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1

Topological meaning of gauge and gravitational anomalies and Gaussian factors

International Nuclear Information System (INIS)

We discuss a relation between the 2n-dimensional anomalies and the (2n+2)-dimensional chiral anomalies using the Gaussian factor (heat kernel) regularization. Recently, it was shown that Fujikawa's form of the non-Abelian anomaly is related to a topological object in a direct manner. Their argument seems general and independent of concrete forms of index, anomaly and other details of models. In this paper we extend the analysis to the V, A coupling gauge theories, the gravitational theory and also to the open superstring theory. In application to the gravitational anomaly, we obtain a family of consistent anomalies from the higher dimensional index, which are all equivalent to Fujikawa's form. Our construction of gravitational anomalies leads naturally to counterterms which relate different forms of anomalies to one another. In the case of Type-I superstring theory in 10 dimensions, we show that the gauge anomaly in this theory is related to a index of a kind of Dirac operator in 12 dimensions. Our consideration might provide hints to geometrical understanding of string anomaly. (author)

2

Gauge and gravitational anomalies in D=4 N=1 orientifolds.

Digital Repository Infrastructure Vision for European Research (DRIVER)

We analyze in detail the cancellation of U(1)-gauge and U(1)-gravitational anomalies in certain D=4 N=1 Type IIB orientifolds, from a string theory point of view. We verify the proposal that these anomalies are cancelled by a Green-Schwarz mechanism involving only twisted RR fields. By factorizing one-loop partition functions, we also get the RR couplings of D-branes and O-planes to theses fields. Twisted sectors with fixed planes participate to the inflow mechanism in a peculiar way.SR416082...

1999-01-01

3

Gauge and gravitational anomalies in D=4 N=1 orientifolds

Digital Repository Infrastructure Vision for European Research (DRIVER)

We analyze in detail the cancellation of U(1)-gauge and U(1)-gravitational anomalies in certain D=4 N=1 Type IIB orientifolds, from a string theory point of view. We verify the proposal that these anomalies are cancelled by a Green-Schwarz mechanism involving only twisted RR fields. By factorizing one-loop partition functions, we also get the RR couplings of D-branes and O-planes to theses fields. Twisted sectors with fixed planes participate to the inflow mechanism in a peculiar way.SR416082...

Scrucca, C. A.; Serone, M.

1999-01-01

4

Classical gauge gravitation theory

Digital Repository Infrastructure Vision for European Research (DRIVER)

Classical gravitation theory is formulated as gauge theory on natural bundles where gauge symmetries are general covariant transformations and a gravitational field is a Higgs field responsible for their spontaneous symmetry breaking.

Sardanashvily, G.

2011-01-01

5

Gravitational Anomaly and Transport

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

6

Fivebrane Gravitational Anomalies

Digital Repository Infrastructure Vision for European Research (DRIVER)

Freed, Harvey, Minasian and Moore have proposed a mechanism to cancel the gravitational anomaly of the M-theory fivebrane coming from diffeomorphisms acting on the normal bundle. This procedure is based on a modification of the conventional M-theory Chern-Simons term. We compactify this space-time interaction to the ten-dimensional type IIA theory. We then analyze the relation to the anomaly cancellation mechanism for the type IIA fivebrane proposed by Witten.

Becker, Katrin; Becker, Melanie

1999-01-01

7

Gravitational Anomaly and Transport

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

Landsteiner, Karl; Megias, Eugenio; Pena-benitez, Francisco

2011-01-01

8

Thermodynamics, gravitational anomalies and cones

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

9

Holographic Gravitational Anomaly in First and Second Order Hydrodynamics

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

10

Fluid/Gravity Correspondence, Second Order Transport and Gravitational Anomaly*,**

Directory of Open Access Journals (Sweden)

Full Text Available We study the transport properties of a relativistic fluid affected by chiral and gauge-gravitational anomalies. The computation is performed in the framework of the fluid/gravity correspondence for a 5 dim holographic model with Chern-Simons terms in the action. We find new anomalous and non anomalous transport coefficients, as well as new contributions to the existing ones coming from the mixed gauge-gravitational anomaly. Consequences for the shear waves dispersion relation are analyzed.

Megías Eugenio

2014-03-01

11

Gravitational anomaly and transport phenomena.

Quantum anomalies give rise to new transport phenomena. In particular, a magnetic field can induce an anomalous current via the chiral magnetic effect and a vortex in the relativistic fluid can also induce a current via the chiral vortical effect. The related transport coefficients can be calculated via Kubo formulas. We evaluate the Kubo formula for the anomalous vortical conductivity at weak coupling and show that it receives contributions proportional to the gravitational anomaly coefficient. The gravitational anomaly gives rise to an anomalous vortical effect even for an uncharged fluid. PMID:21797593

Landsteiner, Karl; Megías, Eugenio; Pena-Benitez, Francisco

2011-07-01

12

Gravitational Anomaly and Transport Phenomena

International Nuclear Information System (INIS)

Quantum anomalies give rise to new transport phenomena. In particular, a magnetic field can induce an anomalous current via the chiral magnetic effect and a vortex in the relativistic fluid can also induce a current via the chiral vortical effect. The related transport coefficients can be calculated via Kubo formulas. We evaluate the Kubo formula for the anomalous vortical conductivity at weak coupling and show that it receives contributions proportional to the gravitational anomaly coefficient. The gravitational anomaly gives rise to an anomalous vortical effect even for an uncharged fluid.

13

During the last five decades, gravity, as one of the fundamental forces of nature, has been formulated as a gauge field theory of the Weyl-Cartan-Yang-Mills type. The resulting theory, the Poincar\\'e gauge theory of gravity, encompasses Einstein's gravitational theory as well as the teleparallel theory of gravity as subcases. In general, the spacetime structure is enriched by Cartan's torsion and the new theory can accommodate fermionic matter and its spin in a perfectly natural way. The present reprint volume contains articles from the most prominent proponents of the theory and is supplemented by detailed commentaries of the editors. This guided tour starts from special relativity and leads, in its first part, to general relativity and its gauge type extensions a la Weyl and Cartan. Subsequent stopping points are the theories of Yang-Mills and Utiyama and, as a particular vantage point, the theory of Sciama and Kibble. Later, the Poincar\\'e gauge theory and its generalizations are explored and specific topi...

Blagojevi?, Milutin

2012-01-01

14

Comment on gravitational anomalies

International Nuclear Information System (INIS)

It is shown by the path integral method that the general coordinate and local Lorentz anomalies satisfy certain relations between them. The physical meaning of the cancellation of those two anomalies is clarified and it is illustrated for the fields (psi, psi sub(?), Fsub(a)) in d = 2. We show that the use of local counter terms can be avoided if one adopts a non-linear realization of general coordinate transformations. The field representation (such as psi sub(?) and psisub(a)) dependence of the local Lorentz anomaly is also noted. (author)

15

Gravitational anomaly and transport phenomena

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 coefficie...

Landsteiner, Karl

2011-01-01

16

Holographic Gravitational Anomaly and Chiral Vortical Effect

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

17

Review on possible gravitational anomalies

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

18

Review on possible gravitational anomalies

Energy Technology Data Exchange (ETDEWEB)

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, Xavier E [Centro de Investigacion y Estudios Avanzados, CINVESTAV, Dept. of Physics, Av. IPN 2508, 07000 Ciudad de Mexico, D.F. (Mexico)

2005-01-15

19

Gravitational Instantons from Gauge Theory

A gauge theory can be formulated on a noncommutative (NC) spacetime. This NC gauge theory has an equivalent dual description through the so-called Seiberg-Witten (SW) map in terms of an ordinary gauge theory on a commutative spacetime. We show that all NC U(1) instantons of Nekrasov-Schwarz type are mapped to ALE gravitational instantons by the exact SW map and that the NC gauge theory of U(1) instantons is equivalent to the theory of hyper-Kaehler geometries. It implies the remarkable consequence that ALE gravitational instantons can emerge from local condensates of purely NC photons.

Yang, H S; Salizzoni, Mario; Yang, Hyun Seok

2006-01-01

20

Gravitational Instantons from Gauge Theory

A gauge theory can be formulated on a noncommutative (NC) spacetime. This NC gauge theory has an equivalent dual description through the so-called Seiberg-Witten (SW) map in terms of an ordinary gauge theory on a commutative spacetime. We show that all NC U(1) instantons of Nekrasov-Schwarz type are mapped to asymptotically locally Euclidean (ALE) gravitational instantons by the exact SW map and that the NC gauge theory of U(1) instantons is equivalent to the theory of hyper-Kähler geometries. It implies the remarkable consequence that ALE gravitational instantons can emerge from local condensates of purely NC photons.

Yang, Hyun Seok; Salizzoni, Mario

2006-05-01

21

Gravitation and Gauge Symmetries

Energy Technology Data Exchange (ETDEWEB)

The purpose of this book (I quote verbatim from the back cover) is to 'shed light upon the intrinsic structure of gravity and the principle of gauge invariance, which may lead to a consistent unified field theory', a very laudable aim. The content divides fairly clearly into four sections (and origins). After a brief introduction, chapters 2-6 review the 'Structure of gravity as a theory based on spacetime gauge symmetries'. This is fairly straightforward material, apparently based on a one-semester graduate course taught at the University of Belgrade for about two decades, and, by implication, this is a reasonably accurate description of its level and assumed knowledge. There follow two chapters of new material entitled 'Gravity in flat spacetime' and 'Nonlinear effects in gravity'. The final three chapters, entitled 'Supersymmetry and supergravity', 'Kaluza-Klein theory' and 'String theory' have been used for the basis of a one-semester graduate course on the unification of fundamental interactions. The book concludes with thirteen appendices, covering mainly technical issues but also including Ashtekhar variables and Chern-Simons theory. Irritatingly, there is a separate bibliography for each chapter (which leads to much duplication) but commendably, the author highlights selected sources for suitable further reading. Also to be welcomed wholeheartedly are well-chosen worked examples and exercises, ranging from easy to fairly challenging, in each chapter. This is a properly bound paperback, hardly inexpensive, but well up to IOP's impeccable production standards. Could this be the ideal textbook for a research student or even an established researcher from another field to pick up the latest developments in field theory? Unfortunately this is not the whole story. The back cover also asserts, while talking about gauge invariance, that 'It is less known that the principle of equivalence, one of the basic dynamical properties of the gravitational interaction, can be expressed as a (spacetime) gauge symmetry'. On page 10 this is qualified to be a local symmetry. On pages 62-3 this hidden result is revealed. As every relativist knows, the principle of equivalence implies that for each spacetime point p a chart (normal coordinates at p) can be chosen so that the metric tensor takes its Minkowski value and its (partial) derivatives vanish at p. In other words every (pseudo-)Riemannian manifold is locally flat, the 'less known' result. So what else can the author tell us about gravity? There is little to fault in the first two sections of the book, trying to express gravity as a nonlinear spin-2 theory on Minkowski spacetime, apart from the obvious objection. A well-known and highly-recommendable textbook by S Weinberg 1972 Gravitation and Cosmology (New York: Wiley), carries out, at a more elementary level, a similar programme with the same defect. Such local theories cannot predict global changes whereby spacetime has a different topology to the Minkowski one. (The unconvinced reader should investigate references to black holes in Weinberg's text.) As speaker after speaker at the S W Hawking 60th Birthday Conference last week emphasized, when trying to unify gravity with quantum theory, it is perilous to neglect geometry. Because the later chapters on supersymmetry, supergravity, Kaluza-Klein and string theories are more fashionable, I need to point out an important caveat. Excluding textbooks and conference volumes, all (English language) citations in the supersymmetry/supergravity chapter are at least 16 years old. Apart from one 2000 article (on teleparallel theory) this age gap drops by three years for the chapter on Kaluza-Klein theory, and it does not change any further for the string theory chapter. There have been more recent significant advances in our understanding and interpretation of these theories but, alas, they are not chronicled here. I raised a question as to the value of this book at the end of the first pa

Stewart, John M

2002-03-07

22

Gravitation and Gauge Symmetries

International Nuclear Information System (INIS)

The purpose of this book (I quote verbatim from the back cover) is to 'shed light upon the intrinsic structure of gravity and the principle of gauge invariance, which may lead to a consistent unified field theory', a very laudable aim. The content divides fairly clearly into four sections (and origins). After a brief introduction, chapters 2-6 review the 'Structure of gravity as a theory based on spacetime gauge symmetries'. This is fairly straightforward material, apparently based on a one-semester graduate course taught at the University of Belgrade for about two decades, and, by implication, this is a reasonably accurate description of its level and assumed knowledge. There follow two chapters of new material entitled 'Gravity in flat spacetime' and 'Nonlinear effects in gravity'. The final three chapters, entitled 'Supersymmetry and supergravity', 'Kaluza-Klein theory' and 'String theory' have been used for the basis of a one-semester graduate course on the unification of fundamental interactions. The book concludes with thirteen appendices, covering mainly technical issues but also including Ashtekhar variables and Chern-Simons theory. Irritatingly, there is a separate bibliography for each chapter (which leads to much duplication) but commendably, the author highlights selected sources for suitable further reading. Also to be welcomed wholeheartedly are well-chosen worked examples and exercises, ranging from easy to fairly challenging, in each chapter. This is aly challenging, in each chapter. This is a properly bound paperback, hardly inexpensive, but well up to IOP's impeccable production standards. Could this be the ideal textbook for a research student or even an established researcher from another field to pick up the latest developments in field theory? Unfortunately this is not the whole story. The back cover also asserts, while talking about gauge invariance, that 'It is less known that the principle of equivalence, one of the basic dynamical properties of the gravitational interaction, can be expressed as a (spacetime) gauge symmetry'. On page 10 this is qualified to be a local symmetry. On pages 62-3 this hidden result is revealed. As every relativist knows, the principle of equivalence implies that for each spacetime point p a chart (normal coordinates at p) can be chosen so that the metric tensor takes its Minkowski value and its (partial) derivatives vanish at p. In other words every (pseudo-)Riemannian manifold is locally flat, the 'less known' result. So what else can the author tell us about gravity? There is little to fault in the first two sections of the book, trying to express gravity as a nonlinear spin-2 theory on Minkowski spacetime, apart from the obvious objection. A well-known and highly-recommendable textbook by S Weinberg 1972 Gravitation and Cosmology (New York: Wiley), carries out, at a more elementary level, a similar programme with the same defect. Such local theories cannot predict global changes whereby spacetime has a different topology to the Minkowski one. (The unconvinced reader should investigate references to black holes in Weinberg's text.) As speaker after speaker at the S W Hawking 60th Birthday Conference last week emphasized, when trying to unify gravity with quantum theory, it is perilous to neglect geometry. Because the later chapters on supersymmetry, supergravity, Kaluza-Klein and string theories are more fashionable, I need to point out an important caveat. Excluding textbooks and conference volumes, all (English language) citations in the supersymmetry/supergravity chapter are at least 16 years old. Apart from one 2000 article (on teleparallel theory) this age gap drops by three years for the chapter on Kaluza-Klein theory, and it does not change any further for the string theory chapter. There have been more recent significant advances in our understanding and interpretation of these theories but, alas, they are not chronicled here. I raised a question as to the value of this book at the end of the first paragraph, and I want to answer it within the context of the

23

Gravitational instantons from gauge theory

Digital Repository Infrastructure Vision for European Research (DRIVER)

A gauge theory can be formulated on a noncommutative (NC) spacetime. This NC gauge theory has anequivalent dual description through the so-called Seiberg-Witten (SW) map in terms of an ordinary gauge theory on a commutative spacetime. We show that all NC U(1) instantons of Nekrasov-Schwarz type are mapped to asymptotically locally Euclidean (ALE) gravitational instantons by the exact SW map and thatthe NC gauge theory of U(1) instantons is equivalent to the theory of hyper-Kõhler geometries....

Salizzoni, Mauro

2006-01-01

24

Gravitational Lorentz anomaly from the overlap formula in 2-dimensions

In this letter we show that the overlap formulation of chiral gauge theories correctly reproduces the gravitational Lorentz anomaly in 2-dimensions. This formulation has been recently suggested as a solution to the fermion doubling problem on the lattice. The well known response to general coordinate transformations of the effective action of Weyl fermions coupled to gravity in 2-dimensions can also be recovered.

Randjbar-Daemi, S; Randjbar-Daemi, S; Strathdee, J

1995-01-01

25

Anomaly cancellation condition in lattice gauge theory

International Nuclear Information System (INIS)

We show that, to all orders of powers of the gauge potential, a gauge anomaly ? defined on 4-dimensional infinite lattice can always be removed by a local counterterm, provided that ? depends smoothly and locally on the gauge potential and that ? reproduces the gauge anomaly in the continuum theory in the classical continuum limit: The unique exception is proportional to the anomaly in the continuum theory. This follows from an analysis of nontrivial local solutions to the Wess-Zumino consistency condition in lattice gauge theory. Our result is applicable to the lattice chiral gauge theory based on the Ginsparg-Wilson Dirac operator, when the gauge field is sufficiently weak parallel-U(n,?) - 1-parallel < ?', where U(n,?) is the link variable and ?' a certain small positive constant. (author)

26

Gravitation and Gauge Symmetries

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

27

The ABJ anomaly in regularized gauge theories

Energy Technology Data Exchange (ETDEWEB)

We analyse the triangular anomaly in Pauli-Villars regularized axial U(1) gauge theory and within the Standard Model, using well-defined euclidean functional integrals. In axial U(1) gauge theory, we prove the presence of the anomaly and explain its relation to the IR non-analyticity of the fermion triangle. In the electroweak sector of the Standard Model, we confirm the cancelation of the anomaly to one-loop order in the regularized theory. We expose the theoretical tools based on which we aim to extend this result to all loop orders.

Leveque, Benjamin; Kopper, Christoph [Centre de Physique Theorique, Ecole Polytechnique (France)

2012-07-01

28

Group actions and anomalies in gauge theories

International Nuclear Information System (INIS)

The transformation properties are studied of the vacuum functional W(A) for chiral fermions in a gauge potential A under the group G x U(1) x R+ of gauge, chiral and scale transformations. The vacuum functional W is identified with a section of a G x U(1) x R+ line bundle over the space A of all gauge potentials. Known results on bundles carrying group actions give a simple and unifying clue to non-abelian, abelian chiral anomalies, as well as to trace anomalies. While the first are due to the twisting of a line bundle on A/G, the abelian chiral and trace anomalies are related to characters of U(1) and R+ respectively. Characters of U(1) are basically controlled by ''winding numbers''. i.e. again by topology. Opposite to these, trace anomalies seem to have little to do with topology, with the exception of two-dimensional theories. (orig.)

