative and anomalous correction to the chiral magnetic conductivity due to the time dependence of the magnetic field. We also find a new contribution from the mixed gauge-gravitational anomaly to the shear waves dispersion relation. The role played by the chiral and gravitational anomalies in other transport coefficients is discussed.

Megias, Eugenio

2013-01-01

16

Covariant Approach of the Dynamics of Particles in External Gauge Fields, Killing Tensors and Quantum Gravitational Anomalies  

Directory of Open Access Journals (Sweden)

Full Text Available We give an overview of the first integrals of motion of particles in the presence of external gauge fields in a covariant Hamiltonian approach. The special role of Stäckel-Killing and Killing-Yano tensors is pointed out. Some nontrivial examples involving Runge-Lenz type conserved quantities are explicitly worked out. A condition of the electromagnetic field to maintain the hidden symmetry of the system is stated. A concrete realization of this condition is given by the Killing-Maxwell system and exemplified with the Kerr metric. Quantum symmetry operators for the Klein-Gordon and Dirac equations are constructed from Killing tensors. The transfer of the classical conserved quantities to the quantum mechanical level is analyzed in connection with quantum anomalies.

Mihai Visinescu

2011-01-01

17

Thermodynamics, gravitational anomalies and cones  

CERN Multimedia

By studying the Euclidean partition function on a cone, we argue that pure and mixed gravitational anomalies generate a "Casimir momentum" which manifests itself as parity violating coefficients in the hydrodynamic stress tensor and charge current. The coefficients generated by these anomalies enter at a lower order in the hydrodynamic gradient expansion than would be naively expected. In 1+1 dimensions, the gravitational anomaly affects coefficients at zeroth order in the gradient expansion. The mixed anomaly in 3+1 dimensions controls the value of coefficients at first order in the gradient expansion.

Jensen, Kristan; Yarom, Amos

2012-01-01

18

Holographic Gravitational Anomaly and Chiral Vortical Effect  

CERN Document Server

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...

Landsteiner, Karl; Melgar, Luis; Pena-Benitez, Francisco

2011-01-01

19

Gravitation and Gauge Symmetries  

CERN Multimedia

The purpose of this book (I quote verbatim from the back cover) is to 'shed light upon the intrinsic structure of gravity and the principle of gauge invariance, which may lead to a consistent unified field theory', a very laudable aim. The content divides fairly clearly into four sections (and origins). After a brief introduction, chapters 2-6 review the 'Structure of gravity as a theory based on spacetime gauge symmetries'. This is fairly straightforward material, apparently based on a one-semester graduate course taught at the University of Belgrade for about two decades, and, by implication, this is a reasonably accurate description of its level and assumed knowledge. There follow two chapters of new material entitled 'Gravity in flat spacetime' and 'Nonlinear effects in gravity'. The final three chapters, entitled 'Supersymmetry and supergravity', 'Kaluza-Klein theory' and 'String theory' have been used for the basis of a one-semester graduate course on the unification of fundamental interactions. The boo...

Stewart, J

2002-01-01

20

Chiral and Gravitational Anomalies on Fermi Surfaces  

CERN Document Server

A Fermi surface threaded by a Berry phase can be described by the Wess-Zumino-Witten (WZW) term. After gauging, it produces a five-dimensional Chern-Simons term in the action. We show how this Chern-Simons term captures the essence of the Abelian, non-Abelian, and mixed gravitational anomalies in describing both in- and off-equilibrium phenomena. In particular we derive a novel contribution to the Chiral Vortical Effect that arises when a temperature gradient is present. We also discuss the issue of universality of the anomalous currents.

Basar, Gokce; Zahed, Ismail

2013-01-01

 
 
 
 
21

Geometric phases and gravitational anomalies  

International Nuclear Information System (INIS)

[en] An analysis is made of the motion of a quantum particle in a gravitational field, and it is shown that a geometric phase arises under certain conditions. The connection of this results with the emergence of gravitational anomalies is described. (author)[pt] Analisa-se o movimento de uma particula quantica num campo gravitacional e mostra-se o aparecimento, sob certas condicoes, de uma fase geometrica. Descreve-se a conexao desse resultado com o aparecimento de anomalias gravitacionais. (M.W.O.)

1988-01-01

22

Review on possible gravitational anomalies  

CERN Multimedia

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).

Amador, X E

2005-01-01

23

Quantum Gravitational Contributions to Gauge Field Theories  

CERN Multimedia

We revisit quantum gravitational contributions to quantum gauge field theories in the gauge condition independent Vilkovisky-DeWitt formalism based on the background field method. With the advantage of Landau-DeWitt gauge, we explicitly obtain the gauge condition independent result for the quadratically divergent gravitational corrections to gauge couplings within any regularization schemes that can preserve both gauge invariance and original divergent behavior of integrals. The regularization scheme dependence is clarified by comparing with the results obtained by other methods. Unlike all the previous observations, we find that the resulting $\\beta$ function from gravitational contributions is power-law running but not asymptotic free.

Tang, Yong

2010-01-01

24

Gauge invariant gravitation theory. 1. Gravitational field source and spin  

International Nuclear Information System (INIS)

[en] 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

1988-01-01

25

Supercurrent anomaly in a supersymmetric gauge theory  

International Nuclear Information System (INIS)

It is demonstrated that an anomaly exists for the divergence of the supercurrent in a supersymmetric non-Abelian gauge theory. Since no gauge particle is coupled to the current, the anomaly does not alter the renormalizability of the theory. Some consequences of the anomaly are discussed

1977-11-15

26

Hawking radiation via higher-spin gauge anomalies  

International Nuclear Information System (INIS)

We give a higher-spin generalization of the anomaly method for the Hawking radiation from black holes. In the paper [S. Iso, T. Morita, and H. Umetsu, arXiv:0710.0453.] higher-spin generalizations of the gauge (and gravitational) anomalies in d=2 were obtained. By applying these anomalies to black hole physics, we derive the higher moments of the Hawking fluxes. We also give a higher-spin generalization of the trace anomaly method by Christensen and Fulling [S. Christensen and S. Fulling, Phys. Rev. D 15, 2088 (1977).

2008-02-15

27

Geometrical gauge approach for electromagnetism and gravitation  

Science.gov (United States)

A gauge model for gravitation coupled to Maxwell theory is examined. By considering the Lorentz and U (1) groups in a bundle of linear frames, the Maxwell equations and Yang's gravitational equation are derived. The approach has a gauge-like lagrangian for the sourceless case, which leads to the field equations. Present address: Departamento de Fisica, Universidade Federal do Parana, Caixa Postal 19081, 80.000 Curitiba PR, Brazil.

Stedile, E.

1986-11-01

28

Gauge independence of the local trace anomaly of vectors and antisymmetric tensor fields  

International Nuclear Information System (INIS)

[en] We show that in the path-integral formalism the local trace anomalies of vector fields in d = 4 and antisymmetric tensor fields in d = 6, coupled to an external gravitational field, are gauge independent if one uses the background-covariant gauge-fixing term -(2?)/sup -1/ (D/sub ?//sub =/A/sup ?//sup >1/...?/sub d/2/)2. Hence, we disagree with recent claims in the literature that the local trace anomaly is gauge dependent

1988-11-15

29

Singlet deflected anomaly/gauge mediation  

Science.gov (United States)

We study an extension of the standard anomaly/gauge mediation scenario where the messenger fields have direct interactions with an extra gauge singlet. This realizes a phenomenologically viable NMSSM-like scenario free of the ?-b problem. Current cosmological constraints imply a small size for the anomaly-mediation contributions, unless some source of R-parity violation is permitted. In the latter case the allowed regions in the parameter space can be substantially larger than in the corresponding gauge-mediation scenario.

de Blas, J.; Delgado, A.

2012-02-01

30

Singlet deflected anomaly/gauge mediation  

CERN Multimedia

We study an extension of the standard anomaly/gauge mediation scenario where the messenger fields have direct interactions with an extra gauge singlet. This realizes a phenomenologically viable NMSSM-like scenario free of the mu-b_mu problem. Current cosmological constraints imply a small size for the anomaly-mediation contributions, unless some source of R-parity violation is permitted. In the latter case the allowed regions in the parameter space can be substantially larger than in the corresponding gauge-mediation scenario.

de Blas, J

2011-01-01

31

Gravitational Anomalies and Thermal Hall effect in Topological Insulators  

CERN Multimedia

It has been suggested that a temperature gradient will induce a Leduc-Righi, or thermal Hall, current in the Majorana quasiparticles localized on the surface of class DIII topological insulators, and that the magnitude of this current can be related {\\it via} an Einstein argument to a Hall-like energy flux induced by gravity. We critically examine this idea, and argue that the gravitational Hall effect is more complicated than its familiar analogue. A conventional Hall current is generated by a {\\it uniform} electric field, but computing the flux from the gravitational Chern-Simons functional shows that gravitational field {\\it gradients} - i.e. tidal forces - are needed to induce a energy-momentum flow. We relate the surface energy-momentum flux to a domain-wall gravitational anomaly {\\it via} the Callan-Harvey inflow mechanism. We stress that the gauge invariance of the combined bulk-plus-boundary theory ensures that the current in the domain wall always experiences a "covariant" rather than "consistent" an...

Stone, Michael

2012-01-01

32

Gravitational anomalies: a recipe for Hawking radiation  

CERN Multimedia

We explore the method of Robinson and Wilczek for deriving the Hawking temperature of a black hole. In this method, the Hawking radiation restores general covariance in an effective theory of near-horizon physics which otherwise exhibits a gravitational anomaly at the quantum level. The method has been shown to work for broad classes of black holes in arbitrary spacetime dimensions. These include static black holes, accreting or evaporating black holes, charged black holes, rotating black holes, and even black rings. In the charged and rotating cases, the expected super-radiant current is also reproduced.

Das, Saurya; Vagenas, Elias C

2007-01-01

33

Extended Holomorphic Anomaly in Gauge Theory  

CERN Document Server

The partition function of an N=2 gauge theory in the Omega-background satisfies, for generic value of the parameter beta=-eps_1/eps_2, the, in general extended, but otherwise beta-independent, holomorphic anomaly equation of special geometry. Modularity together with the (beta-dependent) gap structure at the various singular loci in the moduli space completely fixes the holomorphic ambiguity, also when the extension is non-trivial. In some cases, the theory at the orbifold radius, corresponding to beta=2, can be identified with an "orientifold" of the theory at beta=1. The various connections give hints for embedding the structure into the topological string.

Krefl, Daniel; 10.1007/s11005-010-0432-2

2011-01-01

34

Anomaly Nucleation Constrains SU(2) Gauge Theories  

CERN Multimedia

We argue for the existence of additional constraints on SU(2) gauge theories in four dimensions when realized in ultraviolet completions admitting an analog of D-brane nucleation. In type II string compactifications these constraints are necessary and sufficient for the absence of cubic non-abelian anomalies in certain nucleated SU(N>2) theories. It is argued that they appear quite broadly in the string landscape. Implications for particle physics are discussed; most realizations of the standard model in this context are inconsistent, unless extra electroweak fermions are added.

Halverson, James

2013-01-01

35

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.

1988-01-01

36

Gravitational Contributions to the Running of Gauge Couplings  

CERN Document Server

Gravitational contributions to the running of gauge couplings are calculated by using different regularization schemes. As the $\\beta$ function concerns counter-terms of dimension four, only quadratical divergencies from the gravitational contributions need to be investigated. A consistent result is obtained by a regularization scheme which can appropriately treat the quadratical divergencies and preserve non-abelian gauge symmetry. The harmonic gauge condition for gravity is used in both diagrammatical and background field calculations, the resulting gravitational corrections to the $\\beta$ function are found to be nonzero and regularization scheme independent.

Tang, Yong

2008-01-01

37

Parity anomalies in gauge theories in 2 + 1 dimensions  

International Nuclear Information System (INIS)

We show that the introduction of massless fermions in an abelian gauge theory in 2+1 dimensions does not lead to any parity anomaly despite a non-commutativity of limits in the structure function of the odd part of the vacuum polarization tensor. However, parity anomaly does exist in non-abelian theories due to a conflict between gauge invariance under large gauge transformations and the parity symmetry. 6 refs.

1986-01-01

38

Higher-spin gauge and trace anomalies in two-dimensional backgrounds  

International Nuclear Information System (INIS)

Two-dimensional quantum fields in electric and gravitational backgrounds can be described by conformal field theories, and hence all the physical (covariant) quantities can be written in terms of the corresponding holomorphic quantities. In this paper, we first derive relations between covariant and holomorphic forms of higher-spin currents in these backgrounds, and then, by using these relations, obtain higher-spin generalizations of the trace and gauge (or gravitational) anomalies up to spin 4. These results are applied to derive higher-moments of Hawking fluxes in black holes in a separate paper [S. Iso, T. Morita, H. Umetsu, Hawking radiation via higher-spin gauge anomalies, (arXiv: 0710.0456 [hep-th])

2008-08-11

39

Higher-spin gauge and trace anomalies in two-dimensional backgrounds  

Energy Technology Data Exchange (ETDEWEB)

Two-dimensional quantum fields in electric and gravitational backgrounds can be described by conformal field theories, and hence all the physical (covariant) quantities can be written in terms of the corresponding holomorphic quantities. In this paper, we first derive relations between covariant and holomorphic forms of higher-spin currents in these backgrounds, and then, by using these relations, obtain higher-spin generalizations of the trace and gauge (or gravitational) anomalies up to spin 4. These results are applied to derive higher-moments of Hawking fluxes in black holes in a separate paper [S. Iso, T. Morita, H. Umetsu, Hawking radiation via higher-spin gauge anomalies, (arXiv: 0710.0456 [hep-th])].

Iso, Satoshi [Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), Oho 1-1, Tsukuba, Ibaraki 305-0801 (Japan)], E-mail: satoshi.iso@kek.jp; Morita, Takeshi [Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502 (Japan)], E-mail: mtakeshi@yukawa.kyoto-u.ac.jp; Umetsu, Hiroshi [Okayama Institute for Quantum Physics, Kyoyama 1-9-1, Okayama 700-0015 (Japan)], E-mail: hiroshi_umetsu@pref.okayama.jp

2008-08-11

40

Notes on gauge theory and gravitation  

International Nuclear Information System (INIS)

[en] 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.)

1981-01-01

 
 
 
 
41

Probing the gravitational scale via running gauge couplings  

International Nuclear Information System (INIS)

[en] According to a recent paper by Robinson and Wilczek, the leading gravitational corrections to the running of gauge couplings tend to reduce the values of the couplings at energies below the gravitational scale, defined to be the energy above which gravity becomes strongly interacting. If the physical gravitational scale is sufficiently low, as conjectured in certain extra-dimension models, this behavior of the gauge couplings can be measured in future high energy experiments, providing a way to determine where the gravitational scale lies. We estimate that measurements of the fine structure constant at the Large Hadron Collider and the proposed International Linear Collider energies can probe the gravitational scale up to several hundred TeV, which will be the most stringent test that can be obtained in the conceivable future

2007-02-22

42

Topology and heterotic, gravitational, Lorentz and super-Weyl anomalies  

International Nuclear Information System (INIS)

[en] The (1,0) superdiffeomorphic and Lorentz anomalies are constructed using cohomology and descent equations in heterotic superspace. The superfield gravitational Wess-Zumino term is presented. Supergraph techniques are used to calculate the coefficients of the superdiffeomorphic, Lorentz and super-Weyl anomalies. (orig.)

1988-08-29

43

Finite Action in d5 Gauged Supergravity and Dilatonic Conformal Anomaly for Dual Quantum Field Theory  

CERN Multimedia

Gauged supergravity (SG) with single scalar (dilaton) and arbitrary scalar potential is considered. Such dilatonic gravity describes special RG flows in extended SG where scalars lie in one-dimensional submanifold of total space. The surface counterterm and finite action for such gauged SG in three-, four- and five-dimensional asymptotically AdS space are derived. Using finite action and consistent gravitational stress tensor (local surface counterterm prescription) the regularized expressions for free energy, entropy and mass of d4 dilatonic AdS black hole are found. The same calculation is done within standard reference background subtraction. The dilaton-dependent conformal anomaly from d3 and d5 gauged SGs is calculated using AdS/CFT correspondence. Such anomaly should correspond to two- and four-dimensional dual quantum field theory with broken conformal invariance, respectively. The candidate c-functions for d3 and d5 SGs are suggested. Their numerical investigation for particular example of exponential...

Nojiri, S; Ogushi, S; Nojiri, Shin'ichi; Odintsov, Sergei D.; Ogushi, Sachiko

2000-01-01

44

Hawking radiation from rotating black holes and gravitational anomalies  

International Nuclear Information System (INIS)

We study the Hawking radiation from Rotating black holes from the gravitational anomalies point of view. First, we show that the scalar field theory near the Kerr black hole horizon can be reduced to the 2-dimensional effective theory. Then, following Robinson and Wilczek, we derive the Hawking flux by requiring the cancellation of gravitational anomalies. We also apply this method to Hawking radiation from higher dimensional Myers-Perry black holes. In the appendix, we present the trace anomaly derivation of Hawking radiation to argue the validity of the boundary condition at the horizon.

2006-08-15

45

Two-time physics with gravitational and gauge field backgrounds  

International Nuclear Information System (INIS)

It is shown that all possible gravitational, gauge and other interactions experienced by particles in ordinary d dimensions (one time) can be described in the language of two-time physics in a spacetime with d+2 dimensions. This is obtained by generalizing the world line formulation of two-time physics by including background fields. A given two-time model, with a fixed set of background fields, can be gauged fixed from d+2 dimensions to (d-1)+1 dimensions to produce diverse one-time dynamical models, all of which are dually related to each other under the underlying gauge symmetry of the unified two-time theory. To satisfy the gauge symmetry of the two-time theory the background fields must obey certain coupled differential equations that are generally covariant and gauge invariant in the target (d+2)-dimensional spacetime. The gravitational background obeys a closed homothety condition while the gauge field obeys a differential equation that generalizes a similar equation derived by Dirac in 1936. Explicit solutions to these coupled equations show that the usual gravitational, gauge, and other interactions in d dimensions may be viewed as embedded in the higher (d+2)-dimensional space, thus displaying higher spacetime symmetries that otherwise remain hidden.

2000-10-15

46

Gauge Problem in the Gravitational Self-Force I. Harmonic Gauge Approach in the Schwarzschild Background  

CERN Multimedia

The metric perturbation induced by a particle in the Schwarzschild background is usually calculated in the Regge-Wheeler (RW) gauge, whereas the gravitational self-force is known to be given by the tail part of the metric perturbation in the harmonic gauge. Thus, to identify the gravitational self-force correctly in a specified gauge, it is necessary to find out a gauge transformation that connects these two gauges. This is called the gauge problem. As a direct approach to solve the gauge problem, we formulate a method to calculate the metric perturbation in the harmonic gauge on the Schwarzshild backgound. We apply the Fourier-harmonic expansion to the metric perturbation and reduce the problem to the gauge transformation of the Fourier-harmonic coefficients (radial functions) from the RW gauge to the harmonic gauge. We derive a set of decoupled radial equations for the gauge transformation. These equations are found to have a simple second-order form for the odd parity part and the forms of spin $s=0$ and 1...

Sago, N; Sasaki, M; Sago, Norichika; Nakano, Hiroyuki; Sasaki, Misao

2003-01-01

47

Gauge problem in the gravitational self-force: Harmonic gauge approach in the Schwarzschild background  

International Nuclear Information System (INIS)

The metric perturbation induced by a particle in the Schwarzschild background is usually calculated in the Regge-Wheeler (RW) gauge, whereas the gravitational self-force is known to be given by the tail part of the metric perturbation in the harmonic gauge. Thus, to identify the gravitational self-force correctly in a specified gauge, it is necessary to find out a gauge transformation that connects these two gauges. This is called the gauge problem. As a direct approach to solve the gauge problem, we formulate a method to calculate the metric perturbation in the harmonic gauge on the Schwarzschild background. We apply the Fourier-harmonic expansion to the metric perturbation and reduce the problem to the gauge transformation of the Fourier-harmonic coefficients (radial functions) from the RW gauge to the harmonic gauge. We derive a set of decoupled radial equations for the gauge transformation. These equations are found to have a simple second-order form for the odd parity part and the forms of spin s=0 and 1 Teukolsky equations for the even parity part. As a by-product, we correct typographical errors in Zerilli's paper and present a set of corrected equations in Appendix A

2003-05-15

48

Gauge-covariant bimetric theory of gravitation and electromagnetism  

Energy Technology Data Exchange (ETDEWEB)

The Weyl theory of gravitation and electromagnetism, as modified by Dirac, contains a gauge-covariant scalar ..beta.. which has no geometric significance. This is a flaw if one is looking for a geometric description of gravitation and electromagnetism. A bimetric formalism is therefore introduced which enables one to replace ..beta.. by a geometric quantity. The formalism can be simplified by the use of a gauge-invariant physical metric. The resulting theory agrees with the general relativity for phenomena in the solar system.

Israelit, M.; Rosen, N.

1983-10-01

49

More on counterterms in the gravitational action and anomalies  

CERN Multimedia

The addition of boundary counterterms to the gravitational action ofasymptotically anti-de Sitter spacetimes permits us to define the partitionfunction unambiguously without background subtraction. We show that theinclusion of p-form fields in the gravitational action requires the addition offurther counterterms which we explicitly identify. We also relate logarithmicdivergences in the action dependent on the matter fields to anomalies in thedual conformal field theories. In particular we find that the anomaly predictedfor the correlator of the stress energy tensor and two vector currents in fourdimensions agrees with that of the ${\\cal{N}} = 4$ superconformal SU(N) gaugetheory.

Taylor-Robinson, M M

2000-01-01

50

Enlarged gauge symmetry of gravitation theory  

Energy Technology Data Exchange (ETDEWEB)

The gauge group of the general theory of relativity is extended to local GL(4,R). The purpose of this extension is to provide the freedom for regularizing the operators which occur upon quantizing the theory. Under certain natural requirements the extension is shown to be essentially unique.

Komar, A.

1984-07-15

51

Gravitational anomalies, gerbes and hamiltonian quantization  

CERN Document Server

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.

Ekstrand, C

2000-01-01

52

Axial anomaly in supersymmetry gauge theories  

Energy Technology Data Exchange (ETDEWEB)

An explicit relationship between the axial-current operator, which satisfies the Adler-Bardeen theorem, and the axial supersymmetric current, which appears in the supercurrent, is found. The axial and superconformal anomalies are mutually consistent in all orders of perturbation theory.

Kazakov, D.I.

1985-03-25

53

Anomaly-free left-right-symmetric models with gauged baryon and lepton numbers  

Energy Technology Data Exchange (ETDEWEB)

A left-right-symmetric extension of the standard electroweak interaction model is presented in which baryon- ({ital B}-) and lepton- ({ital scrL}-) number conservation are considered as spontaneously broken gauge symmetries. The gauge, global, and the mixed gauge-gravitational anomalies in the model are canceled by invoking new fermion matter that carries baryon as well as lepton numbers. We find a class of models in which the exotic fermions carry the same electric charges as the {ital N} families of conventional fermions but different {ital B} and {ital scrL} charges. The Higgs structure in this case allows a light massive neutral boson with a lower bound of 120 GeV.

He, X. (Research Centre for High Energy Physics, School of Physics, University of Melbourne, Parkville, Victoria 3052, Australia (AU)); Rajpoot, S. (Department of Physics, University of California, Riverside, California 92521 (USA))

1990-03-01

54

Algebraic characterization of gauge anomalies on a nontrivial bundle  

Science.gov (United States)

We discuss the algebraic way of solving the descent equations corresponding to the BRST consistency condition for the gauge anomalies and the Chern-Simons terms on a nontrivial bundle. The method of decomposing the exterior space-time derivative as a BRST commutator is extended to the present case.

John, P.; Moritsch, O.; Schweda, M.; Sorella, S. P.

1998-09-01

55

Chiral gauge field and axial anomaly in a Weyl semimetal  

Science.gov (United States)

Weyl fermions are two-component chiral fermions in (3+1) dimensions. When coupled to a gauge field, the Weyl fermion is known to have an axial anomaly, which means the current conservation of the left-handed and right-handed Weyl fermions cannot be preserved separately. Recently, Weyl fermions have been proposed in condensed-matter systems named “Weyl semimetals.” In this paper we propose a Weyl semimetal phase in magnetically doped topological insulators, and study the axial anomaly in this system. We propose that the magnetic fluctuation in this system plays the role of a “chiral gauge field” which minimally couples to the Weyl fermions with opposite charges for two chiralities. We study the anomaly equation of this system and discuss its physical consequences, including one-dimensional chiral modes in a ferromagnetic vortex line, and a novel plasmon-magnon coupling.

Liu, Chao-Xing; Ye, Peng; Qi, Xiao-Liang

2013-06-01

56

Cosmological constant and the gauge-covariant theory of gravitation  

Energy Technology Data Exchange (ETDEWEB)

The long-standing problem of cosmological constants arising from unified theories in particle physics, on the one side, and from purely gravitational phenomena, on the other side, is studied in the framework of the gauge-covariant theory of gravitation. The notion of system of units depending upon the corresponding interaction as well as the systematics provided by the GCTG could solve the problem. We may have zero Einstein cosmological constant but nonzero Linde-type cosmological constants. Both are related through a tansformation of units.

Cervero, J.; Estevez, P.G. (Salamanca Univ. (Spain). Dept. de Fisica Teorica)

1982-02-11

57

The Case for a Gravitational de Sitter Gauge Theory  

CERN Multimedia

With the exception of gravitation, the known fundamental interactions of Nature are mediated by gauge fields. A comparison of the candidate groups for a gauge theory possibly describing gravitation favours the Poincaré group as the obvious choice. This theory gives Einstein's equations in a particular case, and Newton's law in the static non-relativistic limit, being seemingly sound at the classical level. But it comes out that it is not quantizable. The usual procedure of adding counterterms to make it a consistent and renormalizable theory leads to two possible theories, one for each of the two de Sitter groups, SO(4,1) and SO(3,2). The consequences of changing from the Poincaré to the de Sitter group, as well as the positive aspects, perspectives and drawbacks of the resulting theory are discussed.

Aldrovandi, R

1995-01-01

58

On the gravitational origin of the Pioneer Anomaly  

CERN Document Server

From Doppler tracking data and data on circular motion of astronomical objects we obtain a metric of the Pioneer Anomaly. The metric resolves the issue of manifest absence of anomaly acceleration in orbits of the outer planets and extra-Pluto objects of the Solar system. However, it turns out that the energy-momentum tensor of matter, which generates such a gravitational field in GR, violates energy dominance conditions. At the same time the equation of state derived from the energy-momentum tensor is that of dark energy with $w=-1/3$. So the model proposed must be carefully studied by "Grand-Fit" investigations.

Siutsou, I A

2009-01-01

59

Spontaneous breakdown of the vacuum in the gauge-covariant theory of gravitation  

Energy Technology Data Exchange (ETDEWEB)

In the context of the gauge covariant theory of gravitation it is shown that, if one wishes to recover Einstein's equations to define the so-called gravitational units, there are, in the vacuum case, two possible gravitational gauges; nevertheless, they establish a different set of units, and, therefore, a degeneracy arises which has to be removed using physical assumptions.

Cervero, J.; Estevez, P.G. (Departamento de Fisica Teorica, Facultad de Ciencias, Salamanca (Spain))

1981-03-14

60

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.)

2009-01-01

 
 
 
 
61

Supersymmetry, quantum gauge anomalies and generalized Chern-Simons terms in chiral gauge theory  

Energy Technology Data Exchange (ETDEWEB)

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.)

Schmidt, Torsten

2009-05-13

62

Hawking radiation of a vector field and gravitational anomalies  

International Nuclear Information System (INIS)

Recently, the relation between Hawking radiation and gravitational anomalies has been used to estimate the flux of Hawking radiation for a large class of black objects. In this paper, we extend the formalism, originally proposed by Robinson and Wilczek, to the Hawking radiation of vector particles (photons). It is explicitly shown, with the Hamiltonian formalism, that the theory of an electromagnetic field on d-dimensional spherical black holes reduces to one of an infinite number of massive complex scalar fields on 2-dimensional spacetime, for which the usual anomaly-cancellation method is available. It is found that the total energy emitted from the horizon for the electromagnetic field is just (d-2) times that for a scalar field. The results support the picture that Hawking radiation can be regarded as an anomaly eliminator on horizons. Possible extensions and applications of the analysis are discussed.

2007-10-15

63

A Gauge-theoretical Treatment of the Gravitational Field: Classical  

CERN Document Server

In the geometrodynamical setting of general relativity one is concerned mainly with Riemannian metrics over a manifold $M$. We show that for the space Riem$(M)$, we have a natural principal fiber bundle (PFB) structure. This construction makes the gravitational field amenable to exactly the same gauge-theoretic treatment given in [Littlejohn] where it is used to separate rotational and vibrational degrees of freedom of $n$-particle systems, both classically and quantum mechanically. Furthermore, we show how the gauge connection in this PFB setting can be seen as a realization of Mach's Principle of Relative Motion, in accordance with Barbour's et al work on timeless gravitational theories. We show Barbour's reconstruction of GR is obtained by requiring the connection to be the one induced by the deWitt metric in Riem$(M)$. As a simple application of the gauge theory, we put the ADM lagrangian in a Kaluza-Klein context, and from conservation of charge we derive an interesting condition on the three-dimensional...

Gomes, Henrique

2008-01-01

64

The approximate solution with torsion for a charged particle in a gauge theory of gravitation  

International Nuclear Information System (INIS)

In this paper a method of finding an approximate solution of field equations in a gauge theory of gravitation is given by means of physical considerations. Using this method, an approximate solution of the field of a charged particle in a gauge theory of gravitation, a space-time metric and torsion tensors, is obtained. This method can also be used to solve field equations in other gauge theories of gravitation. (author).

1981-01-01

65

Lorentz anomaly in semi-light-cone gauge superstrings  

International Nuclear Information System (INIS)

We study the Lorentz invariance of D=4 and 6 superstrings in the double-spinor formalism, which are equivalent to the D=4 and 6 superstrings in the pure-spinor formalism in the sense of the BRST cohomology. We first re-examine how the conformal and Lorentz anomalies appear in the D=4 and 6 Green-Schwarz superstrings in the semi-light-cone gauge in the framework of BRST quantization. We construct a set of BRST invariant Lorentz generators and show that they do not form a closed algebra, even cohomologically. We then turn to the construction of Lorentz generators in the D=4 and 6 double-spinor superstrings, and show that the Lorentz invariance is again anomalous. We also discuss the relation between the anomaly-free Lorentz generators in the lower-dimensional pure-spinor formalisms and that obtained in this paper. (author)

2007-01-01

66

Hawking Radiation and Covariant Anomalies  

CERN Multimedia

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.

Banerjee, Rabin

2007-01-01

67

On Gravitational Dressing of 2D Field Theories in Chiral Gauge  

UK PubMed Central (United Kingdom)

After giving a pedagogical review of the chiral gauge approach to 2D gravity, with particularemphasis on the derivation of the gravitational Ward identities, we discuss in some detail theinterpretation of matter correlation functions coupled to gravity in chiral gauge. We argue thatin chiral gauge no explicit gravitational dressing factor, analogue to the Liouville exponentialin conformal gauge, is necessary for left-right symmetric matter operators. In particular, weexamine the gravitationally dressed four-point correlation function of products of left and rightfermions. We solve the corresponding gravitational Ward identity exactly: in the presence ofgravity this four-point function exhibits a logarithmic short-distance singularity, instead of thepower-law singularity in the absence of gravity. This rather surprising effect is non-perturbativein the gravitational coupling and is a sign for logarithms in the gravitationally dressed operatorproduct expansions. We also discuss...

Adel Bilal; Ian I. Kogan

68

Covariant and consistent anomalies in even-dimensional chiral gauge theories  

Energy Technology Data Exchange (ETDEWEB)

This paper is devoted to various aspects of anomalies in even-dimensional chiral gauge theories. The difference between the covariant and consistent anomalies is carefully explained in terms of their different origins. The consistent current is defined in terms of a gauge-variant effective action constructed from the covariant current. An alternative scheme is set up where the covariant anomaly is unaltered but the consistent anomaly vanishes because the effective action is gauge-invariant. A discussion of theories with vector and axial currents separately gauged is included: here, apart from the covariant anomalies, two different ways of constructing gauge-variant effective actions are possible, giving rise to different structures of the consistent anomalies.

Banerjee, H.; Banerjee, R.; Mitra, P.

1986-10-01

69

Gauge-invariant Hamiltonian dynamics of cylindrical gravitational waves  

CERN Multimedia

The model of cylindrical gravitational waves is employed to work out and check a recent proposal in Ref. [11] how a diffeomorphism-invariant Hamiltonian dynamics is to be constructed. The starting point is the action by Ashtekar and Pierri because it contains the boundary term that makes it differentiable for non-trivial variations at infinity. With the help of parametrization at infinity, the notion of gauge transformation is clearly separated from that of asymptotic symmetry. The symplectic geometry of asymptotic symmetries and asymptotic time is described and the role of the asymptotic structures in defining a zero-motion frame for the Hamiltonian dynamics of Dirac observables is explained. Complete sets of Dirac observables associated with the asymptotic fields are found and the action of the asymptotic symmetries on them is calculated. The construction of the corresponding quantum theory is sketched: the Fock space, operators of asymptotic fields, the Hamiltonian and the scattering matrix are determined.

Kouletsis, I; Bicák, J; Kouletsis, Ioannis; Hajicek, Petr; Bicak, Jiri

2003-01-01

70

Anomalies in noncommutative gauge theories, Seiberg-Witten transformation and Ramond-Ramond couplings  

CERN Document Server

We propose an exact expression for the unintegrated form of the star gauge invariant axial anomaly in an arbitrary even dimensional gauge theory. The proposal is based on the inverse Seiberg-Witten map and identities related to it, obtained earlier by comparing Ramond-Ramond couplings in different decsriptions. The integrated anomalies are expressed in terms of a simplified version of the Elliott formula involving the noncommutative Chern character. These anomalies, under the Seiberg-Witten transformation, reduce to the ordinary axial anomalies. Compatibility with existing results of anomalies in noncommutative theories is established.

Banerjee, R

2004-01-01

71

Conservation of Gravitational Energy-Momentum and Inner Diffeomorphism Group Gauge Invariance  

Directory of Open Access Journals (Sweden)

Full Text Available Viewing gravitational energy momentum as equal by observation, but different in essence from inertial energy-momentum requires two different symmetries to account for their independent conservations—spacetime and inner translation invariance. Gauging the latter a generalization of non-Abelian gauge theories of compact Lie groups is developed resulting in the gauge theory of the non-compact group of volume-preserving diffeomorphisms of an inner Minkowski space M4. As usual the gauging requires the introduction of a covariant derivative, a gauge field and a field strength operator. An invariant and minimal gauge field Lagrangian is derived. The classical field dynamics and the conservation laws for the new gauge theory are developed. Finally, the theory’s Hamiltonian in the axial gauge is expressed by two times six unconstrained independent canonical variables obeying the usual Poisson brackets and the positivity of the Hamiltonian is related to a condition on the support of the gauge fields.