29

Fluid/Gravity Correspondence, Second Order Transport and Gravitational Anomaly***

We study the transport properties of a relativistic fluid affected by chiral and gauge-gravitational anomalies. The computation is performed in the framework of the fluid/gravity correspondence for a 5 dim holographic model with Chern-Simons terms in the action. We find new anomalous and non anomalous transport coefficients, as well as new contributions to the existing ones coming from the mixed gauge-gravitational anomaly. Consequences for the shear waves dispersion relation are analyzed. Talk given by E. Megías at the International Nuclear Physics Conference INPC 2013, 2-7 June 2013, Firenze, Italy.Supported by Plan Nacional de Altas Energías (FPA2009-07908, FPA2011-25948), Spanish MICINN Consolider-Ingenio 2010 Programme CPAN (CSD2007-00042), Comunidad de Madrid HEP-HACOS S2009/ESP-1473, Spanish MINECO's Centro de Excelencia Severo Ochoa Program (SEV-2012-0234, SEV-2012-0249), and the Juan de la Cierva Program.

Megías, Eugenio; Pena-Benitez, Francisco

2014-03-01

30

Gravitational Lorentz anomaly from the overall formula in 2-dimensions

International Nuclear Information System (INIS)

In this letter we show that the overlap formulation of chiral gauge theories correctly reproduces the gravitational Lorentz anomaly in 2-dimensions. This formulation has been recently suggested as a solution to the fermion doubling problem on the lattice. The well known response to general coordinate transformations of the effective action of Weyl fermions coupled to gravity in 2-dimensions can also be recovered. (author). 7 refs

31

Global gravitational anomaly cancellation for five-branes

We show that the global mixed gauge-gravitational anomaly of the worldvolume theory of the M5-brane vanishes, when the anomaly inflow from the bulk is taken into account. This result extends to the type IIA and heterotic E8 x E8 five-branes. As a by-product, we provide a definition of the chiral fermionic fields for generic non-spin M5-brane worldvolume and determine the coupling between the self-dual field and the M-theory C-field.

Monnier, Samuel

2013-01-01

32

Interpretation of Venus gravitational anomalies

International Nuclear Information System (INIS)

The Venus gravity field anomalies are interpreted from three harmonics of potential expansion. Masses and depths of the anomaly centers in three regions: the Aphrodita land, the Ishtar land and in the South of the planet, are defined from the Venus geoid height, pure anomaly of attractive force, and plumb deviation. These depths are determined to be 930-1140 km. Analogous Earth anomalies in the field smoothing from 16 to 3 harmonics are characterized by depth overestimation. 1.4-times. Because of this, depths of the Venus anomaly sources reduced to 16 harmonics lie approximately in the range of 700-800 km, that is they correspond to the depth of bedding of the Venus mantle second phase boundary

33

Gauge dependence of effective gravitational field

The problem of gauge independent definition of effective gravitational field is considered from the point of view of the process of measurement. Effective Slavnov identities for the generating functionals of Green functions corresponding to a system of arbitrary gravitational field measured by a single classical scalar field are obtained. These identities are used for explicit evaluation of the total contribution to the gauge dependent part of the one-loop effective apparatus action. It is shown that the non-local part of this contribution, describing gauge dependence of the long-range quantum corrections to the effective equations of motion of the apparatus, is absent. This result leads to the natural definition of gauge independent effective gravitational field in terms characterizing motion of the measuring device. We show, however, that the whole quantum contribution is gauge dependent due to generally non-vanishing local part originating from space-time regions where sources for the gravitational field a...

Kazakov, K A; Kazakov, Kirill A.; Pronin, Petr I.

2000-01-01

34

Gauge Symmetries and Holographic Anomalies of Chern-Simons and Transgression AdS Gravity

We review the issue of gauge and gravitational anomalies with backgrounds, maybe offering a new outlook on some aspects of these questions. We compute the holographic anomalies of hypothetical theories dual, in the sense of the AdS-CFT correspondence, to Chern-Simons AdS gravities. Those anomalies are either gauge anomalies associated to the AdS gauge group of the theory or diffeomorphism anomalies, with each kind related to the other. As a result of using suitable action principles por Chern-Simons AdS gravities, coming from Transgression forms, we obtain finite results without the need for further regularization. Our results are of potential interest for Lovelock gravity theories, as it has been shown that the boundary terms dictated by the transgressions for Chern-Simons gravities are also suitable to regularize Lovelock theories. The Wess-Zumino consistency condition ensures that anomalies of the generic form computed here should appear for these and other theories.

Mora, Pablo

2014-01-01

35

Gauge Anomalies and Neutrino Seesaw Models

Despite the success of the Standard Model concerning theoretical predictions, there are several experimental results that cannot be explained and there are reasons to believe that there exists new physics beyond it. Neutrino oscillations, and hence their masses, are examples of this. Experimentally it is known that neutrinos masses are quite small, when compared to all Standard Model particle masses. Among the theoretical possibilities to explain these tiny masses, the seesaw mechanism is a simple and well-motivated framework. In its minimal version, heavy particles are introduced that decouple from the theory in the early universe. To build consistent theories, classical symmetries need to be preserved at quantum level, so that there are no anomalies. The cancellation of these anomalies leads to constraints in the parameters of the theory. One attractive solution is to realize the anomaly cancellation through the modication of the gauge symmetry. In this thesis we present a short review of some features of t...

Neves Cebola, Luis Manuel

36

Cosmological meaning of the gravitational gauge group

It is shown that under a Kaluza--Klein-like ansatz, the de Sitter group as the gravitational gauge group can choose the only one model that may avert the big-bang singularity by torsion under certain assumptions, in a class of gravitational models with quadratic torsion terms.

Lu, Jia-An

2014-01-01

37

Noncommutative chiral gravitational anomalies in two dimensions

Scientific Electronic Library Online (English)

Full Text Available SciELO Mexico | Language: English Abstract in spanish Se examinan las anomalías gravitacionales en un espacio no conmutativo. El análisis es general e independiente de alguna teoría de gravedad no conmutativa específica y depende sólo de cómo la gravedad se acople a los fermiones quirales. El cálculo de Delbourgo-Salam de la correccción gravitacional a [...] la anomalía axial ABJ se estudia en detalle en este contexto. Finalmente se muestra que la anomalía gravitacional en dos dimensiones no admite correcciones no conmutativas en el parámetro ?. Abstract in english Gravitational anomalies in a noncommutative space are examined. The analysis is generic and independent of a particular noncommutative theory of gravity, and it depends only on how gravity is noncommutatively coupled to chiral fermions. Delbourgo-Salam computation of the gravitational correction of [...] the axial ABJ-anomaly is studied in detail in this context. Finally, we show that the two-dimensional gravitational anomaly does not permit noncommutative corrections in the parameter ?.

H, García-Compeán; C, Soto-Campos.

2007-02-01

38

Gravitation as Gauge theory of Poincare Group

International Nuclear Information System (INIS)

The geometrical approach to gauge theories, based on fiber-bundles, is shown in detail. Several gauge formalisms for gravitation are examined. In particular, it is shown how to build gauge theories for non-semisimple groups. A gravitational theory for the Poincare group, with all the essential characteristics of a Yang-Mills theory is proposed. Inonu-Wigner contractions of gauge theories are introduced, which provide a Lagrangian formalism, equivalent to a Lagrangian de Sitter theory supplemented by weak constraints. Yang and Einstein theories for gravitation become particular cases of a Yang-Mills theory. The classical limit of the proposed formalism leads to the Poisson equation, for the static case. (Author)

39

Conformal anomalies and the gravitational effective action: The TJJ correlator for a Dirac fermion

International Nuclear Information System (INIS)

We compute in linearized gravity all the contributions to the gravitational effective action due to a virtual Dirac fermion, related to the conformal anomaly. This requires, in perturbation theory, the identification of the gauge-gauge-graviton vertex off mass shell, involving the correlator of the energy-momentum tensor and two vector currents (TJJ), which is responsible for the generation of the gauge contributions to the conformal anomaly in gravity. We also present the anomalous effective action expanded in the inverse mass of the fermion as in the Euler-Heisenberg case.

40

Background Geometry in Gauge Gravitation Theory

Digital Repository Infrastructure Vision for European Research (DRIVER)

Dirac fermion fields are responsible for spontaneous symmetry breaking in gauge gravitation theory because the spin structure associated with a tetrad field is not preserved under general covariant transformations. Two solutions of this problem can be suggested. (i) There exists the universal spin structure $S\\to X$ such that any spin structure $S^h\\to X$ associated with a tetrad field $h$ is a subbundle of the bundle $S\\to X$. In this model, gravitational fields correspond ...

Sardanashvily, G.

1997-01-01

41

Higher order symmetries: covariant approach and quantum gravitational anomalies

International Nuclear Information System (INIS)

Full text: (author)The higher order symmetries are investigated in a covariant Hamiltonian formulation. The covariant phase-space approach is extended to include the presence of external gauge fields and scalar potentials. The special role of the Killing-Yano tensors is pointed out. Some non-trivial examples involving Runge-Lenz type conserved quantities are explicitly worked out. The relationship between hidden symmetries in a curved space background and the corresponding quantum operators that commute with the fundamental wave operator in a first-quantized field theory is investigated. It is shown that the conformal Killing tensors do not in general produce symmetry operators for the Klein-Gordon equation. In the case of the standard Killing tensors under a few notable favorable circumstances the existence of such operators is possible. However conformal Killing tensors are sources of gravitational anomalies even if they are square of conformal Killing-Yano tensors

42

Further study of global gauge anomalies of simple groups

International Nuclear Information System (INIS)

We generalize results of our previous studies for global gauge anomalies of simple Lie groups in even-dimensional space D=2n. Assuming the absence of local anomalies, we first show that any real (or orthogonal) representation has no global anomaly in D==2,4,6 (mod 8), and that the pseudoreal (or symplectic) one is free of global anomalies in D==0,2,6 (mod 8). Second, we prove that the SU(3) group has no global anomalies in any even dimension and neither does SU(4) in D==4 (mod 8)

43

Anomaly cancellation condition in abelian lattice gauge theories

International Nuclear Information System (INIS)

We analyze the general solution of the Wess-Zumino consistency condition in abelian lattice gauge theories, without taking the classical continuum limit. We find that, if the anomaly density is a local pseudo-scalar field on the lattice, the non-trivial anomaly is always proportional to the anomaly coefficient in the continuum theory. The possible extension of this result to non-abelian theories is briefly discussed. (author)

44

A New Anomaly-Free Gauged Supergravity in Six Dimensions

We present a new anomaly-free gauged N=1 supergravity model in six dimensions. The gauge group is $E_7 \\times G_2 \\times U(1)_R$, with all hyperinos transforming in the product representation {56,14). The theory admits monopole compactifications to $R^4 \\times S^2$, leading to D=4 effective theories with broken supersymmetry and massless fermions.

Avramis, S D; Randjbar-Daemi, S; Avramis, Spyros D.; Kehagias, Alex

2005-01-01

45

A new anomaly-free gauged supergravity in six dimensions

International Nuclear Information System (INIS)

We present a new anomaly-free gauged N = 1 supergravity model in six dimensions. The gauge group is E7 - G2 x U(1)R, with all hyperinos transforming in the product representation (56, 14). The theory admits monopole compactifications to R4 x S2, leading to D = 4 effective theories with broken supersymmetry and massless fermions. (author)

46

Hawking radiation for non-asymptotically flat dilatonic black holes using gravitational anomaly

Energy Technology Data Exchange (ETDEWEB)

The d-dimensional scalar field action may be reduced, in the background geometry of a black hole, to a two-dimensional effective action. In the near-horizon region, it appears a gravitational anomaly: the energy-momentum tensor of the scalar field is not conserved anymore. This anomaly is removed by introducing a term related to the Hawking temperature of the black hole. Even if the temperature term introduced is not covariant, a gauge transformation may restore the covariance. We apply this method to compute the temperature of the dilatonic non-asymptotically flat black holes. We compare the results with those obtained through other methods. (orig.)

Fabris, J.C. [Universidade Federal do Espirito Santo, Departamento de Fisica, Vitoria, Espirito Santo (Brazil); Marques, G.T. [Universidade Federal Rural da Amazonia-Brazil, ICIBE-LASIC, Belem, Para (Brazil)

2012-12-15

47

Harada–Tsutsui gauge recovery procedure: From Abelian gauge anomalies to the Stueckelberg mechanism

International Nuclear Information System (INIS)

Revisiting a path-integral procedure developed by Harada and Tsutsui for recovering gauge invariance from anomalous effective actions, it is shown that there are two ways to achieve gauge symmetry: one already presented by the authors, which is shown to preserve the anomaly in the sense of standard current conservation law, and another one which is anomaly-free, preserving current conservation. It is also shown that the application of the Harada–Tsutsui technique to other models which are not anomalous but do not exhibit gauge invariance allows the identification of the gauge invariant formulation of the Proca model, also done by the referred authors, with the Stueckelberg model, leading to the interpretation of the gauge invariant map as a generalization of the Stueckelberg mechanism. -- Highlights: • A gauge restoration technique from Abelian anomalous models is discussed. • It is shown that there is another way that leads to gauge symmetry restoration from such technique. • It is shown that the first gauge restoration preserves the anomaly, while the proposed second one is free from anomalies. • It is shown that the proposed gauge symmetry restoration can be identified with the Stueckelberg mechanism

48

The hexagon gauge anomaly in Type 1 superstring theory

International Nuclear Information System (INIS)

Hexagon diagrams with external on-mass-shell Yang-Mills gauge particles are investigated in Type I superstring theory. Both the annulus and the Mobius-strip diagrams are shown to give anomalies, implying that spurious longitudinal modes cannot be consistently decoupled. However, the anomalies cancel when the two diagrams are added together if the gauge group is chosen to be SO(32). In carrying out the analysis, two different regulators are considered, but the same conclusions emerge in both cases. The authors point out where various terms in the low-energy effective action originate in superstring diagrams

49

QED from six-dimensional vortex and gauge anomalies

Starting from an anomaly-free Abelian Higgs model coupled to gravity in a 6-dimensional space-time we construct an effective four-dimensional theory of charged fermions interacting with U(1) Abelian gauge field and gravity, both localised near the core of a Nielsen-Olesen vortex configuration. We show that an anomaly free theory in 6-dimensions can give rise to an anomalous theory in D=4, which suggests a possibility of consistent regularisation of abelian anomalous chiral gauge theories in four dimensions. We also show that the spectrum of charged bulk fermions has a mass gap.

Randjbar-Daemi, S; Randjbar-Daemi, Seif; Shaposhnikov, Mikhail

2003-01-01

50

A new anomaly-free gauged supergravity in six dimensions

Energy Technology Data Exchange (ETDEWEB)

We present a new anomaly-free gauged N = 1 supergravity model in six dimensions. The gauge group is E{sub 7} x G{sub 2} x U(1){sub R}, with all hyperinos transforming in the product representation (56,14). The theory admits monopole compactifications to R{sup 4} x S{sup 2}, leading to D = 4 effective theories with broken supersymmetry and massless fermions.

Avramis, Spyros D. [Department of Physics, National Technical University of Athens, GR-15773, Zografou, Athens (Greece); Kehagias, Alex [Department of Physics, National Technical University of Athens, GR-15773, Zografou, Athens (Greece); Randjbar-Daemi, Seif [International Center for Theoretical Physics, 34100, Trieste (Italy)

2005-05-01

51

Anomaly constraints in chiral gauge theories

International Nuclear Information System (INIS)

A general procedure for constructing solutions to 't Hooft's anomaly equations in left-right asymmetric theories is discussed. All the known solutions and a few new ones are obtained from a unified treatment. The characteristic feature is the appearance of a global symmetry which can be on ordinary group or a superalgebra. (orig.)

52

Global gauge anomalies in two-dimensional bosonic sigma models

We revisit the gauging of rigid symmetries in two-dimensional bosonic sigma models with a Wess-Zumino term in the action. Such a term is related to a background closed 3-form H on the target space. More exactly, the sigma-model Feynman amplitudes of classical fields are associated to a bundle gerbe with connection of curvature H over the target space. Under conditions that were unraveled more than twenty years ago, the classical amplitudes may be coupled to the topologically trivial gauge fields of the symmetry group in a way which assures infinitesimal gauge invariance. We show that the resulting gauged Wess-Zumino amplitudes may, nevertheless, exhibit global gauge anomalies that we fully classify. The general results are illustrated on the example of the WZW and the coset models of conformal field theory. The latter are shown to be inconsistent in the presence of global anomalies. We introduce a notion of equivariant gerbes that allow an anomaly-free coupling of the Wess-Zumino amplitudes to all gauge field...

Gawedzki, Krzysztof; Waldorf, Konrad

2010-01-01

53

Anomaly cancellation and conformality in quiver gauge theories

International Nuclear Information System (INIS)

Abelian quiver gauge theories provide non-supersymmetric candidates for the conformality approach to physics beyond the standard model. Written as N=0, U(N)n gauge theories, however, they have mixed U(1)pU(1)q2 and U(1)pSU(N)q2 triangle anomalies. It is shown how to construct explicitly a compensatory term ?Lcomp which restores gauge invariance of Leff=L+?Lcomp under U(N)n. It can lead to a negative contribution to the U(1)?-function and hence to one-loop conformality at high energy for all dimensionless couplings

54

Nature of local gravitational anomalies in northern Ustyurt

Energy Technology Data Exchange (ETDEWEB)

On the basis of analyzing numerous density determinations of sedimentary deposits in northern Ustyurt it was established that there is a regular increase in ore crust density with deposit depth in the absence of sharp jumps at the boundaries of separate layers. Local gravitational anomalies observed over anticlinal structures are explained by the effect of density changes of stratigraphic combinations, as shown in the literature. In this situation the correlation methods of interpreting gravity anomalies are the most effective.

Matusevich, A.V.; Shraibman, V.I.

1976-01-01

55

Algebraic characterization of gauge anomalies on a nontrivial bundle

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 derivative as a BRST commutator is extended to the present case.