Christian Wiesendanger

2013-01-01

72

Theory of a gauged gravitational field with localization of the Einstein group  

Energy Technology Data Exchange (ETDEWEB)

This paper formulates a theory of a gauged gravitational field with localization of the group of motions of a homogeneous static Einstein universe. A relationship is established between the Riemannian metric and the gauge fields of Einstein's group, starting from the tetradic components of Einstein's universe. It is shown that in the limit of infinite radius of curvature of Einstein's universe the given Einstein-invariant gauge theory transforms into the tetradic theory of gravitation with localized triadic rotations. The exact solutions are obtained in the form of nonsingular cosmological models.

Tunyak, V.N.

1986-01-01

73

Gravitational waves from Abelian gauge fields and cosmic strings at preheating  

International Nuclear Information System (INIS)

Primordial gravitational waves provide a very important stochastic background that could be detected soon with interferometric gravitational wave antennas or indirectly via the induced patterns in the polarization anisotropies of the cosmic microwave background. The detection of these waves will open a new window into the early Universe, and therefore it is important to characterize in detail all possible sources of primordial gravitational waves. In this paper we develop theoretical and numerical methods to study the production of gravitational waves from out-of-equilibrium gauge fields at preheating. We then consider models of preheating after hybrid inflation, where the symmetry breaking field is charged under a local U(1) symmetry. We analyze in detail the dynamics of the system in both momentum and configuration space. We show that gauge fields leave specific imprints in the resulting gravitational wave spectra, mainly through the appearance of new peaks at characteristic frequencies that are related to the mass scales in the problem. We also show how these new features in the spectra correlate with stringlike spatial configurations in both the Higgs and gauge fields that arise due to the appearance of topological winding numbers of the Higgs around Nielsen-Olesen strings. We study in detail the time evolution of the spectrum of gauge fields and gravitational waves as these strings evolve and decay before entering a turbulent regime where the gravitational wave energy density saturates.

2010-10-15

74

Commutator gauge anomaly, bundle of vacua and particle creation in two dimensions  

International Nuclear Information System (INIS)

We describe the physical situation in which the consideration of the fermionic vacuum bundle over gauge group manifold is useful. The bundle curvature turns out to be connected with the commutator gauge anomaly. This allows to consider the problem where this curvature is manifested. (author). 17 refs

1991-01-01

75

Axial and gauge anomalies in the field-antifield quantization of the generalized Schwinger model  

International Nuclear Information System (INIS)

[en] In the generalized Schwinger model the vector and axial vector currents are linearly coupled, with arbitrary coefficients, to the gauge connection. Therefore it represents an interesting example of a theory where both gauge anomalies and anomalous divergences of global currents show up in general. We derive results for these two kinds of quantum corrections inside the field-antifield framework. (author)

1999-01-15

76

Axial and gauge anomalies in the field-antifield quantization of the generalized Schwinger model  

Energy Technology Data Exchange (ETDEWEB)

In the generalized Schwinger model the vector and axial vector currents are linearly coupled, with arbitrary coefficients, to the gauge connection. Therefore it represents an interesting example of a theory where both gauge anomalies and anomalous divergences of global currents show up in general. We derive results for these two kinds of quantum corrections inside the field-antifield framework. (author)

Amorim, R.; Braga, N.R.F.; Thibes, R. [Instituto de Fisica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil)

1999-01-15

77

A possible general relativistic explanation for the gravitational anomalies during the solar eclipses.  

Science.gov (United States)

Measurements made during solar eclipses showed some gravitational anomalies: i) a displacement of the oscillation plane of the paraconic pendulum, Foucault pendulum and torsion pendulum; ii) a shift of the Newtonian gravitational field in Foucault pendulum-type experiments. Several assumptions have been made until now, such as: the Moon screening effect or a modified Newtonian force. The authors try to explain these anomalies in a general relativistic model using the Higgs mechanism of spontaneous symmetry breaking which modifies the gravitational index of refraction.

Agop, M.; Dariescu, C.; Dariescu, M.-A.; Griga, V.; Brinza, I.

78

Gravitational anomaly and Hawking radiation of apparent horizon in FRW universe  

Energy Technology Data Exchange (ETDEWEB)

Motivated by the successful applications of the anomaly cancellation method to derive Hawking radiation from various types of black hole spacetimes, we further extend the gravitational anomaly method to investigate the Hawking radiation from the apparent horizon of a FRW universe by assuming that the gravitational anomaly also exists near the apparent horizon of the FRW universe. The result shows that the radiation flux from the apparent horizon of the FRW universe measured by a Kodama observer is just the pure thermal flux. The result presented here will further confirm the thermal properties of the apparent horizon in a FRW universe. (orig.)

Li, Ran; Ren, Ji-Rong; Wei, Shao-Wen [Lanzhou University, Institute of Theoretical Physics, Lanzhou, Gansu (China)

2009-08-15

79

Gravitational anomaly and Hawking radiation of apparent horizon in FRW universe  

International Nuclear Information System (INIS)

Motivated by the successful applications of the anomaly cancellation method to derive Hawking radiation from various types of black hole spacetimes, we further extend the gravitational anomaly method to investigate the Hawking radiation from the apparent horizon of a FRW universe by assuming that the gravitational anomaly also exists near the apparent horizon of the FRW universe. The result shows that the radiation flux from the apparent horizon of the FRW universe measured by a Kodama observer is just the pure thermal flux. The result presented here will further confirm the thermal properties of the apparent horizon in a FRW universe. (orig.)

2009-01-01

80

One loop anomalies and Wess-Zumino terms for general gauge theories  

CERN Multimedia

One loop anomalies and their dependence on antifields for general gauge theories are investigated within a Pauli-Villars regularization scheme. For on-shell theories {\\it 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.

Gomis, J P; Pons, J M; Zamora, Frederic

1995-01-01

 
 
 
 
81

One-loop anomalies and Wess-Zumino terms for general gauge theories  

Energy Technology Data Exchange (ETDEWEB)

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.).

Gomis, J. [Kyoto Univ. (Japan). Research Inst. for Mathematical Sciences; Kamimura, K. [Department of Physics, Toho University, Funabashi 274 (Japan); Pons, J.M. [Center for Relativity, Department of Physics, University of Texas at Austin, Austin, 78712 TX (United States)]|[Departament d`Estructura i Constituents de la Materia, Universitat de Barcelona and Institut de Fisica d`Altes Energies, Diagonal, 647, E-08028 Barcelona (Spain); Zamora, F. [Departament d`Estructura i Constituents de la Materia, Universitat de Barcelona and Institut de Fisica d`Altes Energies, Diagonal, 647, E-08028 Barcelona (Spain)

1996-01-01

82

Weyl and ghost number anomalies in the Polyakov's light-cone gauge  

Energy Technology Data Exchange (ETDEWEB)

In this paper the conformal (Weyl) anomaly of the ghost-anti-ghost system in the 2-dimensional 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, {minus}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.

Suzuki, H. (Uji Research Center, Yukawa Inst. for Theoretical Physics, Kyoto Univ., Uji 611 (JP))

1991-05-10

83

Holonomy anomalies  

Energy Technology Data Exchange (ETDEWEB)

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. (LEW)

Bagger, J.; Nemeschansky, D.; Yankielowicz, S.

1985-05-01

84

Gauge theories of gravitation a reader with commentaries  

CERN Multimedia

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 ...

Blagojevic, Milutin

2013-01-01

85

Derivation of gauge and gravitational induced Chern-Simons terms in three dimensions  

International Nuclear Information System (INIS)

[en] We study the theory of fermions coupled to external gauge and gravitational fields. In three dimensions, the existence of massive fermions is known to lead to the induced Chern-Simons term. We derive the induced Chern-Simons term by a path integral method. (author)

1988-01-01

86

Holomorphy, Rescaling Anomalies and Exact ? Functions in Supersymmetric Gauge Theories  

International Nuclear Information System (INIS)

[en] There have been known exact'' ? functions for the gauge coupling in N=1 supersymmetric gauge theories, the so-called NSVZ ? functions. Shifman and Vainshtein (SV) further related these ? functions to the exact 1-loop running of the Wilsonian'' Gauge coupling. All these results, however, remain somewhat mysterious. We attempt to clarify these issues by presenting new perspectives on the NSVZ ? function. Our interpretation of the results is somewhat different than the one given by SV, having nothing to do with the distinction between Wilsonian'' and 1PI'' effective actions. Throughout we work in the context of the Wilsonian Renormalization Group; namely, as the cutoff of the theory is changed from M to M', we determine the appropriate changes in the bare couplings needed to keep the low energy physics fixed. The entire analysis is therefore free of infrared subtleties. When the bare Lagrangian given at the cutoff is manifestly holomorphic in the gauge coupling, we show that the required change in the holomorphic gauge coupling is exhausted at 1-loop to all orders of perturbation theory, and even non-perturbatively in some cases. On the other hand, when the bare Lagrangian has canonically normalized kinetic terms, we find that the required change in the gauge coupling is given by the NSVZ ? function. The higher order contributions in the NSVZ ? function are due to anomalous Jacobians under the rescaling of the fields done in passing from holomorphic to canonical normalization. We also give prescriptions for regularizing certain N=1 theories with an ultraviolet cutoff M preserving manifest holomorphy, starting from finite N=4 and N=2 theories. It is then in principle possible to check the validity of the exact ? function by higher order calculations in these theories. (author)

2000-01-01

87

Pioneer anomaly? Gravitational pull due to the Kuiper belt  

CERN Multimedia

In this work we study the gravitational influence of the material extending from Uranus orbit to the Kuiper belt and beyond on objects moving within these regions. We conclude that a density distribution given by $\\rho(r)=\\frac{1}{20 r}$ (for $r\\geq 20 UA$) generates a constant acceleration towards the Sun on those objects, which accounts for the blue shift detected on the Pioneers space crafts. We also discuss the effect of this gravitational pull on Neptune, and comment on the possible origin of such a matter distribution.

De Diego, J A; Zavala, I; Diego, Jos\\'e A. de; Nunez, Dario; Zavala, Jesus

2005-01-01

88

Axial anomaly in the presence of the Aharonov-Bohm gauge field  

International Nuclear Information System (INIS)

[en] 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

1994-01-01

89

Gauge dependence of the post-Newtonian radiative corrections and effective gravitational field of black holes  

International Nuclear Information System (INIS)

The problem of the interpretation of the (?/2?)0-order part of radiative corrections to the effective gravitational field is considered. It is shown that variations of the Feynman parameter in gauge conditions fixing the general covariance are equivalent to spacetime diffeomorphisms. This result is proved for arbitrary gauge conditions at the one-loop order. It implies that the gravitational radiative corrections of the order (?/2?)0 to the spacetime metric can be physically interpreted in a purely classical manner. As an example, the effective gravitational field of a black hole is calculated in the first post-Newtonian approximation, and the secular precession of a test particle orbit in this field is determined.

2002-08-15

90

Odd decays from even anomalies: Gauge mediation signatures without supersymmetry  

International Nuclear Information System (INIS)

We analyze the theory and phenomenology of anomalous global chiral symmetries in the presence of an extra dimension. We propose a simple extension of the standard model in 5D whose signatures closely resemble those of supersymmetry with gauge mediation, and we suggest a novel scalar dark matter candidate.

2009-05-15

91

Gauge Problem in the Gravitational Self-Force II. First Post Newtonian Force under Regge-Wheeler Gauge  

CERN Multimedia

We discuss the gravitational self-force on a particle in a black hole space-time. For a point particle, the full (bare) self-force diverges. It is known that the metric perturbation induced by a particle can be divided into two parts, the direct part (or the S part) and the tail part (or the R part), in the harmonic gauge, and the regularized self-force is derived from the R part which is regular and satisfies the source-free perturbed Einstein equations. In this paper, we consider a gauge transformation from the harmonic gauge to the Regge-Wheeler gauge in which the full metric perturbation can be calculated, and present a method to derive the regularized self-force for a particle in circular orbit around a Schwarzschild black hole in the Regge-Wheeler gauge. As a first application of this method, we then calculate the self-force to first post-Newtonian order. We find the correction to the total mass of the system due to the presence of the particle is correctly reproduced in the force at the Newtonian order...

Nakano, H; Sasaki, M; Nakano, Hiroyuki; Sago, Norichika; Sasaki, Misao

2003-01-01

92

Hawking Radiation, Gravitational Anomaly and Conformal Symmetry - the Origin of Universality -  

CERN Multimedia

The universal behavior of Hawking radiation is originated in the conformal symmetries of matter fields near the black hole horizon. We explain the origin of this universality based on (1) the gravitational anomaly and its higher-spin generalizations and (2) conformal transformation properties of fluxes.

Iso, Satoshi

2008-01-01

93

Gravitational solution to the Pioneer 10/11 anomaly  

CERN Multimedia

A fully relativistic modified gravitational theory including a fifth force skew symmetric field is fitted to the Pioneer 10/11 anomalous acceleration. The theory allows for a variation with distance scales of the gravitational constant G, the fifth force skew symmetric field coupling strength omega and the mass of the skew symmetric field mu=1/lambda. A fit to the available anomalous acceleration data for the Pioneer 10/11 spacecraft is obtained for a phenomenological representation of the "running" constants and values of the associated parameters are shown to exist that are consistent with fifth force experimental bounds. The fit to the acceleration data is consistent with all current satellite, laser ranging and observations for the inner planets.

Brownstein, J R

2006-01-01

94

Gauge invariant Hamiltonian formalism for spherically symmetric gravitating shells  

CERN Multimedia

The dynamics of a spherically symmetric thin shell with arbitrary rest mass and surface tension interacting with a central black hole is studied. A careful investigation of all classical solutions reveals that the value of the radius of the shell and of the radial velocity as an initial datum does not determine the motion of the shell; another configuration space must, therefore, be found. A different problem is that the shell Hamiltonians used in literature are complicated functions of momenta (non-local) and they are gauge dependent. To solve these problems, the existence is proved of a gauge invariant super-Hamiltonian that is quadratic in momenta and that generates the shell equations of motion. The true Hamiltonians are shown to follow from the super-Hamiltonian by a reduction procedure including a choice of gauge and solution of constraint; one important step in the proof is a lemma stating that the true Hamiltonians are uniquely determined (up to a canonical transformation) by the equations of motion o...

Hajicek, P

1997-01-01

95

On the chiral connection between the ferromagnet, the axisymmetric gravitational problem and the SU(2) vacuum gauge field  

International Nuclear Information System (INIS)

[en] A single chiral structure is shown to underly several three-dimensional field equations of physics, e.g. the ferromagnet, the stationary axi-symmetric gravitational problem, and the vacuum SU(2) gauge field in the Coulomb gauge. This connection invites cross-fertillization of exact solutions. As illustrations, exact finite energy solutions are obtained for the ferromagnet via the corresponding Weyl, Kerr, and Tomimatsu-Sato solutions of Einstein's gravitational equations. Comments are made on the 'local gauge invariance' of the ferromagnet and the gravitational field. (Auth.)

1978-06-12

96

Selection Rule for Generation Numbers and Gauge Anomalies for Unification Groups  

UK PubMed Central (United Kingdom)

The possibilities of global (non-perturbative) gauge anomalies for a class of gauge groups areinvestigated. Intimately connected to branching rules and topological aspect of gauge groups,the results are applied to the study of unification gauge groups such as SO(10), SU(5), E 6 ,E 8 etc. Especially, we discuss extensively about the selection rule for generation numbersN f +Nmf = even 4 in SO(10) and supersymmetric SO(10) unification theories as originallyproposed by the author1, where N f and Nmf denote the generation numbers for ordinaryfermions and mirror fermions respectively. This is due to the global gauge anomalies from somesubgroups of SO(10) in a fundamental spinor representation such that the ill-defined 'large'gauge transformations in the subgroup cannot be unwrapped in SO(10) in the quantum theoryas we noted1. A similar result related to left-right symmetric models is also given. PACS:02.20.+b, 02.40.+m, 11.15.-q.1 IntroductionSymmetries and the prope...

Huazhong Zhang

97

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.).

1986-01-01

98

Holographic conformal anomaly with bulk scalars potential from d3 and d5 gauged supergravity  

CERN Multimedia

d3 and d5 maximally SUSY gauged supergravity is considered in the parametrization (flow) of full scalar coset where kinetic term for scalars takes the standard field theory form and bulk potential is an arbitrary one subject to consistent parametrization. From such SG duals we calculate d2 and d4 holographic conformal anomaly which depends on bulk scalars potential. AdS/CFT correspondence suggests that such SG side conformal anomaly should be identified with (non-perturbative) QFT conformal anomaly (taking account of radiative corrections) for the theory living on the boundary of AdS space. In the limit of constant bulk potential and single scalar, d4 result reproduces the known exact conformal anomaly corresponding to maximally SUSY super Yang-Mills theory coupled to ${\\cal N}=4$ conformal supergravity.

Nojiri, S; Ogushi, S; Nojiri, Shin'ichi; Odintsov, Sergei D.; Ogushi, Sachiko

2000-01-01

99

Currents and the anomalies in chiral gauge theories: Dynamical approach in higher dimensions  

Energy Technology Data Exchange (ETDEWEB)

An integral representation for the fermion effective action for chiral gauge theories in d = 2n space-time dimensions is given which is able to reproduce the mismatch, as suggested by differential geometric methods, between the covariant current and the consistent current. Both types of anomalies (i.e. covariant as well as consistent) can also be calculated without having to evaluate Feynman diagrams or to introduce any local counterterms.

Banerjee, H.; Banerjee, R.

1986-07-10

100

Non-local gauge-invariant regularization and Ward identity anomalies  

CERN Multimedia

A gauge-invariant regularization of a massive spinor field interacting with external scalar, pseudoscalar, vector and axial fields is found. It is based on epsilon separating the vertices in the total Lagrangian. Rules for its use are deduced and Ward identities are written. Anomalies, present only in the divergence of the axial current, are interpreted as the high-energy contribution of the integrals associated with some loops. They can be computed in a simple way, confirming Bardeen's result. (8 refs).

Becchi, C

1973-01-01

 
 
 
 
101

The chiral anomaly and a class of two-loop finite supersymmetric gauge theories  

International Nuclear Information System (INIS)

[en] By means of the supercurrent anomaly we derive a formula for the two-loop ?-function of the matter self-interactions in an arbitrary massless N=1 supersymmetric gauge theory. As a trivial consequence we show that if such a theory is one-loop finite it is also two-loop finite, and we discuss whether this finiteness persists to all orders. (orig.)

1984-04-19

102

Chiral anomaly and a class of two-loop finite supersymmetric gauge theories  

Energy Technology Data Exchange (ETDEWEB)

By means of the supercurrent anomaly we derive a formula for the two-loop ..beta..-function of the matter self-interactions in an arbitrary massless N=1 supersymmetric gauge theory. As a trivial consequence we show that if such a theory is one-loop finite it is also two-loop finite, and we discuss whether this finiteness persists to all orders.

Jones, D.R.T.; Mezincescu, L.

1984-04-19

103

Chiral anomaly and a class of two-loop finite supersymmetric gauge theories  

Energy Technology Data Exchange (ETDEWEB)

By means of the supercurrent anomaly the authors derive a formula for the two-loop ..beta..-function of the matter self-interactions in an arbitrary massless N = 1 supersymmetric gauge theory. As a trivial consequence the authors show that if such a theory is one-loop finite it is also two-loop finite, and the authors discuss whether this finiteness persists to all orders. 22 references.

Jones, D.R.T.; Mezincescu, L.

1984-04-19

104

Validation of GOCE global gravitational field models by comparison with regional geoid and gravity anomaly surfaces  

Science.gov (United States)

The satellite gravitational gradiometry mission GOCE provides various products related to the Earth's gravitational field. One of these products is a global gravitational field model, i.e. representation of the Earth's gravitational field in terms of spherical harmonic coefficients. Such a model is used in realizing vertical reference frames in geodesy, exploring the interior of the Earth in geophysics and geology, studying the behavior of currents in oceanography, or discovering sea level rise and ice-melting in climatology. Numerous Earth's gravitational field representations have already been derived from GOCE. These representations differ according to the time span of GOCE measurements and the theoretical approach used in the harmonic analysis. To assess the quality of the GOCE models validation by independent knowledge of the gravitational field has to be performed. Global gravitational field models with limited spectral/spatial resolution are validated by terrestrial data. In this case, spectral inconsistency between the two sources of data has to be treated properly. An intuitive approach to perform the validation in a consistent way is offered by an adequate filtering. Transformation of the regional data into the spectral domain is performed firstly. Then a low-pass filter is applied to generate a smoothed version of the regional model with the same spectral content as the global GOCE model. Subsequently, the filtered signal is transformed back into the space domain where comparison with a GOCE geoid surface is performed. Despite its conceptual simplicity, the development of an optimal filtering procedure is still challenging. In this contribution we address some aspects of the filtering method. Firstly, a simulation study based on EGM2008 is performed to investigate the accuracy of the direct transformation from space to frequency domain and its inverse. Moreover, various mathematical filters are considered to filter out the short wavelengths. Secondly, the most accurate filtering procedure is applied in validation of real GOCE models. The validation experiment is performed with respect to gravity anomalies and geoid undulations over the territory of Scandinavia.

Sprlak, M.; Gerlach, C.; Pettersen, B. R.; Omang, O. C. D.

2012-04-01

105

Moduli corrections to gauge and gravitational couplings in four dimensional superstrings  

International Nuclear Information System (INIS)

We study one-loop, moduli-dependent corrections to gauge and gravitational couplings in supersymmetric vacua of the heterotic string. By exploiting their relation to the integrability condition for the associated CP-odd couplings, we derive general expressions for them, both for (2,2) and (2,0) models, in terms of tree level four-point functions in the internal N=2 superconformal theory. The (2,2) case, in particular symmetric orbifolds, is discussed in detail. (author). 11 refs

1992-01-01

106

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

1987-01-01

107

The Adler-Bardeen theorem for the axial U(1) anomaly in a general non-Abelian gauge theory  

Energy Technology Data Exchange (ETDEWEB)

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.

Lucchesi, C.; Piguet, O.; Sibold, K.

1987-04-01

108

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.)

2006-01-01

109

Anomalies and Transport Coefficients: The Chiral Gravito-Magnetic Effect  

CERN Multimedia

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.

Landsteiner, Karl; Pena-Benitez, Francisco

2011-01-01

110

Chiral symmetry breaking and nonperturbative scale anomaly in gauge field theories  

International Nuclear Information System (INIS)

The nonperturbative dynamics of chiral and scale symmetry breaking in asymtotically free and non-asymptotically free (with an ultraviolet stable fixed point) vector-like gauge theories is investigated. In the two-loop approximation analytical expressions for the chiral and gluon condensates are obtained. The hypothesis about a soft behaviour at small distances of composite operators in non-asymptotically free gauge theories with a fixed point is put forward and substantiated. It is shown that in these theories the form of the scale anomaly depends on the type of the phase in coupling constant to which it relates. A new dilaton effective lagrangian for glueball and chiral fields is suggested. The mass relation for the single scalar fermion-antifermion bound state is obtained. The important ingredient of this approach is a large (d? 2) dynamical dimension of composite chiral fields. The application of this approach to QCD and technicolour models is discussed

1987-01-01

111

Hidden symmetries, gravitational anomalies, and superalgebras of Dirac type operators on curved spaces  

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

2008-01-01

112

Anomalies of Density, Stresses, and the Gravitational Field in the Interior of Mars  

CERN Document Server

We determined the possible compensation depths for relief harmonics of different degrees and orders. The relief is shown to be completely compensated within the depth range of 0 to 1400 km. The lateral distributions of compensation masses are determined at these depths and the maps are constructed. The possible nonisostatic vertical stresses in the crust and mantle of Mars are estimated to be 64 MPa in compression and 20 MPa in tension. The relief anomalies of the Tharsis volcanic plateau and symmetric feature in the eastern hemisphere could have arisen and been maintained dynamically due to two plumes in the mantle substance that are enriched with fluids. The plumes that originate at the core of Mars can arise and be maintained by the anomalies of the inner gravitational field achieving +800 mGal in the region of plume formation, - 1200 mGal above the lower mantle-core transition layer, and -1400 mGal at the crust.

Chuikova, N A; Maksimova, T G; 10.3103/S0027134912020075

2012-01-01

113

Hypercharge Flux in IIB and F-theory: Anomalies and Gauge Coupling Unification  

CERN Multimedia

We analyse hypercharge flux GUT breaking in F-theory/Type IIB GUT models with regards to its implications for anomaly cancellation and gauge coupling unification. To this aim we exploit the Type IIB limit and consider 7-brane configurations that for the first time are guaranteed to exhibit net hypercharge flux restriction to matter curves. We show that local F-theory models with anomalies of type U(1)_Y-U(1)^2 in the massless spectrum can be consistent only if such additional U(1)s are globally geometrically massive (in the sense that they arise from non-Kahler deformations of the Calabi-Yau four-fold). We also show that the known hypercharge flux induced splitting of the gauge couplings in IIB models at tree-level can be reduced by a factor of 5 by employing a more F-theoretic twisting of U(1) flux by hypercharge flux bringing it to well within MSSM 2-loop results. In the case of net restriction of hypercharge flux to matter curves this tree-level splitting becomes more involved, is tied to the vacuum expect...

Mayrhofer, Christoph; Weigand, Timo

2013-01-01

114

Stress anomaly and gravitational potential energy of the Andean convergent margin from gravity modelling  

Science.gov (United States)

Estimates of stress anomaly and Gravitational Potential Energy (GPE) of the Nazca plate and the Andean convergent margin, as derived from gravity modelling and constrained by results of seismic experiments and other prior information, are presented. The normal stress anomalies onshore have been computed at the plate interface between the subducting slab and the overriding South American plate, and offshore on top of the oceanic Nazca plate. The GPE estimates have been made for the entire region using a 100 km vertical depth as reference level for the computation. The normal stress anomaly map of the Nazca plate, except the Nazca ridge, shows generally uniform distribution of stresses. The relatively high values of stress over the Nazca ridge are attributed to high elevation associated with young crust of the ridge. The fore-arc region is characterized by trench parallel low and high stress anomalies. The latter, which is higher by 50 to 100 MPa than in the adjacent regions, might be attributed to high density structures above the plate interface and might indicate regions of enhanced strain energy. Furthermore, the peaks of the high stress anomaly, except in the region of Iquique, correlate reasonably well with the seismicity of the trench. The high topography of the Andean mountains and the ridges in the Nazca plate exhibits high GPE values relative to the ocean. The resulting stress from GPE could influence the state of stress in the Nazca plate and adjacent regions. Provided that gravity models are well constrained, the resulting density structures could be used to infer the state of stress in the lithosphere and the associated GPE distributions.

Gutknecht, B. D.; Mahatsente, R.; Götze, H.-J.

2012-04-01

115

Frequency-domain algorithm for the Lorenz-gauge gravitational self-force  

CERN Document Server

State-of-the-art computations of the gravitational self-force (GSF) on massive particles in black hole spacetimes involve numerical evolution of the metric perturbation equations in the time-domain, which is computationally very costly. We present here a new strategy, based on a frequency-domain treatment of the perturbation equations, which offers considerable computational saving. The essential ingredients of our method are (i) a Fourier-harmonic decomposition of the Lorenz-gauge metric perturbation equations and a numerical solution of the resulting coupled set of ordinary equations with suitable boundary conditions; (ii) a generalized version of the method of extended homogeneous solutions [Phys. Rev. D {\\bf 78}, 084021 (2008)] used to circumvent the Gibbs phenomenon that would otherwise hamper the convergence of the Fourier mode-sum at the particle's location; and (iii) standard mode-sum regularization, which finally yields the physical GSF as a sum over regularized modal contributions. We present a work...

Akcay, Sarp; Barack, Leor

2013-01-01

116

Hawking radiation of black rings from anomalies  

Energy Technology Data Exchange (ETDEWEB)

We derive Hawking radiation of five-dimensional black rings from gauge and gravitational anomalies using the method proposed by Robinson and Wilczek. We find, as in the black hole case, that 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.

Chen Bin [Department of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China); He Wei [Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100080 (China)], E-mail: bchen01@pku.edu.cn, E-mail: weihe@itp.ac.cn

2008-07-07

117

Causal Version of Newtonian Theory by Time–Retardation of the Gravitational Field Explains the Flyby Anomalies  

Directory of Open Access Journals (Sweden)

Full Text Available Classical Newtonian gravitational theory does not satisfy the causality principle because it is based on instantaneous action-at-a-distance. A causal version of Newtonian theory for a large rotating sphere is derived herein by time-retarding the distance between interior circulating point-mass sources and an exterior ?eld-point. The resulting causal theory explains exactly the six ?yby anomalies reported by Anderson et al. in 2008. It also explains exactly an anomalous decrease in the Moon’s orbital speed. No other known theory has been shown to explain both the ?yby anomalies and the lunar orbit anomaly

Hafele J. C.

2013-01-01

118

Gravitational anomalies from the action for self-dual antisymmetric tensor fields in 4k+2 dimensions  

International Nuclear Information System (INIS)

[en] We show that recent actions for a single self-dual antisymmetric tensor field in 4k+2 dimensions lead to the same one-loop gravitational anomalies as obtained a few years ago by Alvarez-Gaume and Witten, who conjectured the necessary Feynman rules in the absence of an action principle

1989-08-14

119

Role of non-abelian anomalies and gauge invariance for the effective lagrangian of vector mesons  

Energy Technology Data Exchange (ETDEWEB)

We note that gauge invariance, the Wess-Zumino term and the functional Legendre transform fixes almost uniquely the effective lagrangian for the ..pi.., rho, ..omega.., A/sub 1/ system. It is shown that the only free parameters in Lsub(eff) are fsub(..pi..), msub(rho)/sup 2/, gsub(rho..pi pi..) (and eventually ..cap alpha..=(fg/msub(rho))/sup 2/). Some phenomenological implications of the flavor anomalies are discussed; in particular a recent analysis on the status of the KSFR sum rule, the msub(A1)/sup 2/=2msub(rho)/sup 2/ relation and the ..omega..->3..pi.. contact term are critically revisited.

Maiella, G.

1985-05-16

120

Wess-Zumino-type effective action for technions with light gauge bosons in a chiral-anomaly technicolor model  

Science.gov (United States)

Wess-Zumino-type effective actions for a single technion P with light gauge bosons A (gluons, photon, W+/-, and Z0) are obtained. These actions show some new anomaly processes which are not contained in the normal chiral Lagrangian. Some ?(A1-->PA2), ?(P-->A1A2), ?(A1-->A2A3P), ?(P-->3A) are estimated.

Zhang Jian-Zu

1989-01-01

 
 
 
 
121

Classical field theory. On electrodynamics, non-Abelian gauge theories and gravitation  

International Nuclear Information System (INIS)

[en] 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).

2012-01-01

122

Anomaly inflow and thermal equilibrium  

CERN Document Server

Using the anomaly inflow mechanism, we compute a contribution of gauge and (or) gravitational anomalies to the partition function of a theory in even dimensional spacetimes in backgrounds with a U(1) isometry. This contribution is a local functional of the background fields. By identifying the U(1) isometry with Euclidean time we obtain a contribution of the anomaly to the thermodynamic partition function from which hydrostatic correlators can be efficiently computed. Our result is in line with, and an extension of, previous studies on the role of anomalies in a hydrodynamic setting. Along the way we find simplified expressions for Bardeen-Zumino polynomials and various transgression formulae.

Jensen, Kristan; Yarom, Amos

2013-01-01

123

Simulation of the flyby anomaly by means of an empirical asymmetric gravitational potential with definite spatial orientation  

CERN Multimedia

All anomalous velocity increases until now observed during the Earth flybys of the spacecrafts Galileo, NEAR, Rosetta, Cassini and Messenger have been correctly calculated by computer simulation using an asymmetric potential term in addition to the Newtonian potential. The specific characteristic of this term is the lack of coupling to the rotation of the Earth or to the direction of other gravitational sources such as the Sun or Moon. Instead, the asymmetry is oriented in the direction of the Earth's motion within an assumed unique reference frame. With this assumption, the simulation results of the Earth flybys Galileo1, NEAR, Rosetta1 and Cassini hit the observed nominal values, while for the flybys Galileo2 and Messenger, which for different reasons are measured with uncertain anomaly values, the simulated anomalies are within plausible ranges. Furthermore, the shape of the simulated anomaly curve is in qualitative agreement with the measured Doppler residuals immediately following the perigee of the firs...

Busack, Hans-Juergen

2007-01-01

124

Point-splitting analysis of commutator anomalies in non-abelian chiral gauge theories  

Energy Technology Data Exchange (ETDEWEB)

A gauge covariant point-splitting regularisation is employed to calculate different anomalous commutators in four dimensional chiral gauge theories. For an external gauge field the fixed time anomalous commutator of the gauge group generators is seen to violate the Jacobi identity. The cohomological prediction can be confirmed provided the electric fields do not commute. Other commutators like the current-current and current-electric field are consistent with the Bjorken-Johnson-Low (BJL) derivation.

Ghosh, S.; Banerjee, R.

1988-10-01

125

Conformally Sequestered SUSY Breaking in Vector-like Gauge Theories  

CERN Document Server

We provide, in a framework of vector-like gauge theories, concrete models for conformal sequestering of dynamical supersymmetry (SUSY) breaking in the hidden sector. If the sequestering is sufficiently strong, anomaly mediation of the SUSY breaking may give dominant contributions to the mass spectrum of SUSY standard-model particles, leading to negative slepton masses squared. Thus, we also consider a model with gravitational gauge mediation to circumvent the tachyonic slepton problem in pure anomaly mediation models.

Ibe, M; Nakayama, Y; Shinbara, Y; Yanagida, T; Nakayama, Yu

2006-01-01

126

BRST - BFV analysis of anomalies in bosonic string theory interacting with background gravitational field  

CERN Multimedia

The general BRST-BFV analysis of anomaly in the string theory coupled to background fields is carried out. An exact equation for c-valued symbol of anomaly operator is found and structure of its solutions is studied.

Buchbinder, I L; Pershin, V D; Buchbinder, I L; Mistchuk, B R; Pershin, V D

1995-01-01

127

Anomalies.  

Science.gov (United States)

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,…

Online-Offline, 1999

1999-01-01

128

Exact solutions of the SO(3)-Yang-Mills-Higgs-system coupled to gravitation within Poincare gauge theory  

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).

1990-01-01

129

The Influence of Gravitation on the Speed of Light and an Explanation of the Pioneer 10&11 Acceleration Anomaly  

Directory of Open Access Journals (Sweden)

Full Text Available Constancy of the speed of light in time-spatial area with the same gravitational potential (or in time-spatial area with equal level of contraction/expansion of the space-time) is demonstrated. All of the experiments (“One-way”, “Two-way” and “Multiple-way” measurements) are made in time-spatial area with the same gravitational potential (or in time-spatial area with equal level of contraction/expansion of the space-time) – this is the Earth’s surface. Explanation that there is no change in the value of the speed of light in all of the above mentioned experiments is given. The speed of light (or of the electromagnetic radiation) is changing only when the light passes through time-spatial areas with different gravitational potentials (or in time-spatial areas with different levels of contraction/expansion of the space-time). The Pioneer 10 and 11 Acceleration Anomaly is actually a proving experiment of this reality.