John, P; Schweda, Manfred; Sorella, S P

1996-01-01

56

Algebraic characterization of gauge anomalies on a nontrivial bundle

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

57

Positivity constraints on anomalies in supersymmetric gauge theories

International Nuclear Information System (INIS)

The relation between the trace and R-current anomalies in supersymmetric theories implies that the U(1)RF2, U(1)R, and U(1)R3 anomalies which are matched in studies of N=1 Seiberg duality satisfy positivity constraints. Some constraints are rigorous and others conjectured as four-dimensional generalizations of the Zamolodchikov c theorem. These constraints are tested in a large number of N=1 supersymmetric gauge theories in the non-Abelian Coulomb phase, and they are satisfied in all renormalizable models with unique anomaly-free R current, including those with accidental symmetry. Most striking is the fact that the flow of the Euler anomaly coefficient aUV-aIR is always positive, as conjectured by Cardy. copyright 1998 The American Physical Society

58

Gerbes, M5-brane anomalies and E8 gauge theory

International Nuclear Information System (INIS)

Abelian gerbes and twisted bundles describe the topology of the NS 3-form gauge field strength H. We review how they have been usefully applied to study and resolve global anomalies in open string theory. Abelian 2-gerbes and twisted nonabelian gerbes describe the topology of the 4-form field strength G of M-theory. We show that twisted nonabelian gerbes are relevant in the study and resolution of global anomalies of multiple coinciding M5-branes. Global anomalies for one M5-brane have been studied by Witten and by Diaconescu, Freed and Moore. The structure and the differential geometry of twisted nonabelian gerbes (i.e. modules for 2-gerbes) is defined and studied. The nonabelian 2-form gauge potential living on multiple coinciding M5-branes arises as curving (curvature) of twisted nonabelian gerbes. The nonabelian group is in general ?-tildeE8, the central extension of the E8 loop group. The twist is in general necessary to cancel global anomalies due to the non-triviality of the 11-dimensional 4-form field strength G and due to the possible torsion present in the cycles the M5-branes wrap. Our description of M5-branes global anomalies leads to the D4-branes one upon compactification of M-theory to Type IIA theory. (author)

59

Muon g-2 Anomaly and Dark Leptonic Gauge Boson

One of the major motivations to search for a dark gauge boson of MeV-GeV scale is the long-standing muon g-2 anomaly. Because of active searches such as fixed target experiments and rare meson decays, the muon g-2 favored parameter region has been rapidly reduced. With the most recent data, it is practically excluded now in the popular dark photon model. We overview the issue and investigate a potentially alternative model based on the gauged lepton number or U(1)_L, which is under different experimental constraints.

Lee, Hye-Sung

2014-01-01

60

Functorial QFT, gauge anomalies and the Dirac determinant bundle

Energy Technology Data Exchange (ETDEWEB)

Using properties of the determinant line bundle for a family of elliptic boundary value problems, we explain how the Fock space functor defines an axiomatic quantum field theory which formally models the Fermionic path integral. The ''sewing axiom'' of the theory arises as an algebraic pasting law for the determinant of the Dirac operator. We show how representations of the boundary gauge group fit into this description and that this leads to a Fock functor description of certain gauge anomalies. (orig.)

Mickelsson, J. [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Theoretical Physics; Scott, S. [Dept. of Mathematics, King' s College, London (United Kingdom)

2001-06-01

61

Muon g-2 Anomaly and Dark Leptonic Gauge Boson

Energy Technology Data Exchange (ETDEWEB)

One of the major motivations to search for a dark gauge boson of MeV-GeV scale is the long-standing muon g-2 anomaly. Because of active searches such as fixed target experiments and rare meson decays, the muon g-2 favored parameter region has been rapidly reduced. With the most recent data, it is practically excluded now in the popular dark photon model. We overview the issue and investigate a potentially alternative model based on the gauged lepton number or U(1)_L, which is under different experimental constraints.

Lee, Hye-Sung [W& M

2014-11-01

62

Gravitation, gauge theories and differential geometry

International Nuclear Information System (INIS)

The purpose of this article is to outline various mathematical ideas, methods, and results, primarily from differential geometry and topology, and to show where they can be applied to Yang-Mills gauge theories and Einstein's theory of gravitation.We have several goals in mind. The first is to convey to physicists the bases for many mathematical concepts by using intuitive arguments while avoiding the detailed formality of most textbooks. Although a variety of mathematical theorems will be stated, we will generally give simple examples motivating the results instead of presenting abstract proofs. Another goal is to list a wide variety of mathematical terminology and results in a format which allows easy reference. The reader then has the option of supplementing the descriptions given here by consulting standard mathematical references and articles such as those listed in the bibliography. Finally, we intend this article to serve the dual purpose of acquainting mathematicians with some basic physical concepts which have mathematical ramifications; physical problems have often stimuladed new directions in mathematical thought. (orig./WL)

63

Spherically-symmetric gravitational fields in the metric-affine gauge theory of gravitation

Geometric structure of spherically-symmetric space-time in metric-affine gauge theory of gravity is studied. Restrictions on curvature tensor and Bianchi identities are obtained. By using certain simple gravitational Lagrangian the solution of gravitational equations for vacuum spherically-symmetric gravitational field is obtained.

Minkevich, A V; Vasilevski, Yu. G.

2003-01-01

64

Could the Pioneer anomaly have a gravitational origin?

If the Pioneer anomaly has a gravitational origin, it would, according to the equivalence principle, distort the motions of the planets in the Solar System. Since no anomalous motion of the planets has been detected, it is generally believed that the Pioneer anomaly can not originate from a gravitational source in the Solar System. However, this conclusion becomes less obvious when considering models that either imply modifications to gravity over long distances or gravitational sources localized to the outer Solar System, given the uncertainty in the orbital parameters of the outer planets. Following the general assumption that the Pioneer spacecraft move geodesically in a spherically symmetric space-time metric, we derive the metric disturbance that is needed in order to account for the Pioneer anomaly. We then analyze the residual effects on the astronomical observables of the three outer planets that would arise from this metric disturbance, given an arbitrary metric theory of gravity. Providing a method for comparing the computed residuals with actual residuals, our results imply that the presence of a perturbation to the gravitational field necessary to induce the Pioneer anomaly is in conflict with available data for the planets Uranus and Pluto, but not for Neptune. We therefore conclude that the motion of the Pioneer spacecraft must be nongeodesic. Since our results are model-independent within the class of metric theories of gravity, they can be applied to rule out any model of the Pioneer anomaly that implies that the Pioneer spacecraft move geodesically in a perturbed space-time metric, regardless of the origin of this metric disturbance.

Tangen, Kjell

2007-08-01

65

Non-Singular Cosmology and Gauge Theories of Gravitation

Digital Repository Infrastructure Vision for European Research (DRIVER)

The resolution of the problem of cosmological singularity in the framework of gauge theories of gravitation is discussed. Generalized cosmological Friedmann equations for homogeneous isotropic models filled by interacting scalar fields and usual gravitating matter are deduced. It is shown that generic feature of cosmological models of flat, open and closed type is their regular bouncing character.

Minkevich, Albert V.

2004-01-01

66

On the gravitational origin of the Pioneer Anomaly

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

67

Gauge Invariant Effective Stress-Energy Tensors for Gravitational Waves

It is shown that if a generalized definition of gauge invariance is used, gauge invariant effective stress-energy tensors for gravitational waves and other gravitational perturbations can be defined in a much larger variety of circumstances than has previously been possible. In particular it is no longer necessary to average the stress-energy tensor over a region of spacetime which is larger in scale than the wavelengths of the waves and it is no longer necessary to restrict attention to high frequency gravitational waves.

Anderson, P R

1997-01-01

68

Notes on gauge theory and gravitation

International Nuclear Information System (INIS)

In order to investigate whether Einstein's general relativity theory (GRT) fits into the general scheme of a gauge theory, first the concept of a (classical) gauge theory is outlined in an introductionary spacetime approach. Having thus fixed the notation and the main properties of gauge fields, GRT is examined to find out what the gauge potentials and the corresponding gauge group might be. In this way the possibility of interpreting GRT as a gauge theory of the 4-dimensional translation group T(4) = (R4, +), and where the gauge potentials are incorporated in a T(4)-invariant way via orthonormal anholonomic basis 1-forms is considered. To include also the spin aspect a natural extension of GRT is given by gauging also the Lorentz group, whereby a Riemann-Cartan spacetime (U4-spacetime) comes into play. (Auth.)

69

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

70

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.)

71

NS5-branes in IIA supergravity and gravitational anomalies

We construct a gravitational-anomaly-free effective action for the coupled system of IIA D=10 dynamical supergravity interacting with an NS5-brane. The NS5-brane is considered as elementary in that the associated current is a delta-function supported on its worldvolume. Our approach is based on a Chern-kernel which encodes the singularities of the three-form field strength near the brane in an SO(4)-invariant way and provides a solution for its Bianchi identity in terms of a two-form potential. A dimensional reduction of the recently constructed anomaly-free effective action for an elementary M5-brane in D=11 is seen to reproduce our ten-dimensional action. The Chern-kernel approach provides in particular a concrete realization of the anomaly cancellation mechanism envisaged by Witten.

Cariglia, M; Cariglia, Marco; Lechner, Kurt

2002-01-01

72

Anomaly-free formulation of chiral gauge theory and quantum holonomy

International Nuclear Information System (INIS)

We investigate the quantization of a fermion field coupled to external gauge fields. Defining the S-matrix carefully by means of the time-dependent Bogoliubov transformation, we show a possibility of an anomaly-free formulation of chiral gauge theories. In this formulation the gauge anomaly is canceled by the non-trivial quantum holonomy of the fermionic Fock vacuum. (author)

73

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

74

Holomorphic Anomaly in Gauge Theory on ALE space

We consider four-dimensional Omega-deformed N=2 supersymmetric SU(2) gauge theory on A1 space and its lift to five dimensions. We find that the partition functions can be reproduced via special geometry and the holomorphic anomaly equation. Schwinger type integral expressions for the boundary conditions at the monopole/dyon point in moduli space are inferred. The interpretation of the five-dimensional partition function as the partition function of a refined topological string on A1x(local P1xP1) is suggested.

Krefl, Daniel

2011-01-01

75

Holomorphic Anomaly in Gauge Theory on ALE space

We consider four-dimensional ?-deformed {{N} = 2} supersymmetric SU(2) gauge theory on A 1 space and its lift to five dimensions. We find that the partition functions can be reproduced via special geometry and the holomorphic anomaly equation. Schwinger-type integral expressions for the boundary conditions at the monopole/dyon point in moduli space are inferred. The interpretation of the five-dimensional partition function as the partition function of a refined topological string on A 1 × (local {{P}1 × {P}^1}) is suggested.

Krefl, Daniel; Shih, Sheng-Yu Darren

2013-08-01

76

Gauge field, strings, solitons, anomalies and the speed of life

It's been said that "mathematics is biology's next microscope, only better; biology is mathematics' next physics, only better". Here we aim for something even better. We try to combine mathematical physics and biology into a picoscope of life. For this we merge techniques which have been introduced and developed in modern mathematical physics, largely by Ludvig Faddeev to describe objects such as solitons and Higgs and to explain phenomena such as anomalies in gauge fields. We propose a synthesis that can help to resolve the protein folding problem, one of the most important conundrums in all of science. We apply the concept of gauge invariance to scrutinize the extrinsic geometry of strings in three dimensional space. We evoke general principles of symmetry in combination with Wilsonian universality and derive an essentially unique Landau-Ginzburg energy that describes the dynamics of a generic string-like configuration in the far infrared. We observe that the energy supports topological solitons, that perta...

Niemi, Antti J

2014-01-01

77

Hydrodynamics with gauge anomaly: Variational principle and Hamiltonian formulation

We present a variational principle for relativistic hydrodynamics with gauge-anomaly terms for a fluid coupled to an Abelian background gauge field. For this we utilize the Clebsch parametrization of the velocity field. We also set up the Hamiltonian formulation and the canonical framework for the theory. While the equations of motion only involve the density and velocity fields, i.e., the Clebsch potentials only appear in the combination which is the velocity field, the generators of symmetry transformations (including the Hamiltonian) depend explicitly on one of the Clebsch potentials, if the background field is time-dependent. For the special case of time-independent background fields, this feature is absent.

Monteiro, Gustavo M; Nair, V P

2014-01-01

78

Gauge and Averaging in Gravitational Self-force

A difficulty with previous treatments of the gravitational self-force is that an explicit formula for the force is available only in a particular gauge (Lorenz gauge), where the force in other gauges must be found through a transformation law. For a class of gauges satisfying a "parity condition" ensuring that the Hamiltonian center of mass of the particle is well-defined, I show that the gravitational self-force is always given by the angle-average of the bare gravitational force. To derive this result I replace the computational strategy of previous work with a new approach, wherein the form of the force is first fixed up to a gauge-invariant piece by simple manipulations, and then that piece is determined by working in a gauge designed specifically to simplify the computation. This offers significant computational savings over the Lorenz gauge, since the Hadamard expansion is avoided entirely and the metric perturbation takes a very simple form. I also show that the rest mass of the particle does not evolv...

Gralla, Samuel E

2011-01-01

79

On the gravitational waves on the background of anomaly-induced inflation

International Nuclear Information System (INIS)

In the very early Universe matter can be described as a conformal invariant ultra-relativistic perfect fluid, which does not contribute, on classical level, to the evolution of the isotropic and homogeneous metric. However, in this situation the vacuum effects of quantum matter fields become important. The vacuum effective action depends, essentially, on the particle content of the underlying gauge model. If we suppose that there is some desert in the particle spectrum, just below the Planck mass, then the effect of conformal trace anomaly is dominating at the corresponding energies. With some additional constraints on the gauge model (which favor extended or supersymmetric versions of the Standard Model rather than the minimal one), one arrives at the stable inflation. In this article we report about the calculation of the gravitational waves in this model. The result for the perturbation spectrum is close to the one for the conventional inflaton model, and is in agreement with the existing Cobe data

80

Trace anomaly, massless scalars, and the gravitational coupling of QCD

The anomalous effective action describing the coupling of gravity to a non-Abelian gauge theory can be determined by a variational solution of the anomaly equation, as shown by Riegert long ago. It is given by a nonlocal expression, with the nonlocal interaction determined by the Green’s function of a conformally covariant operator of fourth order. In recent works it has been shown that this interaction is mediated by a simple pole in an expansion around a Minkowski background, coupled in the infrared in the massless fermion limit. This result relies on the local formulation of the original action in terms of two auxiliary fields, one physical scalar and one ghost, which take the role of massless composite degrees of freedom. In the gravity case, the two scalars have provided ground in favor of some recent proposals of an infrared approach to the solution of the dark energy problem, entirely based on the behavior of the vacuum energy at the QCD phase transition. As a test of this general result, we perform a complete one-loop computation of the effective action describing the coupling of a non-Abelian gauge theory to gravity. We confirm the appearance of an anomaly pole which contributes to the trace part of the TJJ correlator and of extra poles in its trace-free part, in the quark and gluon sectors, describing the coupling of the energy-momentum tensor (T) to two non-Abelian gauge currents (J).

Armillis, Roberta; Corianò, Claudio; Delle Rose, Luigi

2010-09-01

81

Branes as solutions of gauge theories in gravitational field

International Nuclear Information System (INIS)

The idea of the Gauss map is unified with the concept of branes as hypersurfaces embedded into D-dimensional Minkowski space. The map introduces new generalized coordinates of branes alternative to their world vectors x and identified with the gauge and other massless fields. In these coordinates the Dirac p-branes realize extremals of the Euler-Lagrange equations of motion of a (p + 1)- dimensional SO(D-p-1) gauge-invariant action in a gravitational background. (orig.)

82

Gravitating SO (3,1) gauge field

Energy Technology Data Exchange (ETDEWEB)

In this article, we postulate SO (3,1) as a local symmetry of any relativistic theory. This is equivalent to assuming the existence of a gauge field associated with this noncompact group. This SO (3,1) gauge field is the spinorial affinity which usually appears when we deal with weighting spinors, which, as is well known, cannot be coupled to the metric tensor field. Furthermore, according to the integral approach to gauge fields proposed by Yang, it is also recognized that in order to obtain models of gravity we have to introduce ordinary affinities as the gauge field associated with GL (4) (the local symmetry determined by the parallel transport). Thus if we assume both GL (4) and SO (3,1) as local independent symmetries we are led to analyze the dynamical gauge system constituted by the Einstein field interacting with the SO (3,1) Weyl--Yang gauge field. We think this system is a possible model of strong gravity. Once we give the first-order action for this Einstein--Weyl--Yang system we study whether the SO (3,1) gauge field could have a tetrad associated with it. It is also shown that both fields propagate along a unique characteristic cone. Algebraic and differential constraints are solved when the system evolves along a null coordinate. The unconstrained expression for the action of the system is found working in the Bondi gauge. That allows us to exhibit an explicit expression of the dynamical generator of the system. Its signature turns out to be nondefinite, due to the nondefinite contribution of the Weyl--Yang field, which has the typical spinorial behavior. A conjecture is made that such an unpleasant feature could be overcome in the quantized version of this model.

Aragone, C.; Restuccia, A.

1978-08-01

83

Covariant and consistent anomalies in even-dimensional chiral gauge theories

International Nuclear Information System (INIS)

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. (orig.)

84

On the Interpretation of Gravitational Corrections to Gauge Couplings

Several recent papers discuss gravitational corrections to gauge couplings that depend quadratically on the energy. In the framework of the background-field approach, these correspond in general to adding to the effective action terms quadratic in the field strength but with higher-order space-time derivatives. We observe that such terms can be removed by appropriate local field redefinitions, and do not contribute to physical scattering-matrix elements. We illustrate this observation in the context of open string theory, where the effective action includes, among other terms, the well-known Born-Infeld form of non-linear electrodynamics. We conclude that the quadratically energy-dependent gravitational corrections are \\emph{not} physical in the sense of contributing to the running of a physically-measurable gauge coupling, or of unifying couplings as in string theory.

Ellis, John

2012-01-01

85

A particle-picture approach to anomalies in chiral gauge theories

International Nuclear Information System (INIS)

The system of a chiral fermion field coupled to a background gauge field is considered. By taking what we call the particle picture and carefully defining the S-matrix in the Heisenberg picture, we investigate anomalous phenomena in this system. It is shown by explicit calculations that the gauge-field configuration with nonvanishing topological-charge causes anomalous production of particles that is directly responsible for the chiral U(1) anomaly. Unlike the chiral U(1) anomaly, the gauge anomaly, that is, gauge non-invariance of the S-matrix is a problem that arises in the phase of the S-matrix. It is shown that this phase is related to the freedom existing in the quantization method, and that a suitably chosen phase which of course is consistent with the equation of motion can remove the gauge anomaly. Finally, a modified form of path-integral quantization for this system is proposed. (orig.)

86

Trace Anomaly, Massless Scalars and the Gravitational Coupling of QCD

The anomalous effective action describing the coupling of gravity to a non-abelian gauge theory can be determined by a variational solution of the anomaly equation, as shown by Riegert long ago. It is given by a nonlocal expression, with the non-local interaction determined by the Green's function of a conformally covariant operator of fourth order. In recent works it has been shown that this interaction is mediated by a simple pole in an expansion around a Minkowski background. This result relies on the local formulation of the original action in terms of two auxiliary fields, one physical scalar and one ghost, which take the role of massless composite degrees of freedom. In the gravity case, the two scalars have provided ground in favour of some recent proposals of an infrared approach to the solution of the dark energy problem, entirely based on the behaviour of the vacuum energy at the QCD phase transition. For this purpose, we derive the effective action describing the coupling of a non-abelian gauge the...

Armillis, Roberta; Rose, Luigi Delle

2010-01-01

87

Physical decomposition of the gauge and gravitational fields

International Nuclear Information System (INIS)

Physical decomposition of the non-Abelian gauge field has recently helped to achieve a meaningful gluon spin. Here we extend this approach to gravity and attempt a meaningful gravitational energy. The metric is unambiguously separated into a pure geometric term which contributes a null curvature tensor, and a physical term which represents the true gravitational effect and always vanishes in a flat space-time. By this decomposition the conventional pseudotensors of the gravitational stress-energy are easily rescued to produce a definite physical result. Our decomposition applies to any symmetric tensor, and has an interesting relation to the transverse-traceless decomposition discussed by Arnowitt, Deser and Misner, and by York.

88

Anomaly-free gauges in superstring theory and double supersymmetric sigma-model

International Nuclear Information System (INIS)

Superharmonic gauge which is a nontrivial analog of the harmonic gauge in bosonic string theory is constructed for the fermionic superstrings. In contrast to the conformal gauge, the harmonic gauge in bosonic string and superharmonic gauge in superstring theory are shown to be free from previously discovered BRST anomaly (in critical dimension) in higher orders of string perturbation theory and thus provide the setup for consistent quantization of (super)string theory. Superharmonic gauge appears to be closely connected with the supersymmetric ?-model with the target space being also a supermanifold. 28 refs

89

Resolution of axial anomaly problem in supersymmetric gauge theories

International Nuclear Information System (INIS)

The explicit form of transformation is found which converters the operators, involved in axial anomaly, from the renormalization scheme obeying the Adler-BaAdeen theorem to a supersymmetric one. It is shown that there is no contradiction between axial current and superconformal anomalies. In supersymmetric scheme the axial current and its anomaly belong to the corresponding supermultiplets

90

Gravitational self-force from radiation-gauge metric perturbations

Calculations of the gravitational self-force (GSF) on a point mass in curved spacetime require as input the metric perturbation in a sufficiently regular gauge. A basic challenge in the program to compute the GSF for orbits around a Kerr black hole is that the standard procedure for reconstructing the metric perturbation is formulated in a class of “radiation” gauges, in which the particle singularity is nonisotropic and extends away from the particle’s location. Here we present two practical schemes for calculating the GSF using a radiation-gauge reconstructed metric as input. The schemes are based on a detailed analysis of the local structure of the particle singularity in the radiation gauges. We show that three types of radiation gauge exist: two containing a radial stringlike singularity emanating from the particle, either in one direction (“half-string” gauges) or both directions (“full-string” gauges); and a third type containing no strings but with a jump discontinuity (and possibly a delta function) across a surface intersecting the particle. Based on a flat-space example, we argue that the standard mode-by-mode reconstruction procedure yields the “regular half” of a half-string solution, or (equivalently) either of the regular halves of a no-string solution. For the half-string case, we formulate the GSF in a locally deformed radiation gauge that removes the string singularity near the particle. We derive a mode-sum formula for the GSF in this gauge, which is analogous to the standard Lorenz-gauge formula but requires a correction to the values of the regularization parameters. For the no-string case, we formulate the GSF directly, without a local deformation, and we derive a mode-sum formula that requires no correction to the regularization parameters but involves a certain averaging procedure. We explain the consistency of our results with Gralla’s invariance theorem for the regularization parameters, and we discuss the correspondence between our method and a related approach by Friedman et al.

Pound, Adam; Merlin, Cesar; Barack, Leor

2014-01-01

91

Gravitational self-force in a radiation gauge

In this, the first of two companion papers, we present a method for finding the gravitational self-force in a modified radiation gauge for a particle moving on a geodesic in a Schwarzschild or Kerr spacetime. An extension of an earlier result by Wald is used to show the spin weight ±2 perturbed Weyl scalar (?0 or ?4) determines the metric perturbation outside the particle up to a gauge transformation and an infinitesimal change in mass and angular momentum. A Hertz potential is used to construct the part of the retarded metric perturbation that involves no change in mass or angular momentum from ?0 in a radiation gauge. The metric perturbation is completed by adding changes in the mass and angular momentum of the background spacetime outside the radial coordinate r0 of the particle in any convenient gauge. The resulting metric perturbation is singular only on the trajectory of the particle. A mode-sum method is then used to renormalize the self-force. Gralla shows that the renormalized self-force can be used to find the correction to a geodesic orbit in a gauge for which the leading, O(?-1), term in the metric perturbation has spatial components even under a parity transformation orthogonal to the particle trajectory, and we verify that the metric perturbation in a radiation gauge satisfies that condition. We show that the singular behavior of the metric perturbation and the expression for the bare self-force have the same power-law behavior in L=?+1/2 as in a Lorenz gauge (with different coefficients). We explicitly compute the singular Weyl scalar and its mode-sum decomposition to subleading order in L for a particle in circular orbit in a Schwarzschild geometry and obtain the renormalized field. Because the singular field can be defined as this mode sum, the coefficients of each angular harmonic in the sum must agree with the large L limit of the corresponding coefficients of the retarded field. One may therefore compute the singular field by numerically matching the retarded field to a power series in L. To check the accuracy of the numerical method, we analytically compute leading and subleading terms in the singular expansion of ?0 and compare the numerical and analytic values of the renormalization constants, finding agreement to high precision. Details of the numerical computation of the perturbed metric, the self-force, and the quantity h??u?u? (gauge invariant under helically symmetric gauge transformations) are presented for this test case in the companion paper.

Keidl, Tobias S.; Shah, Abhay G.; Friedman, John L.; Kim, Dong-Hoon; Price, Larry R.

2010-12-01

92

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

International Nuclear Information System (INIS)

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, -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

93

Weyl and Ghost Number Anomalies in the POLYAKOV’S Light-Cone Gauge

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, -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, Hiroshi

94

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

95

We perform an explicit one-loop calculation for the gravitational contributions to the two-, three- and four-point gauge Green's functions with paying attention to the quadratic divergences. It is shown for the first time in the diagrammatic calculation that the Slavnov-Taylor identities are preserved even if the quantum graviton effects are included at one-loop level, such a conclusion is independent of the choice of regularization schemes. We also present a regularization scheme independent calculation based on the gauge condition independent background field framework of Vilkovisky-DeWitt's effective action with focusing on both the quadratic divergence and quartic divergence that is not discussed before. With the harmonic gauge condition, the results computed by using the traditional background field method can consistently be recovered from the Vilkovisky-DeWitt's effective action approach by simply taking a limiting case, and are found to be the same as the ones yielded by the diagrammatic calculation. ...

Tang, Yong

2011-01-01

96

Electric/magnetic duality for chiral gauge theories with anomaly cancellation

International Nuclear Information System (INIS)

We show that 4D gauge theories with Green-Schwarz anomaly cancellation and possible generalized Chern-Simons terms admit a formulation that is manifestly covariant with respect to electric/magnetic duality transformations. This generalizes previous work on the symplectically covariant formulation of anomaly-free gauge theories as they typically occur in extended supergravity, and now also includes general theories with (pseudo-)anomalous gauge interactions as they may occur in global or local N = 1 supersymmetry. This generalization is achieved by relaxing the linear constraint on the embedding tensor so as to allow for a symmetric 3-tensor related to electric and/or magnetic quantum anomalies in these theories. Apart from electric and magnetic gauge fields, the resulting Lagrangians also feature two-form fields and can accommodate various unusual duality frames as they often appear, e.g., in string compactifications with background fluxes.

97

We develop a general method to compute correlation functions of fractional quantum Hall (FQH) states on a curved space. In a curved space, local transformation properties of FQH states are examined through local geometric variations, which are essentially governed by the gravitational anomaly. Furthermore, we show that the electromagnetic response of FQH states is related to the gravitational response (a response to curvature). Thus, the gravitational anomaly is also seen in the structure factor and the Hall conductance in flat space. The method is based on an iteration of a Ward identity obtained for FQH states. PMID:25105643

Can, T; Laskin, M; Wiegmann, P

2014-07-25

98

On gravitational dressing of 2D field theories in chiral gauge

After giving a pedagogical review of the chiral gauge approach to 2D gravity, with particular emphasis on the derivation of the gravitational Ward identities, we discuss in some detail the interpretation of matter correlation functions coupled to gravity in chiral gauge. We argue that in chiral gauge no {\\it explicit} gravitational dressing factor, analogue to the Liouville exponential in conformal gauge, is necessary for left-right symmetric matter operators. In particular, we examine the gravitationally dressed four-point correlation function of products of left and right fermions. We solve the corresponding gravitational Ward identity exactly: in the presence of gravity this four-point function exhibits a logarithmic short-distance singularity, instead of the power-law singularity in the absence of gravity. This rather surprising effect is non-perturbative in the gravitational coupling and is a sign for logarithms in the gravitationally dressed operator product expansions. We also discuss some perturbative...

Bilal, Adel; Bilal, Adel; Kogan, I

1995-01-01

99

Chiral anomalies in higher-derivative supersymmetric 6D gauge theories

Energy Technology Data Exchange (ETDEWEB)

We show that the recently constructed higher-derivative 6D SYM theory involves internal chiral anomaly breaking gauge invariance. The anomaly is cancelled when adding to the theory an adjoint matter hyper-multiplet. One shows that as the effective charge grows at high energies, the theories are not consistently defined nonperturbatively. Constructing a nontrivial 6D theory that would be internally consistent both perturbatively and nonperturbatively remains a major challenge. (author)

Smilga, A.V. [SUBATECH, Universite de Nantes, 4 rue Alfred Kastler, BP 20722, Nantes 44307 (France)

2006-08-15

100

Chiral anomalies in higher-derivative supersymmetric 6D gauge theories

International Nuclear Information System (INIS)

We show that the recently constructed higher-derivative 6D SYM theory involves internal chiral anomaly breaking gauge invariance. The anomaly is cancelled when adding to the theory an adjoint matter hyper-multiplet. One shows that as the effective charge grows at high energies, the theories are not consistently defined nonperturbatively. Constructing a nontrivial 6D theory that would be internally consistent both perturbatively and nonperturbatively remains a major challenge. (author)

101

Non-commutative differential calculus and the axial anomaly in Abelian lattice gauge theories

International Nuclear Information System (INIS)

The axial anomaly in lattice gauge theories has a topological nature when the Dirac operator satisfies the Ginsparg-Wilson relation. We study the axial anomaly in Abelian gauge theories on an infinite hypercubic lattice by utilizing cohomological arguments. The crucial tool in our approach is the non-commutative differential calculus (NCDC) which makes the Leibniz rule of exterior derivatives valid on the lattice. The topological nature of the 'Chern character' on the lattice becomes manifest in the context of NCDC. Our result provides an algebraic proof of Luescher's theorem for a four-dimensional lattice and its generalization to arbitrary dimensions

102

Could the Pioneer anomaly have a gravitational origin?

International Nuclear Information System (INIS)

ories of gravity, they can be applied to rule out any model of the Pioneer anomaly that implies that the Pioneer spacecraft move geodesically in a perturbed space-time metric, regardless of the origin of this metric disturbance

103

Anomaly cancellation in a class of chiral flavor gauge models

International Nuclear Information System (INIS)

We show typical features on anomaly cancellation in the 3 - n - 1 extensions of the 3 - 2 - 1 standard model, with n = 3,4 which has been proposed recently. We point out that in this class of theories a natural explanation for the fundamental question of fermion family replication arises from the theoretical requirements of renormalizability and self-consistency, which constrains the number of the QFD families to the QCD color degrees of freedom. (author). 10 refs

104

Anomaly cancellation in a class of chiral flavor gauge models

International Nuclear Information System (INIS)

Typical features on anomaly cancellation in the 3-n-1 extensions of the 3-2-1 standard model, with n=3,4, which has been proposed recently, are shown. It is pointed out that in this class of theories a natural explanation for the fundamental question of fermion family replication arises from the theoretical requirements of renormalizability and self-consistency, which constrains the number of the QFD families to the QCD color degrees of freedom. (author). 10 refs

105

Functorial QFT, Gauge Anomalies and the Dirac Determinant Bundle

Digital Repository Infrastructure Vision for European Research (DRIVER)

Using properties of the determinant line bundle for a family of elliptic boundary value problems, we explain how the Fock space functor defines an axiomatic quantum field theory which formally models the Fermionic path integral. The 'sewing axiom' of the theory arises as an algebraic pasting law for the determinant of the Dirac operator. We show how representations of the boundary gauge group fit into this description and that this leads to a Fock functor description of cert...

Mickelsson, Jouko; Scott, Simon

1999-01-01

106

Pioneer anomaly? Gravitational pull due to the Kuiper belt

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

107

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

2013-08-01

108

Gravitational solution to the Pioneer 10/11 anomaly

International Nuclear Information System (INIS)

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 ? and the mass of the skew-symmetric field ? = 1/?. 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

109

Gravitational solution to the Pioneer 10/11 anomaly

Energy Technology Data Exchange (ETDEWEB)

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; Moffat, J W [Perimeter Institute for Theoretical Physics, Waterloo, ON N2L 2Y5 (Canada); Department of Physics, University of Waterloo, Waterloo, ON N2L 3G1 (Canada)

2006-05-21

110

Problem of Cosmological Singularity, Inflationary Cosmology and Gauge Theories of Gravitation

Digital Repository Infrastructure Vision for European Research (DRIVER)

Problem of cosmological singularity is discussed in the framework of gauge theories of gravitation. Generalizing cosmological Friedmann equations (GCFE) for homogeneous isotropic models including scalar fields and usual gravitating matter are introduced. It is shown that by certain restrictions on equation of state of gravitating matter and indefinite parameter of GCFE generic feature of inflationary cosmological models of flat, open and closed type is their regular bouncing...

Minkevich, A. V.

2003-01-01

111

Indefiniteness of the Conformal Anomaly of the String Theory in the Harmonic Gauge

The derivation of the critical dimensions D=26 of the bosonic string theory based on the two-dimensional quantum gravity in the harmonic gauge is criticized. The conformal anomaly calculated in lowest-order approximation crucially depends on the presence of a certain part of the FP-ghost Lagrangian density. However, this part can be eliminated by field redefinition and, moreover, reduces to a total divergence in lowest-order approximation. Thus the assertion that the anomaly is proportional to (D-26) is groundless.

Abe, Mitsuo; Nakanishi, Noboru

112

Indefiniteness of the conformal anomaly of the string theory in the harmonic gauge

International Nuclear Information System (INIS)

In this paper, the derivation of the critical dimensions D = 26 of the bosonic string theory based on the two-dimensional quantum gravity in the harmonic gauge is criticized. The conformal anomaly calculated in lowest-order approximation crucially depends on the presence of a certain part of the FP-ghost Lagrangian density. However, this part can be eliminated by field redefinition and, moreover, reduces to a total divergence in lowest-order approximation. Thus, the assertion that the anomaly is proportional to (D - 26) is groundless

113

Gauge-invariant definition of gravitational radiation in Robertson-Walker cosmologies

International Nuclear Information System (INIS)

Gauge-invariant quantities are introduced which relate directly to the ideal fluid perturbations in Robertson-Walker backgrounds. It is shown how the vanishing of these gauge invariants is equivalent to the definition of purely radiative perturbations found in some early works. If one imposes a regularity condition, then the vanishing of just four gauge invariants is sufficient to define the condition of no perturbation of matter. The latter result is used to clarify the relationship to Hawking's definition of gravitational radiation

114

Decaying Hidden Gauge Boson and the PAMELA and ATIC/PPB-BETS Anomalies

We show that the PAMELA anomaly in the positron fraction as well as the ATIC/PPB-BETS excesses in the e^- + e^+ flux are simultaneously explained in our scenario that a hidden U(1)H gauge boson constitutes dark matter of the Universe and decays into the standard-model particles through a kinetic mixing with an U(1)B-L gauge boson. Interestingly, the B-L charge assignment suppresses an antiproton flux in consistent with the PAMELA and BESS experiments, while the hierarchy between the B-L symmetry breaking scale and the weak scale naturally leads to the right lifetime of O(10^26) seconds.

Chen, Chuan-Ren; Yanagida, T T

2008-01-01

115

Gauge/Anomaly Syzygy and Generalized Brane World Models of Supersymmetry Breaking

In theories in which SUSY is broken on a brane separated from the MSSM matter fields, supersymmetry breaking is naturally mediated in a variety of ways. Absent other light fields in the theory, gravity will mediate supersymmetry breaking through the conformal anomaly. If gauge fields propagate in the extra dimension they, too, can mediate supersymmetry breaking effects. The presence of gauge fields in the bulk motivates us to consider the effects of new messenger fields with holomorphic and non-holomorphic couplings to the supersymmetry breaking sector. These can lead to contributions to the soft masses of MSSM fields which dramatically alter the features of brane world scenarios of supersymmetry breaking. In particular, they can solve the negative slepton mass squared problem of anomaly mediation and change the predictions of gaugino mediation.

Nelson, A E; Nelson, Ann E.; Weiner, Neal

2002-01-01

116

Gravitational anomalies signaling the breakdown of classical gravity

Recent observations for three types of astrophysical systems severely challenge the GR plus dark matter scenario, showing a phenomenology which is what modified gravity theories predict. Stellar kinematics in the outskirts of globular clusters show the appearance of MOND type dynamics on crossing the $a_{0}$ threshold. Analysis shows a ``Tully-Fisher'' relation in these systems, a scaling of dispersion velocities with the fourth root of their masses. Secondly, an anomaly has been found at the unexpected scales of wide binaries in the solar neighbourhood. Binary orbital velocities cease to fall along Keplerian expectations, and settle at a constant value, exactly on crossing the $a_{0}$ threshold. Finally, the inferred infall velocity of the bullet cluster is inconsistent with the standard cosmological scenario, where much smaller limit encounter velocities appear. This stems from the escape velocity limit present in standard gravity; the ``bullet'' should not hit the ``target'' at more than the escape velocit...