Gocho Vasilev Sharlanov

2011-01-01

130

Anomaly cancellation and gauge group of the standard model in NCG  

CERN Document Server

It is well known that anomaly cancellation {\\it almost} determines the hypercharges in the standard model. A related (and somewhat more stronger) phenomenon takes place in Connes' NCG framework: unimodularity (a technical condition on elements of the algebra) is {\\it strictly} equivalent to anomaly cancellation (in the absence of right-handed neutrinos); and this in turn reduces the symmetry group of the theory to the standard SU(3)\\times SU(2) \\times U(1).

Alvarez, Enrique; Martín, C P; Alvarez, Enrique

1995-01-01

131

Holomorphy, rescaling anomalies and exact beta functions in supersymmetric gauge theories  

International Nuclear Information System (INIS)

[en] There have been known exact'' beta functions for the gauge coupling in N=1 supersymmetric gauge theories, the so-called NSVZ beta functions. Shifman and Vainshtein (SV) further related these beta functions to the exact 1-loop running of the Wilsonian'' gauge coupling. All these results, however, remain somewhat mysterious. We attempt to clarify these issues by presenting new perspectives on the NSVZ beta function. Our interpretation of the results is somewhat different than the one given by SV, having nothing to do with the distinction between Wilsonian'' and 1PI'' effective actions. Throughout we work in the context of the Wilsonian Renormalization Group; namely, as the cutoff of the theory is changed from M to M', we determine the appropriate changes in the bare couplings needed to keep the low energy physics fixed. The entire analysis is therefore free of infrared subtleties. When the bare Lagrangian given at the cutoff is manifestly holomorphic in the gauge coupling, we show that the required change in the holomorphic gauge coupling is exhausted at 1-loop to all orders of perturbation theory, and even non-perturbatively in some cases. On the other hand, when the bare Lagrangian has canonically normalized kinetic terms, we find that the required change in the gauge coupling is given by the NSVZ beta function. The higher order contributions in the NSVZ beta function are due to anomalous Jacobians under the rescaling of the fields done in passing from holomorphic to canonical normalization. We also give prescriptions for regularizing certain N=1 theories with an ultraviolet cutoff M preserving manifest holomorphy, starting from finite N=4 and N=2 theories. It is then in principle possible to check the validity of the exact beta function by higher order calculations in these theories. (author)

2000-01-01

132

D-brane Charges in Gravitational Duals of 2+1 Dimensional Gauge Theories and Duality Cascades  

CERN Document Server

We perform a systematic analysis of the D-brane charges associated with string theory realizations of d=3 gauge theories, focusing on the examples of the N=4 supersymmetric U(N)xU(N+M) Yang-Mills theory and the N=3 supersymmetric U(N)xU(N+M) Yang-Mills-Chern-Simons theory. We use both the brane construction of these theories and their dual string theory backgrounds in the supergravity approximation. In the N=4 case we generalize the previously known gravitational duals to arbitrary values of the gauge couplings, and present a precise mapping between the gravity and field theory parameters. In the N=3 case, which (for some values of N and M) flows to an N=6 supersymmetric Chern-Simons-matter theory in the IR, we argue that the careful analysis of the charges leads to a shift in the value of the B-field in the IR solution by 1/2, in units where its periodicity is one, compared to previous claims. We also suggest that the N=3 theories may exhibit, for some values of N and M, duality cascades similar to those of ...

Aharony, Ofer; Hirano, Shinji; Ouyang, Peter

2009-01-01

133

Theoretical physics 3. Classical field theory. On electrodynamics, non-Abelian gauge theories, and gravitation. 3. ed.  

International Nuclear Information System (INIS)

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.

2010-01-01

134

Gauge structure, anomalies and mass generation in a three dimensional thirring model  

International Nuclear Information System (INIS)

We consider a three dimensional model of spinor fields with a Thirring like, quadrilinear self interaction. Using either two or four component Dirac spinors, we prove that the 1/N expansion for the model is renormalizable if a gauge structure to select physical quantities is introduced. For certain values of the coupling the leading 1/N approximation exihibits bound state poles. Dynamical breaking of parity or chiral symmetry is shown to occur as a cooperative effect of different orders of 1/N, if N is smaller than the critical value Nc = 128/x2D', where D is two or four depending on wether the fermion field has two or four components. (author).

1990-01-01

135

Canonical formulation of gravitational teleparallelism in $2+1$ dimensions in Schwinger's time gauge  

CERN Multimedia

We consider the most general class of teleparallel gravitational theoriesquadratic in the torsion tensor, in three space-time dimensions, and carry outa detailed investigation of its Hamiltonian formulation in Schwinger's timegauge. This general class is given by a family of three-parameter theories. Aconsistent implementation of the Legendre transform reduces the original theoryto a one-parameter family of theories. By calculating Poisson brackets we showexplicitely that the constraints of the theory constitute a first class set.Therefore the theory is well defined regarding time evolution. The freeparameter may be fixed by requiring the theory to display the Newtonian limit.The resulting theory does not coincide with Einstein's general relativity in2+1 dimensions.

Sousa, A A

2000-01-01

136

Renormalizable Quantum Gauge General Relativity  

CERN Multimedia

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 ...

Wu, N

2003-01-01

137

Arbitrary parameters in implicit regularization and democracy within perturbative description of 2-dimensional gravitational anomalies  

International Nuclear Information System (INIS)

[en] 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

2006-01-26

138

An anomaly-free model in six dimensions  

International Nuclear Information System (INIS)

We show that a gauged supergravity theory based on E6xE7xU(1) is free of gauge and gravitational anomalies in six dimensions. It compactifies to (Minkowski)4xS2 by the standard monopole mechanism. With a monopole of strength n in E6, the resulting four-dimensional theory exhibits chiral SO(10)xU(1) with 2|n| families (and no antifamilies). Supersymmetry is broken. (author).

1984-01-01

139

Moduli corrections to gravitational couplings from string loops  

International Nuclear Information System (INIS)

We study moduli dependent threshold corrections to gravitational couplings in the case of the heterotic string compactified on a symmetric orbifold, for untwisted moduli, extending previous analysis on gauge couplings. Like in the gauge case, the contribution comes entirely from the spacetime N=2 sector. As a byproduct, this calculation provides a simple derivation of the trace anomaly coefficients for the different fields coupled to gravity. (author). 8 refs

1992-01-01

140

Anomalies and supersymmetry  

International Nuclear Information System (INIS)

[en] The problem of quantum anomalies in supersymmetric gauge theories is reviewed. They are the anomaly of supersymmetry, the axial anomaly and the anomaly of supercurrent. The consequenes of quantum anomaly are analysed for the axial anomaly in QED. It is emphasized that supersymmetry itself is not anomalous. The supercurrent anomalies do not contradict that of the axial current and form a supermultiplet of anomalies. Anomalies do not destroy the supersymmetry

1985-01-01

 
 
 
 
141

Anomalies and Hawking radiation from the Reissner-Nordstroem black hole with a global monopole  

Energy Technology Data Exchange (ETDEWEB)

We extend the work by Iso, Umetsu and Wilczek (2006 Phys. Rev. Lett. 96 151302) to derive the Hawking flux via gauge and gravitational anomalies of a most general two-dimensional non-extremal black hole spacetime with the determinant of its diagonal metric differing from unity {radical} (-g)1) {ne} 1 and use it to investigate Hawking radiation from the Reissner-Nordstroem black hole with a global monopole by requiring the cancellation of anomalies at the horizon. It is shown that the compensating energy-momentum and gauge fluxes required to cancel gravitational and gauge anomalies at the horizon are precisely equivalent to the (1 + 1)-dimensional thermal fluxes associated with Hawking radiation emanating from the horizon at the Hawking temperature. These fluxes are universally determined by the value of anomalies at the horizon.

Wu Shuangqing; Peng Junjin [College of Physical Science and Technology, Central China Normal University, Wuhan, Hubei 430079 (China)

2007-10-21

142

Measuring the Size of Quasar Broad-Line Clouds Through Time Delay Light-Curve Anomalies of Gravitational Lenses  

CERN Document Server

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 ...

Wyithe, S; Wyithe, Stuart; Loeb, Abraham

2002-01-01

143

Interpretation of a Short-Term Anomaly in the Gravitational Microlensing Event MOA-2012-BLG-486  

CERN Document Server

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 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 pla...

Hwang, K -H; Bond, I A; Sumi, T; Han, C; Gaudi, B S; Gould, A; Bozza, V; Beaulieu, J -P; Tsapras, Y; Abe, F; Bennett, D P; Botzler, C S; Chote, P; Freeman, M; Fukui, A; Fukunaga, D; Harris, P; Itow, Y; Koshimoto, N; Ling, C H; Masuda, K; Matsubara, Y; Muraki, Y; Namba, S; Ohnishi, K; Rattenbury, N J; Saito, To; Sullivan, D J; Sweatman, W L; Suzuki, D; Tristram, P J; Wada, K; Yamai, N; Yock, P C M; Yonehara, A; de Almeida, L Andrade; DePoy, D L; Dong, Subo; Jablonski, F; Jung, Y K; Kavka, A; Lee, C -U; Park, H; Pogge, R W; Shin, I -G; Yee, J C; Albrow, M D; Bachelet, E; Batista, V; Brillant, S; Caldwell, J A R; Cassan, A; Cole, A; Corrales, E; Coutures, Ch; Dieters, S; Prester, D Dominis; Donatowicz, J; Fouqué, P; Greenhill, J; Jørgensen, U G; Kane, S R; Kubas, D; Marquette, J -B; Martin, R; Meintjes, P; Menzies, J; Pollard, K R; Williams, A; Wouters, D; Bramich, D M; Dominik, M; Horne, K; Browne, P; Hundertmark, M; Ipatov, S; Kains, N; Snodgrass, C; Steele, I A; Street, R A

2013-01-01

144

Path integral quantization of gravitational interactions  

International Nuclear Information System (INIS)

[en] 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)

1985-01-01

145

Gravitational interaction of fermion antisymmetric tensor fields  

International Nuclear Information System (INIS)

[en] 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)

1985-01-01

146

Quantization of 2D abelian gauge theory without the kinetic term of gauge field as anomalous gauge theory  

CERN Document Server

The massless Schwinger model without the kinetic term of gauge field has gauge anomaly. We quantize the model as an anomalous gauge theory in the most general class of gauge conditions. We show that the gauge field becomes a dynamical variable because of gauge anomaly.

Koseki, M

1995-01-01

147

The global anomaly of the self-dual field in general backgrounds  

CERN Document Server

We prove a formula for the global gravitational anomaly of the self-dual field theory in the presence of background gauge fields, assuming the results of arXiv:1110.4639. Along the way, we also clarify various points about the self-dual field theory. In particular, we give a general definition of the theta characteristic entering its partition function and settle the issue of its possible metric dependence. We treat the cohomological version of type IIB supergravity as an example of the formalism. We show the apparent existence of a mixed gauge-gravitational global anomaly, occurring when the B-field and Ramond-Ramond 2-form gauge fields have non-trivial Wilson lines, and suggest a way in which it could cancel.

Monnier, Samuel

2013-01-01

148

Anomaly-free supersymmetric models in six dimensions  

CERN Document Server

The conditions for the cancellation of all gauge, gravitational, and mixed anomalies of N=1 supersymmetric models in six dimensions are reviewed and illustrated by a number of examples. Of particular interest are models that cannot be realized perturbatively in string theory. An example of this type, which we verify satisfies the anomaly cancellation conditions, is the K3 compactification of the SO(32) theory with small instantons recently proposed by Witten. When the instantons coincide it has gauge group SO(32) \\times Sp(24). Two new classes of models, for which non-perturbative string constructions are not yet known, are also presented. They have gauge groups SO(2n+8)\\times Sp(n) and SU(n)\\times SU(n), where n is an arbitrary positive integer.

Schwarz, J H

1995-01-01

149

Anomaly analysis of Hawking radiation from Kaluza-Klein black hole with squashed horizon  

Energy Technology Data Exchange (ETDEWEB)

Considering gravitational and gauge anomalies at the horizon, a new method to derive Hawking radiation from black holes has been developed by Wilczek et al. In this paper, we apply this method to non-rotating and rotating Kaluza-Klein black holes with squashed horizon, respectively. For the rotating case, we found that, after dimensional reduction, an effective U(1) gauge field is generated by an angular isometry. The results show that the gauge current and energy-momentum tensor fluxes are exactly equivalent to Hawking radiation from the event horizon. (orig.)

Wei, Shao-Wen; Li, Ran; Liu, Yu-Xiao; Ren, Ji-Rong [Lanzhou University, Institute of Theoretical Physics, Lanzhou (China)

2010-01-15

150

Anomaly analysis of Hawking radiation from Kaluza-Klein black hole with squashed horizon  

International Nuclear Information System (INIS)

Considering gravitational and gauge anomalies at the horizon, a new method to derive Hawking radiation from black holes has been developed by Wilczek et al. In this paper, we apply this method to non-rotating and rotating Kaluza-Klein black holes with squashed horizon, respectively. For the rotating case, we found that, after dimensional reduction, an effective U(1) gauge field is generated by an angular isometry. The results show that the gauge current and energy-momentum tensor fluxes are exactly equivalent to Hawking radiation from the event horizon. (orig.)

2010-01-01

151

Theoretical physics 3. Classical field theory. On electrodynamics, non-Abelian gauge theories, and gravitation. 3. ed.; Theoretische Physik 3. Klassische Feldtheorie. Von Elektrodynamik, nicht-Abelschen Eichtheorien und Gravitation  

Energy Technology Data Exchange (ETDEWEB)

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.)

Scheck, Florian [Mainz Univ. (Germany). Fachbereich Physik

2010-07-01

152

Three loop gauge beta-function for the most general single gauge-coupling theory  

CERN Document Server

We calculate the three loop contribution to the beta-function of the gauge coupling constant in a general, anomaly-free, renormalisable gauge field theory involving a single gauge coupling using the background field method in the MSbar scheme.

Pickering, A G M; Jones, D R T

2001-01-01

153

Gravitational energy-momentum density in teleparallel gravity  

UK PubMed Central (United Kingdom)

In the context of a gauge theory for the translation group, a conserved energy-momentum gauge current for the gravitational field is obtained. It is a true spacetime and gauge tensor, and transforms covariantly under global Lorentz transformations. By rewriting the gauge gravitational field equation in a purely spacetime form, it becomes the teleparallel equivalent of Einstein's equation, and the gauge current reduces to the Moller's canonical energy-momentum density of the gravitational field.

de Andrade VC; Guillen LC; Pereira JG

2000-05-01

154

Anomalies and gravity  

Science.gov (United States)

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 ? F = dC arise in the chiral anomaly, even when coupled to gravity. Implications for Ashtekar's canonical approach to quantum gravity are discussed.

Mielke, Eckehard W.

2006-09-01

155

Anomalies and gravity  

International Nuclear Information System (INIS)

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.

2006-09-25

156

Higgs vacuum in gravitation theory  

International Nuclear Information System (INIS)

Based on the description of the gravitational field as the Higgs-Goldstone one in the gravitational gauge theory, an existence of the Higgs gravitational vacuum is predicted, and the model of the Higgs vacuum is constructed. The Higgs material fiel vacuum may serve as the material sourse of the latter. At a classical level it means an existence of the background gravitational field induced by the background Higgs matter.

1986-01-01

157

Holographic renormalization of cascading gauge theories  

Science.gov (United States)

We perform a holographic renormalization of cascading gauge theories. Specifically, we find the counterterms that need to be added to the gravitational action of the backgrounds dual to the cascading theory of Klebanov and Tseytlin, compactified on an arbitrary four-manifold, in order to obtain finite correlation functions (with a limited set of sources). We show that it is possible to truncate the action for deformations of this background to a five-dimensional system coupling together the metric and four scalar fields. Somewhat surprisingly, despite the fact that these theories involve an infinite number of high-energy degrees of freedom, we find finite answers for all one-point functions (including the conformal anomaly). We compute explicitly the renormalized stress tensor for the cascading gauge theories at high temperature and show how our finite answers are consistent with the infinite number of degrees of freedom. Finally, we discuss ambiguities appearing in the holographic renormalization we propose for the cascading gauge theories; our finite results for the one-point functions have some ambiguities in curved space (including the conformal anomaly) but not in flat space.

Aharony, Ofer; Buchel, Alex; Yarom, Amos

2005-09-01

158

Conformal Anomalies Recent Progress  

CERN Document Server

We present a brief review of some recent results on conformal anomalies in four and more dimensions. The discussion is intended for relativists, so some background on the quantum origin of anomalies and of their simple properties in D=2 is also provided. Topics treated include a critical review of the effective gravitational action uniqueness problem and the derivation of beta functions, independent of ultraviolet behavior, from the type B anomaly.

Deser, Stanley D

1996-01-01

159

Abelian gauge theories with tensor gauge fields  

International Nuclear Information System (INIS)

[en] Gauge fields of arbitrary tensor type are introduced. In curved space-time the gravitational field serves as a bridge joining different gauge fields. The theory of second order tensor gauge field is developed on the basis of close analogy to Maxwell electrodynamics. The notion of tensor current is introduced and an experimental test of its detection is proposed. The main result consists in a coupled set of field equations representing a generalization of Maxwell theory in which the Einstein equivalence principle is not satisfied. (author)

1984-01-01

160

Monopoles, gauge fields, and anomalies  

International Nuclear Information System (INIS)

The possible catalysis of baryon disintegration by magnetic poles is a beautiful example of the way in which monopoled illuminate fundamental concepts of physics. This hypothetical process is followed step by step, with an effort to minimize arbitrary hypotheses and to state clearly those which remain, as well as the consequences of changing them. The conclusions are that there should be a large cross section for catalysis in collisions of slow monopoles with nucleons, though not with large nuclei, but the intrinsic rate for destruction of a nucleon captured by a pole could be many orders of magnitude below the 10/sup 23/ per second which characterizes strong interactions. It is argued that Rubakov's and Callan's pictures of catalysis are compatible but distinct, and either permits a strong rate, but requires at least a weak rate.

1983-01-01

 
 
 
 
161

Gravitational anyonization  

International Nuclear Information System (INIS)

The statistics of scalar matter changes when it is coupled to a U(1) gauge field with Chern-Simons dynamics, because all particles carry a magnetic flux and therefore give rise to Aharonov-Bohm phases when they move around each other. We argue that also the ''dual'' version of the Aharonov-Bohm effect, the Aharonov-Casher effect, can give rise to Berry phases which transmute ordinary particles into anyons. The Aharonov-Casher effect consists of an extra topological phase in the wave function of a magnetic moment moving around an electric charge. Considering (2+1)-dimensional Dirac fermions at low energies, both effects are present, and the fermions are turned into (interacting) anyons even though there is no Chern-Simons term included in the action. We study in detail the gravitational analogue of this mechanism. The post-Newtonian approximation is applied to the gravitational interaction of (2+1)-dimensional particles with spin, and to stringlike matter distributions with internal angular momentum in 3+1 dimensions. The action for gravity is taken to be the pure Einstein-Hilbert term. In the adiabatic limit one finds scrA?v-type interactions where scrA is a long-range vortex field. These interactions give rise to various kinds of Berry phases, in particular to the gravitational analogues of the Aharonov-Bohm and the Aharonov-Casher phases. The former occurs when a mass moves around a particle with spin, and the latter arises when a particle with spin moves in the Newtonian scalar potential of a second (spinless) particle. These Berry phases lead to a ''self-anyonization'' of particles with nonzero spin. The topological term in their effective action has the same structure as the one which obtains when spinless particles are considered, but with a gravitational Chern-Simons term included in the action for the gravitational field.

1991-01-01

162

Gauge transformation in relativistic theory of gravity  

International Nuclear Information System (INIS)

The paper contains a formulation of the gauge principle and a construction on its base of the Lagrangian density of the gravitational field. It is shown that Riemann space-time geometry is defined unabigously only in the presence of matter. In virtue of the gauge arbitrariness, Riemann space-time geometry could not in principle be fixed by gravitational fields only.

1985-01-01

163

$Z'$ Phenomenology: A Novel Analysis and Fit in Combination of Chiral Effective Theory and Anomaly Cancellation  

CERN Multimedia

To investigate $Z'$ phenomenology model-independent, we combine chiral effective theory with anomaly cancellation conditions without any other model input. We focus on $Z'$ mixings with $\\gamma-Z$ in both mass and kinetic parts and calculate contributions to oblique $S,T,U$. The three sets of anomaly-free fermion $U(1)'$ charges parameterize the $Z'$ interactions with fermions. The cancellation of the $[U(1)']^3$ anomaly and mixing gravitational-gauge anomaly determines the number of right-handed neutrinos. We also find a novel relation between the charge assignments and Stueckelberg coupling in terms of the renormalized electromagnetic current. A global fit to the electroweak precise observables shows that typical values for the mixing parameters are of order $10^{-3}$. In spite of this strict limit, we obtain a negative $S$ parameter contribution.

Zhang, Ying

2011-01-01

164

Aetiology of sigma model anomalies  

Energy Technology Data Exchange (ETDEWEB)

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 them to several supersymmetric sigma models. Some of these are found to be anomalous.

Moore, G.; Nelson, P.

1985-07-01

165

Relativistic rigid particles: classical tachyons and quantum anomalies  

International Nuclear Information System (INIS)

[en] 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.)

1993-01-01

166

Chern-Simons Forms in Gravitation Theories  

CERN Document Server

The Chern-Simons (CS) form evolved from an obstruction in mathematics into an important object in theoretical physics. In fact, the presence of CS terms in physics is more common than one may think: they seem to play an important role in high Tc superconductivity and in recently discovered topological insulators. In classical physics, the minimal coupling in electromagnetism and to the action for a mechanical system in Hamiltonian form are examples of CS functionals. CS forms are also the natural generalization of the minimal coupling between the electromagnetic field and a point charge when the source is not point-like but an extended fundamental object, a membrane. They are found in relation with anomalies in quantum field theories, and as Lagrangians for gauge fields, including gravity and supergravity. A cursory review of the role of CS forms in gravitation theories is presented at an introductory level.

Zanelli, Jorge

2012-01-01

167

Conservative corrections to the innermost stable circular orbit (ISCO) of a Kerr black hole: A new gauge-invariant post-Newtonian ISCO condition, and the ISCO shift due to test-particle spin and the gravitational self-force  

International Nuclear Information System (INIS)

The innermost stable circular orbit (ISCO) delimits the transition from circular orbits to those that plunge into a black hole. In the test-mass limit, well-defined ISCO conditions exist for the Kerr and Schwarzschild spacetimes. In the finite-mass case, there are a large variety of ways to define an ISCO in a post-Newtonian (PN) context. Here I generalize the gauge-invariant ISCO condition of Blanchet and Iyer [Classical Quantum Gravity 20, 755 (2003)] to the case of spinning (nonprecessing) binaries. The Blanchet-Iyer ISCO condition has two desirable and unexpected properties: (1) it exactly reproduces the Schwarzschild ISCO in the test-mass limit, and (2) it accurately approximates the recently calculated shift in the Schwarzschild ISCO frequency due to the conservative-piece of the gravitational self-force [L. Barack and N. Sago, Phys. Rev. Lett. 102, 191101 (2009)]. The generalization of this ISCO condition to spinning binaries has the property that it also exactly reproduces the Kerr ISCO in the test-mass limit (up to the order at which PN spin corrections are currently known). The shift in the ISCO due to the spin of the test-particle is also calculated. Remarkably, the gauge-invariant PN ISCO condition exactly reproduces the ISCO shift predicted by the Papapetrou equations for a fully relativistic spinning particle. It is surprising that an analysis of the stability of the standard PN equations of motion is able (without any form of 'resummation') to accurately describe strong-field effects of the Kerr spacetime. The ISCO frequency shift due to the conservative self-force in Kerr is also calculated from this new ISCO condition, as well as from the effective-one-body Hamiltonian of Barausse and Buonanno [Phys. Rev. D 81, 084024 (2010)]. These results serve as a useful point of comparison for future gravitational self-force calculations in the Kerr spacetime.

2011-01-15

168

GUT scale and superpartner masses from anomaly mediated supersymmetry breaking  

Energy Technology Data Exchange (ETDEWEB)

We consider models of anomaly-mediated supersymmetry breaking (AMSB) in which the grand unification (GUT) scale is determined by the vacuum expectation value of a chiral superfield. If the anomaly-mediated contributions to the potential are balanced by gravitational-strength interactions, a GUT scale of M{sub Planck}/(16{pi}{sup 2}) can be generated. The GUT threshold also affects superpartner masses, and can easily give rise to realistic predictions if the GUT gauge group is asymptotically free. We give an explicit example of a model with these features, in which the doublet-triplet splitting problem is solved. The resulting superpartner spectrum is very different from that of previously considered AMSB models, with gaugino masses typically unifying at the GUT scale.

Chacko, Z.; Luty, Markus A.; Ponton, Eduardo; Shadmi, Yael; Shirman, Yuri

2001-09-01

169

A Gravity Dual of the Chiral Anomaly  

CERN Document Server

We study effects associated with the chiral anomaly for a cascading $SU(N+M)\\times SU(N)$ gauge theory using gauge/gravity duality. In the gravity dual the anomaly is a classical feature of the supergravity solution, and the breaking of $U(1)$ R-symmetry down to ${\\bf Z}_{2M}$ proceeds via the Higgs mechanism.

Klebanov, Igor R; Witten, Edward; Klebanov, Igor R.; Ouyang, Peter; Witten, Edward

2002-01-01

170

Semidirect product gauge group $\\left[SU(3)_{\\rm c} \\times SU(2)_{\\rm L}\\right]\\rtimes U(1)_{\\rm Y}$ and quantization of hypercharge  

CERN Multimedia

In the Standard Model the hypercharges of quarks and leptons are not determined by the gauge group $SU(3)_{\\rm c} \\times SU(2)_{\\rm L} \\times U(1)_{\\rm Y}$ alone. We show that, if we choose the semidirect product group $[SU(3)_{\\rm c} \\times SU(2)_{\\rm L}] \\rtimes U(1)_{\\rm Y}$ as its gauge group, the hyperchages are settled to be $n/6 \\mod {\\mathbb{Z}}\\;(n = 0,1,3,4) $. In addition, the conditions for gauge-anomaly cancellation give strong constraints. As a result, the ratios of the hypercharges are uniquely determined and the gravitational anomaly is automatically canceled. The standard charge assignment to quarks and leptons can be properly reproduced. For exotic matter fields their hypercharges are also predicted.

Hattori, Chuichiro; Matsuoka, Takeo

2010-01-01

171

Anomalies in nonlinear sigma models  

International Nuclear Information System (INIS)

[en] Certain nonlinear sigma models with fermions suffer from an anomaly similar to the one in non-Abelian gauge theory. The authors exhibit this anomaly using both perturbative and global methods. The affected theories are ill defined and hence unsuitable for describing low-energy dynamics. They include certain supersymmetric models in four-space dimensions

1989-01-01

172

Topology and non-Abelian anomalies  

International Nuclear Information System (INIS)

[en] The use of topological methods in elucidating the structure of non-Abelian anomalies is presented. It is shown that one can understand the existence of anomalies in theories of Weyl fermions coupled to gauge fields, in terms of the topological properties of the space of gauge fields modulo gauge transformations. The author outlines how this topological structure appears both in the Euclidean and Hamiltonian formulation of the quantum mechanics of fermions

1984-11-03

173

Path Integral Quantization of Quantum Gauge General Relativity  

CERN Document Server

Path integral quantization of quantum gauge general relativity is discussed in this paper. First, we deduce the generating functional of green function with external fields. Based on this generating functional, the propagators of gravitational gauge field and related ghost field are deduced. Then, we calculate Feynman rules of various interaction vertices of three or four gravitational gauge fields and vertex between ghost field and gravitational gauge field. Results in this paper are the bases of calculating vacuum polarization of gravitational gauge field and vertex correction of gravitational couplings in one loop diagram level. As we have pointed out in previous paper, quantum gauge general relativity is perturbative renormalizable, and a formal proof on its renormalizability is also given in the previous paper. Next step, we will calculate one-loop and two-loop renormalization constant, and to prove that the theory is renormalizable in one-loop and two-loop level by direct calculations.

Wu, Ning

2008-01-01

174

Anomalies and de Sitter radiation from the generic black holes in de Sitter spaces  

International Nuclear Information System (INIS)

Robinson-Wilczek's recent work shows that, the energy-momentum tensor flux required to cancel gravitational anomaly at the event horizon of a Schwarzschild-type black hole has an equivalent form to that of a (1+1)-dimensional blackbody radiation at the Hawking temperature. Motivated by their work, Hawking radiation from the cosmological horizons of the general Schwarzschild-de Sitter and Kerr-de Sitter black holes, has been studied by the method of anomaly cancellation. The result shows that the absorbing gauge current and energy momentum tensor fluxes required to cancel gauge and gravitational anomalies at the cosmological horizon are precisely equal to those of Hawking radiation from it. It should be emphasized that the effective field theory for generic black holes in de Sitter spaces should be formulated within the region between the event horizon (EH) and the cosmological horizon (CH), to integrate out the classically irrelevant ingoing modes at the EH and the classically irrelevant outgoing modes at the CH, respectively.

2007-07-19

175

Holographic 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.

2009-01-01

176

Holographic 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.

2009-06-19

177

Inflato-Natural Leptogenesis: Leptogenesis in Chromo-Natural Inflation and Gauge-Flation  

CERN Multimedia

In Ref. [1] a scenario of leptogenesis, the gravi-leptogensis, was introduced. In this scenario the lepton asymmetry is created by the gravitational chiral anomaly within the standard model of particle physics, during inflation, for models of inflation driven by pseudoscalar field(s). In the gravi-leptogensis scenario of Ref. [1], however, the pseudoscalar driven model of inflation was not specified. In this work we show that the inflation model can be successfully chosen to be the chromo-natural inflation or the gauge-flation.

Noorbala, Mahdiyar

2012-01-01

178

Conservative corrections to the innermost stable circular orbit (ISCO) of a Kerr black hole: A new gauge-invariant post-Newtonian ISCO condition, and the ISCO shift due to test-particle spin and the gravitational self-force  

Science.gov (United States)

The innermost stable circular orbit (ISCO) delimits the transition from circular orbits to those that plunge into a black hole. In the test-mass limit, well-defined ISCO conditions exist for the Kerr and Schwarzschild spacetimes. In the finite-mass case, there are a large variety of ways to define an ISCO in a post-Newtonian (PN) context. Here I generalize the gauge-invariant ISCO condition of Blanchet and Iyer [Classical Quantum GravityCQGRDG0264-9381 20, 755 (2003)10.1088/0264-9381/20/4/309] to the case of spinning (nonprecessing) binaries. The Blanchet-Iyer ISCO condition has two desirable and unexpected properties: (1) it exactly reproduces the Schwarzschild ISCO in the test-mass limit, and (2) it accurately approximates the recently calculated shift in the Schwarzschild ISCO frequency due to the conservative-piece of the gravitational self-force [L. Barack and N. Sago, Phys. Rev. Lett. 102, 191101 (2009)PRLTAO0031-900710.1103/PhysRevLett.102.191101]. The generalization of this ISCO condition to spinning binaries has the property that it also exactly reproduces the Kerr ISCO in the test-mass limit (up to the order at which PN spin corrections are currently known). The shift in the ISCO due to the spin of the test-particle is also calculated. Remarkably, the gauge-invariant PN ISCO condition exactly reproduces the ISCO shift predicted by the Papapetrou equations for a fully relativistic spinning particle. It is surprising that an analysis of the stability of the standard PN equations of motion is able (without any form of “resummation”) to accurately describe strong-field effects of the Kerr spacetime. The ISCO frequency shift due to the conservative self-force in Kerr is also calculated from this new ISCO condition, as well as from the effective-one-body Hamiltonian of Barausse and Buonanno [Phys. Rev. DPRVDAQ1550-7998 81, 084024 (2010)10.1103/PhysRevD.81.084024]. These results serve as a useful point of comparison for future gravitational self-force calculations in the Kerr spacetime.

Favata, Marc

2011-01-01

179

Mixed States from Anomalies  

CERN Multimedia

There are several instances where quantum anomalies of continuous and discrete classical symmetries play an important role in fundamental physics. Examples come from chiral anomalies in the Standard Model of fundamental interactions and gravitational anomalies in string theories. Their generic origin is the fact that classical symmetries may not preserve the domains of quantum operators like the Hamiltonian. In this work, we show by simple examples that anomalous symmetries can often be implemented at the expense of working with mixed states having non-zero entropies. In particular there is the result on color breaking by non-abelian magnetic monopoles. This anomaly can be rectified by using impure states. We also argue that non-abelian groups of twisted bundles are always anomalous for pure states sharpening an earlier argument of Sorkin and Balachandran. This is the case of mapping class groups of geons indicating that "large" diffeos are anomalous for pure states in the presence of geons. Nevertheless diff...

Balachandran, A P

2011-01-01

180

Torsional anomalies, Hall viscosity, and bulk-boundary correspondence in topological states  

Science.gov (United States)

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 particular, we find new torsional contributions to the covariant diffeomorphism anomaly in 1+1 dimensions. Including parity-even contributions, we find that the renormalized generating functionals of the two topological phases differ by a chiral gravity action with a negative cosmological constant. This (nondynamical) chiral gravity action and the corresponding physics of the interface theory is reminiscent of well-known properties of dynamical holographic gravitational systems. Finally, we consider some properties of spectral flow of the edge theory driven by torsional dislocations.

Hughes, Taylor L.; Leigh, Robert G.; Parrikar, Onkar

2013-07-01

 
 
 
 
181

Conservative corrections to the innermost stable circular orbit (ISCO) of a Kerr black hole: a new gauge-invariant post-Newtonian ISCO condition, and the ISCO shift due to test-particle spin and the gravitational self-force  

CERN Document Server

The innermost stable circular orbit (ISCO) delimits the transition from circular orbits to those that plunge into a black hole. In the test-mass limit, well-defined ISCO conditions exist for the Kerr and Schwarzschild spacetimes. In the finite-mass case, there are a large variety of ways to define an ISCO in a post-Newtonian (PN) context. Here I generalize the gauge-invariant ISCO condition of Blanchet & Iyer (2003) to the case of spinning (non-precessing) binaries. The Blanchet-Iyer ISCO condition has two desirable and unexpected properties: (1) it exactly reproduces the Schwarzschild ISCO in the test-mass limit, and (2) it accurately approximates the recently-calculated shift in the Schwarzschild ISCO frequency due to the conservative-piece of the gravitational self-force [Barack & Sago (2009)]. The generalization of this ISCO condition to spinning binaries has the property that it also exactly reproduces the Kerr ISCO in the test-mass limit (up to the order at which PN spin corrections are currentl...

Favata, Marc

2010-01-01

182

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.)

1985-01-01

183

The aetiology of sigma model anomalies  

Science.gov (United States)

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 them to several supersymmetric sigma models. Some of these are found to be anomalous.

Moore, Gregory; Nelson, Philip

1985-03-01

184

Relevance of induced gauge interactions in decoherence  

International Nuclear Information System (INIS)

Decoherence in quantum cosmology is shown to occur naturally in the presence of induced geometric gauge interactions associated with particle production. A new ''gauge'' - variant form of the semiclassical Einstein equations is also presented which makes the non-gravitating character of the vacuum polarization energy explicit. (author). 20 refs

1994-01-01

185

A Generalized Gauge Theory of Gravity  

CERN Document Server

In this paper, we discuss a gravitational theory based on the generalized gauge field. Our Lagrangian is invariant not only under local Lorentz transformation and the ordinary gauge transformation but also under a new gauge transformation. We show that the gauge field associated with this new transformation is a second-rank tensor field and that the Einstein-Hilbert term can be derived from our Lagrangian when the gauge field has a vacuum expectation value. We also show that our model provides a Lagrangian for the scalar-tensor theory.

Nishida, Kouzou

2012-01-01

186

Gauge and radiation conditions in numerical relativity  

International Nuclear Information System (INIS)

[en] Gauge conditions suitable for numerical calculations of emission of gravitational radiation by compact sources are explored, with particular emphasis on algebraic conditions which simplify the structure of the Einstein equations. The expansion of the radiation field in powers of r-1 is compared in different gauges, and formulas for outgoing wave boundary conditions and asymptotic energy flux in the waves are obtained in the radial gauge which are accurate through order r-2. (Auth.)

1983-01-01

187

How Noncommutative Gauge Theories Couple to Gravity  

CERN Document Server

We study coupling of a noncommutative gauge theory on a brane to closed string in the bulk. We derive an expression for the gauge theory operator dual to the bulk graviton and find that it is different from what was expected in the literature when the graviton is polarized in the noncommutative directions. We also clarify some aspects of the correspondence between operators in the gauge theory and boundary conditions in the dual gravitational description.

Okawa, Y; Okawa, Yuji; Ooguri, Hirosi

2001-01-01

188

Strings, Gauge Fields and Membranes  

CERN Multimedia

We present an overview of the intimate relationship between string and D-brane dynamics, and the dynamics of gauge and gravitational fields in three spacetime dimensions. The successes, prospects and open problems in describing both perturbative and nonperturbative aspects of string theory in terms of three-dimensional quantum field theory are highlighted.

Szabó, R J

2004-01-01

189

Wilson loops in Kerr gravitation  

Energy Technology Data Exchange (ETDEWEB)

The ordered integrals for several paths in Kerr gravitation is computed in a compact form. When the path is closed we discuss its relation with the angular parallel displacement and calculate the corresponding Wilson loop. The validity of Mandelstam relations for gauge fields is also explicitly verified.

Bollini, C.G.; Giambiagi, J.J.; Tiomno, J. (Centro Brasileiro de Pesquisas Fisicas, Rio de Janeiro)

1981-05-02

190

Superconnections, Anomalies and Non-BPS Brane Charges  

CERN Multimedia

The properties of brane-antibrane systems and systems of unstable D-branes in Type II superstring theory are investigated using the formalism of superconnections. The low-energy open string dynamics is shown to be probed by generalized Dirac operators. The corresponding index theorems are used to compute the chiral gauge anomalies in these systems, and hence their gravitational and Ramond-Ramond couplings. A spectral action for the generalized Dirac operators is also computed and shown to exhibit precisely the expected processes of tachyon condensation on the brane worldvolumes. The Chern-Simons couplings are thereby shown to be naturally related to Fredholm modules and bivariant K-theory, confirming the expectations that D-brane charge is properly classified by K-homology.

Szabó, R J

2001-01-01

191

Pressure gauge  

International Nuclear Information System (INIS)

The pressure gauge bar has the same outer diameter as the fuel elements and can be moved between the partly fixed and elastic spacers of the grid. The inner part of the pressure gauge bar is provided with a transverse beam which is connected with a strain gauge and has a bolt penetrating the clad of the pressure gauge bar and touching the elastic spacer dimple. (DG)

1980-01-01

192

Anomalies, counterterms and the ${\\cal N} =0$ Polchinski-Strassler solutions  

CERN Document Server

The singularity structure of many IIB supergravity solutions asymptotic to $AdS_5 \\times S^5$ becomes clearer when one considers the full ten dimensional solution rather than the dimensionally reduced solution of gauged supergravity. It has been shown that all divergences in the gravitational action of the dimensionally reduced spacetime can be removed by the addition of local counterterms on the boundary. Here we attempt to formulate the counterterm action directly in ten dimensions for a particular class of solutions, the ${\\cal N} = 0$ Polchinski-Strassler solutions, which are dual to an ${\\cal N} =4$ SYM theory perturbed by mass terms for all scalars and spinors. This involves constructing the solution perturbatively near the boundary. There is a contribution to the Weyl anomaly from the mass terms (which break the classical conformal invariance of the action). The coefficient of this anomaly is reproduced by a free field calculation indicating a non-renormalisation theorem inherited from the ${\\cal N} =4...

Taylor-Robinson, M M

2001-01-01

193

Supersymmetric regulators and supercurrent anomalies  

International Nuclear Information System (INIS)

The supercurrent anomalies of the supercurrent deltasub(?) of the supersymmetric Yang-Mills theory in Wess-Zumino gauge are computed using the supersymmetric dimensional regulator of Siegel. It is shown that ?sub(?)deltasup(?) = 0 and deltasub(?)deltasup(?) unequal 0 in agreement with an earlier calculation based on the Adler-Rosenberg method. The problem of exhibiting the chiral anomaly and a regulator for local supersymmetry suggests that the interpretation of dimensional reduction in component language is incomplete. (orig.)

1980-01-01

194

Brane boxes, anomalies, bending, and tadpoles  

International Nuclear Information System (INIS)

Certain classes of chiral four-dimensional gauge theories may be obtained as the world volume theories of D5-branes are suspended between networks of NS5-branes, the so-called brane box models. In this paper, we derive the stringy consistency conditions placed on these models, and show that they are equivalent to an anomaly cancellation of the gauge theories. We derive these conditions in the orbifold theories which are T dual to the elliptic brane box models. Specifically, we show that the expression for tadpoles for unphysical twisted Ramond-Ramond 4-form fields in the orbifold theory are proportional to the gauge anomalies of the brane box theory. Thus string consistency is equivalent to world volume gauge anomaly cancellation. Furthermore, we find additional cylinder amplitudes which give the ? functions of the gauge theory. We show how these correspond to bending of the NS-branes in the brane box theory. copyright 1998 The American Physical Society

1999-01-01

195

Vacuum Gauges  

Science.gov (United States)

This is a description for a learning module from Maricopa Advanced Technology Education Center. This PDF describes the module; access may be purchased by visiting the MATEC website. Semiconductor manufacturing equipment requires the use of many different types of vacuum gauges. Selection is based on range of process operations and production requirements. This MATEC module explores the theory and functionality of vacuum gauges and provides many examples of different types of gauges. The focus is on understanding the operating ranges and application constraints of each type of gauge. Mathematical equations are used to explain calibration, sensitivity, and overall operations of each type of gauge.

2012-11-28

196

Gravitational wave detector response in terms of spacetime Riemann curvature  

CERN Multimedia

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 unphysical metric perturbation has lead to a proliferation of false analogies and descriptions regarding how these detectors function, and true misunderstandings of the physical character of gravitational waves. Here we provide a fully physical and gauge invariant description of the response of a wide class of gravitational wave detectors in terms of the Riemann curvature, the physical quantity that describes gravitational phenomena in general relativity. In the limit of high frequency gravitational waves, the Riemann curvature...

Koop, Michael J

2013-01-01

197

Ebstein's Anomaly  

Science.gov (United States)

... may be reprinted for personal, noncommercial use only. Ebstein's anomaly By Mayo Clinic staff Original Article: http://www.mayoclinic.com/health/ebsteins-anomaly/DS00805 Definition Symptoms Causes Risk factors Complications Preparing ...

198

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

1977-01-01

199

Localized Fermions and Anomaly Inflow via Deconstruction  

CERN Multimedia

We study fermion localization in gauge theory space. We consider four dimensional product gauge groups in which light chiral fermions transform under different gauge factors of the product group. This construction provides a suppression of higher dimensional operators. For example, it can be used to suppress dangerous proton decay operators. The anomalies associated with the light chiral fermions are compensated by Wess-Zumino terms, which in the continuum limit reproduce the five dimensional Chern-Simons term.

Skiba, W; Skiba, Witold; Smith, David

2002-01-01

200

Anomaly constraints on nonlinear sigma models  

International Nuclear Information System (INIS)

[en] Anomalies in nonlinear sigma models can sometimes be canceled by local counterterms. The authors show that these counterterms have a simple topological interpretation, and that the requirements for anomaly cancellation can be easily understood in terms of 't Hooft's anomaly matching conditions. The authors exhibit the anomaly cancellation on homogeneous spaces G/H and on general riemannian manifolds M. They include external gauge fields on the manifolds and derive the generalized anomaly-cancellation conditions. Finally, they discuss the implications of this work for superstring theories

1989-01-01

 
 
 
 
201

Covariant anomalies and Hawking radiation from charged rotating black strings in anti-de Sitter spacetimes  

International Nuclear Information System (INIS)

Motivated by the success of the recently proposed method of anomaly cancellation to derive Hawking fluxes from black hole horizons of spacetimes in various dimensions, we have further extended the covariant anomaly cancellation method shortly simplified by Banerjee and Kulkarni to explore the Hawking radiation of the (3+1)-dimensional charged rotating black strings and their higher dimensional extensions in anti-de Sitter spacetimes, whose horizons are not spherical but can be toroidal, cylindrical or planar, according to their global identifications. It should be emphasized that our analysis presented here is very general in the sense that the determinant of the reduced (1+1)-dimensional effective metric from these black strings need not be equal to one (?(-g)?1). Our results indicate that the gauge and energy-momentum fluxes needed to cancel the (1+1)-dimensional covariant gauge and gravitational anomalies are compatible with the Hawking fluxes. Besides, thermodynamics of these black strings are studied in the case of a variable cosmological constant.

2008-03-27

202

Covariant anomalies and Hawking radiation from charged rotating black strings in anti-de Sitter spacetimes  

Energy Technology Data Exchange (ETDEWEB)

Motivated by the success of the recently proposed method of anomaly cancellation to derive Hawking fluxes from black hole horizons of spacetimes in various dimensions, we have further extended the covariant anomaly cancellation method shortly simplified by Banerjee and Kulkarni to explore the Hawking radiation of the (3+1)-dimensional charged rotating black strings and their higher dimensional extensions in anti-de Sitter spacetimes, whose horizons are not spherical but can be toroidal, cylindrical or planar, according to their global identifications. It should be emphasized that our analysis presented here is very general in the sense that the determinant of the reduced (1+1)-dimensional effective metric from these black strings need not be equal to one ({radical}(-g){ne}1). Our results indicate that the gauge and energy-momentum fluxes needed to cancel the (1+1)-dimensional covariant gauge and gravitational anomalies are compatible with the Hawking fluxes. Besides, thermodynamics of these black strings are studied in the case of a variable cosmological constant.

Peng Junjin [College of Physical Science and Technology, Central China Normal University, Wuhan, Hubei 430079 (China); Wu Shuangqing [College of Physical Science and Technology, Central China Normal University, Wuhan, Hubei 430079 (China)], E-mail: sqwu@phy.ccnu.edu.cn

2008-03-27

203

Global anomalies and algebraic topology  

International Nuclear Information System (INIS)

[en] The algebraic topology aspect of the global pure gauge anomaly calculation is investigated. In particular, the use of a cohomology sequence clarifies the method initiated by Witten [Nucl. Phys. 223, 422, 433 (1983)] and Elitzur and Nair [Nucl. Phys. B 243, 205 (1984)]. Examples in SU(N), Sp(N), and SO(N) are discussed

1988-01-01

204

Relationship between Hawking radiation and gravitational anomalies.  

Science.gov (United States)

We show that in order to avoid a breakdown of general covariance at the quantum level the total flux in each outgoing partial wave of a quantum field in a black hole background must be equal to that of a (1+1)-dimensional blackbody at the Hawking temperature. PMID:16090602

Robinson, Sean P; Wilczek, Frank

2005-06-30

205

Gravitational Waves from Gravitational Collapse  

Directory of Open Access Journals (Sweden)

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.

New Kimberly C.B.

2003-01-01

206

On Holographic Weyl Anomaly  

CERN Document Server

We use the relation between certain diffeomorphisms in the bulk and Weyl transformations on the boundary to build the conformal structure of the metric in the presence of matter in the bulk. We explicitly obtain the conformal anomaly in any spacetime dimension d in a holographic frame work in the case of gravity coupled to the scalar fields. This way we also provide a holographic construction of the bulk spacetime metric and of the matter fields in the bulk of this spacetime out of sources that are related to conformal field theory data. With the latter, we produce an asymptotic expansion of the bulk fields and scalar fields near the boundary in terms of spacetime dimension in the context of the AdS/CFT correspondence. We work out both the gravitational and matter conformal anomalies of the boundary theory as a coefficient of the infrared logarithmic divergence that appears in the on-shell action.

Mir, Mozhgan

2013-01-01

207

Gauge glass  

International Nuclear Information System (INIS)

The fundamental laws of nature may be truely random, or they may be so complicated that a random description is adequate. With this philosophy we examine various ways in which a lattice gauge theory (at the Planck scale) can be generalized. Without here giving up a regular lattice structure (which we really ought to do) we consider two generalizations. Making the action (quenched) random has the effect that the gauge group tends to break down and some gauge bosons become massive, unless the gauge group has special properties: no noncentral corners in the geometry of conjugacy classes and furthermore a connected center. Making the concept of gauge transformation more general has a symmetry breaking effect for groups with outer automorphisms. A study of SU5-breaking in the context of the first breakdown mechanism (D. Bennett, E. Buturovic and H. B. Nielsen) is shortly reviewed. (orig.)

1984-01-01

208

Harmonic superspace formalism and the consistent chiral anomaly  

Energy Technology Data Exchange (ETDEWEB)

The harmonic superspace formalism has been used to construct the consistent chiral anomaly in N = 1, d = 6 supersymmetric Yang-Mills thoery. The expressions of the gauge anomaly ..delta../sub s//sup phi/ and of the supersymmetric anomaly ..delta../sub SUSY//sup phi/ are given together with the consistent condition. 7 refs.

Li, W.

1986-08-01

209

Non-topological anomalies and Wess-Zumino effective action  

International Nuclear Information System (INIS)

The uniqueness of the full non-Abelian anomaly including the terms additional to the usual Bardeen anomaly is proved within gauge invariant perturbation theory. The resulting effective Wess-Zumino Lagrangian describes both normal and abnormal parity progresses. The slope parameter shown to be uniquely determined by the anomaly. (author)

1985-01-01

210

Duality with gauge singlets  

International Nuclear Information System (INIS)

We demonstrate how gauge singlets can be used to find new examples of Kutasov duality (i.e. where the matching of the dual theories relies on a non-zero superpotential) in N = 1 SU(N) SQCD with FQ flavours of quark and multiple generations of adjoints, or antisymmetrics, or symmetrics. The role of the singlets is to simplify greatly the truncation of the chiral ring whilst maintaining an R-symmetry, and at the same time allowing an unambiguous identification of the elementary mesons of the magnetic theory. The dual theories satisfy all the usual tests, including the highly non-trivial 't Hooft anomaly matching conditions.

2009-01-01

211

Dynamical cosmic strings from a gauge theory of gravity  

Energy Technology Data Exchange (ETDEWEB)

A new dynamical realization of O(5) gauge Euclidean gravity is proposed and shown to possess topologically nontrivial features, cosmic-string flux tubes and dark-matter solitons, of a purely gravitational origin (no Higgs particle needed).

Furlong, R.C.

1988-09-15

212

Dynamical cosmic strings from a gauge theory of gravity  

International Nuclear Information System (INIS)

A new dynamical realization of O(5) gauge Euclidean gravity is proposed and shown to possess topologically nontrivial features, cosmic-string flux tubes and dark-matter solitons, of a purely gravitational origin (no Higgs particle needed)

1988-09-15

213

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.)

1982-01-01

214

Gauge invariant composite operators of QED in the exact renormalization group formalism  

CERN Multimedia

Using the exact renormalization group (ERG) formalism, we study the gauge invariant composite operators in QED. Gauge invariant composite operators are introduced as infinitesimal changes of the gauge invariant Wilson action. We examine the dependence on the gauge fixing parameter of both the Wilson action and gauge invariant composite operators. After defining ``gauge fixing parameter independence,'' we show that any gauge independent composite operators can be made ``gauge fixing parameter independent'' by appropriate normalization. As an application, we give a concise but careful proof of the Adler-Bardeen non-renormalization theorem for the axial anomaly in an arbitrary covariant gauge by extending the original proof by A. Zee.

Sonoda, Hidenori

2013-01-01

215

Gauge boson mass without a Higgs field: a simple model  

Energy Technology Data Exchange (ETDEWEB)

A simple, anomaly-free chiral gauge theory can be perturbatively quantized and renormalized in such a way as to generate fermion and gauge boson masses. This development exploits certain freedoms inherent in choosing the unperturbed Lagrangian and in the renormalization procedure. Apart from its intrinsic interest, such a mechanism might be employed in electroweak gauge theory to generate fermion and gauge boson masses without a Higgs sector. 38 refs.

Nicholson, A.F. [Australian National Univ., Canberra, ACT (Australia). Dept. of Theoretical Physics; Kennedy, D.C. [Florida Univ., Gainesville, FL (United States). Dept. of Physics

1997-02-01

216

Gauge Boson Mass Without a Higgs Field A Simple Model  

CERN Document Server

A simple, anomaly-free chiral gauge theory can be perturbatively quantized and renormalized in such a way as to generate fermion and gauge boson masses. This development exploits certain freedoms inherent in choosing the unperturbed Lagrangian and in the renormalization procedure. Apart from its intrinsic interest, such a mechanism might be employed in electroweak gauge theory to generate fermion and gauge boson masses without a Higgs sector.

Nicholson, A F; Nicholson, Angus F.; Kennedy, Dallas C.

1997-01-01

217

Gauge boson mass without a Higgs field: a simple model  

International Nuclear Information System (INIS)

A simple, anomaly-free chiral gauge theory can be perturbatively quantized and renormalized in such a way as to generate fermion and gauge boson masses. This development exploits certain freedoms inherent in choosing the unperturbed Lagrangian and in the renormalization procedure. Apart from its intrinsic interest, such a mechanism might be employed in electroweak gauge theory to generate fermion and gauge boson masses without a Higgs sector. 38 refs.

1997-01-01

218

Gravitational waves  

International Nuclear Information System (INIS)

The development of detectors for gravitational radiation has never been a more active field than it is today. Bar detectors are improving and forming an observing network, and by end of 1989, four groups around the world will have proposed to their funding bodies the construction of large-scale laser interferometric gravitational wave detectors. I shall review the reasons for the current optimism about detecting gravitational waves, the theory of their sources, and the science that is likely to come rom this field in the next decade.

1989-01-01

219

Chiral Anomalies In Field Theories  

CERN Document Server

The role of the contribution from the fermion mass term in the axial vector Ward identity in generating the U(1) axial anomaly, both local and global, is elucidated. Gauge invariance requires the fermion to decouple from the gauge field if it is very heavy. This identifies the Adler-Bell-Jackiw (ABJ) anomaly with the asymptotic limit of the sign reversed mass term. In an instanton background, the chiral limit $(m = 0)$ of the mass term does not vanish but consists of contributions from fermion zero modes. Space time integral of these zero mode contributions exactly cancels, thanks to the Atiyah-Singer index theorem, the integral of the ABJ anomaly and suggests that the Jacobian for global U(1) chiral transformation is trivial even in an instanton background. This can be realised in the representation of the fermion partition function in a Weyl basis. The resolution of the strong CP problem is thus achieved in an axionless physical world. In chiral gauge theories the fermion partition function admits of a gaug...

Banerjee, H

2000-01-01

220

Black holes in large N gauge theories  

International Nuclear Information System (INIS)

Generalizations of the AdS/CFT correspondence provide a dual Yang-Mills formulation of gravitational physics. In these lectures we investigate the gauge theoretic description of black holes in AdS5 x S5 and in backgrounds dual to classes of confining gauge theories. We are motivated by the hope that the Yang-Mills description of black holes will shed new light on long-standing puzzles involving these objects.

2006-11-07

 
 
 
 
221

Gravitation Research.  

Science.gov (United States)

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 source...

D. J. Muehlner D. K. Owens N. A. Pierre R. Weiss R. L. Benford

1972-01-01

222

Gauged Inflation  

CERN Multimedia

Based on thermal equilibrium between the vacuum and its relevant excitations a model for cosmic inflation is presented. Due to a vacuum dominating, U(1) gauged inflaton field an inflationary regime can be reached without explicitly imposing slow-roll conditions. Thereby, nontrivial euclidean BPS saturation of the inflaton bans gravity from the field equations and masquerades the gauge symmetry as a $Z_{N+1}$ symmetry at the point where thermal equilibrium breaks down. Solving the vacuum dynamics of the gauge field in the inflaton background in the spirit of a Born-Oppenheimer approximation, a temperature dependent cosmological constant $\\La=\\La(T)$ is obtained. The $T$ dependence of $\\La$ competes with the black body radiation of the (massive) gauge field during cosmic expansion. This leads to (initial condition independent) inflation at some critical value of the inflaton amplitude. The model allows for a closed, noncollapsing universe with Planckian initial density, and hence it resolves the flatness proble...

Hofmann, Ralf; Hofmann, Ralf; Keil, Mathias Th.

2002-01-01

223

Anomaly-free sets of fermions  

Energy Technology Data Exchange (ETDEWEB)

We present new techniques for finding anomaly-free sets of fermions. Although the anomaly cancellation conditions typically include cubic equations with integer variables that cannot be solved in general, we prove by construction that any chiral set of fermions can be embedded in a larger set of fermions which is chiral and anomaly-free. Applying these techniques to extensions of the Standard Model, we find anomaly-free models that have arbitrary quark and lepton charges under an additional U(1) gauge group.

Batra, Puneet; /Argonne; Dobrescu, Bogdan A.; /Fermilab; Spivak, David; /UC, Berkeley, Math. Dept.

2005-10-01

224

Gravitational waves from gravitational collapse  

Energy Technology Data Exchange (ETDEWEB)

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.

Fryer, Christopher L [Los Alamos National Laboratory; New, Kimberly C [Los Alamos National Laboratory

2008-01-01

225

Gravitational Waves from Gravitational Collapse  

Directory of Open Access Journals (Sweden)

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.

Chris L. Fryer; Kimberly C.B. New

2011-01-01

226

The Pioneer Anomaly  

Directory of Open Access Journals (Sweden)

Full Text Available 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 × 10–9 Hz/s. Ultimately, the drift was interpreted as a constant sunward deceleration of each particular spacecraft at the level of aP = (8.74 ± 1.33) × 10–10 m/s2. 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 anomaly 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-extended set of radio-metric Doppler data for both spacecraft in conjunction with the newly available complete record of their telemetry files and a large archive of original project documentation. As the new study is yet to report its findings, this review provides the necessary background for the new results to appear in the near future. In particular, we provide a significant amount of information on the design, operations and behavior of the two Pioneers during their entire missions, including descriptions of various data formats and techniques used for their navigation and radio-science data analysis. As most of this information was recovered relatively recently, it was not used in the previous studies of the Pioneer anomaly, but it is critical for the new investigation.

Slava G. Turyshev; Viktor T. Toth

2010-01-01

227

Ambiguities in the gravitational correction of quantum electrodynamics running coupling  

CERN Multimedia

We verify that quadratic divergences stemming from gravitational corrections to QED which have been conjectured to lead to asymptotic freedom near Planck scale are arbitrary (regularization dependent) and compatible with zero. Moreover we explicitly show that such arbitrary term contributes to the beta function of QED in a gauge dependent way in the gravitational sector.

Felipe, J C C; Brito, L C T; Sampaio, Marcos; Nemes, M C

2012-01-01

228

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)

1985-01-01

229

Two potentials, one gauge group. A possible geometrical motivation  

Energy Technology Data Exchange (ETDEWEB)

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.

Doria, R.M.; Pombo, C.

1986-12-11

230

Two potentials, one gauge group: a possible geometrical motivation  

International Nuclear Information System (INIS)

[en] 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

1986-12-11

231

Phase factors, point-splitting regularisation and chiral anomalies  

Energy Technology Data Exchange (ETDEWEB)

A method is proposed to construct the path-independent form of phase factors pertaining to non-abelian gauge theories. It is found that the original form of the phase factor, as envisaged by Schwinger, is reproduced for a straight path. As an illustration of its use this work is applied, within the framework of point-splitting regularisation, to obtain the familiar axial anomaly in a pure vector gauge theory. Subtleties associated with the treatment of the vector gauge current are also discussed. Finally, the scheme of computations is employed to derive the covariant and consistent anomalies in a non-abelian chiral gauge theory in arbitrary even dimensions. (orig.)

Banerjee, R.; Banerjee, H.

1988-06-01

232

Aging gauge  

Energy Technology Data Exchange (ETDEWEB)

An aging gauge comprising a container having a fixed or a variable sized t opening with a cap which can be opened to control the sublimation rate of a thermally sublimational material contained within the container. In use, the aging gauge is stored with an item to determine total heat the item is subjected to and also the maximum temperature to which the item has been exposed. The aging gauge container contains a thermally sublimational material such as naphthalene or similar material which has a low sublimation rate over the temperature range from about 70.degree. F. to about 160.degree. F. The aging products determined by analyses of a like item aged along with the aging gauge for which the sublimation amount is determined is employed to establish a calibration curve for future aging evaluation. The aging gauge is provided with a means for determining the maximum temperature exposure (i.e., a thermally indicating material which gives an irreversible color change, Thermocolor pigment). Because of the relationship of doubling reaction rates for increases of 10.degree. C., equivalency of item used in accelerated aging evaluation can be obtained by referring to a calibration curve depicting storage temperature on the abscissa scale and multiplier on the ordinate scale.

Betts, Robert E. (Huntsville, AL); Crawford, John F. (Huntsville, AL)

1989-01-01

233

The Pioneer Anomaly  

CERN Multimedia

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...

Turyshev, Slava G

2010-01-01

234

Differential Renormalization of Gauge Theories  

CERN Document Server

The scope of constrained differential renormalization is to provide renormalized expressions for Feynman graphs, preserving at the same time the Ward identities of the theory. It has been shown recently that this can be done consistently at least to one loop for abelian and non-abelian gauge theories. We briefly review these results, evaluate as an example the gluon selfenergy in both coordinate and momentum space, and comment on anomalies.

del Águila, F

1998-01-01

235

??????????????? ???????????????? 25+ Gauge ? ??????? ????????? ? ??????????-????? ??????????? ???????????  

Directory of Open Access Journals (Sweden)

Full Text Available Purpose: The features and results of the surgical treatment of idiopathic macular holes with application of modern microinvasive 25+ Gauge chromovitrectomy and endovitriol dye BrilliantBlue G have been studied in the article. Materials and methods: The surgical treatment of 45 patients with macular holes aged 58,4 +/-10,3 years has been performed. Results: Microinvasive 25+Gauge chromovitrectomy with application of endovitriol dye BrilliantBlueG allows to achieve high anatomic and functional results in treatment of idiopathic macular holes in the early and remote periods of supervision. Intraoperative and postoperative complications have been analyzed with anatomic and functional results. Conclusion: It has been revealed that modern microinvasive 25+ Gauge chromovitrectomy with application of endovitriol dye BrilliantBlueG makes the surgery easier and more effective.

??????? B.C.; ????? ?.?.

2013-01-01

236

Gauge fields  

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.).

1978-06-17

237

Light-induced gauge fields for ultracold atoms  

CERN Document Server

Gauge fields are central in our modern understanding of physics at all scales. At the highest energy scales known, the microscopic universe is governed by particles interacting with each other through the exchange of gauge bosons. At the largest length scales, our universe is ruled by gravity, whose gauge structure suggests the existence of a particle - the graviton - that mediates the gravitational force. At the mesoscopic scale, solid-state systems are subjected to gauge fields of different nature: materials can be immersed in external electromagnetic fields, but they can also feature emerging gauge fields in their low-energy description. In this review, we focus on another kind of gauge field: those engineered in systems of ultracold neutral atoms. In these setups, atoms are suitably coupled to laser fields that generate effective gauge potentials in their description. Neutral atoms "feeling" laser-induced gauge potentials can potentially mimic the behavior of an electron gas subjected to a magnetic field,...

Goldman, N; Ohberg, P; Spielman, I B

2013-01-01

238

Cosmic Microwave Background anisotropies from second order gravitational perturbations  

CERN Multimedia

This paper presents a complete analysis of the effects of second order gravitational perturbations on Cosmic Microwave Background anisotropies, taking explicitly into account scalar, vector and tensor modes. We also consider the second order perturbations of the metric itself obtaining them, for a universe dominated by a collision-less fluid, in the Poisson gauge, by transforming the known results in the synchronous gauge. We discuss the resulting second order anisotropies in the Poisson gauge, pointing out the potentially most relevant effects.

Mollerach, S; Mollerach, Silvia; Matarrese, Sabino

1997-01-01

239

Studies on broken symmetry of gravitational field  

Energy Technology Data Exchange (ETDEWEB)

The concept of spontaneous symmetry breaking has proved to be extraordinarily fruitful in many areas of physics and we consider it worthwhile to try to incorporate it into gravitation. It is suggested that the same symmetry breaking mechanism is responsible for breaking a unified gauge theory into strong, weak, and electromagnetic interactions.

Oh, K.J.; Kim, J.Y. (Chonnam National Univ., Kwangju (Republic of Korea))

1980-01-01

240

Gravitational Techniwaves  

CERN Document Server

We investigate the production and possible detection of gravitational waves stemming from the electroweak phase transition in the early universe in models of minimal walking technicolor. In particular we discuss the two possible scenarios in which one has only one electroweak phase transition and the case in which the technicolor dynamics allows for multiple phase transitions.

Jarvinen, Matti; Sannino, Francesco

2009-01-01

 
 
 
 
241

Gravitational Baryogenesis  

Energy Technology Data Exchange (ETDEWEB)

We show that a gravitational interaction between the derivative of the Ricci scalar curvature and the baryon-number current dynamically breaks CPT in an expanding universe and, combined with baryon-number-violating interactions, can drive the universe towards an equilibrium baryon asymmetry that is observationally acceptable.

Davoudias, Hooman; Kitano, Ryuichiro; Kribs, Graham D.; Murayama, Hitoshi; Steinhardt, Paul J.

2004-03-02

242

Relation between anomaly in type-I superstring and anomaly in its effective theory  

International Nuclear Information System (INIS)

We explicitly calculate the hexagon and heptagon (covariant) gauge anomaly including the precise numerical coefficients in type-I open superstring. The calculation is performed by using the Pauli-Villars regularization on the basis of the stringy Ward identity, which is an assumption weaker than the cancelled propagator argument. We show that the anomalies in the effective theory are realized as the zero slope limit (?' ? 0) of the string anomalies in a very non-trivial way in the present calculational scheme. This non-trivial realization in higher point (n ? 8) anomalies is also discussed. (author)

1987-01-01

243

Gravitation on a Spherically Symmetric Metric Manifold  

Directory of Open Access Journals (Sweden)

Full Text Available The usual interpretations of solutions for Einstein's gravitational field satisfying the spherically symmetric condition contain anomalies that are not mathematically permissible. It is shown herein that the usual solutions must be modified to account for the intrinsic geometry associated with the relevant line elements.

Crothers S. J.

2007-01-01

244

Peters' anomaly.  

UK PubMed Central (United Kingdom)

While conducting medical aid in Mozambique, a 41 year old African male presented to our eye clinic complaining of visual impairment. The male was found to have Peters' anomaly type 2, a rare congenital ocular malformation leading to sensory amblyopia and glaucoma.

Sault RW; Sheridan J

2013-01-01

245

Gravitational Lenses  

CERN Multimedia

The purpose of these lecture notes is to describe the gravitational lens effects in different astrophysical contexts. These notes are voluntarily focused on the fundamental mechanisms and the basic concepts that are useful to describe these effects. The observational consequences are presented in more details in accompanying notes by Y. Mellier. The content of these notes is the following. In the first section describe of the basic mechanisms of gravitational lenses, techniques and approximations that are usually employed. The second section is devoted to the case of a very simple deflector, a point-like mass distribution. This corresponds to microlensing events in which the deflectors are compact objects of a fraction of a solar mass that may populate the halo of our Galaxy. The last two sections are devoted to cosmological applications. After a presentation of the geometrical quantities that are specific to cosmology, I will present the various phenomena that can be observed in this context. Finally I descr...

Bernardeau, F

1999-01-01

246

Fermions on curved spaces, symmetries, and quantum anomalies  

International Nuclear Information System (INIS)

Investigating the Dirac equation in curved backgrounds we point out the role of the Killing-Yano tensors in the construction of the Dirac-type operators. The gravitational and axial anomalies are studied for generalized Euclidean Taub-Newman-Unti-Tamburino (Taub-NUT) metrics, which admit hidden symmetries analogous to the Runge-Lenz vector of the Kepler-type problem. The generalized Taub-NUT metrics exhibit in general gravitational anomalies. Using the Atiyah-Patodi-Singer index theorem for manifolds with boundaries, it is shown that these metrics make no contribution to the axial anomaly.

2007-04-23

247

Spin and orbital angular momentum of the tensor gauge field  

CERN Multimedia

Following the recent studies of the trickiness in spin and orbital angular momentum of the vector gauge fields, we perform here a parallel analysis for the tensor gauge field, which has certain relation to gravitation. Similarly to the vector case, we find a nice feature that after removing all gauge degrees of freedom the angular momentum of the tensor gauge field vanishes for a stationary system. This angular momentum also shows a one-parameter invariance over the infinitely many ways of complete gauge fixing for the tensor field. The tensor gauge coupling, however, does exhibit a critical difference from the vector gauge coupling that it may induce intrinsic interaction terms into the spatial translation and rotation generators, leaving none of the ten Poincar\\'e generators interaction-free.