Hernandez, X; Allen, C

2014-01-01

117

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

International Nuclear Information System (INIS)

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. (orig.)

118

Chiral rings, anomalies and loop equations in N = 1* gauge theories

International Nuclear Information System (INIS)

We examine the equivalence between the Konishi anomaly equations and the matrix model loop equations in N = 1* gauge theories, the mass deformation of N = 4 supersymmetric Yang-Mills. We perform the superfunctional integral of two adjoint chiral superfields to obtain an effective N = 1 theory of the third adjoint chiral superfield. By choosing an appropriate holomorphic variation, the Konishi anomaly equations correctly reproduce the loop equations in the corresponding three-matrix model. We write down the field theory loop equations explicitly by using a noncommutative product of resolvents peculiar to N = 1* theories. The field theory resolvents are identified with those in the matrix model in the same manner as for the generic N = 1 gauge theories. We cover all the classical gauge groups. In SO/Sp cases, both the one-loop holomorphic potential and the Konishi anomaly term involve twisting of index loops to change a one-loop oriented diagram to an unoriented diagram. The field theory loop equations for these cases show certain inhomogeneous terms suggesting the matrix model loop equations for the RP2 resolvent. (author)

119

Chiral rings, anomalies and loop equations in N=1* gauge theories

We examine the equivalence between the Konishi anomaly equations and the matrix model loop equations in N=1* gauge theories, the mass deformation of N=4 supersymmetric Yang-Mills. We perform the superfunctional integral of two adjoint chiral superfields to obtain an effective N=1 theory of the third adjoint chiral superfield. By choosing an appropriate holomorphic variation, the Konishi anomaly equations correctly reproduce the loop equations in the corresponding three-matrix model. We write down the field theory loop equations explicitly by using a noncommutative product of resolvents peculiar to N=1* theories. The field theory resolvents are identified with those in the matrix model in the same manner as for the generic N=1 gauge theories. We cover all the classical gauge groups. In SO/Sp cases, both the one-loop holomorphic potential and the Konishi anomaly term involve twisting of index loops to change a one-loop oriented diagram to an unoriented diagram. The field theory loop equations for these cases sh...

Itoh, T

2003-01-01

120

Chiral rings, anomalies and loop equations in N = 1* gauge theories

Energy Technology Data Exchange (ETDEWEB)

We examine the equivalence between the Konishi anomaly equations and the matrix model loop equations in N = 1* gauge theories, the mass deformation of N = 4 supersymmetric Yang-Mills. We perform the superfunctional integral of two adjoint chiral superfields to obtain an effective N = 1 theory of the third adjoint chiral superfield. By choosing an appropriate holomorphic variation, the Konishi anomaly equations correctly reproduce the loop equations in the corresponding three-matrix model. We write down the field theory loop equations explicitly by using a noncommutative product of resolvents peculiar to N = 1* theories. The field theory resolvents are identified with those in the matrix model in the same manner as for the generic N = 1 gauge theories. We cover all the classical gauge groups. In SO/Sp cases, both the one-loop holomorphic potential and the Konishi anomaly term involve twisting of index loops to change a one-loop oriented diagram to an unoriented diagram. The field theory loop equations for these cases show certain inhomogeneous terms suggesting the matrix model loop equations for the RP{sup 2} resolvent. (author)

Itoh, Taichi [BK21 Physics Research Division and Institute of Basic Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)]. E-mail: taichi@newton.skku.ac.kr

2003-07-01

121

Gravitational anomalies can be realized on the boundary of topologically ordered states in one higher dimension and are described by topological orders in one higher dimension. In this paper, we try to develop a general theory for both topological order and gravitational anomaly in any dimensions. (1) We introduce the notion of BF category to describe the braiding and fusion properties of topological excitations that can be point-like, string-like, etc. A subset of BF categories -- closed BF categories -- classify topological orders in any dimensions, while generic BF categories classify (potentially) anomalous topological orders that can appear at a boundary of a gapped quantum liquid in one higher dimension. (2) We introduce topological path integral based on tensor network to realize those topological orders. (3) Bosonic topological orders have an important topological invariant: the vector bundles of the degenerate ground states over the moduli spaces of closed spaces with different metrics. They may full...

Kong, Liang

2014-01-01

122

On gravitational dressing of 2D field theories in chiral gauge

International Nuclear Information System (INIS)

After giving a pedagogical review of the chiral gauge approach to 2D gravity, with particular emphasis on the derivation of the gravitational Ward identities, we discuss in some detail the interpretation of matter correlation functions coupled to gravity in chiral gauge. We argue that in chiral gauge no explicit gravitational dressing factor, analogue to the Liouville exponential in conformal gauge, is necessary for left-right symmetric matter operators. In particular, we examine the gravitationally dressed four-point correlation function of products of left and right fermions. We solve the corresponding gravitational Ward identity exactly: in the presence of gravity this four-point function exhibits a logarithmic short-distance singularity, instead of the power-law singularity in the absence of gravity. This rather surprising effect is non-perturbative in the gravitational coupling and is a sign for logarithms in the gravitationally dressed operator product expansions. We also discuss some perturbative evidence that the chiral Gross-Neveu model may remain integrable when coupled to gravity. (orig.)

123

On gravitational dressing of 2D field theories in chiral gauge

After giving a pedagogical review of the chiral gauge approach to 2D gravity, with particular emphasis on the derivation of the gravitational Ward identities, we discuss in some detail the interpretation of matter correlation functions coupled to gravity in chiral gauge. We argue that in chiral gauge no explicit gravitational dressing factor, analogue to the Lionville exponential in conformal gauge, is necessary for left-right symmetric matter operators. In particular, we examine the gravitationally dressed four-point correlation function of products of left and right fermions. We solve the corresponding gravitational Ward identity exactly: in the presence of gravity this four-point function exhibits a logarithmic short-distance singularity, instead of the power-law singularity in the absence of gravity. This rather surprising effect is non-perturbative in the gravitational coupling and is a sign for logarithms in the gravitationally dressed operator product expansions. We also discuss some perturbative evidence that the chiral Gross-Neveu model may remain integrable when coupled to gravity.

Bilala, Adel; Kogan, Ian I.

1995-02-01

124

Hypercharge flux in IIB and F-theory: anomalies and gauge coupling unification

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-Kähler deformations of the Calabi-Yau four-fold). Further, in such cases of geometrically massive U(1)s hypercharge flux can induce new anomalies of type in the massless spectrum, violating constraints in local models forbidding such anomalies. In particular this implies that it is possible to construct models exhibiting a U(1) PQ global symmetry which have hypercharge flux doublet-triplet splitting and no further exotics. 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 expectation values of certain closed-string fields, and therefore gauge coupling unification becomes tied to the question of moduli stabilisation.

Mayrhofer, Christoph; Palti, Eran; Weigand, Timo

2013-09-01

125

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.)

126

The Huygens principle and cosmological gravitational waves in the Regge-Wheeler gauge

International Nuclear Information System (INIS)

We study the propagation of axial gravitational waves in Friedmann universes. The evolution equation is obtained in the Regge-Wheeler gauge. The gravitational waves obey the Huygens principle in the radiation-dominated era, but in the matter-dominated universe their propagation depends on their wavelengths, with the scale fixed essentially by the Hubble radius. Short waves practically satisfy the Huygens principle while long waves can backscatter off the curvature of a spacetime

127

Tetrad fields and metric tensor in the gauge theory of gravitation

International Nuclear Information System (INIS)

The most relevant geometrical aspects of the gauge theory of gravitation are considered. A global definition of the tetrad fields is given and emphasis is placed on their role in defining an isomorphism between the tangent bundle of space-time and an appropriate vector bundle B associated to the gauge bundle. It is finally shown how to construct the fundamental geometrical objects on space-time, starting from B. (orig.)

128

The geometrical and gauge structure of a generalized theory of gravitation

International Nuclear Information System (INIS)

A generalized theory of gravitation is constructed in a superspace base manifold of eight dimensions with an octad of gauge fields and a superspace fiber bundle connection. The gauge structure is a non-compact unitary group U(i,j) contains SU(3) x SU(2) x U(1) which can be used as a unification scheme. Field equations with uniquely determined sources are derived from an action principle

129

Illusory are the conventional anomalies in the conformal-gauge two- dimensional quantum gravity

The exact solution in terms of Wightman functions is given to the BRS-formulated conformal-gauge two-dimensional quantum gravity coupled with D massless scalar fields. The solution is seen to be free of various anomalies. Its anomalous feature appears only in the B-field equation. The nilpotency violation of BRS charge for D not= 26, found by Kato and Ogawa, is shown to have been caused by their elimination of B-field. Feynman-diagrammatic method and path-integral formalism are shown to yield misleading results (e.g., FP-ghost number current anomaly), owing to the fact that these approaches are based on T*-product, which does not generally respect field equations.

Nakanishi, N

2001-01-01

130

Illusory are the conventional anomalies in the conformal-gauge two-dimensional quantum gravity

International Nuclear Information System (INIS)

The exact solution in terms of Wightman functions is given to the BRS-formulated conformal-gauge two-dimensional quantum gravity coupled with D massless scalar fields. The solution is seen to be free of various anomalies. Its anomalous feature appears only in the B-field equation. The nilpotency violation of BRS charge for D ? 26, found by Kato and Ogawa, is shown to have been caused by their elimination of B-field. Feynman-diagrammatic method and path-integral formalism are shown to yield misleading results (e.g., FP-ghost number current anomaly), owing to the fact that these approaches are based on T*-product, which does not generally respect field equations. (author)

131

From Gauge Anomalies to Gerbes and Gerbal Representations: Group Cocycles in Quantum Theory

Directory of Open Access Journals (Sweden)

Full Text Available In this paper I shall discuss the role of group cohomology in quantum mechanics and quantum field theory. First, I recall how cocycles of degree 1 and 2 appear naturally in the context of gauge anomalies. Then we investigate how group cohomology of degree 3 comes from a prolongation problem for group extensions and we discuss its role in quantum field theory. Finally, we discuss a generalization to representation theory where a representation is replaced by a 1-cocycle or its prolongation by a circle, and point out how this type of situations come up in the quantization of Yang-Mills theory.

J. Mickelsson

2010-01-01

132

Gravitational matter-antimatter asymmetry and four-dimensional Yang-Mills gauge symmetry

A formulation of gravity based on the maximum four-dimensional Yang-Mills gauge symmetry is studied. The theory predicts that the gravitational force inside matter (fermions) is different from that inside antimatter. This difference could lead to the cosmic separation of matter and antimatter in the evolution of the universe. Moreover, a new gravitational long-range spin-force between two fermions is predicted, in addition to the usual Newtonian force. The geometrical foundation of such a gravitational theory is the Riemann-Cartan geometry, in which there is a torsion. The results of the theory for weak fields are consistent with previous experiments.

Hsu, J. P.

1981-01-01

133

All-loop gauge couplings from anomaly cancellation in string effective theories

International Nuclear Information System (INIS)

We derive, to all orders in perturbation theory, the E8 gauge coupling and the modified dilaton-axion Kaehler potential for the effective theories of a class of d=4, N=1 heterotic string models. The derivation relies on an extended version of the Green-Schwarz anomaly cancellation mechanism, and exploits target-space duality invariance. Although we deal with field-dependent effective gauge couplings and scales in a non-renormalizable supergravity theory, we derive for them a renormalization group equation as a relation among dynamical fields. When expectation values of these fields are considered, our results agree with those previously obtained in renormalizable theories with N=1 global supersymmetry. We finally comment on possible generalizations of the present results. (orig.)

134

Gauge theories of gravitation a reader with commentaries

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

135

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

International Nuclear Information System (INIS)

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)

136

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

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

137

Exact Gravitational Gauge Structures and the Dirac Equation

Exact gauge structures arise in the evolution of spin-1/2 particles in conformally flat space-times. The corresponding Berry potentials can be Abelian or non-Abelian depending on the mass degeneracy of the system considered. Examples include de Sitter universes and maximal acceleration.

Lambiase, G

1998-01-01

138

Gauge dependence of effective gravitational field.II. Point-like measuring device

The role of the measurement process in resolving the gauge ambiguity of the effective gravitational potential is reexamined. The motion of a classical point-like particle in the field of an arbitrary linear source, and in the field of another point-like particle is investigated. It is shown that in both cases the value of the gravitational field read off from the one-loop effective action of the testing particle depends on the Feynman weighting parameter. The found dependence is essential in that it persists in the expression for the gravitational potential. This result disproves the general conjecture about gauge independence of the effective equations of motion of classical point-like particles.

Gribouk, T S; Pronin, P I; Gribouk, Taras S.; Kazakov, Kirill A.; Pronin, Petr I.

2004-01-01

139

Gauge problem in the gravitational self-force: First post-Newtonian force in the Regge-Wheeler gauge

International Nuclear Information System (INIS)

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

140

International Nuclear Information System (INIS)

A systematic method is developed to study the classical motion of a mass point in gravitational gauge field. First, by using Mathematica, a spherical symmetric solution of the field equation of gravitational gauge field is obtained, which is just the traditional Schwarzschild solution. Combining the principle of gauge covariance and Newton's second law of motion, the equation of motion of a mass point in gravitational field is deduced. Based on the spherical symmetric solution of the field equation and the equation of motion of a mass point in gravitational field, we can discuss classical tests of gauge theory of gravity, including the deflection of light by the sun, the precession of the perihelia of the orbits of the inner planets and the time delay of radar echoes passing the sun. It is found that the theoretical predictions of these classical tests given by gauge theory of gravity are completely the same as those given by general relativity.

141

The trumpet solution from spherical gravitational collapse with puncture gauges

We investigate the stationary end-state obtained by evolving a collapsing spherical star with the gauges routinely adopted to study puncture black holes. We compare the end-state of the collapse with the trumpet solution found in the evolution of a single wormhole slice and show that the two solutions closely agree. We demonstrate that the agreement is caused by the use of the Gamma-driver shift condition, which allows the matter to fall inwards into a region of spacetime that is not resolved by the numerical grid, and which simultaneously finds the stationary coordinates of the trumpet outside the matter.

Thierfelder, Marcus; Hilditch, David; Bruegmann, Bernd; Rezzolla, Luciano

2010-01-01

142

International Nuclear Information System (INIS)

Identification of the diagrams that can lead to gauge anomalies in the (minimal) Lorentz- and CPT-violating extension of quantum electrodynamics reveal these to be the electron self-energy and vertex correction (related to the Ward–Takahashi identity), the photon self-energy (related to the vacuum polarization tensor transversality) and the three-photon vertex diagrams. All but the latter were explicitly verified to be free of anomalies to first order in loop expansion. Here we provide this remaining evaluation and verify the absence of anomalies in this process. (paper)

143

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

144

Axial vacuum symmetry of the unified gauge theories with the gravitational mechanism of instability

International Nuclear Information System (INIS)

The problem of stable-state determination is considered in unified gauge theories involving gravitation. The gravitational fields are examined at a classical level. The self-consistent set of field equations is studied in the semiclassical approach. A new determination of stable states is given. If the conditions of the determination are not satisfied then the vacuum state may be metastable. For the case of axial symmetry the metastable Z-type states are shown to cancel if these states are symmetric. (author)

145

String theory applications in gravitational problems and gauge theories

In this dissertation, we review the study of quark and monopole bound-state potentials within the gauge/gravity correspondence. Their behaviors often differ from what is expected on general physical grounds and field-theory considerations. We identify the configurations of physical interest by examining the stability of the string (brane) solutions dual to the flux tubes between the bound states. In particular, we formulate and prove several general statements concerning the perturbative stability of such string (brane) solutions, relevant for these configurations in a general class of backgrounds. We apply the results to N = 4 SYM and N = 1 at finite temperature and at generic points of the Coulomb branch. In all cases, the problematic regions are found to be unstable and hence physically irrelevant.

Siampos, Konstadinos

2010-01-01

146

Stochastic quantization of gauge, gravitational and string fields

International Nuclear Information System (INIS)

The stochastic quantization method of Parisi and Wu and its application to gauge fields are briefly reviewed. The method is then generalized so as to make it applicable to Einstein gravity. The generalization is based on the existence of a preferred metric in field configuration space and involves Ito's calculus. In the nonlinear case the indefiniteness of the Euclidean Einstein action necessitates to generalize the stochastic formalism further to Lorentzian space-times. The formalism is shown to imply the path integral measure of De Witt, a causal Feynman propagator, and a consistent stochastic perturbation theory. Finally it is shown how stochastic quantization resolves the indefiniteness problem in free bosonic string field theory. (Author)

147

Electroweak Gauge-Boson Production at Small q_T: Infrared Safety from the Collinear Anomaly

Using methods from effective field theory, we develop a novel, systematic framework for the calculation of the cross sections for electroweak gauge-boson production at small and very small transverse momentum q_T, in which large logarithms of the scale ratio M_V/q_T are resummed to all orders. These cross sections receive logarithmically enhanced corrections from two sources: the running of the hard matching coefficient and the collinear factorization anomaly. The anomaly leads to the dynamical generation of a non-perturbative scale q_* ~ M_V e^{-const/\\alpha_s(M_V)}, which protects the processes from receiving large long-distance hadronic contributions. Expanding the cross sections in either \\alpha_s or q_T generates strongly divergent series, which must be resummed. As a by-product, we obtain an explicit non-perturbative expression for the intercept of the cross sections at q_T=0, including the normalization and first-order \\alpha_s(q_*) correction. We perform a detailed numerical comparison of our predicti...

Becher, Thomas; Wilhelm, Daniel

2011-01-01

148

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.)

149

Gauge-invariant gravitational wave modes in pre-big bang cosmology

International Nuclear Information System (INIS)

The t<0 branch of pre-big bang cosmological scenarios is subject to a gravitational wave instability. The unstable behaviour of tensor perturbations is derived in a very simple way in Hwang's covariant and gauge-invariant formalism developed for extended theories of gravity. A simple interpretation of this instability as the effect of an ''antifriction'' is given, and it is argued that a universe must eventually enter the expanding phase. (orig.)