Chen, Xiang-Song; Murchadha, Niall Ó

2011-01-01

248

Chiral anomaly of antisymmetric tensor fields  

International Nuclear Information System (INIS)

[en] For antisymmetric tensor gauge fields of rank 2n-1 coupled to gravity in 4n dimensions it is shown that the symmetry under duality rotations is broken by quantum effects. The anomaly is related to a local version of the signature index theorem. The zeta-function technique, Fujikawa's method, and the stochastic regularization scheme are discussed

1988-03-15

249

Brane boxes, anomalies, bending, and tadpoles  

Energy Technology Data Exchange (ETDEWEB)

Certain classes of chiral four-dimensional gauge theories may be obtained as the world volume theories of D5-branes are suspended between networks of NS5-branes, the so-called brane box models. In this paper, we derive the stringy consistency conditions placed on these models, and show that they are equivalent to an anomaly cancellation of the gauge theories. We derive these conditions in the orbifold theories which are {ital T} dual to the elliptic brane box models. Specifically, we show that the expression for tadpoles for unphysical twisted Ramond-Ramond 4-form fields in the orbifold theory are proportional to the gauge anomalies of the brane box theory. Thus string consistency is equivalent to world volume gauge anomaly cancellation. Furthermore, we find additional cylinder amplitudes which give the {beta} functions of the gauge theory. We show how these correspond to bending of the NS-branes in the brane box theory. {copyright} {ital 1998} {ital The American Physical Society}

Leigh, R.G.; Rozali, M. [Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)

1999-01-01

250

The ? transformation and gravitational copies  

International Nuclear Information System (INIS)

An Abelian symmetry already considered by Einstein with respect to his asymmetrical field theories is related to the gravitational and gauge field copy phenomenon. It is shown that gauge field copies arise out of a straightforward generalization of the ? - map. The connection between Einstein's work on the ?-transformation and the copy phenomenon is obtained with the help of the Frobenius Theorem on the existence of foliations on a differentiable manifold. A problem like the one above is usually treated within the language of (intrinsic) Differential Geometry; General Relativity and classical unified field theories are traditionally developed in a classical style, that gap, a long introduction is prepared where the same structures are studied from the traditional and from the more recent point of view. (author)

1984-01-01

251

The tale of gravitational sphaleron  

CERN Multimedia

Type I string theory can be dimensionally reduced on group manifolds. The compactification on $S^3\\times S^3$ leads to the N=4 gauged SU(2)$\\times$SU(2) supergravity in four dimensions, which admits the BPS monopole type non-Abelian vacuum. The reduction on $S^3\\times AdS_3$ gives the Euclidean N=4 gauged SU(2)$\\times$SU(1,1) supergravity admitting a globally regular supersymmetric non-Abelian background. The latter can be analytically continued to the Lorentzian sector, which gives the regular, unstable particle-like configuration known as gravitational sphaleron. When lifted to D=10, the Euclidean vacuum describes a deformation of the D1--D5 brane system.

Volkov, M S

2000-01-01

252

Gauge mechanics  

CERN Document Server

This book presents in a unified way modern geometric methods in analytical mechanics based on the application of fibre bundles, jet manifold formalism and the related concept of connection. Non-relativistic mechanics is seen as a particular field theory over a one-dimensional base. In fact, the concept of connection is the major link throughout the book. In the gauge scheme of mechanics, connections appear as reference frames, dynamic equations, and in Lagrangian and Hamiltonian formalisms. Inertial forces, energy conservation laws and other phenomena related to reference frames are analyzed;

Mangiarotti, L

1998-01-01

253

Quantum 3D Tensionless String in Light-cone Gauge  

CERN Multimedia

We discuss the quantization of a tensionless closed string in light-cone gauge. It is known that by using a Hamiltonian BRST scheme the tensionless p-branes have no Lorentz anomaly in any space-time dimensions and no anomaly of space-time conformal symmetry in two dimensions. In this paper, we show that tensionless 3d strings in light-cone gauge also have no anomaly of space-time conformal symmetry. We also study the spectrum of a tensionless 3d closed string.

Murase, Kenta

2013-01-01

254

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)

1983-06-22

255

New insight into BRST anomalies in superstring theory  

International Nuclear Information System (INIS)

[en] 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.))

1994-08-22

256

Gravitational energy and cosmic acceleration  

CERN Multimedia

Cosmic acceleration is explained quantitatively, as an apparent effect due to gravitational energy differences that arise in the decoupling of bound systems from the global expansion of the universe. "Dark energy" is a misidentification of those aspects of gravitational energy which by virtue of the equivalence principle cannot be localised, namely gradients in the energy due to the expansion of space and spatial curvature variations in an inhomogeneous universe. A new scheme for cosmological averaging is proposed which solves the Sandage-de Vaucouleurs paradox. Concordance parameters fit supernovae luminosity distances, the angular scale of the sound horizon in the CMB anisotropies, and the effective comoving baryon acoustic oscillation scale seen in galaxy clustering statistics. Key observational anomalies are potentially resolved, and unique predictions made, including a quantifiable variance in the Hubble flow below the scale of apparent homogeneity.

Wiltshire, David L

2007-01-01

257

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.).

1985-01-01

258

Gaugeon formalism for spin-3/2 Rarita-Schwinger gauge field  

International Nuclear Information System (INIS)

[en] We apply the BRST symmetric gaugeon formalism to the spin-3/2 Rarita-Schwinger gauge field. To this time, this formalism has been developed for quantum electrodynamics and the Yang-Mills gauge field. The theory admits a quantum gauge transformation by which we can shift the gauge fixing parameter. The quantum gauge transformation does not change the BRST charge. Thus, the physical Hilbert space is trivially independent of the gauge fixing parameter. By virtue of the BRST symmetry, the physical Hilbert space is still well-defined when we incorporate the interaction with the Ricci flat background gravitational field. (author)

2000-01-01

259

Non-perturbative Equivalences In Gauge Theories With Global Symmetries In The Limit Of Large N  

CERN Multimedia

The thesis is devoted to the study of various types of equivalences in large N gauge theories. We are specifically interested in theories whose dynamics is not constrained by supersymmetry or conformal invariance, and we consider theories both at zero and at finite temperature. Specific examples include equivalences between gauge theories, gauge theories and matrix models, and between gauge theories and gravitational theories. The use of lattice regularization for zero temperature gauge theories and effective hydrodynamic description for finite temperature gauge theories made it possible to find generic equivalences which do not rely on any sort of small-parameter expansion.

Kovtun, P

2004-01-01

260

On The 5D Extra-Force according to Basini-Capozziello-Ponce De Leon Formalism and three important features: Chung-Freese Superluminal BraneWorld,Strong Gravitational Fields and the Pioneer Anomaly  

CERN Document Server

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 ...

Loup, Fernando

2007-01-01

 
 
 
 
261

Gravitational helioseismology?  

CERN Multimedia

The magnitudes of the external gravitational perturbations associated with the normal modes of the Sun are evaluated to determine whether these solar oscillations could be observed with the proposed Laser Interferometer Space Antenna (LISA), a network of satellites designed to detect gravitational radiation. The modes of relevance to LISA---the l=2, low-order p, f and g-modes---have not been conclusively observed to date. We find that the energy in these modes must be greater than about 10^{30} \\rm{ergs} in order to be observable above the LISA detector noise. These mode energies are larger than generally expected, but are much smaller than the current observational upper limits. LISA may be confusion-limited at the relevant frequencies due to the galactic background from short-period white dwarf binaries. Present estimates of the number of these binaries would require the solar modes to have energies above about 10^{33} \\rm{ergs} to be observable by LISA.

Cutler, C; Cutler, Curt; Lindblom, Lee

1996-01-01

262

Gravitational decoherence  

CERN Multimedia

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...

Kok, P; Kok, Pieter; Yurtsever, Ulvi

2003-01-01

263

Non-Relativistic Limit of Dirac Equations in Gravitational Field and Quantum Effects of Gravity  

CERN Document Server

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...

Wu, N

2006-01-01

264

The Coulomb static gauge  

CERN Multimedia

The existence of gauge conditions involving second-order derivatives of potentials is not well known in classical electrodynamics. We introduce one of these gauges, the Coulomb static gauge, in which the scalar potential is given by the Coulomb static potential. We obtain an explicit expression for the associated vector potential and show how the scalar and vector potentials in this gauge yield the retarded electric and magnetic fields. We note the close relation between the proposed gauge and the temporal gauge.

Heras, Jose A

2008-01-01

265

Soft gauge algebras  

Energy Technology Data Exchange (ETDEWEB)

Gauge transformations whose algebra closes only modulo field dependent terms (soft gauge algebras) are studied in detail. The results are explicitly applied to a supersymmetric gauge theory, to gravity and to conformal gravity, all seen as gauge theories over x-space; the obvious applications to supergravity are pointed out. A consistency requirement for the gauge transformations of those fields which appear in the algebra is seen to rule out ''local translations'' as independent gauge transformations.

Sohnius, M.F.

1983-06-01

266

Gauge coupling variation in brane models  

International Nuclear Information System (INIS)

We consider the space-time variation of gauge couplings in brane-world models induced by the coupling to a bulk scalar field. A variation is generated by the running of the gauge couplings with energy and a conformal anomaly while going from the Jordan to the Einstein frame. We indicate that the one-loop corrections cancel implying that one obtains a variation of the fine structure constant by either directly coupling the gauge fields to the bulk scalar field or having bulk scalar field dependent Yukawa couplings. Taking into account the cosmological dynamics of the bulk scalar field, we constrain the strength of the gauge coupling dependence on the bulk scalar field and relate it to modifications of gravity at low energy.

2003-12-15

267

CPT violation and chiral lattice gauge theory  

CERN Document Server

This thesis is organized as follows: In Chapter 2, an overview of Euclidean fermions is given, paying special attention to the transformations of fermions. This chapter also contains a summary of local gauge transformations, chiral symmetry and the CPT theorem. In Chapter 3, the chiral gauge theory considered is introduced. In particular, the manifold and the gauge group are specified. In Chapter 4, the basic points of chiral lattice gauge theory are summarized. In Chapter 5, the resulting effective action on the lattice and its behavior under a CPT transformation are discussed. In Chapter 6, the effective action is found to be CPT noninvariant for arbitrary lattice spacing a. It is also shown that this anomaly does not vanish in the continuum limit.

Schimmel, J

2003-01-01

268

CPT violation and chiral lattice gauge theory  

International Nuclear Information System (INIS)

This thesis is organized as follows: In Chapter 2, an overview of Euclidean fermions is given, paying special attention to the transformations of fermions. This chapter also contains a summary of local gauge transformations, chiral symmetry and the CPT theorem. In Chapter 3, the chiral gauge theory considered is introduced. In particular, the manifold and the gauge group are specified. In Chapter 4, the basic points of chiral lattice gauge theory are summarized. In Chapter 5, the resulting effective action on the lattice and its behavior under a CPT transformation are discussed. In Chapter 6, the effective action is found to be CPT noninvariant for arbitrary lattice spacing a. It is also shown that this anomaly does not vanish in the continuum limit. (orig.)

2003-01-01

269

Gravitational decoherence  

International Nuclear Information System (INIS)

[en] 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. Although in principle observable, the current state of technology prohibits the experimental demonstration of the phase drift. Second, 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. Third, we study the interaction of coherent and squeezed gravitational waves with a qubit in uniform motion. Finally, we investigate the decoherence of an accelerating qubit in Minkowski spacetime due to the Unruh effect. In this case decoherence is not due to fluctuations in the metric, but instead is caused by coupling (which we model with a standard Hamiltonian) between the qubit and the thermal cloud of Unruh particles bathing it. When the accelerating qubit is entangled with a stationary partner, the decoherence should induce a corresponding loss in teleportation fidelity

2003-10-15

270

Finite gauge field theory and quantum gravity  

Energy Technology Data Exchange (ETDEWEB)

A quantum field theory which is Poincare invariant, gauge invariant, finite and unitary to all orders of perturbation theory is applied to quantum chromodynamics. Quantum gravity is finite and unitary to all orders of perturbation theory. The Bekenstein-Hawking entropy formula for a black hole is investigated in a conical Rindler space approximation to a black hole event horizon. A renormalization of the gravitational coupling constant is performed leading to a finite Bekenstein-Hawking entropy at the horizon. (author)

Moffat, J.W. [Toronto Univ., ON (Canada). Dept. of Physics

1999-07-01

271

Calculation of Newton's gravitational constant in infrared-stable Yang-Mills theories  

Energy Technology Data Exchange (ETDEWEB)

Newton's gravitational constant G is calculated in a class of scale-invariant gauge theories with an infrared fixed point. The sign of G depends on the coefficients in the renormalization-group ..beta.. function.

Zee, A.

1982-02-01

272

Demonstrating Gravitational Repulsion  

Directory of Open Access Journals (Sweden)

Full Text Available In previous papers we showed that a classical model of gravitation explains present gravitational phenomena. This paper deals with gravitational repulsion and it shows how it manifests in black holes and particle pair production. We also suggest a laboratory experiment to demonstrate gravitational repulsion.

Wagener P. C.

2010-01-01

273

Gaugino-assisted anomaly mediation  

International Nuclear Information System (INIS)

I present a model of supersymmetry breaking mediated through a small extra dimension. Standard model matter multiplets and a supersymmetry-breaking (or 'hidden') sector are confined to opposite four-dimensional boundaries while gauge multiplets live in the bulk. The hidden sector does not contain a singlet and the dominant contribution to gaugino masses is via anomaly-mediated supersymmetry breaking. Scalar masses get contributions from both anomaly mediation and a tiny hard breaking of supersymmetry by operators on the hidden-sector boundary. These operators contribute to scalar masses at one loop and in most of parameter space, their contribution dominates. Thus it is easy to make all squared scalar masses positive. As no additional fields or symmetries are required below the Planck scale, this is among the simplest working models of anomaly mediation. The gaugino spectrum is left untouched and the phenomenology of the model is roughly similar to anomaly mediated supersymmetry breaking with a universal scalar mass added. Finally, the main differences in the spectrum between this model and other approaches are identified. This talk is based on work [1] done in collaboration with David E. Kaplan.

2001-01-01

274

Gaugino-Assisted Anomaly Mediation  

International Nuclear Information System (INIS)

We present a model of supersymmetry breaking mediated through a small extra dimension. Standard model matter multiplets and a supersymmetry-breaking (or ''hidden'') sector are confined to opposite four-dimensional boundaries while gauge multiplets live in the bulk. The hidden sector does not contain a singlet and the dominant contribution to gaugino masses is via anomaly-mediated supersymmetry breaking. Scalar masses get contributions from both anomaly mediation and a tiny hard breaking of supersymmetry by operators on the hidden-sector boundary. These operators contribute to scalar masses at one loop and in most of parameter space, their contribution dominates. Thus it is easy to make all squared scalar masses positive. As no additional fields or symmetries are required below the Planck scale, we consider this the simplest working model of anomaly mediation. The gaugino spectrum is left untouched and the phenomenology of the model is roughly similar to anomaly mediated supersymmetry breaking with a universal scalar mass added. We identify the main differences in the spectrum between this model and other approaches. We also discuss mechanisms for generating the ? term and constraints on additional bulk fields. (author)

2000-01-01

275

Gravitational Chern-Simons Lagrangians and black hole entropy  

CERN Document Server

We analyze the problem of defining the black hole entropy when Chern-Simons terms are present in the action. Extending previous works, we define a general procedure, valid in any odd dimensions both for purely gravitational CS terms and for mixed gauge-gravitational ones. The final formula is very similar to Wald's original formula valid for covariant actions, with a significant modification. Notwithstanding an apparent violation of covariance we argue that the entropy formula is indeed covariant.

Bonora, Loriano; Prester, Predrag Dominis; Pallua, Silvio; Smoli?, Ivica

2011-01-01

276

Two-dimensional non-abelian bosonization in the presence of external gauge fields and gravity  

Energy Technology Data Exchange (ETDEWEB)

Two-dimensional non-abelian Bose-Fermi equivalence in the presence of two-dimensional background gauge and gravitational fields is discussed for the k>1 WZW model and fermions constrained through coupling to gauge fields which act as Lagrange parameters. The equivalence is shown to be valid only when the gravitational field can be decoupled, which occurs when the central charge coincides with that obtained from current algebra.

Redlich, A.N.; Schnitzer, H.J.

1987-07-23

277

New insight into BRST anomalies in superstring theory  

CERN Multimedia

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, 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 hierarchial relationship in the BRST anoamlies.

Fujiwara, T; Koseki, M; Kuriki, R; Tabei, T

1994-01-01

278

Determination of covariant Schwinger terms in anomalous gauge theories  

International Nuclear Information System (INIS)

A functional integral method is used to determine equal time commutators between the covariant currents and the covariant Gauss-law operators in theories which are affected by an anomaly. By using a differential geometrical setup we show how the derivation of consistent- and covariant Schwinger terms can be understood on an equal footing. We find a modified consistency condition for the covariant anomaly. As a by-product the Bardeen-Zumino functional, which relates consistent and covariant anomalies, can be interpreted as connection on a certain line bundle over all gauge potentials. Finally the commutator anomalies are calculated for the two- and four dimensional case. (Author) 13 refs

1991-01-01

279

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

1989-08-01

280

Supersymmetric gauge theories from string theory  

International Nuclear Information System (INIS)

[en] 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)

2005-01-01

 
 
 
 
281

Recent developments in the path integral approach to anomalies  

International Nuclear Information System (INIS)

After a brief summary of the path integral approach to anomalous identities, some of the recent developments in this approach are discussed. The topics discussed include (i) Construction of the effective action by means of the covariant current, (ii) Gauss law constraint in anomalous gauge theories, (iii) Path integral approach to anomalies in superconformal transformations, (iv) Conformal and ghost number anomalies in string theory in analogy with the instanton calculation, (v) Covariant local Lorentz anomaly and its connection with the mathematical construction of the consistent anomaly. (author)

1986-01-01

282

Tetrads, broken symmetries, and the gravitational constant  

Energy Technology Data Exchange (ETDEWEB)

Tetrads cause the breakdown of symmetry in gravitational theories. Their vacuum expected values reduce the symmetry of the vacuum from that of the action to what is global Poincare invariance at ordinary distances. Gravitational theories can be written in terms of rescaled fields in such a way that the Planck mass never appears. The rescaled fields are dimensionless, except for gauge fields and tetrads, both of which acquire the dimension of mass. The empirical distribution of energy throughout spacetime causes the tetrads to assume vacuum expected values of the order of the Planck mass, msub(p). Thus the gravitational constant, G=(h/2..pi..)c/msub(p)/sup 2/, may be viewed not as a fundamental constant, but as a mass scale that is dynamically determined by the large-scale structure of the universe. Generalized tetrads may also break internal symmetries.

Cahill, K.

1984-06-01

283

Schwinger model and its axial anomaly  

Energy Technology Data Exchange (ETDEWEB)

The Schwinger model (quantum electrodynamics with massless fermions in one spatial dimension) is solved, supposing that space is a circle. This clarifies aspects of the usual version of the model, where space is a line, without changing the physics. The Hamiltonian formalism is used. On a circle, an abelian gauge field has one physical degree of freedom, and the gauge covariant Dirac operator, which couples the fermions to this degree of freedom, exhibits spectral flow. The relationship between the spectral flow and the axial anomaly is explained. Some variants of the Schwinger model are also discussed.

Manton, N.S.

1985-01-01

284

On the localization of the gravitational energy  

Directory of Open Access Journals (Sweden)

Full Text Available Using a formalism introduced by Feynman, Deser, Grishchuk, Petrov and Popova, the pseudotensors, such as de.ned by Einstein, Tolman, Landau/Lifshitz and Møller, are expessed as gauge dependent tensors in a background space, as the gravitational energy-momentum tensor of Deser, Grishchuk, Petrov and Popova. Using a result obtained by Virbhadra for the energy density in the Reissner-Nordström spacetime, it is shown that the action of these gauge transformations on the above tensorial expressions is the same as the action of the coordinate transformations on the equivalent pseudotensorial expressions, meaning that these tensors can be set to zero at a point by a suitable choice of gauge transformation.

Pinto Neto N.; Trajtenberg P. I.

2000-01-01

285

On the localization of the gravitational energy  

Scientific Electronic Library Online (English)

Full Text Available Abstract in english Using a formalism introduced by Feynman, Deser, Grishchuk, Petrov and Popova, the pseudotensors, such as de.ned by Einstein, Tolman, Landau/Lifshitz and Møller, are expessed as gauge dependent tensors in a background space, as the gravitational energy-momentum tensor of Deser, Grishchuk, Petrov and Popova. Using a result obtained by Virbhadra for the energy density in the Reissner-Nordström spacetime, it is shown that the action of these gauge transformations on the abo (more) ve tensorial expressions is the same as the action of the coordinate transformations on the equivalent pseudotensorial expressions, meaning that these tensors can be set to zero at a point by a suitable choice of gauge transformation.

Pinto Neto, N.; Trajtenberg, P. I.

2000-03-01

286

Canonical quantization and cosmological particle production in non-Abelian gauge theories  

International Nuclear Information System (INIS)

A canonical quantization scheme for nonabelian gauge fields in an external, classical gravitational field is formulated and applied to the problem of cosmological Higgs and gauge boson production. Via interaction, the mass of the Higgs field not only leads to additional Higgs production, but also enables the production of massless bosons.

1987-01-01

287

Some Friedmann cosmological solutions in the scale covariant theory of gravitation  

Directory of Open Access Journals (Sweden)

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.

Aroonkumar Beesham

1991-01-01

288

Utilitarian Supersymmetric Gauge Model of Particle Interactions  

CERN Document Server

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.

Ma, Ernest

2010-01-01

289

Strain gauge installation tool  

Energy Technology Data Exchange (ETDEWEB)

A tool and a method for attaching a strain gauge to a test specimen by maaining alignment of, and applying pressure to, the strain gauge during the bonding of the gauge to the specimen. The tool comprises rigid and compliant pads attached to a spring-loaded clamp. The pads are shaped to conform to the specimen surface to which the gauge is to be bonded. The shape of the pads permits the tool to align itself to the specimen and to maintain alignment of the gauge to the specimen during the bond curing process. A simplified method of attaching a strain gauge is provided by use of the tool.

Conard, Lisa Marie (Swissvale, PA)

1998-01-01

290

On gauge fixing  

CERN Multimedia

Gauge fixing is a useful tool to simplify calculations. It is also valuable to combine different methods, in particular lattice and continuum methods. However, beyond perturbation theory the Gribov-Singer ambiguity requires further gauge conditions for a well-defined gauge-fixing prescription. Different additional conditions can, in principle, lead to different results for gauge-dependent correlation functions, as will be discussed for the example of Landau gauge. Also the relation of lattice and continuum gauge fixing beyond perturbation theory will be briefly outlined.

Maas, Axel

2010-01-01

291

Lectures on the gauge/string duality with emphasis on spectroscopy  

International Nuclear Information System (INIS)

I review recent progress on the connection between string theory and quantum chromo-dynamics in the context of the gauge/string duality. Emphasis is placed on conciseness and conceptual aspects rather than on technical details. Topics covered include the large-Nc limit of gauge theories, the gravitational description of gauge theory thermodynamics and hydrodynamics, and the physics of quarks and mesons in the quark-gluon plasma.

2010-11-12

292

Gauge Mediation in Supergravity and Gravitino Dark Matter.  

Science.gov (United States)

Gravitinos and hidden sector fields often cause a cosmological disaster in supersymmetric models. We find that a model with gravitational gauge mediation solves such a problem quite naturally. The (mu)-problem is also absent in the model. Moreover, the ab...

M. Ibe R. Kitano

2006-01-01

293

Anomaly extraction from the path integral  

International Nuclear Information System (INIS)

Fujikawa's recently proposed derivation of the anomaly from the path integral is examined. It is attempted to give a better understanding of his work. In particular, evasions of his result are discussed; for example it is shown how chiral U(1) axial invariance can be maintained by employing a gauge variant regularization prescription. A brief connection with the point-splitting method is also made. (author)

1982-01-01

294

Topological investigations of quantized gauge theories  

International Nuclear Information System (INIS)

[en] A relativistic quantum field theory provides a dynamical framework for explaining a vast variety of physical phemonena: not only are all properties of bound and scattering states contained in the theory, but also processes in which particle number changes are described. Here the author gives exact results about quantum field theory which have emerged from topological analysis. They are of three kinds. First, the fact that there may exist parameters characterizing a quantum theory which are not apparent in the Lagrangian. Second, the fact that some parameters of a Lagrangian (coupling constants, masses, etc.) cannot be arbitrary in a consistent quantum theory. Finally, third, the fact that the interaction of gauge fields with fermions is strongly constrained. The author begins these lectures by discussing gauge theories, their classical symmetries, the problem of quantization, and anomalies before coming to the main subject. He discusses Abelian and non-Abelian vector gauge theories. (Auth.)

1983-08-04

295

Chiral anomalies and differential geometry  

Energy Technology Data Exchange (ETDEWEB)

Some properties of chiral anomalies are described from a geometric point of view. Topics include chiral anomalies and differential forms, transformation properties of the anomalies, identification and use of the anomalies, and normalization of the anomalies. 22 references. (WHK)

Zumino, B.

1983-10-01

296

Enhancing orbit restitution with non-gravitational acceleration measurements for gravitation experiments  

Science.gov (United States)

A large number of tests of gravitation have now been performed in the Solar System, in particular using the motion of planets and interplanetary spacecrafts. They put severe constraints on possible deviations from General Relativity. However, at astrophysical and cosmological scales, observations show anomalies in the rotation curves of galaxies and in the relation between redshifts and luminosities of supernovae. As long as these dark components are observed by gravitational means solely, the anomalies can also be ascribed to modifications of standard gravitation. Obviously, any modification of this kind also has to pass the gravitation tests in the Solar System. Considering that theoretical models also predict deviations from General Relativity, it has become essential to map gravitation in the Solar System with high precision. This can be done by using the trajectory of interplanetary probes. To reach sufficiently precise measurements, it is necessary to correct for the non-gravitational acceleration of the spacecraft. We develop an instrument capable of measuring the non-gravitational acceleration with a precision of 1 pm.s^{-2} for an integration time of three hours. However, because of the constraints in term of mass on interplanetary missions, no drag-free system is envisioned. It is therefore necessary to introduce the non-gravitational acceleration measurements a-posteriori in the orbit restitution process. Currently, non-gravitational accelerations, such as the radiation pressure or the anisotropic thermal radiation, are taken into account by models whose parameters must be fitted. The direct measurement of these quantities enhances orbit restitution for several reasons. First, it removes parameters to be fitted in the process. Second, it measures the temporal fluctuations which cannot be taken into account by models. Third, it removes the correlations which appear in the orbit determination process between the non-gravitational acceleration and the gravitational acceleration, when the former are not measured. Keeping in mind that the Roadmap for Fundamental Physics in Space issued by ESA in 2010 recommends spacecraft tracking at the 10 pm.s^{-2} level, an emphasis will be put on the expected level of detection one can expect as far as deviation from General Relativity is concerned.

Lenoir, Benjamin; Metris, Gilles; Christophe, Bruno; Lamine, Brahim; Reynaud, Serge

2012-07-01

297

Gravitation and cosmology  

International Nuclear Information System (INIS)

The first six chapters of this book: physical fundamentals, Riemann's geometry, gravitational theory, experimental tests of the general theory of relativity, cosmology and gravitational waves, give a survey on the 'classical' results of the relativity theory. In the chapters to follow, aspects of more recent development are dealt with: new differential geometrical methods, star formation and gravitational collapse, fields in the Riemann's space, gravitation and field theory. (BJ/LH)

1975-01-01

298

Electromagnetism and gravitation  

CERN Document Server

Hypothesis: The electromagnetic field is the source of gravitation. This treatment of gravitation is consistent with the quantum theory of matter, which holds that electric charge (or `generalized charge') is the most fundamental attribute of matter. Experimental predictions of the theory include: (1) any massive body generates a time-dependent gravitational field; (2) there is a linear correlation between the gravitational red-shift of a stellar source and the energy of cosmic rays emitted by that source, given by {\\Delta \

Dalton, K

1995-01-01

299

Soliton solutions in relativistic field theories and gravitation  

CERN Multimedia

We report on some recent results on a class of relativistic lagrangian field theories supporting non-topological soliton solutions and their applications in the contexts of Gravitation and Cosmology. We analyze one and many-components scalar fields and gauge fields.

Diaz-Alonso, Joaquin

2007-01-01

300

Axial anomalies in external tensor fields  

International Nuclear Information System (INIS)

[en] The calculation of the anomaly of the axial current of Dirac fermions in external antisymmetric tensor fields of odd rank is considered. A sequence of one-dimensional supersymmetric models is presented and it is shown that their supercharges are, after quantization, Dirac operators in the external tensor fields, while their Witten partition function is the anomaly of the axial current. It is shown that the action in the corresponding functional integral for the partition function is different from the classical action. The semiclassical approximation gives the anomaly only in the case of an external tensor field of third rank with zero exterior derivative, and it is calculated in this case for arbitrary dimension. The interpretation of this field as an external gravitational field with torsion and the connection with the results of Witten and Alvarez-Gaume and the Atiyah-Singer theorem are discussed

1987-01-01

 
 
 
 
301

Detection of gravitational radiation  

International Nuclear Information System (INIS)

In this report the main contributions presented at the named symposium are collected. These concern astrophysical sources of gravitational radiation, ultracryogenic gravitational wave experiments, read out and data analysis of gravitational wave antennas, cryogenic aspects of large mass cooling to mK temperatures, and metallurgical and engineering aspects of large Cu structure manufacturing. (HSI).

1994-05-24

302

Relativity theory and gravitation  

Energy Technology Data Exchange (ETDEWEB)

The paper on relativity theory and gravitation is presented as a preface to the first of the articles submitted to the Journal on general relativity. Newtonian gravitation and and observation, relativity, and the sources of the gravitational field, are all discussed.

Bondi, H.

1986-01-01

303

Resource Letter: Gravitational Lensing  

CERN Document Server

This Resource Letter provides a guide to a selection of the literature on gravitational lensing and its applications. Journal articles, books, popular articles, and websites are cited for the following topics: foundations of gravitational lensing, foundations of cosmology, history of gravitational lensing, strong lensing, weak lensing, and microlensing.

Treu, T; Clowe, D

2012-01-01

304

Z'-gauge Bosons as Harbingers of Low Mass Strings  

CERN Document Server

Massive Z'-gauge bosons act as excellent harbingers for string compactifications with a low string scale. In D-brane models they are associated to U(1) gauge symmetries that are either anomalous in four dimensions or exhibit a hidden higher dimensional anomaly. We discuss the possible signals of massive Z'-gauge bosons at hadron collider machines (Tevatron, LHC) in a minimal D-brane model consisting out of four stacks of D-branes. In this construction, there are two massive gauge bosons, which can be naturally associated with baryon number B and B-L (L being lepton number). Here baryon number is always anomalous in four dimensions, whereas the presence of a four-dimensional B-L anomaly depends on the U(1)-charges of the right handed neutrinos. In case B-L is anomaly free, a mass hierarchy between the two associated Z'-gauge bosons can be explained. In our phenomenological discussion about the possible discovery of massive Z'-gauge bosons, we take as a benchmark scenario the dijet plus W signal, recently obser...

Anchordoqui, Luis A; Goldberg, Haim; Huang, Xing; Lüst, Dieter; Taylor, Tomasz R

2012-01-01

305

Bourdon Tube Gauge  

Science.gov (United States)

A Bourdon tube gauge animation. The objective is to describe how a Bourdon Tube Gauge measures vacuum. This simulation is from Module 101 of the vacuum technology and gas control cluster of the MATEC Module Library (MML).

2011-07-14

306

The question of anomalies in the Chern-Simons theory coupled to matter fields  

CERN Multimedia

We study the Chern-Simons theory coupled to matter field by means of an effective Lagrangian obtained from the Batalin-Fradkin-Vilkovisky formalism. We show that there is no rotational anomaly for any proper gauge we choose.

Amorim, R

1994-01-01

307

Quantum mechanics of the gravitational field in asymptotically flat space  

International Nuclear Information System (INIS)

An expression for the propagation amplitude between two gravitational field configurations in asymptotically flat space is given. It depends on two three-geometries and on an element of the Poincare group which specifies the relative location of two hyperplanes in the Minkowski space at infinity. The amplitude is obtained by path integrating over gravitational fields in the proper-time gauge which was previously used by the author for compact spaces. The causality condition, which is imposed by admitting in the path integral only positive proper-time separations between the initial and final surfaces, implies that the amplitude is not annihilated by the generator of normal deformations. It is argued that, as a consequence, it is not permissible to regard quantized gravitation theory in asymptotically flat space as an ''ordinary gauge theory'' even if one is only interested in asymptotic pro- p cesses

1983-07-15

308

The stochastic gravitational-wave background produced by non-linear cosmological perturbations  

CERN Document Server

The cosmological stochastic gravitational-wave background produced by the mildly non-linear evolution of density fluctuations is analyzed, in the frame of an Einstein-de Sitter model, by means of a fully relativistic perturbation expansion up to second order. The form of these gravitational-instability-induced gravitational waves is gauge-dependent. In the synchronous gauge, where the second-order expansion is most easily carried out, the transverse and traceless tensor modes which are produced also contain a Newtonian and post-Newtonian piece, whose interpretation as gravitational waves is non-trivial. A more direct physical understanding of this background is obtained in the so-called Poisson gauge, where it is seen to consist of a constant term plus an oscillating piece whose amplitude decays inside the Hubble radius.

Matarrese, S; Matarrese, Sabino; Mollerach, Silvia

1997-01-01

309

High pressure gauge carrier  

Energy Technology Data Exchange (ETDEWEB)

A gauge carrier for disposition in a well bore is described comprising: an inner pressure-tight housing having a chamber therein adapted to receive at least one gauge; an outer housing including support means for the inner housing therein; and a compressible liquid substantially filling any space in the chamber unfilled by the gauge.

Burris, W.J. II; Zeller, V.P.; Christensen, J.B.; Shoffner, W.H.

1988-04-05

310

Experiments on gravitation  

Energy Technology Data Exchange (ETDEWEB)

The theoretical setting of the experimental study of gravitation is indicated and a brief account is given of experiments on gravitation from Newton onwards. The main content of the review comprises surveys of three groups of experiment: the investigation of the inverse square law, studies of the weak equivalence principle and determinations of the constant of gravitation. Attention is called to the reasons for the difficulties of carrying out experiments on gravitation. In summary, it is concluded that there is no evidence for deviations from general relativity and that gravitation is mainly a manifestation of the geometry of spacetime.

Cook, A.

1988-05-01

311

Gauge fixing and residual symmetries in gauge/gravity theories with extra dimensions  

International Nuclear Information System (INIS)

[en] We study compactified pure gauge/gravitational theories with gauge-fixing terms and show that these theories possess quantum mechanical supersymmetriclike symmetries between unphysical degrees of freedom. These residual symmetries are global symmetries and generated by quantum mechanical N=2 supercharges. Also, we establish a new one-parameter family of gauge choices for higher-dimensional gravity and calculate as a check of its validity one graviton exchange amplitude in the lowest tree-level approximation. We confirm that the result is indeed ? independent and the cancellation of the ? dependence is ensured by the residual symmetries. We also give a simple interpretation of the van Dam-Veltman-Zakharov discontinuity, which arises in the lowest tree-level approximation, from the supersymmetric point of view.

2008-03-15

312

A Gravitational Effective Action on a Finite Triangulation  

CERN Document Server

We construct a function of the edge-lengths of a triangulated surface whose variation under a rescaling of all the edges that meet at a vertex is the defect angle at that vertex. We interpret this function as a gravitational effective action on the triangulation, and the variation as a trace anomaly.

Ko, A; Ko, Albert; Rocek, Martin

2006-01-01

313

Kinetically-Enhanced Anomaly Mediation  

CERN Document Server

We investigate a modification of anomaly-mediated supersymmetry breaking (AMSB) with an exotic U(1)_x gauge sector that can solve the tachyonic slepton problem of minimal AMSB scenarios. The new U(1)_x multiplet is assumed to couple directly to the source of supersymmetry breaking, but only indirectly to the minimal supersymmetric Standard Model (MSSM) through kinetic mixing with hypercharge. If the MSSM sector is also sequestered from the source of supersymmetry breaking, the contributions to the MSSM soft terms come from both AMSB and the U(1)_x kinetic coupling. We find that this arrangement can give rise to a flavour-universal, phenomenologically viable, and distinctive spectrum of MSSM superpartners. We also investigate the prospects for discovery and the most likely signatures of this scenario at the Large Hadron Collider (LHC).

Kumar, Abhishek; Spray, Andrew

2011-01-01

314

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)

1980-01-01

315

Kohn anomalies in superconductors  

International Nuclear Information System (INIS)

[en] The detailed behavior of phonon dispersion curves near momenta which span the electronic Fermi sea in a superconductor is presented. An anomaly, similar to the metallic Kohn anomaly, exists in a superconductor's dispersion curves when the frequency of the photon spanning the Fermi sea exceeds twice the superconducting energy gap. This anomaly occurs at approximately the same momentum but is stronger than the normal-state Kohn anomaly. It also survives at finite temperature, unlike the metallic anomaly. Determination of Fermi-surface diameters from the location of these anomalies, therefore, may be more successful in the superconducting phase than in the normal state. However, the superconductor's anomaly fades rapidly with increased phonon frequency and becomes unobservable when the phonon frequency greatly exceeds the gap. This constraint makes these anomalies useful only in high-temperature superconductors such as La1.85Sr0.15CuO4

1994-07-01

316

Kohn anomalies in superconductors  

Energy Technology Data Exchange (ETDEWEB)

The detailed behavior of phonon dispersion curves near momenta which span the electronic Fermi sea in a superconductor is presented. An anomaly, similar to the metallic Kohn anomaly, exists in a superconductor's dispersion curves when the frequency of the photon spanning the Fermi sea exceeds twice the superconducting energy gap. This anomaly occurs at approximately the same momentum but is [ital stronger] than the normal-state Kohn anomaly. It also survives at finite temperature, unlike the metallic anomaly. Determination of Fermi-surface diameters from the location of these anomalies, therefore, may be more successful in the superconducting phase than in the normal state. However, the superconductor's anomaly fades rapidly with increased phonon frequency and becomes unobservable when the phonon frequency greatly exceeds the gap. This constraint makes these anomalies useful only in high-temperature superconductors such as La[sub 1.85]Sr[sub 0.15]CuO[sub 4].

Flatte, M.E. (Institute for Theoretical Physics, University of Caifornia, Santa Barbara, California 93106-4030 (United States))

1994-07-01

317

Cosmic acceleration from second order gauge gravity  

CERN Document Server

We construct an infrared effective theory of gravitation based on a second order gauge formulation for the Lorentz group. The model presents a long-range modification for the gravitational field leading to a a cosmological model provided with an accelerated expansion at recent times. We fit the model parameters -- such as the coupling constant of Lagrangian's effective sector -- using super-novae type Ia and X-ray galaxy clusters data. There is good agreement between our estimative for the age of the universe and the one predicted by the standard model. The transition from the decelerated expansion regime to the accelerated one occurs recently enough to indicate a solution of the cosmic coincidence problem.

Cuzinatto, R R; Medeiros, L G; Pompeia, P J

2007-01-01

318

Classical and quantum signatures of linear gravitation  

International Nuclear Information System (INIS)

In this paper we study a domain of spacetime in which gravitational field is nearly flat. Thus a coordinate system exists for which g?? ??? + h??, |h??| ??| transforms as a tensor with respect to the Lorentz group, and as it is the case of electrodynamics, there is a gauge group. We propose a generalisation of linear gravitoelectromagnetics and the main results can be summarized as follows. 1. Maxwell-type gravitational equations can be written as the single-graviton quantum equation. However, some fundamental electrodynamical and gravitational phenomena are standing beyond the frames of a Maxwell-type theory, that is in non-abelian Yang-Mills regions. 2. A new derivation of the Unruh effect formula on the basis of Einstein's principle of equivalence. 3. Absorption of linearized gravitational waves may be caused by an 'Ohm's gravitational law'. 4. We establish a stronger limit for the longitudinal graviton mass (mgl ? 2 x 10-66 g). 5. Energy density of the vacuum is half that of the energy density of cosmic matter. This result agrees with the relation between the density of the vacuum energy and the energy of cosmic matter that has been proposed in order to solve the old problem of cosmological models involving dark matter and critical total energy density. 6. The interaction of a gravitational wave with a free or bounded particle can be studied in a Hamilton-Weber quantum mechanical framework. 7. The possibility of force-free gravitomagnetic fields and reconnection of field lines. 8. Spontaneous generation of gravitomagnetic field in an imploding matter. (authors)

2000-01-01

319

Farri theorem for non-abelian gauge lagrangians  

International Nuclear Information System (INIS)

[en] It is shown that in gauge-invariant Lagrangian (without ?5-anomalies), based on irreducible representation of the simple compact Lie algebra, the C-parity can be always defined. The Lagrangian is invariant with respect to this C-parity. It imposes definite requirements to the algebraic structure of the vertex functions

1981-01-01

320

Gravitational Chern-Simons Lagrangian terms and spherically symmetric spacetimes  

CERN Document Server

We show that for general spherically symmetric configurations, contributions of general gravitational and mixed gauge-gravitational Chern-Simons terms to the equations of motion vanish identically in $D>3$ dimensions. This implies that such terms in the action do not affect Birkhoff's theorem or any previously known spherically symmetric solutions. Furthermore, we investigate the thermodynamical properties using the procedure described in an accompanying paper. We find that in $D>3$ static spherically symmetric case Chern-Simons terms do not contribute to the entropy either. Moreover, if one requires only for the metric tensor to be spherically symmetric, letting other fields unrestricted, the results extend almost completely, with only one possible exception --- Chern-Simons Lagrangian terms in which the gravitational part is just the $n=2$ irreducible gravitational Chern-Simons term.

Bonora, Loriano; Prester, Predrag Dominis; Pallua, Silvio; Smoli?, Ivica

2011-01-01

 
 
 
 
321

On Certain Conceptual Anomalies in Einstein's Theory of Relativity  

Directory of Open Access Journals (Sweden)

Full Text Available There are a number of conceptual anomalies occurring in the Standard exposition of Einstein's Theory of Relativity. These anomalies relate to issues in both mathematics and in physics and penetrate to the very heart of Einstein's theory. This paper reveals and amplifies a few such anomalies, including the fact that Einstein's field equations for the so-called static vacuum configuration, $R_{mu u} = 0$, violates his Principle of Equivalence, and is therefore erroneous. This has a direct bearing on the usual concept of conservation of energy for the gravitational field and the conventional formulation for localisation of energy using Einstein's pseudo-tensor. Misconceptions as to the relationship between Minkowski spacetime and Special Relativity are also discussed, along with their relationships to the pseudo-Riemannian metric manifold of Einstein's gravitational field, and their fundamental geometric structures pertaining to spherical symmetry.

Crothers S. J.

2008-01-01

322

Gauged supergravities from Bianchi's group manifolds  

International Nuclear Information System (INIS)

[en] We construct maximal D = 8 gauged supergravities by the reduction of D 11 supergravity over three-dimensional group manifolds. Such manifolds are classified into two classes, A and B, and eleven types. This Bianchi classification carries over to the gauged supergravities. The class A theories have 1/2 BPS domain wall solutions that uplift to purely gravitational solutions consisting of 7D Minkowski and a 4D Euclidean geometry. These geometries are generically singular. The two regular exceptions correspond to the near-horizon limit of the single- or double-centre Kaluza-Klein monopole. In contrast, the class B supergravities are defined by a set of equations of motion that cannot be integrated to an action and allow for no 1/2 BPS domain walls

2004-05-21

323

Imaging of vascular anomalies.  

UK PubMed Central (United Kingdom)

Accurate characterization of vascular anomalies is important in predicting clinical course and guiding treatment. This article provides an imaging review of vascular anomalies, highlighting the particular imaging characteristics of hemangiomas and malformations. Discussed are the appropriate imaging modalities for the evaluation of the anomalies and the associated abnormalities that require further investigation.

Jarrett DY; Ali M; Chaudry G

2013-04-01

324

Tracheobronchial Branching Anomalies  

Energy Technology Data Exchange (ETDEWEB)

There are various congenital anomalies with respect to the number, length, diameter, and location of tracheobronchial branching patterns. The tracheobronchial anomalies are classified into two groups. The first one, anomalies of division, includes tracheal bronchus, cardiac bronchus, tracheal diverticulum, pulmonary isomerism, and minor variations. The second one, dysmorphic lung, includes lung agenesis-hypoplasia complex and lobar agenesis-aplasia complex

Hong, Min Ji; Kim, Young Tong; Jou, Sung Shick [Soonchunhyang University, Cheonan Hospital, Cheonan (Korea, Republic of); Park, A Young [Soonchunhyang University College of Medicine, Asan (Korea, Republic of)

2010-04-15

325

Gravitational Space Dilation  

CERN Multimedia

We point out that, if one accepts the view that the standard second on an atomic clock is dilated at low gravitational potential (ordinary gravitational time dilation), then the standard meter must also be dilated at low gravitational potential and by the same factor (gravitational space dilation). These effects may be viewed as distortions of the time and length standards by the gravitational field, and measurements made with these distorted standards can be "corrected" by means of a conformal transformation applied to the usual spacetime metric of general relativity. The surprising feature of this single-observer picture is a substantial simplification of interpretation and formalism for numerous phenomena in a static gravitational field as compared to the conventional "many-observer" interpretation of general relativity.

Cook, Richard J

2009-01-01

326

Nonplanar anomalies in noncommutative theories and the Green-Schwarz mechanism  

International Nuclear Information System (INIS)

We discuss nonplanar anomalies in noncommutative gauge theories. In particular we show that a nonplanar anomaly exists when the external noncommutative momentum is zero and that it leads to a non-conservation of the associated axial charge. In the case of nonplanar local anomalies, a cancellation of the anomaly can be achieved by a Green-Schwarz mechanism. In an example of D3 branes placed on an orbifold singularity that leads to a chiral theory, the mechanism involves twisted RR fields which propagate with zero noncommutative momentum. Global anomalies are not cancelled and, in particular, the decay ?0?2? is allowed. (author)

2002-01-01

327

Jacobi identity anomaly in closed string field theory  

Energy Technology Data Exchange (ETDEWEB)

The Jacobi identity, which is an indispensable property for gauge invariant closed string field theory, is apparently broken in cases where one of the four legs of the identity has vanishing string-length. This phenomenon contradicts the general proof of the identity valid at the critical dimension. We examine the general proof and clarify the mechanism of this Jacobi identity anomaly. (author).

Hata, Hiroyuki (Kyoto Univ. (Japan). Dept. of Physics)

1991-11-01

328

Dimensional regularization and ?5. The spurious anomalies problem  

International Nuclear Information System (INIS)

A change of principles of operation with external diagram pulses ia proposed in dimensional regularization with four-dimensional ?5-matrix. It is shown that in this case for Abelian gauge theories in one-loop approximation false axial anomalies do not appear. 10 refs.

1989-01-01

329

A Lorentz gauge theory as a model of emergent gravity  

CERN Multimedia

We consider a class of Lorentz gauge gravity theories within Riemann-Cartan geometry which admits a topological phase in gravitational sector. The dynamic content of such theories is determined only by contortion part of the Lorentz gauge connection. We demonstrate that there is a unique Lagrangian which admits propagating vector spin one mode in correspondence with gauge theories of other fundamental interactions. Remarkably, despite of R^2 type of the Lagrangian and non-compact structure of the Lorentz gauge group, the model possesses rather a positive definite Hamiltonian. This has been proved in the lowest order of perturbation theory. This implies further consistent quantization and leads to renormalizable quantum theory. It is assumed that proposed model describes possible mechanism of emergent Einstein gravity at very early stages of the Universe due to quantum dynamics of contortion.

Pak, D G; Tsukioka, Takuya

2011-01-01

330

Pulsars and Gravitational Waves  

CERN Multimedia

The relationship between pulsar-like compact stars and gravitational waves is briefly reviewed. Due to regular spins, pulsars could be useful tools for us to detect ~nano-Hz low-frequency gravitational waves by pulsar-timing array technique; besides, they would also be ~kilo-Hz high-frequency gravitational wave radiators because of their compactness. The wave strain of an isolate pulsar depends on the equation state of cold matter at supra-nuclear densities. Therefore, a real detection of gravitational wave should be very meaningful in gravity physics, micro-theory of elementary strong interaction, and astronomy.

Lee, K J; Qiao, G J

2011-01-01

331

Gauge field models  

International Nuclear Information System (INIS)

Stora's analysis is continued in discussing the nonabelian (Yang-Mills) gauge field models (G.F.M.). The gauge independence of the physical scattering operator is discussed in some details and the connection between its unitary and the Slavnov symmetry outlined. Only the models involving semisimple gauge groups are considered. This greatly simplifies the analysis of the possible quantum corrections to the Quantum Action Principle which is reduced to the study of the cohomology group of the Lie algebra characterizing the gauge theory. The discussion is at the classical level for the algebraic properties of the SU(2) Higgs-Kibble-Englert-Brout-Faddeev-Popov lagrangian and its invariance under Slavnov identity transformations is exhibited. The renormalization of the Slavnov identity in the G.M.F. involving semisimple gauge groups is studied. The unitary and gauge independence of the physical S operator in the SU(2) H.K. model is dealt with.

1975-08-17

332

Renormalization of R/sup 2/-gravitation  

Energy Technology Data Exchange (ETDEWEB)

The structure of renormalization of the R/sup 2/ gravitation in an arbitrary linear gauge renormalizable with respect to the index is found in a simple manner. Thus, we have in particular proved the validity of the ''locality hypothesis'' which concerns the general local representation for n-loop counter-terms and is a starting point for studying the renormalization structure in a traditional manner. The validity of this hypothesis is as well supported by direct solution of the Ward identities for counter-terms.

Voronov, B.L. (AN SSSR, Moscow. Fizicheskij Inst.); Tyutin, I.V. (AN SSSR, Tomsk. Inst. Sil' notochnoj Ehlektroniki)

1984-04-01

333

Eikonal methods applied to gravitational scattering amplitudes  

Science.gov (United States)

We apply factorization and eikonal methods from gauge theories to scattering amplitudes in gravity. We hypothesize that these amplitudes factor into an IR-divergent soft function and an IR-finite hard function, with the former given by the expectation value of a product of gravitational Wilson line operators. Using this approach, we show that the IR-divergent part of the n-graviton scattering amplitude is given by the exponential of the one-loop IR divergence, as originally discovered by Weinberg, with no additional subleading IR-divergent contributions in dimensional regularization.

Naculich, Stephen G.; Schnitzer, Howard J.

2011-05-01

334

High temperature pressure gauge  

Energy Technology Data Exchange (ETDEWEB)

A high temperature pressure gauge comprising a pressure gauge positioned in fluid communication with one end of a conduit which has a diaphragm mounted in its other end. The conduit is filled with a low melting metal alloy above the diaphragm for a portion of its length with a high temperature fluid being positioned in the remaining length of the conduit and in the pressure gauge.

Echtler, J. Paul (Pittsburgh, PA); Scandrol, Roy O. (Library, PA)

1981-01-01

335

An octonionic gauge theory  

Energy Technology Data Exchange (ETDEWEB)

The nonassociativity of the octonion algebra makes necessitates a bimodule representation, in which each element is represented by a left and a right multiplier. This representation can then be used to generate gauge transformations for the purpose of constructing a field theory symmetric under a gauged octonion algebra, the nonassociativity of which appears as a failure of the representation to close, and hence produces new interactions in the gauge field kinetic term of the symmetric Lagrangian. 5 refs., 1 tab.

Lassig, C.C.; Joshi, G.C.

1995-01-19

336

Adventures in Coulomb Gauge  

International Nuclear Information System (INIS)

We study the phase structure of SU(2) gauge theories at zero and high temperature, with and without scalar matter fields, in terms of the symmetric/broken realization of the remnant gauge symmetry which exists after fixing to Coulomb gauge. The symmetric realization is associated with a linearly rising color Coulomb potential (which we compute numerically), and is a necessary but not sufficient condition for confinement.

2003-09-26

337

Introduction to gauge theories  

International Nuclear Information System (INIS)

[en] 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

1984-01-01

338

An octonionic gauge theory  

International Nuclear Information System (INIS)

The nonassociativity of the octonion algebra makes necessitates a bimodule representation, in which each element is represented by a left and a right multiplier. This representation can then be used to generate gauge transformations for the purpose of constructing a field theory symmetric under a gauged octonion algebra, the nonassociativity of which appears as a failure of the representation to close, and hence produces new interactions in the gauge field kinetic term of the symmetric Lagrangian. 5 refs., 1 tab

1995-01-01

339

Optical-Gravitation Nonlinearity: A Change of Gravitational Coefficient G induced by Gravitation Field  

Directory of Open Access Journals (Sweden)

Full Text Available Nonlinear effect of the gravitation field of spherically symmetric mass on the gravitational coefficient G has been analysed. In frame of the approaches of parametric optics and gravitation nonlinearity we have shown that the gravitation field of spherically symmetric mass can lead to changes in the gravitational coefficient G.

R. Vlokh; M. Kostyrko

2006-01-01

340

Chiral U(1) anomaly in D = 4 super Yang-Mills theory coupled to supergravity  

International Nuclear Information System (INIS)

[en] We evaluate the chiral U(1) anomaly in D = 4 supersymmetric Yang-Mills theory coupled to supergravity. We consider not only the minimal coupling between the gauge fields and fermions but also the interaction term which mixes gravitino and gaugino. We show that the mixing interaction gives the new contributions to the anomaly. This fact suggests necessity for reexamination of the Green-Schwarz anomaly cancellation mechanism. (author)

1987-01-01

 
 
 
 
341

Supersymmetric gauge theories with a free algebra of invariants  

CERN Multimedia

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.

Dotti, G; Skiba, W; Dotti, Gustavo; Manohar, Aneesh V.; Skiba, Witold

1998-01-01

342

Supersymmetric gauge theories with a free algebra of invariants  

International Nuclear Information System (INIS)

[en] 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.)

1998-10-26

343

Are gauge symmetries symmetries  

International Nuclear Information System (INIS)

In topologically non-trivial gauge theories there is in general an obstruction for implementing gauge transformations on the fields, and even those which can be implemented may fail to be symmetries. For instantons no non-trivial gauge transformation can be implemented. For a monopole the residual symmetry group G is implementable if the projection onto the centre of its non-Abelian charge Q is quantized. G is however a symmetry group only if Q belongs actually to the centre. In the non-Abelian Bohm-Aharonov experiment all gauge transformations are implementable but they are symmetries only if the enclosed flux is quantized

1984-01-01

344

Lorentz-violating massive gauge and gravitational fields  

CERN Multimedia

We study nonlinear dynamics in models of Lorentz-violating massive gravity. The Boulware-Deser instability restricts severely the class of acceptable theories. We identify a model that is stable. It exhibits the following bizarre but interesting property: there are only two massive propagating degrees of freedom in the spectrum, and yet long-range instantaneous interactions are present in the theory. We discuss this property on a simpler example of a photon with a Lorentz-violating mass term where the issues of (a)causality are easier to understand. Depending on the values of the mass parameter these models can either be excluded, or become phenomenologically interesting. We discuss a similar example with more degrees of freedom, as well as a model without the long-range instantaneous interactions.

Gabadadze, Gregory T; Gabadadze, Gregory; Grisa, Luca

2005-01-01

345

Lorentz-violating massive gauge and gravitational fields  

Energy Technology Data Exchange (ETDEWEB)

We study nonlinear dynamics in models of Lorentz-violating massive gravity. The Boulware-Deser instability restricts severely the class of acceptable theories. We identify a model that is stable. It exhibits the following bizarre but interesting property: there are only two massive propagating degrees of freedom in the spectrum, and yet long-range instantaneous interactions are present in the theory. We discuss this property on a simpler example of a photon with a Lorentz-violating mass term where the issues of (a)causality are easier to understand. Depending on the values of the mass parameter these models can either be excluded, or become phenomenologically interesting. We discuss a similar example with more degrees of freedom, as well as a model without the long-range instantaneous interactions.

Gabadadze, Gregory [Center for Cosmology and Particle Physics, Department of Physics, New York University, New York, NY 10003 (United States)]. E-mail: gg32@nyu.edu; Grisa, Luca [Center for Cosmology and Particle Physics, Department of Physics, New York University, New York, NY 10003 (United States)

2005-06-23

346

Gravitational effects from earthquakes  

Science.gov (United States)

Two types of propagating gravitational effects, from the mass redistribution within the Earth due to a large earthquake, are investigated: (i) the velocity of the change of the Newtonian potential field; and (ii) the gravitational luminosity of the seismic source. The mass redistribution caused by an earthquake and the resulting change in the gravitational potential field is computed through application of geophysical dislocation theory. The global mass redistribution is postulated to be progressive, starting at the instant (and location) of the nucleation of the earthquake fault rupture, and then spreading globally at the velocities of various seismic waves. Information about the changes of the gravitational potential is postulated to travel at the velocity of light. Superconducting gravimeters (SG) can resolve changes of the order of 10 nGal, i.e., (10(-9) cm/s(2)) (1 Gal = 0.001 0197g), sufficient to detect the changes in the potential field. The time difference between observation of the change of the potential field and the arrival of the primary seismic wave from the earthquake would allow a crude estimation of the velocity of the gravitational effect. A preliminary search for the preseismic gravitational signal using an SG has given inconclusive results, primarily due to the limitations of the spline curve fitting methods. Despite this, we suggest that the observation of preseismic gravitational potential changes should be feasible, with the existing array of SGs in the Global Geodynamics Project (GGP) network, and by detectors designed to observe gravitational radiation (e.g., the Laser Interferometer Gravitational-wave Observatory (LIGO)). We have used published values of the changes in the Earth's inertia tensor due to the Alaska earthquake of 1964 to estimate the magnitude of the metric perturbation of the gravitational wave produced by such an earthquake. The gravitational luminosity is estimated at 1.90 x 10(-10)erg/s (1 erg/s = 10(-7) W D 1 J/s).

Hayes, T. J.; Valluri, S. R.; Mansinha, L.

2004-12-01

347

Gravitational effects in field gravitation theory  

International Nuclear Information System (INIS)

The possibilities to describe various gravitation effects of field gravitation theory (FGT) are considered. Past-Newtonian approximation of the FGT has been constructed and on the basis of this approximation it has been shown that the field theory allows one to describe the whole set of experimental facts. The comparison of post-Newtonian parameters in FGT with those in the Einstein's theory makes it clear that these two; theories are undistinguishable from the viewpoint of any experiments, realized with post-Newtonian accuracy. Gravitational field of an island type source with spherically symmetrical distribution of matter and unstationary homogeneous model of Universe, which allows to describe the effect of cosmological red shift, are considered

1979-01-01

348

A numerical solution to the local cohomology problem in U(1) chiral gauge theories  

Energy Technology Data Exchange (ETDEWEB)

We consider a numerical method to solve the local cohomology problem related to the gauge anomaly cancellation in U(1) chiral gauge theories. In the cohomological analysis of the chiral anomaly, it is required to carry out the differentiation and the integration of the anomaly with respect to the continuous parameter for the interpolation of the admissible gauge fields. In our numerical approach, the differentiation is evaluated explicitly through the rational approximation of the overlap Dirac operator with Zolotarev optimization. The integration is performed with a Gaussian Quadrature formula, which turns out to show rather good convergence. The Poincare lemma is reformulated for the finite lattice and is implemented numerically. We compute the current associated with the cohomologically trivial part of the chiral anomaly in two-dimensions and check its locality properties. (author)

Kadoh, Daisuke; Kikukawa, Yoshio [Department of Physics, Nagoya University, Nagoya 464-8602 (Japan)]. E-mail: kikukawa@eken.phys.nagoya-u.ac.jp

2005-01-01

349

Running Couplings in Quantum Theory of Gravity Coupled with Gauge Fields  

CERN Document Server

In this paper we study the coupled system of non-abelian gauge fields with higher-derivative gravity. Charge renormalization is investigated in this coupled system. It is found that the leading term in the gauge coupling beta function comes due to interaction of gauge fields with gravitons. This is shown to be a universal quantity in the sense that it doesn't depend on the gauge coupling and the gauge group, but may depend on the other couplings of the action (gravitational and matter). The coupled system is studied at one-loop. It is found that the leading term of gauge beta function is zero at one-loop in four dimensions. The effect of gauge fields on the running of gravitational couplings is investigated. The coupled system of gauge field with higher-derivative gravity is shown to satisfy unitarity when quantum corrections are taken in to account. Moreover, it is found that Newton constant goes to zero at short distances. In this renormalizable and unitary theory of gauge field coupled with higher-derivati...

Narain, Gaurav

2013-01-01

350

Geometric theory of gravitation  

International Nuclear Information System (INIS)

The problem of geometric gravitation theory is discussed. An important geometric object - affine connection - is lost in the Einstein gravitation theory. It is noted that the detection of the lost object allows one to make the theory quite geometric. 1 ref.

1989-01-01

351

Gravitational Separator of Isotopes  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this work we show a gravitational separator of isotopes which can be much more effective than those used in the conventional processes of isotopes separation. It is based on intensification of the gravitational acceleration, and can generate accelerations tens of times more intense than those gen...

De Aquino, Fran

352

Advanced Gravitational Wave Detectors  

Science.gov (United States)

Part I. An Introduction to Gravitational Wave Astronomy and Detectors: 1. Gravitational waves D. G. Blair, L. Ju, C. Zhao and E. J. Howell; 2. Sources of gravitational waves D. G. Blair and E. J. Howell; 3. Gravitational wave detectors D. G. Blair, L. Ju, C. Zhao, H. Miao, E. J. Howell, and P. Barriga; 4. Gravitational wave data analysis B. S. Sathyaprakash and B. F. Schutz; 5. Network analysis L. Wen and B. F. Schutz; Part II. Current Laser Interferometer Detectors: Three Case Studies: 6. The Laser Interferometer Gravitational-Wave Observatory P. Fritschel; 7. The VIRGO detector S. Braccini; 8. GEO 600 H. Lück and H. Grote; Part III. Technology for Advanced Gravitational Wave Detectors: 9. Lasers for high optical power interferometers B. Willke and M. Frede; 10. Thermal noise, suspensions and test masses L. Ju, G. Harry and B. Lee; 11. Vibration isolation: Part 1. Seismic isolation for advanced LIGO B. Lantz; Part 2. Passive isolation J-C. Dumas; 12. Interferometer sensing and control P. Barriga; 13. Stabilizing interferometers against high optical power effects C. Zhao, L. Ju, S. Gras and D. G. Blair; Part IV. Technology for Third Generation Gravitational Wave Detectors: 14. Cryogenic interferometers J. Degallaix; 15. Quantum theory of laser-interferometer GW detectors H. Miao and Y. Chen; 16. ET. A third generation observatory M. Punturo and H. Lück; Index.

Blair, D. G.; Howell, E. J.; Ju, L.; Zhao, C.

2012-02-01

353

Relativistic gravitation theory  

International Nuclear Information System (INIS)

On the basis of the special relativity and geometrization principle a relativistic gravitation theory (RGT) is unambiguously constructed with the help of a notion of a gravitational field as a physical field in Faraday-Maxwell spirit, which posesses energy momentum and spins 2 and 0. The source of gravitation field is a total conserved energy-momentum tensor for matter and for gravitation field in Minkowski space. In the RGT conservation laws for the energy momentum and angular momentum of matter and gravitational field hold rigorously. The theory explains the whole set of gravitation experiments. Here, due to the geometrization principle the Riemannian space is of a field origin since this space arises effectively as a result of the gravitation field origin since this space arises effectively as a result of the gravitation field action on the matter. The RGT astonishing prediction is that the Universe is not closed but ''flat''. It means that in the Universe there should exist a ''missing'' mass in some form of matter

1984-01-01

354

(Non-)Aligned gauges and global gauge symmetry breaking  

CERN Multimedia

The concept of (global) gauge symmetry breaking plays an important role in many areas of physics. Since the corresponding symmetry is a gauge symmetry, its breaking is actually gauge-dependent. Thus, it is possible to design gauges which restore the symmetry as good as possible. Such gauge constructions will be detailed here, illustrated with the use of lattice gauge theory. Their use will be discussed for the cases of the Higgs effect, high-baryon density color superconductors, and BRST symmetry.

Maas, Axel

2012-01-01

355

The Gravitational Spacecraft  

CERN Multimedia

There is a electromagnetic factor of correlation between gravitational mass and inertial mass, which in specific electromagnetic conditions, can be reduced, nullified, negated, and increased. This means that gravitational forces can be reduced, nullified, inverted and intensified by means of electromagnetic fields. Such control of the gravitational interaction can have a lot of practical applications. For example, a new concept of spacecraft and aerospace flight arises from the possibility of the electromagnetic control of the gravitational mass.Some theoretical consequences of the mentioned correlation are: the generalization of Newton=92s second law for the motion (New law for Inertia), the deduction of the differential equation for entropy (second law of Thermodynamics), unification of gravitational and electromagnetic interactions .

D'Aquino, F

1998-01-01

356

Gravitational diffraction radiation  

CERN Multimedia

We show that if the visible universe is a membrane embedded in a higher-dimensional space, particles in uniform motion radiate gravitational waves because of spacetime lumpiness. This phenomenon is analogous to the electromagnetic diffraction radiation of a charge moving near to a metallic grating. In the gravitational case, the role of the metallic grating is played by the inhomogeneities of the extra-dimensional space, such as a hidden brane. We derive a general formula for gravitational diffraction radiation and apply it to a higher-dimensional scenario with flat compact extra dimensions. Gravitational diffraction radiation may carry away a significant portion of the particle's initial energy. This allows to set stringent limits on the scale of brane perturbations. Physical effects of gravitational diffraction radiation are briefly discussed.

Cardoso, V; Pimenta, M; Cardoso, Vitor; Cavaglia, Marco; Pimenta, Mario

2006-01-01

357

A Gravitational Entropy Proposal  

CERN Multimedia

We propose a thermodynamically motivated measure of gravitational entropy based on the Bel-Robinson tensor, which has a natural interpretation as the effective super-energy-momentum tensor of free gravitational fields. The specific form of this measure differs depending on whether the gravitational field is Coulomb-like or wave-like, and reduces to the Bekenstein-Hawking value when integrated over the interior of a Schwarzschild black hole. For scalar perturbations of a Robertson-Walker geometry we find that the entropy goes like the Hubble weighted anisotropy of the gravitational field, and therefore increases as structure formation occurs. This is in keeping with our expectations for the behaviour of gravitational entropy in cosmology, and provides a thermodynamically motivated arrow of time for cosmological solutions of Einstein's field equations. It is also in keeping with Penrose's Weyl curvature hypothesis.

Clifton, Timothy; Tavakol, Reza

2013-01-01

358

A gravitational entropy proposal  

Science.gov (United States)

We propose a thermodynamically motivated measure of gravitational entropy based on the Bel-Robinson tensor, which has a natural interpretation as the effective super-energy-momentum tensor of free gravitational fields. The specific form of this measure differs depending on whether the gravitational field is Coulomb-like or wave-like, and reduces to the Bekenstein-Hawking value when integrated over the interior of a Schwarzschild black hole. For scalar perturbations of a Robertson-Walker geometry we find that the entropy goes like the Hubble weighted anisotropy of the gravitational field, and therefore increases as structure formation occurs. This is in keeping with our expectations for the behaviour of gravitational entropy in cosmology, and provides a thermodynamically motivated arrow of time for cosmological solutions of Einstein’s field equations. It is also in keeping with Penrose’s Weyl curvature hypothesis.

Clifton, Timothy; Ellis, George F. R.; Tavakol, Reza

2013-06-01

359

Gravitational corrections to the scattering of charged pions  

CERN Document Server

In this letter we discuss the role of gravitational contributions to the running of the electric charge through the evaluation of the scattering amplitude of charged pions in scalar electrodynamics. Computing the quadratic divergent part of the S-matrix amplitude for two distinct scattering processes, we show that a single definition of the running of the electric charge, that render it asymptotically free, can be made for both processes. Our result agrees with earlier ones, based on the calculation of the effective action, which suggest that the running of gauge coupling constants are driven in the direction of asymptotic freedom, when quantum gravitational corrections are taken into account.

Charneski, B; da Silva, A J

2013-01-01

360

Ghost properties of algebraically extended theories of gravitation  

International Nuclear Information System (INIS)

Recently a technique for extending general relativity called algebraic extension was shown to yield only five classes of gravitational theories (general relativity plus four extensions). The particle spectra of these theories are analysed and it is shown that only one of these extensions is ghost free. Two inequivalent theories are shown to result from this extension at the linearised level. One of these is the linearised version of Moffat's theory of gravitation; the other is a new theory which possesses an additional gauge invariance which has been associated with a closed string. (author).

1986-01-01

 
 
 
 
361

Ghost-free, nonlinear, spin-two, conformal gauge theory  

Energy Technology Data Exchange (ETDEWEB)

Conformal gravity is examined with the aim of constructing a renormalizable quantum field theory of gravitation. Acting on suggestions of ghost-free, linear conformal gravity, we examine conformal gauge theory. The correct choice of constraints is determined by comparison with the ghost-eliminating constraints of the linear theory. (These are quite different from those introduced previously in conformal gauge theories.) Einstein's field equation appears as the integrability condition for the constraint. Minimal coupling to massless matter preserves local, conformal symmetry.

Fronsdal, C.

1984-11-15

362

Gauge theory of dislocations  

International Nuclear Information System (INIS)

In this continuation of work by the author the notion of the distortion of an ideal crystal structure is generalized and the gauge field is defined, fundamental states (vacuum configurations) of which are the crystal structure elementary distortions due to dislocations. The form of the structure equations of the connection form defined by this gauge field is discussed.

1987-01-01

363

Gauge theory of dislocations  

Energy Technology Data Exchange (ETDEWEB)

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.

Trzesowski, A.

1987-11-01

364

Gauge invariance and constraints  

International Nuclear Information System (INIS)

For a wide class of gauge invariant systems with open gauge algebras the Hamiltonian description is constructed and the Poisson brackets of the constraints are calculated. It is shown that in the case under consideration there arise only first class constraints. 9 refs

1991-01-01

365

Hot Conformal Gauge Theories  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We compute the nonzero temperature free energy up to the order g^6 \\ln(1/g) in the coupling constant for vector like SU(N) gauge theories featuring matter transforming according to different representations of the underlying gauge group. The number of matter fields, i.e. flavors, is arranged in such...

Mojaza, Matin; Pica, Claudio; Sannino, Francesco

366

Ionization vacuum gauge  

International Nuclear Information System (INIS)

The gauge includes, such like Bayard-Alpert gauge, in an envelope at very low pressure a cathode, a grid for collecting the electrons surrounding the ion collector. The cathode is a cold cathode with microsources of electrons on its surface which is orientated towards the ion collector.