150

Anomaly inflow and thermal equilibrium

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

151

International Nuclear Information System (INIS)

The dynamics of metric perturbations is explored in the gravity theory with anomaly-induced quantum corrections. Our first purpose is to derive the equation for gravitational waves in this theory on the general homogeneous and isotropic background, and then verify the stability of such background with respect to metric perturbations. The problem under consideration has several interesting applications. Our first purpose is to explore the stability of the classical cosmological solutions in the theory with quantum effects taken into account. There is an interesting literature about stability of Minkowski and de Sitter spaces and here we extend the consideration also to the radiation and matter dominated cosmologies. Furthermore, we analyze the behavior of metric perturbations during inflationary period, in the stable phase of the Modified Starobinsky inflation

152

Classical Gravitational Interactions and Gravitational Lorentz Force

Digital Repository Infrastructure Vision for European Research (DRIVER)

In quantum gauge theory of gravity, the gravitational field is represented by gravitational gauge field. The field strength of gravitational gauge field has both gravitational electric component and gravitational magnetic component. In classical level, gauge theory of gravity gives out classical Newtonian gravitational interactions in a relativistic form. Besides, it gives out gravitational Lorentz force which is the gravitational force on a moving object in gravitational ma...

Wu, Ning

2005-01-01

153

Self-dual cosmic strings and gravitating vortices in gauged sigma models

DEFF Research Database (Denmark)

Cosmic strings are considered in two types of gauged sigma models, which generalize the gravitating Abelian Higgs model. The two models differ by whether the U(1) kinetic term is of the Maxwell or Chern-Simons form. We obtain the self-duality conditions for a general two-dimensional target space defined in terms of field dependent "dielectric functions". In particular, we analyze analytically and numerically the equations for the case of O(3) models (two-sphere as target space), and find cosmic string solutions of several kinds as well as gravitating vortices. We classify the solutions by their flux and topological charge. We note an interesting connection between the Maxwell and Chern-Simons type models, which is responsible for simple relations between the self-dual solutions of both types. There is however a significant difference between the two systems, in that only the Chern-Simons type sigma model gives rise to spinning cosmic vortices.

Verbin, Y.; Madsen, SØren Peder

2003-01-01

154

Gravitational Corrections for Supersymmetric Gauge Theories with Flavors via Matrix Models

We study the gravitational corrections to the F-term in four-dimensional N=1 U(N) gauge theories with flavors, using the Dijkgraaf-Vafa theory. We derive a compact formula for the annulus contribution in terms of the prime form on the matrix model curve. Remarkably, the full R^2 correction can be reproduced as a special momentum sector of a single c=1 CFT correlator, which closely resembles that in the bosonization of fermions on Riemann surfaces. The N=2 limit of the torus contribution agrees with the multi-instanton calculations as well as the topological A-model result. The planar contributions, on the other hand, have no counterpart in the topological gauge theories, and we speculate about the origin of these terms.

Fuji, H; Fuji, Hiroyuki; Mizoguchi, Shun'ya

2004-01-01

155

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

156

Consistent and covariant anomalies in the overlap formulation of chiral gauge theories

In this letter we show how the covariant anomaly emerges in the overlap scheme. We also prove that the overlap scheme correctly reproduces the anomaly in the flavour currents such as $j^5_\\mu$ in vector like theories like QCD.

Randjbar-Daemi, S

1997-01-01

157

Does the Neptunian system of satellites challenge a gravitational origin for the Pioneer anomaly?

If the Pioneer Anomaly was a genuine dynamical effect of gravitational origin, it should also affect the orbital motions of the solar system's bodies moving in the space regions in which the PA manifested itself in its presently known form, i.e. as a constant and uniform acceleration approximately directed towards the Sun with a non-zero magnitude (8.74+/-1.33) x 10^-10 m s^-2 after 20 au from the Sun. We preliminarily investigate its effects on the orbital motions of the Neptunian satellites Triton, Nereid and Proteus, located at about 30 au from the Sun, both analytically and numerically. The analytical calculations show that the PA-induced radial and transverse perturbations of Triton are of the order of a few km yr^-1, those of Nereid are about 10+/-100 km yr^-1, while Proteus experiences radial and transverse shifts of the order of 0.1 km yr^-1. The out-of-plane perturbations are negligible, apart from that of Nereid which amounts to about 20 km yr^-1. The corresponding orbital uncertainties obtained fro...

Iorio, Lorenzo

2009-01-01

158

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

159

Quantum topology and global anomalies

Anomalies are ubiquitous features in quantum field theories. They can ruin the consistency of such theories and put significant restrictions on their viability, especially in dimensions higher than four. Global gauge and gravitational anomalies are to date, one of the scant powerful and probing tools available to physicists in the pursuit of uniqueness.This monograph is one of the very few that specializes in the study of global anomalies in quantum field theories. A discussion of various issues associated to three dimensional physics - the Chern-Simons-Witten theories - widen the scope of thi

Baadhio, R A

1996-01-01

160

BRS cohomology and topological anomalies

Energy Technology Data Exchange (ETDEWEB)

The occurrence of non-abelian anomalies in gauge theories and gravitation, first discovered via perturbative techniques, is now completely explained from the mathematical point of view by means of the family index theorem of Atiyah and Singer. Here we make contact between this approach and BRS cohomology, by showing that they yield the same non-abelian anomalies, provided a certain restriction to ''local'' functionals is not introduced from the very beginning. In particular, this solves the ''unicity'' problem for this kind of anomalies. Local BRS cohomology is still relevant for the abelian case. (orig.).

Falqui, G.; Reina, C.

1985-12-03

161

BRS cohomology and topological anomalies

The occurrence of non-abelian anomalies in gauge theories and gravitation, first discovered via perturbative techniques, is now completely explained from the mathematical point of view by means of the family index theorem of Atiyah and Singer. Here we make contact between this approach and BRS cohomology, by showing that they yield the same non-abelian anomalies, provided a certain restriction to “local” functionals is not introduced from the very beginning. In particular, this solves the “unicity” problem for this kind of anomalies. Local BRS cohomology is still relevant for the abelian case.

Falqui, Gregorio; Reina, Cesare

1985-09-01

162

BRS cohomology and topological anomalies

International Nuclear Information System (INIS)

The occurrence of non-abelian anomalies in gauge theories and gravitation, first discovered via perturbative techniques, is now completely explained from the mathematical point of view by means of the family index theorem of Atiyah and Singer. Here we make contact between this approach and BRS cohomology, by showing that they yield the same non-abelian anomalies, provided a certain restriction to ''local'' functionals is not introduced from the very beginning. In particular, this solves the ''unicity'' problem for this kind of anomalies. Local BRS cohomology is still relevant for the abelian case. (orig.)

163

Consistent and covariant anomalies in the overlap formulation of chiral gauge theories

International Nuclear Information System (INIS)

In this letter we show how the covariant anomaly emerges in the overlap scheme. We also prove that the overlap scheme correctly reproduces the anomaly in the flavour currents such as j5? in vector like theories like QCD. (author). 6 refs

164

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

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

165

Covariant Lorentz anomalies in higher dimensional space

International Nuclear Information System (INIS)

The covariant Lorentz anomalies are evaluated by both the path integral and the topological methods, when Weyl fermions couple with the gauge and gravitational fields. In 2,4,6-dimensional curved space, the difference between the results obtained by the two methods is removed by counterterms and the equivalence of both methods is proved. It is shown that the Lorentz anomalies in flat space of arbitrary dimensions are eliminated. (author)

166

Conditions for absence of global SU(2) anomaly for four-dimensional gauge groups

International Nuclear Information System (INIS)

Proofs are given group theoretically for the absence of the global SU(2) (Witten) anomaly for any compact Lie group GcontainsSU(2) satisfying Pi4(G) = 0 (Pi4 is the four-dimensional homotopy group). It is shown that the number of fermion zero modes is even for G = SO(N) (N?7) and the five exceptional groups G2, F4, E6, E7, and E8. The absence of the Witten anomaly for the SU(N) (N?3) groups requires freedom from the perturbative (triangle) anomaly

167

Anomaly cancellation and gauge group of the standard model in NCG

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

168

Covariant anomalies and functional determinants

International Nuclear Information System (INIS)

We analize the algebraic structure of consistent and covariant anomalies in gauge and gravitational theories: using a complex extension of the Lie algebra it is possible to describe them in a unified way. Then we study their representations by means of functional determinants, showing how the algebraic solution determines the relevant operators for the definition of the effective action. Particular attention is devoted to the Lorentz anomaly: we obtain by functional methods the covariant anomaly for the spin-current and for the energy-momentum tensor in presence of a curved background. With regard to the consistent sector we are able to give a general functional solution only for d = 2: using the characterization derived from the extended algebra, we find a continuous family of operators whose determinant describes the effective action of chiral spinors in curved space. We compute this action and we generalize the result in presence of a U(1) gauge connection. (orig.)

169

Errata and Addenda to "Anomaly Cancellation Condition in Lattice Gauge Theory"

We correct some intermediate expressions and arguments in Nucl. Phys. B 585 (2000) 471--513. The main results do not change. We also mention some additional observations, including a constraint on a coefficient of the possible nontrivial anomaly which was not given in the paper.

Igarashi, H; Suzuki, H; Igarashi, Hiroshi; Okuyama, Kiyoshi; Suzuki, Hiroshi

2000-01-01

170

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

2011-10-01

171

We present an algorithm for calculating the metric perturbations and gravitational self-force for extreme-mass-ratio inspirals (EMRIs) with eccentric orbits. The massive black hole is taken to be Schwarzschild and metric perturbations are computed in Lorenz gauge. The perturbation equations are solved as coupled systems of ordinary differential equations in the frequency domain. Accurate local behavior of the metric is attained through use of the method of extended homogeneous solutions and mode-sum regularization is used to find the self-force. We focus on calculating the self-force with sufficient accuracy to ensure its error contributions to the phase in a long term orbital evolution will be $\\delta\\Phi \\lesssim 10^{-2}$ radians. This requires the orbit-averaged force to have fractional errors $\\lesssim 10^{-8}$ and the oscillatory part of the self-force to have errors $\\lesssim 10^{-3}$ (a level frequently easily exceeded). Our code meets this error requirement in the oscillatory part, extending the reach...

Osburn, Thomas; Evans, Charles; Hopper, Seth

2014-01-01

172

AdS solutions in gauge supergravities and the global anomaly for the product of complex two-cycles

International Nuclear Information System (INIS)

Cohomological methods are applied for the special set of solutions corresponding to rotating branes in arbitrary dimensions, AdS black holes (which can be embedded in ten or eleven dimensions), and gauge supergravities. A new class of solutions is proposed, the Hilbert modular varieties, which consist of the 2n-fold product of the two-spaces Hn /? (where Hn denotes the product of n upper half-planes, H 2, equipped with the co-compact action of ? is contained in SL(2, R)n) and (H n)*/? (where (H 2)*=H 2? and ? is a congruence subgroup of SL(2, R) n). The cohomology groups of the Hilbert variety, which inherit a Hodge structure (in the sense of Deligne), are analyzed, as well as bifiltered sequences, weight and Hodge filtrations, and it is argued that the torsion part of the cuspidal cohomology is involved in the global anomaly condition. Indeed, in the presence of the cuspidal part, all cohomology classes can be mapped to the boundary of the space and the cuspidal contribution can be involved in the global anomaly condition. (orig.)

173

International Nuclear Information System (INIS)

It is shown that on curved backgrounds, the Coulomb gauge Faddeev-Popov operator can have zero modes even in the Abelian case. These zero modes cannot be eliminated by restricting the path integral over a certain region in the space of gauge potentials. The conditions for the existence of these zero modes are studied for static spherically symmetric spacetimes in arbitrary dimensions. For this class of metrics, the general analytic expression of the metric components in terms of the zero modes is constructed. Such expression allows one to find the asymptotic behavior of background metrics, which induce zero modes in the Coulomb gauge, an interesting example being the three-dimensional anti-de Sitter spacetime. Some of the implications for quantum field theory on curved spacetimes are discussed.

174

Exact results in two-dimensional chiral hydrodynamics with gravitational anomalies

International Nuclear Information System (INIS)

An exact formulation of two-dimensional chiral hydrodynamics with diffeomorphism and conformal anomalies is provided. The constitutive relation involving the stress tensor is computed. It reveals a one parameter class of solutions which is a new result. For a particular value of this parameter, the results found in the gradient expansion scheme are reproduced. Moreover, the constitutive relation is analogous to the corresponding relation for an ideal fluid, appropriately modified to include the chirality property, which has also been derived here. (orig.)

175

Exact results in two-dimensional chiral hydrodynamics with gravitational anomalies

Energy Technology Data Exchange (ETDEWEB)

An exact formulation of two-dimensional chiral hydrodynamics with diffeomorphism and conformal anomalies is provided. The constitutive relation involving the stress tensor is computed. It reveals a one parameter class of solutions which is a new result. For a particular value of this parameter, the results found in the gradient expansion scheme are reproduced. Moreover, the constitutive relation is analogous to the corresponding relation for an ideal fluid, appropriately modified to include the chirality property, which has also been derived here. (orig.)

Banerjee, Rabin [S. N. Bose National Centre for Basic Sciences, Kolkata (India)

2014-04-15

176

We address the question of whether the LambdaCDM model produces enough substructure in galaxy scale dark matter halos to cause the observed image flux anomalies in lensed QSOs observed in the radio and mid-infrared. We create a very large number of simulated lenses with finite source sizes to compare with the data. After analysing these simulations, our conclusions are: 1) The finite size of the source is important. The point source approximation commonly used can cause large and biased results. 2) When we randomly select lens models that are distorted from a Singular Isothermal Ellipsoid in reasonable ways, but do not contain substructure, the flux anomalies are not reproduced. 3) We find new upper bounds on the amount of substructure from the constraint that no simple single-galaxy lenses have been observed with a single source having more than four well separated images. 4) The lower bound on the amount of substructure is set by the frequency of image flux anomalies and is largely a bound on the surface ma...

Metcalf, R Benton

2010-01-01

177

In a previous paper we investigate a Lagrangian field theory for the gravitational field, which is there represented by a section {?} of the coframe bundle over Minkowski spacetime (M~=R4,g?,D?,?g?,?). Such theory, under appropriate conditions, has been proved to be equivalent to a Lorentzian spacetime structure (M~=R4,g,D,?g,?) where the metric tensor g satisfies the Einstein field equation. Here, we first recall that according to quantum field theory ideas gravitation is described by a Lagrangian theory of a possible massive graviton field (generated by matter fields and coupling also to itself) living in Minkowski spacetime. The massive graviton field is moreover supposed to be represented by a symmetric tensor field h carrying the representations of spin two and zero of the Lorentz group. Such a field, then (as it is well known) must necessarily satisfy the gauge condition given by Eq.(10) below. Next, we introduce an ansatz relating h with the 1-form fields {?}. Then, using the Clifford bundle formalism we derive from our Lagrangian theory the exact wave equation for the graviton and investigate the role of the gauge condition given by Eq.(10) by asking the question: does Eq.(10) fix any gauge condition for the field g of the effective Lorentzian spacetime structure (M~=R4,g,D,?g,?) that represents the field h in our theory? We show that no gauge condition is fixed a priory, as it is the case in General Relativity. Moreover we prove that if we use Logunov gauge condition, i.e., D??(-detgg?? = 0 then only a restricted class of coordinate systems (including harmonic ones) are allowed by the theory.

Da Rocha, Rolda~O.; Rodrigues, Waldyr A.

2010-12-01

178

Survival of new physics: Anomaly-free neutral gauge boson at the LHC

An anomaly-free U(1)? effective Lagrangian as a benchmark of new physics beyond the standard model is proposed to survey the maximal parameter space constrained by the precise electroweak measurements at the Large Electron-Positron Collider (LEP) and direct detection of the dilepton decay channel at ? {s} = 7 TeV at the Large Hadron Collider (LHC). By the global fit of the effective couplings of the Z boson to the Standard Model fermions, parameters ?11, ?21 and g???31 related to mixings and r related to the U(1)? charge assignment are bounded. The allowed areas are plotted not only in the r-g?? plane, but also in the mZ?-g?? plane. They show that a sub-TeV Z? is still permissible as long as the coupling g?? is of order 0.01. The results hint at possible new physics beyond the standard model. A prediction of the possible signal for the dilepton decay channel at ? {s} = 14 TeV at LHC is also provided.

Zhang, Ying; Wang, Qing

2014-03-01

179

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)

180

Neutrino anomalies in a gauge mediated model with trilinear R violation

International Nuclear Information System (INIS)

The structure of neutrino masses and mixing resulting from trilinear R violating interactions is studied in the presence of gauge mediated supersymmetry breaking. Neutrino masses arise in this model at the tree level through the renormalization-group-induced vacuum expectation values of the sneutrinos and also through direct contribution at one loop. The relative importance of these contributions is determined by the values of the strong- and weak-coupling constants. In the case of purely ?' couplings, the tree contribution dominates over the one-loop diagram. In this case, one simultaneously obtains atmospheric neutrino oscillations and quasivacuum oscillations of the solar neutrinos if all the ?' couplings are assumed to be of similar magnitudes. If R parity violation arises from the trilinear ? couplings, then the loop-induced contribution dominates over the tree level. One cannot simultaneously explain the solar and atmospheric deficit in this case if all the ? couplings are of similar magnitude. This, however, becomes possible with hierarchical ? and we give a specific example of this

181

Evolutionary models have been calculated for Pop II stars of 0.5 to 1.0$M_\\odot$ from the pre-main-sequence to the lower part of the giant branch. Rosseland opacities and radiative accelerations were calculated taking into account the concentration variations of 28 chemical species, including all species contributing to Rosseland opacities in the OPAL tables. The effects of radiative accelerations, thermal diffusion and gravitational settling are included. While models were calculated both for Z=0.00017 and 0.0017, we concentrate on models with Z=0.00017 in this paper. These are the first Pop II models calculated taking radiative acceleration into account. It is shown that, at least in a 0.8$M_\\odot$ star, it is a better approximation not to let Fe diffuse than to calculate its gravitational settling without including the effects of $g_{rad}(Fe)$. In the absence of any turbulence outside of convection zones, the effects of atomic diffusion are large mainly for stars more massive than 0.7$M_\\odot$. Overabundan...

Richard, O; Richer, J; Turcotte, S; Turck-Chièze, S; Van den Berg, D A; Berg, Don A. Vanden

2002-01-01

182

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

183

International Nuclear Information System (INIS)

The lectures given cover the topological effects in gauge field theories, fermionic chiral anomalies, and some relationships between the two. Gauge field theories in three and four space-time dimensions are considered. Topological terms as external U(1) functional gauge potential connections in field space are discussed. Both the structure and physical impact of anomalies are described. 17 refs

184

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

A planetary microlensing signal is generally characterized by a short-term perturbation to the standard single lensing light curve. A subset of binary-source events can produce perturbations that mimic planetary signals, thereby introducing an ambiguity between the planetary and binary-source interpretations. In this paper, we present the analysis of the microlensing event MOA-2012-BLG-486, for which the light curve exhibits a short-lived perturbation. Routine modeling not considering data taken in different passbands yields a best-fit planetary model that is slightly preferred over the best-fit binary-source model. However, when allowed for a change in the color during the perturbation, we find that the binary-source model yields a significantly better fit and thus the degeneracy is clearly resolved. This event not only signifies the importance of considering various interpretations of short-term anomalies, but also demonstrates the importance of multi-band data for checking the possibility of false-positive planetary signals.

Hwang, K.-H.; Choi, J.-Y.; 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.; MOA Collaboration; 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.; ?FUN Collaboration; Albrow, M. D.; Bachelet, E.; Batista, V.; Brillant, S.; Caldwell, J. A. R.; Cassan, A.; Cole, A.; Corrales, E.; Coutures, Ch.; Dieters, S.; Dominis Prester, D.; 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.; The PLANET Collaboration; Bramich, D. M.; Dominik, M.; Horne, K.; Browne, P.; Hundertmark, M.; Ipatov, S.; Kains, N.; Snodgrass, C.; Steele, I. A.; Street, R. A.; The RoboNet Collaboration

2013-11-01

185

Gauge invariance and string interactions in a generalized theory of gravitation

International Nuclear Information System (INIS)

The gauge invariance of the Lagrangian in the nonsymmetric extension of general relativity is investigated. The skew parts of the nonsymmetric Hermitian g/sub munu/, in the weak-field approximation, act as gauge potentials that correspond to the exchange of massless scalar mesons between one-dimensionally extended objects (strings) in space-time. For open strings a massive vector particle, associated with the torsion, is also exchanged between the end points of the strings

186

Anomaly-free model in six dimensions

Energy Technology Data Exchange (ETDEWEB)

We show that a gauged supergravity theory based on E/sub 6/ x E/sub 7/ x U(1) is free of gauge and gravitational anomalies in six dimensions. It compactifies to (Minkowski)/sup 4/ x S/sup 2/ by the standard monopole mechanism. With a monopole of strength n in E/sub 6/, the resulting four-dimensional theory exhibits chiral SO(10) x U(1) with 2vertical strokenvertical stroke families (and no antifamilies). Supersymmetry is broken.

Randjbar-Daemi, S.; Salam, A.; Sezgin, E.; Strathdee, J.

1985-02-21

187

International Nuclear Information System (INIS)

A complete Lagrangian and Hamiltonian description of the theory of self-gravitating lightlike matter shells is given in terms of gauge-independent geometric quantities. For this purpose the notion of an extrinsic curvature for a null-like hypersurface is discussed and the corresponding Gauss-Codazzi equations are proved. These equations imply Bianchi identities for spacetimes with null-like, singular curvature. The energy-momentum tensor density of a lightlike matter shell is unambiguously defined in terms of an invariant matter Lagrangian density. The Noether identity and Belinfante-Rosenfeld theorem for such a tensor density are proved. Finally, the Hamiltonian dynamics of the interacting 'gravity+matter' system is derived from the total Lagrangian, the latter being an invariant scalar density

188

In a previous paper we investigate a Lagrangian field theory for the gravitational field (which is there represented by a section {g^a} of the orthonormal coframe bundle over Minkowski spacetime that was shown under appropriate conditions to be equivalent to a Lorentzian spacetime structure where the associated metric tensor satisfies Einstein field equations. Here, we first recall that according to quantum field theory ideas gravitation is to be described by a Lagrangian theory of a possible massive graviton field (generated by matter fields and coupling also to itself) living in Minkowski spacetime. Moreover the graviton field is supposed to be represented by a symmetric tensor field h, carrying the representations of spin two and zero of the Lorentz group. Such a field, then (as it is well known) must necessarily satisfy the gauge condition given by Eq.(3) below. Next, we introduce an ansatz relating h to the 1-form fields {g^a}. Then, using the Clifford bundle formalism we derive from our Lagragian theory...

da Rocha, Roldao

2008-01-01

189

It is shown that the axial and polar perturbations of the spherically symmetric black hole can be described in a gauge-invariant way. The reduced phase space describing gravitational waves outside of the horizon is described by the gauge-invariant quantities. Both degrees of freedom fulfill generalized scalar wave equation. For the axial degree of freedom the radial part of the equation corresponds to the Regge-Wheeler result (Phys. Rev. 108, 1063-1069 (1957)) and for the polar one we get Zerilli result (Phys. Rev. D2, 2141-2160 (1970)), see also Chandrasekhar (The Mathematical Theory of Black Holes,(Clarendon Press Oxford, 1983)), Moncrief (Annals of Physics 88, 323-342 (1974)) for both. An important ingredient of the analysis is the concept of quasilocality which does duty for the separation of the angular variables in the usual approach. Moreover, there is no need to represent perturbations by normal modes (with time dependence $\\exp(-ikt)$), we have fields in spacetime and the Cauchy problem for them is w...

Jezierski, J

1999-01-01

190

Recently, with the ``bounching photon'' treatment, the gauge invariance of the response of an interferometer to scalar gravitational waves (SGWs) has been demonstred in its full frequency dependence in three different gauges well known in literature, while in previous works it was been shown only in the low frequencies approximation. In this paper the analysis of the response function for SGWs is generalized in its full angular dependence and directly in the gauge of the local observer, which is the gauge of a laboratory enviroment on Earth. The result is used for anlyzing the cross - correlation between the two LIGO interferometers in their advanced configuration for a potential detection of a stochastic bacground of SGWs. An inferior limit for the integration time of a potential detection is released.

Corda, C

2006-01-01

191

Path integral quantization of gravitational interactions

International Nuclear Information System (INIS)

Some of the local symmetry properties of quantum field theory in curved space-time and quantized gravitational interactions are discussed. We concentrate on local symmetry properties, and thus the asymptotically flat space-time is assumed, whenever necessary, in the hope that the precise boundary conditions will not modify the short distance structure in quantum theory. We adopt the DeWitt-Faddeev-Popov prescription of the Feynman path integral with a complete gauge fixing. The topics discussed include: (i) A brief review of the path integral derivation of chiral anomalies in flat space-time. (ii) The specification of the gravitational path integral measure, which avoids all the ''fake'' gravitational anomalies, and the applications of this path integral prescription to 1) effective potential in generalized Kaluza-Klein theory, 2) 4-dimensional conformal anomalies, 3) conformal symmetry in pure conformal gravity, 4) bosonic string theory as a gravitational theory in d = 2, 5) Virasoro condition and the Wheeler-DeWitt equation in the path integral formalism, 6) gravitational anomalies and the definition of the energy-momentum tensor. (author)

192

Digital Repository Infrastructure Vision for European Research (DRIVER)

Parity nonconservation in the beta-decay processes is considered as fundamental property of weak interactions. Nevertheless, this property can be treated as anomaly, because in fundamental interactions of the rest types parity is conserved. Analogously, anomaly in the short-duration strong-current pulse discharges is well known. The essence of this phenomenon consists in generation of local high-temperature plasma formations (LHTF) with the typical values of its thermodynami...

Fisenko, S. I.

2001-01-01

193

Search for light massive gauge bosons as an explanation of the $(g-2)_\\mu$ anomaly at MAMI

A massive, but light abelian U(1) gauge boson is a well motivated possible signature of physics beyond the Standard Model of particle physics. In this paper, the search for the signal of such a U(1) gauge boson in electron-positron pair-production at the spectrometer setup of the A1 Collaboration at the Mainz Microtron (MAMI) is described. Exclusion limits in the mass range of 40 MeV up to 300 MeV with a sensitivity in the mixing parameter of down to $\\epsilon^2 = 8\\times 10^{-7}$ are presented. A large fraction of the parameter space has been excluded where the discrepancy of the measured anomalous magnetic moment of the muon with theory might be explained by an additional U(1) gauge boson.

Merkel, H; Gayoso, C Ayerbe; Beranek, T; Beri?i?, J; Bernauer, J C; Böhm, R; Bosnar, D; Correa, L; Debenjak, L; Denig, A; Distler, M O; Esser, A; Fonvieille, H; Friš?i?, I; de la Paz, M Gómez Rodríguez; Hoek, M; Kegel, S; Kohl, Y; Middleton, D G; Mihovilovi?, M; Müller, U; Nungesser, L; Pochodzalla, J; Rohrbeck, M; Ron, G; Majos, S Sánchez; Schlimme, B S; Schoth, M; Schulz, F; Sfienti, C; Širca, S; Thiel, M; Tyukin, A; Weber, A; Weinriefer, M

2014-01-01

194

Search at the Mainz Microtron for light massive gauge bosons relevant for the muon g-2 anomaly.

A massive, but light, Abelian U(1) gauge boson is a well-motivated possible signature of physics beyond the standard model of particle physics. In this Letter, the search for the signal of such a U(1) gauge boson in electron-positron pair production at the spectrometer setup of the A1 Collaboration at the Mainz Microtron is described. Exclusion limits in the mass range of 40??MeV/c^{2} to 300??MeV/c^{2}, with a sensitivity in the squared mixing parameter of as little as ?^{2}=8×10^{-7} are presented. A large fraction of the parameter space has been excluded where the discrepancy of the measured anomalous magnetic moment of the muon with theory might be explained by an additional U(1) gauge boson. PMID:24949757

Merkel, H; Achenbach, P; Ayerbe Gayoso, C; Beranek, T; Beri?i?, J; Bernauer, J C; Böhm, R; Bosnar, D; Correa, L; Debenjak, L; Denig, A; Distler, M O; Esser, A; Fonvieille, H; Friš?i?, I; Gómez Rodríguez de la Paz, M; Hoek, M; Kegel, S; Kohl, Y; Middleton, D G; Mihovilovi?, M; Müller, U; Nungesser, L; Pochodzalla, J; Rohrbeck, M; Ron, G; Sánchez Majos, S; Schlimme, B S; Schoth, M; Schulz, F; Sfienti, C; Sirca, S; Thiel, M; Tyukin, A; Weber, A; Weinriefer, M

2014-06-01

195

Search at the Mainz Microtron for Light Massive Gauge Bosons Relevant for the Muon g-2 Anomaly

A massive, but light, Abelian U(1) gauge boson is a well-motivated possible signature of physics beyond the standard model of particle physics. In this Letter, the search for the signal of such a U(1) gauge boson in electron-positron pair production at the spectrometer setup of the A1 Collaboration at the Mainz Microtron is described. Exclusion limits in the mass range of 40 MeV/c2 to 300 MeV/c2, with a sensitivity in the squared mixing parameter of as little as ?2=8×10-7 are presented. A large fraction of the parameter space has been excluded where the discrepancy of the measured anomalous magnetic moment of the muon with theory might be explained by an additional U(1) gauge boson.

Merkel, H.; Achenbach, P.; Ayerbe Gayoso, C.; Beranek, T.; Beri?i?, J.; Bernauer, J. C.; Böhm, R.; Bosnar, D.; Correa, L.; Debenjak, L.; Denig, A.; Distler, M. O.; Esser, A.; Fonvieille, H.; Friš?i?, I.; Gómez Rodríguez de la Paz, M.; Hoek, M.; Kegel, S.; Kohl, Y.; Middleton, D. G.; Mihovilovi?, M.; Müller, U.; Nungesser, L.; Pochodzalla, J.; Rohrbeck, M.; Ron, G.; Sánchez Majos, S.; Schlimme, B. S.; Schoth, M.; Schulz, F.; Sfienti, C.; Širca, S.; Thiel, M.; Tyukin, A.; Weber, A.; Weinriefer, M.; A1 Collaboration

2014-06-01

196

Without gravity, you would float into space. Gravity pulls matter together: it holds us onto the Earth, it holds the Earth in orbit around the sun and it holds our solar system in orbit about the centre of the galaxy. Everything with mass feels the attraction of gravity. The strength of the attraction between 2 objects depends on their masses. Despite its omnipresence, gravity is the weakest of the 4 forces. It is insignificant at the scale of human beings: when a group of visitors walks past, gravity doesn't pull you towards them! At even smaller scales, the gravitational pull between the electron and the proton is about 1040 times weaker than the electromagnetic attraction between them. Text for the interactive: Why does the same mass weigh more on the Earth than on the moon ?

197

On the simple evaluation of chiral anomalies in the path integral approach

International Nuclear Information System (INIS)

We comment on the relation between the Schwinger's proper time method and the one-dimensional supersymmetric path integral method in the evaluation of chiral anomalies in gauge and gravitational interactions. For this purpose, we introduce a modified one-dimensional path integral which is directly related to the proper time method by a Legendre transformation. This modified scheme provides a simple way of evaluating chiral anomalies. The one-dimensional path integral method is also shown to work for the trace anomaly in 4-dimensional flat space-time. (author)

198

The conformal anomaly and the neutral currents sector of the Standard Model

International Nuclear Information System (INIS)

We elaborate on the structure of the graviton-gauge-gauge vertex in the electroweak theory, obtained by the insertion of the complete energy-momentum tensor (T) on 2-point functions of neutral gauge currents (VV'). The vertex defines the leading contribution to the effective action which accounts for the conformal anomaly and related interaction between the Standard Model and gravity. The energy-momentum tensor is derived from the curved spacetime Lagrangian in the linearized gravitational limit, and with the inclusion of the term of improvement of a conformally coupled Higgs sector. As in the previous cases of QED and QCD, we find that the conformal anomaly induces an effective massless scalar interaction between gravity and the neutral currents in each gauge invariant component of the vertex. This is described by the exchange of an anomaly pole. We show that for a spontaneously broken theory the anomaly can be entirely attributed to the poles only for a conformally coupled Higgs scalar. In the exchange of a graviton, the trace part of the corresponding interaction can be interpreted as due to an effective dilaton, using a local version of the effective action. We discuss the implications of the anomalous Ward identity for the TVV' correlator for the structure of the gauge/gauge/effective dilaton vertex in the effective action. The analogy between these effective interactions and those related to the radion in theories with large extra dimensionion in theories with large extra dimensions is pointed out.

199

Renormalization of non-abelian gauge theories in curved space-time

International Nuclear Information System (INIS)

We use indirect, renormalization group arguments to calculate the gravitational counterterms needed to renormalize an interacting non-abelian gauge theory in curved space-time. This method makes it straightforward to calculate terms in the trace anomaly which first appear at high order in the coupling constant, some of which would need a 4-loop calculation to find directly. The role of gauge invariance in the theory is considered, and we discuss briefly the effect of using coordinate-dependent gauge-fixing terms. We conclude by suggesting possible applications of this work to models of the very early universe

200

Path integral for gauge theories with fermions

International Nuclear Information System (INIS)

The index theorem indicates that a naive unitary transformation of basis vectors for fermions interacting with gauge fields is not allowed in general. On the basis of this observation, it was previously shown that the path integral measure of a gauge invariant fermion theory is transformed non-trivially under the chiral transformation, and thus leading to a simple derivation of ''anomalous'' chiral Ward-Takahashi identities. We here clarify some of the technical aspects associated with the discussion. It is shown that the Jacobian factor in the path integral measure, which corresponds to the Adler-Bell-Jackiw anomaly, is independent of any smooth regularization procedure of large eigenvalues of D in Euclidean theory; this property holds in any even dimensional space-time and also for the gravitational anomaly. The appearance of the anomaly and its connection with the index theorem are thus related to the fact that the primary importance is attached to the Lorentz covariant ''energy'' operator D and that D and ?5 do not commute. The abnormal behavior of the path integral measure at the zero-frequency sector in the presence of instantons and its connection with spontaneous symmetry breaking is also clarified. We comment on several other problems associated with the anomaly and on the Pauli-Villars regularization method. (author)

201

Anomaly Constraints on Monopoles and Dyons

Fermions with magnetic charges can contribute to anomalies. We derive the axial anomaly and gauge anomalies for monopoles and dyons, and find eight new gauge anomaly cancelation conditions in a general theory with both electric and magnetic charges. As a byproduct we also extend the Zwanziger two-potential formalism to include the theta parameter, and elaborate on the condition for CP invariance in theories with fermionic dyons.

Csaki, Csaba; Shirman, Yuri; 10.1103/PhysRevD.81.125028

2010-01-01

202

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

203

Models of inflation based on axions, which owe their popularity to the robustness against UV corrections, have also a very distinct class of signatures. The relevant interactions of the axion are a non-perturbative oscillating contribution to the potential and a shift-symmetric coupling to gauge fields. We review how these couplings affect the cosmological perturbations via a unified study based on the in-in formalism. We then note that, when the inflaton coupling to gauge fields is high enough to lead to interesting observational results, the backreaction of the produced gauge quanta on the inflaton dynamics becomes relevant during the final stage of inflation, and prolongs its duration by about 10 e-foldings. We extend existing results on gravity wave production in these models to account for this late inflationary phase. The strong backreaction phase results in an enhancement of the gravity wave signal at the interferometer scales. As a consequence, the signal is potentially observable at Advanced LIGO/VIR...

Barnaby, Neil; Peloso, Marco

2011-01-01

204

Intersecting orbifold planes and local anomaly cancellation in M-theory

International Nuclear Information System (INIS)

A systematic program is developed for analyzing and canceling local anomalies on networks of intersecting orbifold planes in the context of M-theory. Through a delicate balance of factors, it is discovered that local anomaly matching on the lower-dimensional intersection of two orbifold planes may require twisted matter on those planes which do not conventionally support an anomaly (such as odd-dimensional planes). In this way, gravitational anomalies can, in principle, tell us about (twisted) gauge groups on subspaces which are not necessarily ten-, six- or two-dimensional. An example is worked out for the case of an ((S1)/Z2)) x ((T4)/Z2)) orbifold and possible implications for four-dimensional physics are speculated on

205

SST Anomalies + Wind Anomalies

Sea surface temperature (SST) anomalies and sea surface wind anomalies show the development of the 2002-2003 El Nino based on data from NASAs Aqua and QuikSCAT spacecraft. The wind data has been processed using the Variational Analysis Method (VAM).

Shirah, Greg; Allen, Jesse; Adamec, David

2003-02-03

206

Some remarks are made about free anomaly groups in gauged WZW models. Considering a quite general action, anomaly cancellation is analyzed. The possibility of gauging left and right sectors independently in some cases is remarked. In particular Toda theories can be seen as such a kind of models.

Lugo, A R

1992-01-01

207

Scalar fields superdense gravitating systems

Solutions for scalar fields superdense gravitating systems of flat, open and closed type obtained in the frame of gauge theories of gravitation are discussed. Properties of these systems in dependence on parameter $\\beta$ and initial conditions are analyzed.