1991-07-23

367

Exact Space-Time Gauge Symmetry of Gravity, Its Couplings and Approximate Internal Symmetries in a Total-Unified Model  

CERN Multimedia

Gravitational field is the manifestation of space-time translational ($T_4$) gauge symmetry, which enables gravitational interaction to be unified with the strong and the electroweak interactions. Such a total-unified model is based on a generalized Yang-Mills framework in flat space-time. Following the idea of Glashow-Salam-Ward-Weinberg, we gauge the groups $T_4 \\times (SU_3)_{color} \\times SU_2 \\times U_1\\times U_{1b}$ on equal-footing, so that we have the total-unified gauge covariant derivative ${\\bf \\d}_{\\mu} = \\p_{\\mu} - ig\\phi_{\\mu}^{\

Hsu, Jong-Ping

2013-01-01

368

The heterotic ?-model with background gauge fields  

International Nuclear Information System (INIS)

[en] We develop methods for simplifying considerably the computation of ?-functions for the heterotic ?-model in the presence of background gauge fields. These methods are used to obtain three-loop results. Up to the overall normalization of the O(?'2) contribution, the ?-functions are on-shell equivalent to the equations of motion derived from an effective action which has been obtained previously in the string S-matrix approach. Our results shed, however, new light on the off-shell relation between these field equations and the ?-functions. It is also shown that, to all orders in ?', the net effect of gauge anomalies is the addition of a Chern-Simons term to the torsion. (orig.)

1989-02-20

369

Conservation of Gravitational Energy Momentum and Renormalizable Quantum Theory of Gravitation  

Directory of Open Access Journals (Sweden)

Full Text Available Viewing gravitational energy-momentum  as equal by observation, but different in essence from inertial energymomentum  naturally leads to the gauge theory of volume-preserving diffeomorphisms of an inner Minkowski space  which can describe gravitation at the classical level. This theory is quantized in the path integral formalism starting with a non-covariant Hamiltonian formulation with unconstrained canonical field variables and a manifestly positive Hamiltonian. The relevant path integral measure and weight are then brought into a Lorentz- and gauge-covariant form allowing to express correlation functions—applying the De Witt-Faddeev-Popov approach—in any meaningful gauge. Next the Feynman rules are developed and the quantum effective action at one loop in a background field approach is renormalized which results in an asymptotically free theory without presence of other fields and in a theory without asymptotic freedom including the Standard Model (SM) fields. Finally the BRST apparatus is developed as preparation for the renormalizability proof to all orders and a sketch of this proof is given.

Christian Wiesendanger

2013-01-01

370

Discrete Noncommutative Gauge Theory  

CERN Multimedia

A review of the relationships between matrix models and noncommutative gauge theory is presented. A lattice version of noncommutative Yang-Mills theory is constructed and used to examine some generic properties of noncommutative quantum field theory, such as UV/IR mixing and the appearence of gauge-invariant open Wilson line operators. Morita equivalence in this class of models is derived and used to establish the generic relation between noncommutative gauge theory and twisted reduced models. Finite dimensional representations of the quotient conditions for toroidal compactification of matrix models are thereby exhibited. The coupling of noncommutative gauge fields to fundamental matter fields is considered and a large mass expansion is used to study properties of gauge-invariant observables. Morita equivalence with fundamental matter is also presented and used to prove the equivalence between the planar loop renormalizations in commutative and noncommutative quantum chromodynamics.

Szabó, R J

2001-01-01

371

Embedding variables in the canonical theory of gravitating shells  

Energy Technology Data Exchange (ETDEWEB)

A thin shell of light-like dust with its own gravitational field is studied in the special case of spherical symmetry. The action functional for this system due to Louko, Whiting, and Friedman is reduced to Kuchar form: the new variables are embeddings, their conjugate momenta, and Dirac observables. The concepts of background manifold and covariant gauge fixing, that underlie these variables, are reformulated in a way that implies the uniqueness and gauge invariance of the background manifold. The reduced dynamics describes motion on this background manifold.

Hajicek, Petr E-mail: hajicek@itp.unibe.ch; Kiefer, Claus

2001-06-11

372

Embedding variables in the canonical theory of gravitating shells  

CERN Multimedia

A thin shell of lightlike dust with its own gravitational field is studied in the special case of spherical symmetry. The action functional for this system due to Louko, Whiting, and Friedman is reduced to Kucha\\v{r} form: the new variables are embeddings, their conjugate momenta, and Dirac observables. The concepts of background manifold and covariant gauge fixing, that underlie these variables, are reformulated in a way that implies the uniqueness and gauge invariance of the background manifold. The reduced dynamics describes motion on this background manifold.

Hajicek, P

2001-01-01

373

Real Representation in Chiral Gauge Theories on the Lattice  

International Nuclear Information System (INIS)

The Weyl fermion belonging to the real representation of the gauge group provides a simple illustrative example for Luescher's gauge-invariant lattice formulation of chiral gauge theories. We can explicitly construct the fermion integration measure globally over the gauge-field configuration space in the arbitrary topological sector; there is no global obstruction corresponding to the Witten anomaly. It is shown that this Weyl formulation is equivalent to a lattice formulation based on the Majorana (left-right-symmetric) fermion, in which the fermion partition function is given by the Pfaffian with a definite sign, up to physically irrelevant contact terms. This observation suggests a natural relative normalization of the fermion measure in different topological sectors for the Weyl fermion belonging to the complex representation. (author)

2000-01-01

374

Anomaly induced effects in a magnetic field  

International Nuclear Information System (INIS)

[en] 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 and A, etc

2008-04-11

375

Conformal Anomalies in Hydrodynamics  

CERN Multimedia

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.

Eling, Christopher; Theisen, Stefan; Yankielowicz, Shimon

2013-01-01

376

Gauge models with hidden topology  

International Nuclear Information System (INIS)

Gauge models in which vacuum possesses nontrivial topological characteristics are described by analogy with spontaneous symmetry breaking. Topological field characteristics occur when formalizing gauge models by foliations.

1984-01-01

377

Ward identities in a general axial gauge. II. Quantum gravity  

Science.gov (United States)

We have calculated the pole part of the one-loop graviton self-energy in the noncovariant axial gauge n????=0, n2?0, where ??? is the physical gravition field and n? is an arbitrary but constant vector. It is shown that the self-energy is, unexpectedly, both nontransverse and n? dependent, even though it satisfies the correct gravitational Ward identity. This Ward identity is found to contain a term corresponding to a "pincer" Feynman diagram which is directly responsible for the nontransversality of the graviton self-energy. Ghost particles do not contribute to the graviton amplitude. All aixal-gauge integrals are consistently evaluated in the context of dimensional regularization and by applying the principal-value prescription.

Capper, D. M.; Leibbrandt, George

1982-02-01

378

On the axial anomalies in external tensor fields  

International Nuclear Information System (INIS)

[en] Computation of the axial anomaly for Dirac fermions in external tensor fields is studied. The sequence of the supersymmetric one-dimensional models is presented. Their supercharges are equal, after quantization, to Dirac operators in external tensor fields, and the density of Witten's partition function gives the anomaly. It is shown that action in the corresponding path integral differs from the classical one. Gaussian approximation gives the anomaly only in the case of third-rank tensor with zero exterior derivative and in that case anomaly is calculated in all dimensions. The interpretation of that field as the torsion of gravitational field and also connection with the results of Witten and Alvarez-Gaume and Atiyah-Singer index theorem are discussed

1985-01-01

379

Superconformal anomaly free models in D=4  

CERN Document Server

A family of modified $(0,1)$ heterotic string models in D=4 is constructed in which the strings are boundaries of Chern Simons 2-branes. These models have a cancellation mechanism for $R$ gauge anomalies so as to make local spacetime superconformal symmetry consistent with quantum mechanics. There is an intrinsic Goldstino multiplet, so that supersymmetry breaking can be driven by any process that generates a non-zero value for the superpotential. A relationship between the value of the bare coupling $g$ and the level zero spectrum follows from an analysis of the non-perturbative defect around a string. The superconformal anomaly freedom of these models may be related to a naturally vanishing $\\Lambda$.

Hewitt, M

2003-01-01

380

Physical Account of Weyl Anomaly from Dirac Sea  

CERN Multimedia

We derive the Weyl anomaly in two dimensional space-time by considering the Dirac sea regularized some negatively counted formally bosonic extra species.In fact we calculate the trace of the energy-momentum tensor of the Dirac sea in a background gravitational field. It has to be regularized, since otherwise the Dirac sea is bottomless and thus causes divergence. The new regularization method consists in adding various massive species some of which are to be counted negative in the Dirac sea.The mass term in the Lagrangian of the regularization fields have a dependence on the background gravitational field.

Habara, Y; Ninomiya, M

2012-01-01

 
 
 
 
381

Gravitational Interstellar Scintillation  

CERN Multimedia

Gravitation could modulate the interstellar scintillation of pulsars in a way that is analogous to refractive interstellar scintillation (RISS). While RISS occurs when a large ionized cloud crosses the pulsar line-of-sight, gravitational interstellar scintillation (GISS) occurs when a compact gravitational deflector lies very near to that line-of-sight. However, GISS differs from RISS in at least two important respects: It has a very distinctive and highly predictible time signature, and it is non-dispersive. We find two very different astronomical contexts where GISS could cause observable diffraction-pattern distortions: Highly inclined binary pulsars, and the kind of compact interstellar clouds suspected of causing extreme scattering events.

Fakir, Redouane Al

2008-01-01

382

Self-gravitating non-Abelian kinks as brane worlds  

International Nuclear Information System (INIS)

We address the properties of self-gravitating domain walls arising from the breaking of an SU(N)xZ2-symmetric theory. In the particular case of N=5, we find that the two classes of stable non-Abelian kinks possible in flat space, that break SU(5) to its maximal subgroups, have an analogue in the gravitational case, and construct the analytical solutions. Localization of fermion fields in different representations of the gauge group in these branes is investigated. It is also shown that non-Abelian gauge fields localization cannot be achieved through interactions with the brane, but that in one of the two classes of kinks this localization can be implemented via the Dvali-Shifman mechanism.

2011-07-15

383

Topological defects in gravitational theories with non linear Lagrangians  

CERN Multimedia

The gravitational field of monopoles, cosmic strings and domain walls is studied in the quadratic gravitational theory $R+\\alpha R^2$ with $\\alpha |R|\\ll 1$, and is compared with the result in Einstein's theory. The metric aquires modifications which correspond to a short range `Newtonian' potential for gauge cosmic strings, gauge monopoles and domain walls and to a long range one for global monopoles and global cosmic strings. In this theory the corrections turn out to be attractive for all the defects. We explain, however, that the sign of these corrections in general depends on the particular higher order derivative theory and topological defect under consideration. The possible relevance of our results to the study of the evolution of topological defects in the early universe is pointed out.

Audretsch, J; Loustó, C O

1993-01-01

384

Gauge mediation in supergravity and gravitino dark matter  

International Nuclear Information System (INIS)

Gravitinos and hidden sector fields often cause a cosmological disaster in supersymmetric models. We find that a model with gravitational gauge mediation solves such a problem quite naturally. The ?-problem is also absent in the model. Moreover, the abundance of gravitinos explains correct amount of dark matter of the universe. The dark matter abundance can be calculated without detailed information on the thermal history of the universe such as the reheating temperature after inflation.

2007-03-01

385

The harmonic gauge condition in the gravitomagnetic equations  

CERN Document Server

It has been asserted in the literature that the analogy between the linear and first order slow motion approximation of Einstein equations of General Relativity (gravitomagnetic equations) and the Maxwell-Lorentz equations of electrodynamics breaks down if the gravitational potentials are time dependent. In this work, we show that this assertion is not correct and it has arisen from an incorrect limit of the usual harmonic gauge condition, which drastically changes the physical content of the gravitomagnetic equations.

Pascual-Sánchez, J F

2000-01-01

386

A gauge theoretic approach to elasticity with microrotations  

CERN Document Server

We formulate elasticity theory with microrotations using the framework of gauge theories, which has been developed and successfully applied in various areas of gravitation and cosmology. Following this approach, we demonstrate the existence of particle-like solutions. Mathematically this is due to the fact the our equations of motion are of Sine-Gordon type and thus have soliton type solutions. Similar to Skyrmions and Kinks in classical field theory, we can show explicitly that these solutions have a topological origin.

Boehmer, Christian G

2010-01-01

387

Connecting anomaly and tunneling methods for the Hawking effect through chirality  

International Nuclear Information System (INIS)

The role of chirality is discussed in unifying the anomaly and the tunneling formalisms for deriving the Hawking effect. Using the chirality condition and starting from the familiar form of the trace anomaly, the chiral (gravitational) anomaly, manifested as a nonconservation of the stress tensor, near the horizon of a black hole, is derived. Solution of this equation yields the stress tensor whose asymptotic infinity limit gives the Hawking flux. Finally, use of the same chirality condition in the tunneling formalism gives the Hawking temperature that is compatible with the flux obtained by anomaly method.

2009-03-15

388

General gauge mediation  

International Nuclear Information System (INIS)

We give a general definition of gauge mediated supersymmetry breaking which encompasses all the known gauge mediation models. In particular, it includes both models with messengers as well as direct mediation models. A formalism for computing the soft terms in the generic model is presented. Such a formalism is necessary in strongly-coupled direct mediation models where perturbation theory cannot be used. It allows us to identify features of the entire class of gauge mediation models and to distinguish them from specific signatures of various subclasses. (author)

2009-01-01

389

Optical heat flux gauge  

Energy Technology Data Exchange (ETDEWEB)

A heat flux gauge comprising first and second thermographic phosphor layers separated by a layer of a thermal insulator wherein each thermographic layer comprises a plurality of respective thermographic phosphors. The gauge may be mounted on a surface with the first thermographic phosphor in contact with the surface. A light source is directed at the gauge, causing the phosphors to luminesce. The luminescence produced by the phosphors is collected and its spectra analyzed in order to determine the heat flux on the surface. First and second phosphor layers must be different materials to assure that the spectral lines collected will be distinguishable.

Noel, Bruce W. (Espanola, NM); Borella, Henry M. (Santa Barbara, CA); Cates, Michael R. (Oak Ridge, TN); Turley, W. Dale (Santa Barbara, CA); MacArthur, Charles D. (Clayton, OH); Cala, Gregory C. (Dayton, OH)

1991-01-01

390

Optical heat flux gauge  

Energy Technology Data Exchange (ETDEWEB)

A heat flux gauge comprising first and second thermographic phosphor layers separated by a layer of a thermal insulator. The gauge may be mounted on a surface with the first thermographic phosphor in contact with the surface. A light source is directed at the gauge, causing the phosphors to luminesce. The luminescence produced by the phosphors is collected and its spectra analyzed in order to determine the heat flux on the surface. First and second phosphor layers must be different materials to assure that the spectral lines collected will be distinguishable.

Noel, Bruce W. (Espanola, NM); Borella, Henry M. (Santa Barbara, CA); Cates, Michael R. (Oak Ridge, TN); Turley, W. Dale (Santa Barbara, CA); MaCarthur, Charles D. (Clayton, OH); Cala, Gregory C. (Dayton, OH)

1991-01-01

391

Optical heat flux gauge  

Energy Technology Data Exchange (ETDEWEB)

A heat flux gauge comprising first and second thermographic phosphor layers separated by a layer of a thermal insulator, wherein each thermographic layer comprises a plurality of respective thermographic sensors in a juxtaposed relationship with respect to each other. The gauge may be mounted on a surface with the first thermographic phosphor in contact with the surface. A light source is directed at the gauge, causing the phosphors to luminesce. The luminescence produced by the phosphors is collected and its spectra analyzed in order to determine the heat flux on the surface. First and second phosphor layers must be different materials to assure that the spectral lines collected will be distinguishable.

Noel, Bruce W. (Espanola, NM); Borella, Henry M. (Santa Barbara, CA); Cates, Michael R. (Oak Ridge, TN); Turley, W. Dale (Santa Barbara, CA); MacArthur, Charles D. (Clayton, OH); Cala, Gregory C. (Dayton, OH)

1991-01-01

392

Gauges, propagators, and physics  

CERN Document Server

When a theory shall be described at all scales, it is necessary to start from its elementary degrees of freedom. Herein, one possible chain of steps for this purpose will be briefly outlined for the example of a gauge theory, like QCD. Starting with the elementary constituents, gluons and quarks, step by step the final observables, physical states, will be built up. This process is based on the elementary correlation functions, and uses a combination of both numerical lattice calculations and functional continuum methods. While the process uses a fixed gauge at each intermediate step, the final observables are gauge-invariant.

Maas, Axel

2010-01-01

393

Gauge independence as a consequence of gauge covariance  

International Nuclear Information System (INIS)

Gauge independence of a physical S-matrix is proved without perturbation in a satisfactory gauge-field theory with gauge covariance. The proof goes through both for Abelian and non-Abelian cases, and the independence is a consequence of gauge covariance and asymptotic completeness. (auth.).

1978-01-01

394

Generalization of the regge-wheeler equation for self-gravitating matter fields  

UK PubMed Central (United Kingdom)

It is shown that the dynamical evolution of perturbations on a static spacetime is governed by a standard pulsation equation for the extrinsic curvature tensor. The centerpiece of the pulsation equation is a wave operator whose spatial part is manifestly self-adjoint. In contrast to metric formulations, the curvature-based approach to perturbation theory generalizes in a natural way to self-gravitating matter fields, including non-Abelian gauge fields and perfect fluids. As an example, the pulsation equations for self-gravitating, non-Abelian gauge fields are explicitly shown to be symmetric.

Brodbeck O; Heusler M; Sarbach O

2000-04-01

395

On the unified affine electromagnetism and gravitation theories  

International Nuclear Information System (INIS)

It is shown, by a different method than used originally, that the gauge theory proposed by Ferraris and Kijowski is an interacting gravitational and electromagnetic fields theory. Using a new method, the affine Lagrangians of the linear Maxwell-Einstein and of the Born-Infeld-Einstein electrodynamics are derived. Two theorems relating the affine and the matter Lagrangians for the electromagnetic field are proved. (author).

1984-01-01

396

Off shell one-loop divergences in gauged O(N) supergravities  

Energy Technology Data Exchange (ETDEWEB)

We present the expression for the off shell one-loop infinities in gauged O(N) supergravities thus explaining the agreement of two previous calculations of the gauge coupling ..beta..-function. The off shell gravitino contribution in the Weyl tensor squared divergence is found to have negative sign leading to the one-loop off shell finiteness of the N = 8 and N = 1, d = 10 ..-->.. 4 supergravities in the gravitational 2/sup +/-sector.

Fradkin, E.S.; Tseytlin, A.A. (AN SSSR, Moscow. Dept. of Theoretical Physics)

1982-11-18

397

[Iris racemose vascular anomalies  

UK PubMed Central (United Kingdom)

Authors present 7 rare iris racemose vascular anomalies that were discovered by biomicroscopy during routine ocular examination. The morphology, clinical features and iris circulation of these cases are documented by iris fluoroangiography. They also report common features, some specific details of arrangement and classification criteria. The iris vascular anomaly appears to be benign stationary condition that has none systemic and ocular associations.

Streicher T; Spirková J; Stubna M

2006-04-01

398

Gravitational clustering: an overview  

CERN Multimedia

We discuss the differences and analogies of gravitational clustering in finite and infinite systems. The process of collective, or violent, relaxation leading to the formation of quasi-stationary states is one of the distinguished features in the dynamics of self-gravitating systems. This occurs, in different conditions, both in a finite than in an infinite system, the latter embedded in a static or in an expanding background. We then discuss, by considering some simple and paradigmatic examples, the problems related to the definition of a mean-field approach to gravitational clustering, focusing on role of discrete fluctuations. The effect of these fluctuations is a basic issue to be clarified to establish the range of scales and times in which a collision-less approximation may describe the evolution of a self-gravitating system and for the theoretical modeling of the non-linear phase.

Labini, Francesco Sylos

2008-01-01

399

Gravitation with Two Times  

CERN Document Server

We investigate the possibility of constructing a covariant Newtonian gravitational theory and find that the action describing a massless relativistic particle in a background Newtonian gravitodynamic field has a higher-dimensional extension with two times.

Chagas-Filho, W

2006-01-01

400

On the gravitational redshift  

CERN Document Server

The study of the gravitational redshift -- a relative wavelength increase of $\\approx 2 \\times 10^{-6}$ was predicted for solar radiation by Einstein in 1908 -- is still an important subject in modern physics. In a dispute whether or not atom interferometry experiments can be employed for gravitational redshift measurements, two research teams have recently disagreed on the physical cause of the shift. Regardless of any discussion on the interferometer aspect -- we find that both groups of authors miss the important point that the ratio of gravitational to the electrostatic forces is generally very small. For instance, the gravitational force acting on an electron in a hydrogen atom situated in the Sun's photosphere to the electrostatic force between the proton and the electron is approximately $3 \\times 10^{-21}$. A comparison of this ratio with the predicted and observed solar redshift indicates a discrepancy of many orders of magnitude. Here we show, with Einstein's early assumption of the frequency of spe...

Wilhelm, Klaus

2013-01-01

 
 
 
 
401

Linear gravitational theories  

Energy Technology Data Exchange (ETDEWEB)

It is shown that linear metrical gravitational theory based on one tensor field of second order which satisfies the weak-equivalence principle is equivalent to, in linear approximation, general theory of relativity.

Pandey, S.N.; Finkelstein, A.M. (AN SSSR, Pulkovo. Special Astrophysical Observatory)

1983-10-15

402

Response of interferometric gravitational wave detectors  

International Nuclear Information System (INIS)

The derivation of the response function of an interferometric gravitational wave detector is a paradigmatic calculation in the field of gravitational wave detection. Surprisingly, the standard derivation of the response wave detectors makes several unjustifiable assumptions, both conceptual and quantitative, regarding the coordinate trajectory and coordinate velocity of the null geodesic the light travels along. These errors, which appear to have remained unrecognized for at least 35 years, render the standard derivation inadequate and misleading as an archetype calculation. Here we identify the flaws in the existing derivation and provide, in full detail, a correct derivation of the response of a single-bounce Michelson interferometer to gravitational waves, following a procedure that will always yield correct results; compare it to the standard, but incorrect, derivation; show where the earlier mistakes were made; and identify the general conditions under which the standard derivation will yield correct results. By a fortuitous set of circumstances, not generally so, the final result is the same in the case of Minkowski background spacetime, synchronous coordinates, transverse-traceless gauge metric perturbations, and arm mirrors at coordinate rest.

2009-01-15

403

Gravitation and Electricity  

Directory of Open Access Journals (Sweden)

Full Text Available The equations of gravitation together with the equations of electromagnetism in terms of the General Theory of Relativity allow to conceive an interdependence between the gravitational field and the electromagnetic field. However the technical difficulties of the relevant problems have precluded from expressing clearly this interdependence. Even the simple problem related to the field generated by a charged spherical mass is not correctly solved. In the present paper we reexamine from the outset this problem and propose a new solution.

Stavroulakis N.

2008-01-01

404

Quantum Foam, Gravity and Gravitational Waves  

CERN Multimedia

The new information-theoretic Process Physics has shown that space is a quantum foam system with gravity being, in effect, an inhomogeneous in-flow of the quantum foam into matter. The theory predicts that absolute motion with respect to this system should be observable, and it is shown here that absolute motion has been detected in at least seven experiments. As well this experimental data also reveals the existence of a gravitational wave phenomena associated with the in-flow. It is shown that Galilean Relativity and Special Relativity are in fact compatible, contrary to current beliefs: absolute motion actually causes the special relativity effects. The new theory of gravity passes all the tests of the previous Newtonian and General Relativity theories, but in addition resolves the numerous gravitational anomalies such as the spiral galaxy `dark matter' effect, the absence of `dark matter' in elliptical galaxies, the inconsistencies in measuring G, the borehole g anomaly, and others. It is shown that Newto...

Cahill, R T

2003-01-01

405

Holographic anomaly in 3D f(Ric) gravity  

Science.gov (United States)

By applying the holographic renormalization method to the metric formalism of f(Ric) gravity in three dimensions, we obtain the Brown–York boundary stress tensor for backgrounds which asymptote to the locally AdS3 solution of Einstein gravity. The logarithmic divergence of the on-shell action can be subtracted by a non-covariant cut-off-independent term which exchanges the trace anomaly for a gravitational anomaly. We show that the central charge can be determined by means of Banados–Teitelboim–Zanelli holography or in terms of the Hawking effect of a Schwarzschild black hole placed on the boundary.

Loran, Farhang

2013-10-01

406

Constructive gauge theory  

International Nuclear Information System (INIS)

[en] Here some insight is provided into mathematical methods to analyze quantized gauge theories. This approach is being used to establish existence as well as to prove properties of gauge field models. Up to now, only abelian gauge fields are known to exist, namely the U(1) Higgs model on IR2 and IR3 and electrodynamics on the tori T2 and T3. In these lectures infrared properties of some of these models as studied. The non-Abelian gauge models are interesting for additional reasons: First, they have a natural geometric interpretation. Furthermore, because of asymptotic freedom, non-Abelian models have better local regularity properties than Abelian theories. Furthermore, they provide a rich analytic structure. In these notes ultraviolet properties of the d = 3 Yang-Mills theory are described. The Euclidean point of view is used throughout. The connection to real time follows from established results. 17 references, 8 figures

1986-01-01

407

Extended gauge sectors  

International Nuclear Information System (INIS)

[en] Present and future prospects for the discovery of new gauge bosons, Z' and W', are reviewed. Particular attention is paid to hadron and e+e- collider searches for the W' of the Left-Right Symmetric Model

1995-01-01

408

Observables and gauge fixing in spontaneously broken gauge theories  

CERN Multimedia

Gauge fixing and the observable fields for both abelian and non-abelian gauge theories with spontaneous breaking of gauge symmetry are studied. We explicitly show that it is possible to globally fix the gauge in the broken sector and hence construct physical fields even in the non-abelian theory. We predict that any high temperature restoration of gauge symmetry will be accompanied by a confining transition.

Lavelle, M J; Lavelle, Martin; McMullan, David

1994-01-01

409

Parastatistics and gauge symmetries  

International Nuclear Information System (INIS)

[en] It is shown that the copy of the only SO(3) - gauge Yang-Mills Lagrangian can be constructed in the Green parafield theory. Thus, the Greenberg paraquarks are not equivalent to coloured quarks obeying SU(3)sub(c). Peculiarities of gauge SO(3) are considered and its possible application as the exact subgroup of the broken SU(3)sub(c) is indicated

1981-01-01

410

Parastatistics and gauge symmetries  

International Nuclear Information System (INIS)

[en] It is shown that the copy of the only SO(3)-gauge Yang-Mills Lagrangian can be constructed in the Green parafield theory. Thus the Greenberg paraquarks are not equivalent to coloured quarks obeying SU(3)sub(c). Peculiarities of gauge SO(3) are considered and its possible application as the exact subgroup of the broken SU(3)sub(c) is indicated

1982-01-01

411

Natural Poincare gauge model  

Energy Technology Data Exchange (ETDEWEB)

Because it acts on space-time and is not semisimple, the Poincare group cannot lead to a gauge theory of the usual kind. A candidate model is discussed which keeps itself as close as possible to the typical gauge scheme. Its field equations are the Yang-Mills equations for the Poincare group. It is shown that there exists no Lagrangian for these equations.

Aldrovandi, R.; Pereira, J.G.

1986-05-15

412

Induced gauge interactions revisited  

CERN Multimedia

It has been shown that the old-fashioned idea of Sakharov's induced gravity and gauge interactions in the "one-loop dominance" version works astonishingly well yielding reasonable parameters. It appears that induced coupling constants of gauge interactions of the standard model assume qualitatively realistic values. Moreover, it is possible to induce the Barbero--Immirzi parameter of canonical gravity from the fields entering the standard model.

Broda, Bogus?aw

2010-01-01

413

A well pressure gauge  

Energy Technology Data Exchange (ETDEWEB)

The pressure gauge contains a body and a measurement subassembly. It includes measurement and compensation pistons connected by a measurement spring, a relay with a closing contact and a zero indicator. In order to increase the operational reliability of the pressure gauge, it is equipped with an electromagnetic vibrator and hollow transmission shafts. The shafts are notched and are installed in bearings above and below an operational nut. An operational screw is positioned inside the shafts.

Gabdullin, T.G.; Belyshev, G.A.; Gumovskiy, A.K.; Zakirov, R.Z.; Zaleyev, Z.I.

1983-01-01

414

Gauge Theories on de Sitter space and Killing Vectors  

CERN Document Server

We provide a general method for studying a manifestly covariant formulation of $p$-form gauge theories on the de Sitter space. This is done by stereographically projecting the corresponding theories, defined on flat Minkowski space, onto the surface of a de Sitter hyperboloid. The gauge fields in the two descriptions are mapped by conformal Killing vectors allowing for a very transparent analysis and compact presentation of results. As applications, the axial anomaly is computed and the electric-magnetic duality is exhibited. Finally, the zero curvature limit is shown to yield consistent results.

Banerjee, R

2006-01-01

415

Matter and light wave interferometry in gravitational fields  

International Nuclear Information System (INIS)

[en] The phenomenon of quantum mechanical interference fringes for particles (neutron) travelling along different paths through the earth's gravitational field is discussed. An attempt is made to answer the question of describing such effects when the gravitational field is not simply Newtonian; and the full tensor character of gravitation comes into play. In the assumption of the 'semi-classical limit' the quantity of interest is the quantum mechanical phase accumulated by the travelling particle along its classical path. The idea of gauge variance is suggested by analogy with the equivalent problem in electrodynamics. Novel effects appear, such as gravity waves incident onto an interferometer; another interesting class of non-Newtonian situations has to do with rotational effects

1978-06-07

416

Gravitational self-force on a particle in circular orbit around a Schwarzschild black hole  

International Nuclear Information System (INIS)

We calculate the gravitational self-force acting on a pointlike particle of mass ?, set in a circular geodesic orbit around a Schwarzschild black hole. Our calculation is done in the Lorenz gauge: For given orbital radius, we first solve directly for the Lorenz-gauge metric perturbation using numerical evolution in the time domain; we then compute the (finite) backreaction force from each of the multipole modes of the perturbation; finally, we apply the 'mode-sum' method to obtain the total, physical self-force. The temporal component of the self-force (which is gauge invariant) describes the dissipation of orbital energy through gravitational radiation. Our results for this component are consistent, to within the computational accuracy, with the total flux of gravitational-wave energy radiated to infinity and through the event horizon. The radial component of the self-force (which is gauge dependent) is calculated here for the first time. It describes a conservative shift in the orbital parameters away from their geodesic values. We thus obtain the O(?) correction to the specific energy and angular momentum parameters (in the Lorenz gauge), as well as the O(?) shift in the orbital frequency (which is gauge invariant)

2007-03-15

417

Hawking radiation from dilatonic black holes via anomalies  

International Nuclear Information System (INIS)

Recently, Hawking radiation from a Schwarzschild-type black hole via a gravitational anomaly at the horizon has been derived by Robinson and Wilczek. Their result shows that, in order to demand general coordinate covariance at the quantum level to hold in the effective theory, the flux of the energy-momentum tensor required to cancel the gravitational anomaly at the horizon of the black hole is exactly equal to that of (1+1)-dimensional blackbody radiation at the Hawking temperature. In this paper, we attempt to apply the analysis to derive Hawking radiation from the event horizons of static, spherically symmetric dilatonic black holes with arbitrary coupling constant ?, and that from the rotating Kaluza-Klein (?=?(3)) as well as the Kerr-Sen (?=1) black holes via an anomalous point of view. Our results support Robinson and Wilczek's opinion. In addition, the properties of the obtained physical quantities near the extreme limit are qualitatively discussed.

2007-03-15

418

On the meaning of relativistic gravitational effects  

Energy Technology Data Exchange (ETDEWEB)

The authors review the empirical predictions of General Relativity in the light of the fact that the non inertialness of the observer has not been incorporated into this theory. The observations of the quantities related to the relativistic gravitational effects on the Solar System lead to the conclusion that the measured values may depend on the state of motion of the observer, whether it is accelerated or not. However, the `slowing-down` effect of gravity on the observer`s clock was not taken into account. They analyze the assumption which is used in order to explain the gravitational red-shift within the framework of General Relativity; their conclusion is that it is not compatible with the `slowing-down` effect of gravity on cesium atomic-beam clocks. They show that the measurements of a very small perihelion anomaly and the difference of orbital period between the Newtonian prediction and that of relativistic theories of gravity involve the observation of almost the same quantities. The advantage of the planetary orbital period is that they may show that what is thought to be constant may on a fine scale be changing. They exemplify this possibility by obtaining the orbital period predicted by General Relativity and that given within the framework of an alternative approach of gravity, which describes all the gravitational phenomena as viewed from inertial frames of reference.

Cavasso Filho, R. L.; Lucinda, J. [Parana`, Univ. Federal (Brazil). Dept. de Fisica

1998-01-01

419

Glueball Spectrum in a Gauge Theory with Two Dynamical Scales  

CERN Document Server

We investigate the glueball spectrum of a strongly coupled gauge theory with two dynamical scales. The main tool is the use of the gauge/gravity duality. The model we study has a known graviational dual, which arises from a type IIB D-brane configuration. It exhibits two dynamical scales, separated by a nearly conformal region. Thus, it is of great interest for the study of walking in gauge theories. By using the gravitational description, we are able to compute analytically the glueball mass spectrum. Our results differ in a significant way from previous numerical calculations, performed for this class of models. Namely, we do not find a light state that could be associated with slight breaking of conformal invariance. Finally, we show that in this model there can be an order of magnitude hierarchy between the scale of confinement, given by the lowest glueball mass, and the scale of chiral symmetry breaking, determined by the lowest vector-meson mass.

Anguelova, Lilia; Wijewardhana, L C Rohana

2012-01-01

420

Conformally invariant gauge conditions in electromagnetism and general relativity  

International Nuclear Information System (INIS)

The construction of conformally invariant gauge conditions for Maxwell and Einstein theories on a manifold M is found to involve two basic ingredients. First, covariant derivatives of a linear gauge (e.g. Lorenz or de Donder), completely contracted with the tensor field representing the metric on the vector bundle of the theory. Second, the addition of a compensating term, obtained by covariant differentiation of a suitable tensor field built from the geometric data of the problem. The existence theorem for such a gauge in gravitational theory is here proved when the manifold M is endowed with a m-dimensional positive-definite metric g. An application to a generally covariant integral formulation of the Einstein equations is also outlined.

2000-01-01

 
 
 
 
421

Green-Schwarz anomaly cancellation, world sheet instantons and wormholes  

International Nuclear Information System (INIS)

We consider the breaking of the global conservation of gauge field charges which are commonly thought to survive the spontaneous breakdown of gauge symmetry brought about by Kalb-Ramond fields. Depending on the dilaton field and also the size of the compactifying space, the global charge breaking may take place due to world sheet instantons. In going to 3+1 dimensions one could have a serious problem in order to produce the hierarchies between the quark and the charged lepton masses using the mass protecting charges with the Green-Schwartz anomaly cancellation. Various unnatural features of this type of models are discussed. (author)

2003-01-01

422

Quanta. Relativity. Gravitation  

International Nuclear Information System (INIS)

Proceedings of the 18 workshop on high energy physics and field theory are presented. The development of quantum theory is shown. General relativity and gauge theories are considered. The reports on particle physics (theory and experiments) are presented too.

1996-01-01

423

A first look at Weyl anomalies in shape dynamics  

CERN Multimedia

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 ($[\\Omega, \\Omega]\\propto \\hbar$ instead of vanishing) is given by a projection of the second ghost cohomology of the Hamiltonian BRST differential associated to $\\Omega$, modulo spatial derivatives. Assuming locality of the gauge cohomology groups involved, this part is always local. The temporal part, $[\\Omega, H]\\propto\\hbar$ is given by a different projection of the first ghost cohomology, local under the same assumptions, and an extra piece...

Gomes, Henrique

2013-01-01

424

Loop quantum gravity corrections to gravitational wave dispersion  

International Nuclear Information System (INIS)

Cosmological tensor perturbations equations are derived for Hamiltonian cosmology based on Ashtekar's formulation of general relativity, including typical quantum gravity effects in the Hamiltonian constraint as they are expected from loop quantum gravity. This translates to corrections of the dispersion relation for gravitational waves. The main application here is the preservation of causality which is shown to be realized due to the absence of anomalies in the effective constraint algebra used.

2008-01-15

425

Anode foundry production anomalies  

Energy Technology Data Exchange (ETDEWEB)

The production of aluminum anodes used for the cathodic protection of offshore structures and pipelines is a complex process. Various types of production anomalies have been observed during the inspection of these anodes. The anomalies were compiled over the past ten years and many of the examples occurred in foundries no longer producing anodes. They are noted in this paper to aid the reader in better understanding of the complexities of anode casting and to highlight some of the types of anomalies that can occur.

Johnson, D.L. [Sub Sea International Inc., Belle Chasse, LA (United States)

1997-09-01

426

Hydrodynamics with Triangle Anomalies  

CERN Document Server

We consider the hydrodynamic regime of theories with quantum anomalies for global currents. We show that a hitherto discarded term in the conserve current is not only allowed by symmetries, but is in fact required by triangle anomalies and the second law of thermodynamics. This term leads to a number of new effects, one of which is chiral separation in a rotating fluid at nonzero chemical potential. The new kinetic coefficients can be expressed, in a unique fashion, through the anomalies coefficients and the equation of state. We briefly discuss the relevance of this new hydrodynamic term for physical situations, including heavy ion collisions.

Son, Dam T

2009-01-01

427

Hydrodynamics with triangle anomalies.  

Science.gov (United States)

We consider the hydrodynamic regime of theories with quantum anomalies for global currents. We show that a hitherto discarded term in the conserved current is not only allowed by symmetries, but is in fact required by triangle anomalies and the second law of thermodynamics. This term leads to a number of new effects, one of which is chiral separation in a rotating fluid at nonzero chemical potential. The new kinetic coefficients can be expressed, in a unique fashion, through the anomaly coefficients and the equation of state. We briefly discuss the relevance of this new hydrodynamic term for physical situations, including heavy-ion collisions. PMID:20365915

Son, Dam T; Surówka, Piotr

2009-11-06

428

Hydrodynamics with triangle anomalies.  

UK PubMed Central (United Kingdom)

We consider the hydrodynamic regime of theories with quantum anomalies for global currents. We show that a hitherto discarded term in the conserved current is not only allowed by symmetries, but is in fact required by triangle anomalies and the second law of thermodynamics. This term leads to a number of new effects, one of which is chiral separation in a rotating fluid at nonzero chemical potential. The new kinetic coefficients can be expressed, in a unique fashion, through the anomaly coefficients and the equation of state. We briefly discuss the relevance of this new hydrodynamic term for physical situations, including heavy-ion collisions.

Son DT; Surówka P

2009-11-01

429

Anomalies on orbifolds  

Energy Technology Data Exchange (ETDEWEB)

We discuss the form of the chiral anomaly on an S1/Z2 orbifold with chiral boundary conditions. We find that the 4-divergence of the higher-dimensional current evaluated at a given point in the extra dimension is proportional to the probability of finding the chiral zero mode there. Nevertheless the anomaly, appropriately defined as the five dimensional divergence of the current, lives entirely on the orbifold fixed planes and is independent of the shape of the zero mode. Therefore long distance four dimensional anomaly cancellation ensures the consistency of the higher dimensional orbifold theory.

Arkani-Hamed, Nima; Cohen, Andrew G.; Georgi, Howard

2001-03-16

430

Constraining an Expanding Locally Anisotropic metric from the Pioneer anomaly  

CERN Document Server

It is discussed the possibility of a fine-tuneable contribution to the two way Doppler acceleration either towards, either outwards the Sun for heliocentric distances above 20 AU by considering a background described by an Expanding Locally Anisotropic (ELA) metric. This metric encodes both the standard local Schwarzschild gravitational effects and the cosmological Universe expansion effects allowing simultaneously to fine-tune other gravitational effects at intermediate scales, which may be tentatively interpreted as a covariant parameterization of either cold dark matter either gravitational interaction corrections. Are derived bounds for the ELA metric functional parameter by considering the bounds on the deviation from standard General Relativity imposed by the current updated limits for the Pioneer anomaly, taking in consideration both the natural outgassing and on-board radiation pressure, resulting in an average Doppler acceleration outwards the Sun of a_p = +0.4^{+2.1}_{-2.0} x 10^{-10} (m/s^2). It is...

Ferreira, P Castelo

2012-01-01

431

Unambiguous spin-gauge formulation of canonical general relativity with conformorphism invariance  

International Nuclear Information System (INIS)

We present a parameter-free gauge formulation of general relativity in terms of a new set of real spin connection variables. The theory is constructed by extending the phase space of the recently formulated conformal geometrodynamics to accommodate a spin-gauge description. This leads to a further enlarged set of first class gravitational constraints consisting of a reduced Hamiltonian constraint and the canonical generators for spin-gauge and conformorphism transformations. Owing to the incorporated conformal symmetry, the new theory is shown to be free from an ambiguity of the Barbero-Immirzi type.

2005-10-15

432

How to adapt broad-band gravitational-wave searches for r-modes  

International Nuclear Information System (INIS)

Up to now there has been no search for gravitational waves from the r-modes of neutron stars in spite of the theoretical interest in the subject. Several oddities of r-modes must be addressed to obtain an observational result: The gravitational radiation field is dominated by the mass current (gravitomagnetic) quadrupole rather than the usual mass quadrupole, and the consequent difference in polarization affects detection statistics and parameter estimation. To astrophysically interpret a detection or upper limit it is necessary to convert the gravitational-wave amplitude to an r-mode amplitude. Also, it is helpful to know indirect limits on gravitational-wave emission to gauge the interest of various searches. Here I address these issues, thereby providing the ingredients to adapt broad-band searches for continuous gravitational waves to obtain r-mode results. I also show that searches of existing data can already have interesting sensitivities to r-modes.

2010-11-15

433

Energy Momentum Pseudo-Tensor of Relic Gravitational Wave in Expanding Universe  

CERN Document Server

We study the energy-momentum pseudo-tensor of gravitational wave, and examine the one introduced by Landau-Lifshitz for a general gravitational field and the effective one recently used in literature. In short wavelength limit after Brill-Hartle average, both lead to the same gauge invariant stress tensor of gravitational wave. For relic gravitational waves in the expanding universe, we examine two forms of pressure, $p_{gw}$ and $\\mathcal{P}_{gw}$, and trace the origin of their difference to a coupling between gravitational waves and the background matter. The difference is shown to be negligibly small for most of cosmic expansion stages starting from inflation. We demonstrate that the wave equation is equivalent to the energy conservation equation using the pressure $\\mathcal{P}_{gw}$ that includes the mentioned coupling.

Su, Daiqin

2012-01-01

434

Canonical transformations and the gauge dependence in general gauge theories  

Energy Technology Data Exchange (ETDEWEB)

Gauge-invariant renormalizability is proven for a general gauge theory with an arbitrary gauge condition. It is shown that a canonical change of the variables in the initial effective action generates just a canonical change of the variables in the renormalized action and in the vertex generating functional. It is noted that the gauge condition enters the effective action as a canonical transformation. As a consequence, a change of the gauge condition is equivalent to the canonical transformation of the renormalized action and the vertex generating functional and this fact, in turn, leads to the gauge invariance of the renormalized S matrix.

Voronov, B.L. (AN SSSR, Moscow. Fizicheskij Inst.); Lavrov, P.M. (Tomskij Pedagogicheskij Inst. (USSR)); Tyutin, I.V. (AN SSSR, Tomsk. Inst. Sil' notochnoj Ehlektroniki)

1982-01-01

435

Canonical transformations and the gauge dependence in general gauge theories  

Energy Technology Data Exchange (ETDEWEB)

A proof is given of the gauge-invariant renormalizability of general gauge theories in arbitrary gauges. We show that a canonical change of variables in the initial effective action also generates only a canonical change of variables in the renormalized action and in the vertex generating functional. We note that the gauge condition enters into the effective action as a canonical transformation. As a consequence, changing the gauge condition is equivalent to a canonical transformation of the renormalized action and the vertex generating functional. This, in turn, implies the gauge invariance of the renormalized S matrix.

Voronov, B.L.; Lavrov, P.M.; Tyutin, I.V.

1982-08-01

436

Gauge/Gravity Duality (Gauge Gravity Duality)  

Energy Technology Data Exchange (ETDEWEB)

Gauge theories, which describe the particle interactions, are well understood, while quantum gravity leads to many puzzles. Remarkably, in recent years we have learned that these are actually dual, the same system written in different variables. On the one hand, this provides our most precise description of quantum gravity, resolves some long-standing paradoxes, and points to new principles. On the other, it gives a new perspective on strong interactions, with surprising connections to other areas of physics. I describe these ideas, and discuss current and future directions.

Polchinski, Joseph (Kavli Institute for Theoretical Physics)

2010-02-24

437

Phases of Gauge Theories  

CERN Document Server

One of the most fundamental questions we can ask about a given gauge theory is its phase diagram. In the standard model, we observe three fundamentally different types of behavior: QCD is in a confined phase at zero temperature, while the electroweak sector of the standard model combines Coulomb and Higgs phases. Our current understanding of the phase structure of gauge theories owes much to the modern theory of phase transitions and critical phenomena, but has developed into a subject of extensive study. After reviewing some fundamental concepts of phase transitions and finite-temperature gauge theories, we discuss some recent work that broadly extends our knowledge of the mechanisms that determine the phase structure of gauge theories. A new class of models with a rich phase structure has been discovered, generalizing our understanding of the confinement-deconfinement transition in finite-temperature gauge theories. Models in this class have space-time topologies with one or more compact directions. On R^3 ...

Ogilvie, Michael C

2012-01-01

438

'Gauging' the fluid  

CERN Multimedia

A consistent framework has been put forward to quantize the isentropic, compressible and inviscid fluid model in the Hamiltonian framework using the Clebsch parametrization. The naive quantization is hampered by the non-canonical (in particular, field dependent) Poisson bracket algebra. To overcome this problem, the Batalin-Tyutin (1992 Int. J. Mod. Phys. A 6 3255) quantization formalism is adopted in which the original system is converted to a local gauge theory and is embedded in a canonical extended phase space. In a different reduced phase-space scheme (Mitra P and Rajaraman R 1990 Ann. Phys., NY 203 157, Anishetty R and Vytheeswaran A S 1993 J. Phys. A: Math. Gen. 26 5613) also, the original model is converted to a gauge theory and subsequently the two distinct gauge invariant formulations of the fluid model are related explicitly. This strengthens the equivalence between the relativistic membrane (where a gauge invariance is manifest) and the fluid (where the gauge symmetry is hidden). Relativistic gene...

Ghosh, S

2002-01-01

439

Kohn anomaly in graphene  

International Nuclear Information System (INIS)

[en] Symmetry based analysis of the Kohn anomaly is performed. Kohn phonon frequencies and displacements are calculated by force constant method. It is shown that Kohn phonon vibrations cause electronic band gap opening.

2011-04-15

440

Tachyons in gravitational field  

International Nuclear Information System (INIS)

[en] Behaviour of tachyons in gravitational field has been investigated by using imaginary as well as real superluminal Lorentz transformations. Using real superluminal transformations in four- and six-dimensional space-time, an expression for the gravitational force acting on a tachyon, moving along the tachyon corridor constructed to follow the tachyon geodesic, has been derived. The motion of a tachyon through a black hole has also been discussed and it is shown that the black hole acts like a gravitational tunnel for tachyons and the transition between the regions inside and outside the horizon can be understood as real superluminal transformations transforming a R4=(r,t) world into a T4=(t,r) world. 36 refs.. (author)

1986-01-01

 
 
 
 
441

A Gedankenexperiment in Gravitation  

CERN Document Server

In this paper we consider a thought experiment involving the effect of gravitation on an ideal scale containing a photon. If the tidal forces inherent to a gravitational field are neglected, then one is led to scenario which seems to bring about perpetual motion violating the first and second principle of thermodynamics. The tidal effects of gravity must neccessarily be included in order to obtain a consistent physical theory. As a result, Albert Einstein's thought experiments according to which the physical effects of inertia in an accelerated reference frame are equivalent to the effects of gravity in a frame at rest on the surface of a massive body must be reconsidered, since linearly accelerated frames do not produce tidal effects. We argue that the equivalence between inertial effects and gravitation can be restored for rotating frames and in this context a relation with the possible nature of quantum gravity is conjectured.

Gaspar, Yves

2011-01-01

442

Gravitation and spacetime  

CERN Document Server

The third edition of this classic textbook is a quantitative introduction for advanced undergraduates and graduate students. It gently guides students from Newton's gravitational theory to special relativity, and then to the relativistic theory of gravitation. General relativity is approached from several perspectives: as a theory constructed by analogy with Maxwell's electrodynamics, as a relativistic generalization of Newton's theory, and as a theory of curved spacetime. The authors provide a concise overview of the important concepts and formulas, coupled with the experimental results underpinning the latest research in the field. Numerous exercises in Newtonian gravitational theory and Maxwell's equations help students master essential concepts for advanced work in general relativity, while detailed spacetime diagrams encourage them to think in terms of four-dimensional geometry. Featuring comprehensive reviews of recent experimental and observational data, the text concludes with chapters on cosmology an...

Ohanian, Hans C

2013-01-01

443

Complexification of Gauge Theories  

CERN Multimedia

For the case of a first-class constrained system with an equivariant momentum map, we study the conditions under which the double process of reducing to the constraint surface and dividing out by the group of gauge transformations $G$ is equivalent to the single process of dividing out the initial phase space by the complexification $G_C$ of $G$. For the particular case of a phase space action that is the lift of a configuration space action, conditions are found under which, in finite dimensions, the physical phase space of a gauge system with first-class constraints is diffeomorphic to a manifold imbedded in the physical configuration space of the complexified gauge system. Similar conditions are shown to hold in the infinite-dimensional example of Yang-Mills theories. As a physical application we discuss the adequateness of using holomorphic Wilson loop variables as (generalized) global coordinates on the physical phase space of Yang-Mills theory.

Loll, R; Tavares, J N

1996-01-01

444

Large Gauge Ward Identity  

CERN Document Server

We study the question of the Ward identity for "large" gauge invariance in 0+1 dimensional theories. We derive the relevant Ward identities for a single flavor fermion and a single flavor complex scalar field interacting with an Abelian gauge field. These identities are nonlinear. The Ward identity for any other complicated theory can be derived from these basic sets of identities. However, the structure of the Ward identity changes since these are nonlinear identities. In particular, we work out the "large" gauge Ward identity for a supersymmetric theory involving a single flavor of fermion as well as a complex scalar field. Contrary to the effective action for the individual theories, the solution of the Ward identity in the supersymmetric theory involves an infinity of Fourier component modes. We comment on which features of this analysis are likely/unlikely to generalize to the 2+1 dimensional theory.

Das, A; Frenkel, J; Das, Ashok; Dunne, Gerald

2000-01-01

445

Expanding impulsive gravitational waves  

CERN Multimedia

We explicitly demonstrate that the known solutions for expanding impulsive spherical gravitational waves that have been obtained by a "cut and paste" method may be considered to be impulsive limits of the Robinson-Trautman vacuum type N solutions. We extend these results to all the generically distinct subclasses of these solutions in Minkowski, de Sitter and anti-de Sitter backgrounds. For these we express the solutions in terms of a continuous metric. Finally, we also extend the class of spherical shock gravitational waves to include a non-zero cosmological constant.

Podolsky, J

1999-01-01

446

Supersymmetry and Gravitational Duality  

CERN Multimedia

We study how the supersymmetry algebra copes with gravitational duality. As a playground, we consider a charged Taub-NUT solution of D=4, N=2 supergravity. We find explicitly its Killing spinors, and the projection they obey provides evidence that the dual magnetic momenta necessarily have to appear in the supersymmetry algebra. The existence of such a modification is further supported using an approach based on the Nester form. In the process, we find new expressions for the dual magnetic momenta, including the NUT charge. The same expressions are then rederived using gravitational duality.

Argurio, Riccardo; Houart, Laurent

2008-01-01

447

Jacobi identity anomaly in closed string field theory  

International Nuclear Information System (INIS)

[en] The Jacobi identity, which is an indispensable property for gauge invariant closed string field theory, is apparently broken in cases where one of the four legs of the identity has vanishing string-length. This phenomenon contradicts the general proof of the identity valid at the critical dimension. We examine the general proof and clarify the mechanism of this Jacobi identity anomaly. (author)

1991-01-01

448

Transgressions and Holographic Conformal Anomalies for Chern-Simons Gravities  

CERN Multimedia

I present two calculations of the holographic Weyl anomalies induced by Chern-Simons gravity theories alternative to the ones presented in the literature. The calculations presented here rest on the extension from Chern-Simons to Transgression forms as lagrangians, motivated by gauge invariance, which automatically yields the boundary terms suitable to regularize the theory. The procedure followed here sheds light in the structure of Chern-Simons gravities and their regularization.

Mora, Pablo

2010-01-01

449

Cubic curves from matrix models and generalized Konishi anomalies  

CERN Document Server

We study the matrix model/gauge theory connection for three different N=1 models: U(N) x U(N) with matter in bifundamental representations, U(N) with matter in the symmetric representation, and U(N) with matter in the antisymmetric representation. Using Ward identities, we explicitly show that the loop equations of the matrix models lead to cubic algebraic curves. We then establish the equivalence of the matrix model and gauge theory descriptions in two ways. First, we derive generalized Konishi anomaly equations in the gauge theories, showing that they are identical to the matrix-model equations. Second, we use a perturbative superspace analysis to establish the relation between the gauge theories and the matrix models. We find that the gauge coupling matrix for U(N) with matter in the symmetric or antisymmetric representations is_not_ given by the second derivative of the matrix-model free energy. However, the matrix-model prescription can be modified to give the gauge coupling matrix.

Naculich, S G; Wyllard, N

2003-01-01

450

Cubic curves from matrix models and generalized Konishi anomalies  

Science.gov (United States)

We study the matrix model/gauge theory connection for three different Script N = 1 models: U(N) × U(N) with matter in bifundamental representations, U(N) with matter in the symmetric representation, and U(N) with matter in the antisymmetric representation. Using Ward identities, we explicitly show that the loop equations of the matrix models lead to cubic algebraic curves. We then establish the equivalence of the matrix model and gauge theory descriptions in two ways. First, we derive generalized Konishi anomaly equations in the gauge theories, showing that they are identical to the matrix-model equations. Second, we use a perturbative superspace analysis to establish the relation between the gauge theories and the matrix models. We find that the gauge coupling matrix for U(N) with matter in the symmetric or antisymmetric representations is not given by the second derivative of the matrix-model free energy. However, the matrix-model prescription can be modified to give the gauge coupling matrix.

Naculich, Stephen G.; Schnitzer, Howard J.; Wyllard, Niclas

2003-08-01

451

Exploring General Gauge Mediation  

CERN Multimedia

We explore various aspects of General Gauge Mediation(GGM). We present a reformulation of the correlation functions used in GGM, and further elucidate their IR and UV properties. Additionally we clarify the issue of UV sensitivity in the calculation of the soft masses in the MSSM, highlighting the role of the supertrace over the messenger spectrum. Finally, we present weakly coupled messenger models which fully cover the parameter space of GGM. These examples demonstrate that the full parameter space of GGM is physical and realizable. Thus it should be considered a valid basis for future phenomenological explorations of gauge mediation.

Buican, Matthew; Seiberg, Nathan; Shih, David

2009-01-01

452

Wild Quiver Gauge Theories  

CERN Document Server

We study N=2 supersymmetric SU(2) gauge theories coupled to non-Lagrangian superconformal field theories induced by compactifying the six dimensional A_1 (2,0) theory on Riemann surfaces with irregular punctures. These are naturally associated to Hitchin systems with wild ramification whose spectral curves provide the relevant Seiberg-Witten geometries. We propose that the prepotential of these gauge theories on the Omega-background can be obtained from the corresponding irregular conformal blocks on the Riemann surfaces via a generalization of the coherent state construction to the case of higher order singularities.

Bonelli, Giulio; Tanzini, Alessandro

2011-01-01

453

Gauge-theory ghosts and ghost-gauge theories  

International Nuclear Information System (INIS)

The geometric unitarity equations for an Internal gauge theory, for a supergauge, for the Kalb Ramond field, and for a Non-Internal gauge are reviewed. Recent results relating to the role of antighosts are presented.

1981-01-01

454

Neutrino Phenomenology of gauged L?--L?: MINOS and beyond  

International Nuclear Information System (INIS)

If a Z'gauge boson from a gauged L?--L? symmetry is very light, it is associated with a long-range leptonic force. In this case the particles in the Sun create via mixing of the Z'with the Standard Model Z a flavor-dependent potential for muon neutrinos in terrestrial long-baseline experiments. The potential changes sign for anti-neutrinos and hence can lead to apparent differences in neutrino and anti-neutrino oscillations without introducing CP or CPT violation. This could for instance explain the recently found discrepancy in the MINOS experiment. We obtain the associated parameters of gauged L?--L? required to explain this anomaly. The consequences for future long-baseline experiments are also discussed, and we compare the scenario to standard NSIs. When used to explain MINOS, both approaches have severe difficulties with existing limits.

2011-10-06

455

Gauge/Cosmology Brane-to-Brane Duality  

CERN Document Server

We introduce a duality relation between two distinct branes, a cosmological brane with macroscopic matter and a holographic brane with microscopic gauge fields. Using brane-world cosmology with a single brane in a 5-dimensional AdS5 background, we find an explicit time-dependent holographic correspondence between the bulk metric surrounding the cosmological brane and the N=4 gauge field theory living on the boundary of the Z2-symmetric mirror bulk, identified with the holographic brane. We then relate the cosmic acceleration on the cosmological brane to the conformal anomaly of the gauge theory on the holographic brane. This leads to a dual microscopic interpretation of the number of e-foldings of the cosmological eras on the cosmological brane.

Brax, Philippe

2010-01-01

456

Gauging of Virasoro and w-infinity and Beltrami parametrization  

International Nuclear Information System (INIS)

The two-dimensional conformal field theory has Virasoro algebra as the underlying symmetry. This algebra can be used to describe the coupling of two-dimensional gravity to matter and can be generalized at w-infinity algebra to describe w-gravity. In this paper the gauging of the Virasoro and w-infinity algebras is discussed from the point of view of BRST symmetry. Both algebras are realized as 'Russian formulas' for the curvatures built from the generators of the Lie algebra and the corresponding gauge fields and ghosts. The generalized curvatures are used to determine the gauge invariant Lagrangians as well as the anomaly structures of the conformal two-dimensional theory and the w-gravity. (Author)

1992-01-01

457

Gauge symmetries and fibre bundles  

International Nuclear Information System (INIS)

The matter is organized as follows. After a brief introduction to the concept of gauge invariance and its relationship to determinism, we introduce in chapters 3 and 4 the notion of fibre bundles in the context of a discussion on spinning point particles and Dirac monopoles. Chapter 3 deals with a non relativistic treatment of the spinning particle. The non trivial extension to relativistic spinning particles is dealt with in Chapter 5. The free particle system as well as interactions with external electromagnetic and gravitational fields are discussed in detail. In chapter 5 we also elaborate on a remarkable relationship between the charge-monopole system and the system of a massless particle with spin. The classical description of Yang-Mills particles with internal degrees of freedom, such as isospin or colour, is given in chapter 6. We apply the above in a discussion of the classical scattering of particles off a 't Hooft-Polyakov monopole. In chapter 7 we elaborate on a Kaluza-Klein description of particles with internal degrees of freedom. The canonical formalism and the quantization of most of the preceeding systems are discussed in chapter 8. The dynamical systems given in chapters 3-7 are formulated on group manifolds. The procedure for obtaining the extension to super-group manifolds is briefly discussed in chapter 9. In chapter 10, we show that if a system admits only local Lagrangians for a configuration space Q, then under certain conditions, it admits a global Lagrangian when Q is enlarged to a suitable U(1) bundle over Q. Conditions under which a symplectic form is derivable from a Lagrangian are also found. (orig./HSI)

1983-01-01

458

Note on the evolution of the gravitational potential in Rastall scalar field theories  

International Nuclear Information System (INIS)

We investigate the evolution of the gravitational potential in Rastall scalar field theories. In a single component model a consistent perturbation theory, formulated in the Newtonian gauge, is possible only for ?=1, which is the General Relativity limit. On the other hand, the addition of another canonical fluid component allows to consider the case ??1.

2012-05-15

459

Note on the evolution of the gravitational potential in Rastall scalar field theories  

Energy Technology Data Exchange (ETDEWEB)

We investigate the evolution of the gravitational potential in Rastall scalar field theories. In a single component model a consistent perturbation theory, formulated in the Newtonian gauge, is possible only for {gamma}=1, which is the General Relativity limit. On the other hand, the addition of another canonical fluid component allows to consider the case {gamma}{ne}1.

Fabris, J.C., E-mail: fabris@pq.cnpq.br [Departamento de Fisica, Universidade Federal do Espirito Santo, avenida Ferrari 514, 29075-910 Vitoria, Espirito Santo (Brazil); Hamani Daouda, M., E-mail: daoudah8@yahoo.fr [Departamento de Fisica, Universidade Federal do Espirito Santo, avenida Ferrari 514, 29075-910 Vitoria, Espirito Santo (Brazil); Piattella, O.F., E-mail: oliver.piattella@ufes.br [Departamento de Fisica, Universidade Federal do Espirito Santo, avenida Ferrari 514, 29075-910 Vitoria, Espirito Santo (Brazil)

2012-05-15

460

Note on the Evolution of the Gravitational Potential in Rastall Scalar Field Theories  

CERN Multimedia

We investigate the evolution of the gravitational potential in Rastall scalar field theories. In a single component model a consistent perturbation theory, formulated in the newtonian gauge, is possible only for $\\gamma = 1$, which is the General Relativity limit. On the other hand, the addition of another canonical fluid component allows also to consider the case $\\gamma \

Fabris, J C; Piattella, O F

2011-01-01

 
 
 
 
461

Anomalies of hidden local chiral symmetries in sigma-models and extended supergravities  

International Nuclear Information System (INIS)

Non-linear sigma-models with hidden gauge symmetries are anomalous, at the quantum level, when coupled to chiral fermions in not anomaly free representations of the hidden chiral symmetry. These considerations generally apply to supersymmetric kaehlerian sigma-models on coset spaces with hidden chiral symmetries as well as to extended supergravities in four dimensions with local SU(N) symmetry. The presence of the anomaly implies that the scenario of dynamical generation of gauge vector bosons has to be reconsidered in these theories. (orig.).

1985-01-01

462

Comment on gauge conditions in non-Abelian gauge theories  

International Nuclear Information System (INIS)

Gauge conditions in non-Abelian gauge theories are considered studying unitarity with a given Lagrangian with various linear gauge conditions and using the usual formalism for constructing the fictitious Lagrangian. The results show that even with the fulfillment of certain requirements the theory may have difficulties

1976-01-01

463

Gravitational observables, intrinsic coordinates, and canonical maps  

CERN Document Server

It is well known that in a generally covariant gravitational theory the choice of spacetime scalars as coordinates yields phase-space observables (or "invariants"). However their relation to the symmetry group of diffeomorphism transformations has remained obscure. In a symmetry-inspired approach we construct invariants out of canonically induced active gauge transformations. These invariants may be intepreted as the full set of dynamical variables evaluated in the intrinsic coordinate system. The functional invariants can explicitly be written as a Taylor expansion in the coordinates of any observer, and the coefficients have a physical and geometrical interpretation. Surprisingly, all invariants can be obtained as limits of a family of canonical transformations. This permits a short (again geometric) proof that all invariants, including the lapse and shift, satisfy Poisson brackets that are equal to the invariants of their corresponding Dirac brackets.

Pons, J M; Sundermeyer, K A

2009-01-01

464

Gauge fields beyond perturbation theory  

CERN Document Server

A new formulation of nonabelian gauge theories, introducing new ghost fields and new symmetry is proposed. This formulation does not suffer from Gribov ambiguity and allows to quantize nonabelian gauge fields beyond perturbation theory.

Slavnov, A A

2013-01-01

465

Search for gravitational waves  

International Nuclear Information System (INIS)

This article serves as an introduction to the sources of gravitational waves and their detection. The types of sources expected to generate signals detectable by instruments currently planned, together with the theory governing these detectors, are considered. Order of magnitude estimates for the characteristic wave amplitudes are calculated and compared to the sensitivities of the currently prototyped and future detectors.

1988-01-01

466

Search for gravitational waves  

Energy Technology Data Exchange (ETDEWEB)

This article serves as an introduction to the sources of gravitational waves and their detection. The types of sources expected to generate signals detectable by instruments currently planned, together with the theory governing these detectors, are considered. Order of magnitude estimates for the characteristic wave amplitudes are calculated and compared to the sensitivities of the currently prototyped and future detectors.

Tinto, M.

1988-12-01

467

Introduction to Gravitational Microlensing  

CERN Multimedia

The basic concepts of gravitational microlensing are introduced. We start with the lens equation, and then derive the image positions and magnifications. The statistical quantities of optical depth and event rate are then described. We finish with a summary and a list of challenges and open questions. A problem set is given for students to practice.

Mao, Shude

2008-01-01

468

Quasars and gravitational lenses  

Energy Technology Data Exchange (ETDEWEB)

The proceedings from the 24th Liege astrophysics meeting on quasars are given. The topics discussed include: detection of quasars, VLBI observations of quasars and superluminal motions, gravitational lenses, distribution of quasars and observational cosmology, associations, physics of quasars and quasar absorption lines.

1983-01-01

469

Colliding plane gravitational waves  

Energy Technology Data Exchange (ETDEWEB)

Exact solutions of Einstein's field equations for colliding gravitational pp waves are analysed and reviewed using a new approach. A general method is given for deriving solutions in which the approaching waves have constant aligned polarisation. Two new solutions are presented.

Griffiths, J.B.

1987-07-01

470

Alternative equations of gravitation  

International Nuclear Information System (INIS)

[en] It is shown, trough a new formalism, that the quantum fluctuation effects of the gravitational field in Einstein's equations are analogs to the effects of a continuum medium in Maxwell's Electrodynamics. Following, a real example of the applications of these equations is studied. Qunatum fluctuations effects as perturbation sources in Minkowski and Friedmann Universes are examined. (L.C.)

1983-01-01

471

300 Years of Gravitation  

Science.gov (United States)

This text was written in commemoration of the 300th anniversary of Newton's Philosophiae Naturalis Principia Mathematica and provides numerous review papers written about gravity. The papers cover the problems with Newtonian gravity and the main principles of modern gravitational theory, including general relativity, black holes, inflationary cosmology, dark matter, and string theory unification.

2009-06-15

472

Gravitational production of gravitinos  

CERN Document Server

We calculate the number density of helicity $\\pm3/2$ gravitinos produced out of the vacuum by the non-static gravitational field in a generic inflation scenario. We compare it to the number density of gravitinos produced in particle interactions during reheating.

Lemoine, M

1999-01-01

473

Gravitational waves signal analysis  

CERN Document Server

I use a very simplified example to discuss the signature of a gravitational wave taking into account the relative state of motion of the detector with respect to the source that originated it. Something that to my knowledge has been ignored up to now and may ruin the best crafted template \\cite{Templates}.

Bel, Ll

2012-01-01

474

Generalized plane gravitational waves  

Energy Technology Data Exchange (ETDEWEB)

The definition of plane gravitational waves is generalized to include the case in which rays are not orthogonal to the two-dimensional wave surfaces. All Einstein spaces and some new solutions of the Einstein-Maxwell equations of this type are given.

Kellner, A.

1981-06-01

475

Electromagnetism and gravitation.  

UK PubMed Central (United Kingdom)

Generation of electric fields in rapidly rotating insulators is discussed and calculated. An interesting effect is expected in TlCl. A possible appearance of magnetic fields near rapidly rotating gravitating bodies is proposed. The simple suggestion made here would lead to magnetic fields of negligible magnitude.

Teller E

1977-07-01

476

Thermally favourable gauge mediation  

International Nuclear Information System (INIS)

We discuss the thermal evolution of the spurion and messenger fields of ordinary gauge mediation models taking into account the Standard Model degrees of freedom. It is shown that for thermalized messengers the metastable susy breaking vacuum becomes thermally selected provided that the susy breaking sector is sufficiently weakly coupled to messengers or to any other observable field.

2011-03-14

477

On the unitary gauge  

International Nuclear Information System (INIS)

[en] A rigorous treatment of the unitary gauge in the SU(2) Yang-Mills-Higgs system is given. It is shown that the massive vector fields give a long-range contribution along the negative z axis corresponding to the string in the electromagnetic field. (author)

1977-01-01

478

Charges in Gauge Theories  

Directory of Open Access Journals (Sweden)

Full Text Available Recent progress in the construction of both electric, coloured and magnetic charges in gauge theories will be presented. The topological properties of the charged sectors will be highlighted as well as the applications of this work to confinement and infrared dynamics.

David McMullan

2007-01-01

479

Extended gauge sectors  

Energy Technology Data Exchange (ETDEWEB)

Present and future prospects for the discovery of new gauge bosons, Z{prime} and W{prime}, are reviewed. Particular attention is paid to hadron and e{sup +}e{sup {minus}} collider searches for the W{prime} of the Left-Right Symmetric Model.

Rizzo, T.G.

1995-02-01

480

More on generalized gauge hierarchies  

International Nuclear Information System (INIS)

We point out that the generalized gauge hierarchy evolution equation of Dawson and Georgi for the gauge coupling constants of the subgroups of a unifying group should be modified in order to make it applicable to all the unifying groups. We modify their formula, and in the process derive a formula relating the gauge couplings of the subgroups and the gauge coupling of the unifying group at the unification mass scale. (author)

1982-01-01

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