Minkevich, A V; Vasilevski, Y G; Vasilevski, Yu. G.

2003-01-01

208

Geometry and anomalies in superconnection space

International Nuclear Information System (INIS)

Using the concepts of gauge and supersymmetry orbits in superconnection space we give a geometrical derivation of the consistency condition for both gauge and supersymmetry anomalies. A relationship between supersymmetry anomalies in different approaches is established. An application is studied. (orig.)

209

Chiral gravity waves and leptogenesis in inflationary models with non-Abelian gauge fields

We present a leptogenesis scenario associated with inflationary models involving non-Abelian gauge fields within the standard model (SM) of particle physics. We show that this class of inflationary models generates intrinsic birefringent gravitational waves that following Alexander, Peskin, and Sheikh-Jabbari [Phys. Rev. Lett. 96, 081301 (2006)], through the gravitational chiral anomaly in the SM, can naturally create a net lepton number density. The CP-violating interaction is produced by tensor fluctuations of the gauge field, while the efficiency of this process is determined by the effective background value of the gauge field. We demonstrate that this mechanism can create the observed value of baryon to photon number density in a natural range of parameters of these models.

Maleknejad, Azadeh

2014-07-01

210

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

211

Anomaly poles as common signatures of chiral and conformal anomalies

International Nuclear Information System (INIS)

One feature of the chiral anomaly, analyzed in a perturbative framework, is the appearance of massless poles which account for it. They are identified by a spectral analysis of the anomaly graph and are usually interpreted as being of an infrared origin. Recent investigations show that their presence is not just confined in the infrared, but that they appear in the effective action under the most general kinematical conditions, even if they decouple in the infrared. Further studies reveal that they are responsible for the non-unitary behaviour of these theories in the ultraviolet (UV) region. We extend this analysis to the case of the conformal anomaly, showing that the effective action describing the interaction of gauge fields with gravity is characterized by anomaly poles that give the entire anomaly and are decoupled in the infrared (IR), in complete analogy with the chiral case. This complements a related analysis by Giannotti and Mottola on the trace anomaly in gravity, in which an anomaly pole has been identified in the corresponding correlator using dispersion theory in the IR. Our extension is based on an exact computation of the off-shell correlation function involving an energy-momentum tensor and two vector currents (the gauge-gauge-graviton vertex) which is responsible for the appearance of the anomaly.

212

Digital Repository Infrastructure Vision for European Research (DRIVER)

The inclusion of a flat metric tensor in gravitation permits the formulation of a gravitational stress-energy tensor and the formal derivation of general relativity from a linear theory in flat spacetime. Building on the works of Kraichnan and Deser, we present such a derivation using universal coupling and gauge invariance. Next we slightly weaken the assumptions of universal coupling and gauge invariance, obtaining a larger ``slightly bimetric'' class of theories, in ...

Pitts, J. Brian; Schieve, W. C.

2001-01-01

213

What's wrong with anomalous chiral gauge theory?

International Nuclear Information System (INIS)

It is argued on general ground and demonstrated in the particular example of the Chiral Schwinger Model that there is nothing wrong with apparently anomalous chiral gauge theory. If quantised correctly, there should be no gauge anomaly and chiral gauge theory should be renormalisable and unitary, even in higher dimensions and with non-Abelian gauge groups. Furthermore, it is claimed that mass terms for gauge bosons and chiral fermions can be generated without spoiling the gauge invariance. 19 refs

214

The six-dimensional gravitational and gauge anomaly-free E 6 × E 7 × U(1) theory requires change of the three-form field strength H by an additional Lorentz Chern-Simons three-form. The action with this modification by Randjbar-Daemi, Salam, Sezgin and Strathdee is supersymmetrized to linear order in the Noether expansion parameter ? without H. The equations of motion to this order are satisfied by monopole compactifications.

Kee Han, Seung; Kim, Jae Kwan; Koh, I. G.; Tanii, Yoshiaki

1986-09-01

215

International Nuclear Information System (INIS)

The antifield formalism adapted in the exact renormalization group is found to be useful for describing a system with some symmetry, especially the gauge symmetry. In the formalism, the vanishing of the quantum master operator implies the presence of a symmetry. The QM operator satisfies a simple algebraic relation that will be shown to be related to the Wess-Zumino condition for anomalies. We also explain how an anomaly contributes to the QM operator. (author)

216

International Nuclear Information System (INIS)

We develop a systematic method to construct the gauged BRST symmetry for any theory. In this framework, it results as the combination of two basic symmetries of the gauge-fixed theory one considers: the BRST symmetry and the ghost number symmetry, this later being promoted to a local one. From this, we can derive a general relation between the BRST and the ghost number Noether currents. We then take advantage of the present method to elaborate a geometrical algorithm leading to the obtention of the gauged BRST symmetry for a large class of theories, in arbitrary dimensions of space. These involve systems of antisymmetric tensor gauge fields of arbitrary rank, eventually coupled to gravity. This algorithm allows us to derive algebraically the expressions for the possible consistent anomalies of the BRST Noether current algebras; various examples are explicitely discussed. The gauged BRST symmetry for the free bosonic string is also constructed and used to exhibit the link between the trace anomaly and the nilpotency anomaly of the BRST charge operator. In particular, when the Beltrami parametrization is introduced, we show that the corresponding BRST symmetry can be gauged in a way compatible with the holomorphic factorization. A further use of Ward-Slavnov identities constraining the BRST and ghost number current algebra allows us to recover the well-known local counterterm necessary, at the one-loop level, to render the BRST

217

How to test gravitation theories by means of gravitational-wave measurements

Gravitational-wave experiments are a potentially powerful tool for testing gravitation theories. Most theories in the literature predict rather different polarization properties for gravitational waves than are predicted by general relativity; and many theories predict anomalies in the propagation speeds of gravitational waves.

Thorne, K. S.

1974-01-01

218

Digital Repository Infrastructure Vision for European Research (DRIVER)

We discuss the definitions of standard clocks in theories of gravitation. These definitions are motivated by the invariance of actions under different gauge symmetries. We contrast the definition of a standard Weyl clock with that of a clock in general relativity and argue that the historical criticisms of theories based on non-metric compatible connections by Einstein, Pauli and others must be considered in the context of Weyl's original gauge symmetry. We argue that standa...

Teyssandier, Pierre; Tucker, Robin W.

1995-01-01

219

Energy Technology Data Exchange (ETDEWEB)

The six-dimensional gravitational and gauge anomaly-free E/sub 6/xE/sub 7/xU(1) theory requires change of the three-form field strength H by an additional Lorentz Chern-Simons three-form. The action with this modification by Randjbar-Daemi, Salam, Sezgin and Strathdee is supersymmetrized to linear order in the Noether expansion parameter ..gamma.. without H. The equations of motion to this order are satisfied by monopole compactifications.

Han, S.K.; Kim, J.K.; Koh, I.G.; Tanii, Yoshiaki

1986-09-11

220

Higher derivative regularization and chiral anomaly

International Nuclear Information System (INIS)

A higher derivative regularization which automatically leads to the consistent chiral anomaly is analyzed in detail. It explicitly breaks all the local gauge symmetry but preserves global chiral symmetry and leads to the chirally symmetric consistent anomaly. This regularization thus clarifies the physics content contained in the consistent anomaly. We also briefly comment on the application of this higher derivative regularization to massless QED. (author)

221

Tumbling and the strong anomaly

International Nuclear Information System (INIS)

A non-trivial strong anomaly is shown to trigger the tumbling of gauge theories and to help in determining the possible pattern of consequent symmetry breakings. Solutions with partial conservation of chirality can be exhibited even for QCD-like theories. (orig.)

222

Regularized determinants and non-perturbative definition of chiral anomalies

International Nuclear Information System (INIS)

We develop a non-perturbative regularization scheme for fermions interacting with external gauge fields. It is used to obtain the axial anomalies in theories with (classical) global and local axial-vector symmetries. The main result is that in the latter case, this regularization automatically produces the consistent anomaly, provided the cut-off operator is vector gauge covariant. (orig.)

223

Supersymmetry: Kaluza-Klein theory, anomalies, and superstrings

International Nuclear Information System (INIS)

Progress in the search for a unified theory of elementary particles is reviewed. The supersymmetrical Kaluza-Klein theories are described: 11-, 10-, and 6-dimensional models of supergravity. The methods of spontaneous compactification, with whose help the four-dimensional theories are obtained, are described. The properties of the massless sector: zero modes in the Kaluza-Klein theories: and the question of the stability of vacuum solutions are discussed. An important criterion for the selection of a self-consistent theory is the absence of anomalies. The basic formulas for multidimensional chiral and gravitational anomalies are presented. The mechanism of the cancellation of the anomaly for Green and Schwarz's 10-dimensional effective field theory of superstrings with the gauge groups SO(32) and E8 x E8 is described. The basic concepts and the results of the theory of superstrings are presented. This theory has no divergences and is at the present time a very attractive candidate for a unified theory of elementary particles

224

Refining the anomaly consistency condition

In the extended antifield formalism, a quantum BRST differential for anomalous gauge theories is constructed. Local BRST cohomological classes are characterized, besides the form degree and the ghost number, by the length of their descents and of their lifts, and this both in the standard and the extended antifield formalism. It is shown that during the BRST invariant renormalization of a local BRST cohomological class, the anomaly that can appear is constrained to be a local BRST cohomological class with a shorter descent and a longer lift than the given class. As an application of both results, a simple approach to the Adler-Bardeen theorem for the non abelian gauge anomaly is proposed. It applies independently of the gauge fixing, of power counting restrictions and does not rely on the use of the Callan-Symanzik equation.

Barnich, G

2000-01-01

225

Refining the anomaly consistency condition

In the extended antifield formalism, a quantum BRST differential for anomalous gauge theories is constructed. Local BRST cohomological classes are characterized, in addition to the form degree and the ghost number, by the length of their descents and of their lifts, and this both in the standard and the extended antifield formalism. It is shown that during the BRST invariant renormalization of a local BRST cohomological class, the anomaly that can appear is constrained to be a local BRST cohomological class with a shorter descent and a longer lift than the given class. As an application of both results, a simple approach to the Adler-Bardeen theorem for the non-Abelian gauge anomaly is proposed. It applies independently of the gauge fixing, of power counting restrictions, and does not rely on the use of the Callan-Symanzik equation.

Barnich, Glenn

2000-08-01

226

Gauge Model Based on Group G × SU(2)

International Nuclear Information System (INIS)

We present a model of gauge theory based on the symmetry group G × SU(2) where G is the gravitational gauge group and SU(2) is the internal group of symmetry. We employ the spacetime of four-dimensional Minkowski, endowed with spherical coordinates, and describe the gauge fields by gauge potentials. The corresponding strength field tensors are calculated and the field equations are written. A solution of these equations is obtained for the case that the gauge potentials have a particular form with spherical symmetry. The solution for the gravitational potentials induces a metric of Schwarzschild type on the gravitational gauge group space

227

Gauge model based on group G x SU(2)

International Nuclear Information System (INIS)

We present a model of gauge theory based on the symmetry group G x SU(2) where G is the gravitational gauge group and SU(2) is the internal group of symmetry. We employ the spacetime of four-dimensional Minkowski, endowed with spherical coordinates, and describe the gauge fields by gauge potentials. The corresponding strength field tensors are calculated and the field equations are written. A solution of these equations is obtained for the case that the gauge potentials have a particular form with spherical symmetry. The solution for the gravitational potentials induces a metric of Schwarzschild type on the gravitational gauge group space. (authors)

228

The Gauge/String Correspondence Towards Realistic Gauge Theories

This report presents some studies of the gauge/string theory correspondence, a deep relation that is possible to establish between quantum field theories with local gauge symmetry and superstring theories including gravity. In its original version, known as AdS/CFT duality, the correspondence involves N=4 Super Yang-Mills theory in four space-time dimensions, which is a superconformal theory with a high degree of supersymmetry, thus very far from describing the physical world. We explore extensions of the correspondence towards less supersymmetric and non-conformal gauge theories. Specifically, we study gauge theories in three and four dimensions, with eight or four preserved supersymmetries and exhibiting a scale anomaly, by means of supergravity solutions describing D-brane configurations of type II string theory. We show how relevant information on these gauge theories can be extracted from the dual classical solutions, both at the perturbative (e.g. running coupling constant, chiral anomaly) and non-pertu...

Imeroni, E

2003-01-01

229

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

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

230

Gaugino-Assisted Anomaly Mediation

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...

Kaplan, D E; Kaplan, David Elazzar; Kribs, Graham D.

2000-01-01

231

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

232

Astrometric solar system anomalies

Energy Technology Data Exchange (ETDEWEB)

There are at least four unexplained anomalies connected with astrometric data. perhaps the most disturbing is the fact that when a spacecraft on a flyby trajectory approaches the Earth within 2000 km or less, it often experiences a change in total orbital energy per unit mass. next, a secular change in the astronomical unit AU is definitely a concern. It is increasing by about 15 cm yr{sup -1}. The other two anomalies are perhaps less disturbing because of known sources of nongravitational acceleration. The first is an apparent slowing of the two Pioneer spacecraft as they exit the solar system in opposite directions. Some astronomers and physicists are convinced this effect is of concern, but many others are convinced it is produced by a nearly identical thermal emission from both spacecraft, in a direction away from the Sun, thereby producing acceleration toward the Sun. The fourth anomaly is a measured increase in the eccentricity of the Moon's orbit. Here again, an increase is expected from tidal friction in both the Earth and Moon. However, there is a reported unexplained increase that is significant at the three-sigma level. It is produent to suspect that all four anomalies have mundane explanations, or that one or more anomalies are a result of systematic error. Yet they might eventually be explained by new physics. For example, a slightly modified theory of gravitation is not ruled out, perhaps analogous to Einstein's 1916 explanation for the excess precession of Mercury's perihelion.

Nieto, Michael Martin [Los Alamos National Laboratory; Anderson, John D [PROPULSION LABORATORY

2009-01-01

233

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.

Viktor T. Toth

2010-09-01

234

Galilean Theories of Gravitation

Digital Repository Infrastructure Vision for European Research (DRIVER)

A generalization of Newtonian gravitation theory is obtained by a suitable limiting procedure from the ADM action of general relativity coupled to a mass-point. Three particular theories are discussed and it is found that two of them are invariant under an extended Galilei gauge group.

Pietri, R.; Lusanna, L.; Pauri, M.

1992-01-01

235

Calculation of the commutator anomaly

International Nuclear Information System (INIS)

It is well-known that, for the non-Abelian gauge theory coupled to the chiral fermions, which is described by a Lagrangian, the anomaly of the non-Abelian current is given by the descent form of the Chern-Simon five form; D*Ja = (-1/24?2)tr[d(AdA + 1/2A3)], where A = A?dx? = -itaA?adx?. Recently, Faddeev argued that, for such an anomalous system, the gauge symmetry would be represented in a generalized sense of projective representation; V(g1)V(g2)?(A) = exp[i?2(g1, g2; A)] X V(g1g2)?(A), where ?(A) is the wave functional and the phase factor ?2 depends on both the group elements and the gauge field configuration A. Here, it is convenient to consider the infinitesimal version of the above argument. The generator of infinitesimal gauge transformation in the temporal gauge A0 = 0 is given by Ga(x) = ?iEia + gfabcAibEic - g?-bar?0ta?, and the infinitesimal form of the previous product rule can be written as the equal time commutation relation; [Ga(x), Gb(y)] = ifabcGc(x)?3(x-y) + ab(x,y,A), where is related to ?2. In this equation, the first term is what is expected as the normal commutation relation of the generator, while the second term is an anomaly, which is designated here as the commutator anomaly. Then the present study concentrates on operations to determine the anomaly term. (Nogami, A.)

236

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

237

The implications and accuracy of anomaly maps produced using Magsat data on the scalar and vector magnetic field of the earth are discussed. Comparisons have been made between the satellite maps and aeromagnetic survey maps, showing smoother data from the satellite maps and larger anomalies in the aircraft data. The maps are being applied to characterize the structure and tectonics of the underlying regions. Investigations are still needed regarding the directions of magnetization within the crust and to generate further correlations between anomaly features and large scale geological structures. Furthermore, an increased data base is recommended for the Pacific Ocean basin in order to develop a better starting model for Pacific tectonic movements. The Pacific basin was large farther backwards in time and subduction zones surround the basin, thereby causing difficulties for describing the complex break-up scenario for Gondwanaland.

Harrison, C. G. A.

1983-04-01

238

Directory of Open Access Journals (Sweden)

Full Text Available Congenital anomalies in conjunction with intrauterine growth restriction account for 50-60% of fetal mortality. This article describes major birth defects by systems; most can be diagnosed by ultrasound while others cannot. Some anomalies develop later in pregnancy and in some cases sonographic examination may suggest the presence of a nonexistent abnormality. Incidence, etiology and risk factors of congenital malformations are described, as well as the importance and characteristics of prenatal diagnosis and prevention through folic acid supplementation in the diet.

Bernardita Donoso Bernales

2012-10-01

239

Gauge independent effective gauge fields

The problem of gauge independent definition of the effective gauge field is considered. The Slavnov identities corresponding to a system of interacting quantum gauge and classical matter fields, playing the role of a measuring device, are obtained. With their help, in the case of power-counting renormalizable theories, gauge independence of the effective device action is proved in the low-energy limit, which allows to introduce the gauge independent notion of the effective gauge field.

Kazakov, K A; Kazakov, Kirill. A.; Pronin, Petr. I.

2000-01-01

240

International Nuclear Information System (INIS)

The mathematics of gauge fields and some related concepts are discussed: some corrections on the principal fiber bundles emphasize the idea that the present formulation of continuum theories is incomplete. The main ingredients used through the construction of the renormalized perturbation series are then described: the Faddeev Popov argument, and the Faddeev Popov Lagrangian; the Slavnov symmetry and the nature of the Faddeev Popov ghost fields; the Slavnov identity, with an obstruction: the Adler Bardeen anomaly, and its generalization to the local cohomology of the gauge Lie algebra. Some smooth classical configurations of gauge fields which ought to play a prominent role in the evaluation of the functional integral describing the theory are also reviewed

241

Toward a gauge field theory of gravity.

Joint use of two differential identities (Bianchi and Freud) permits a gauge field theory of gravity in which the gravitational energy is localizable. The theory is compatible with quantum mechanics and is experimentally viable.

Yilmaz, H.

242

Phase factors, point-splitting regularisation and chiral anomalies

International Nuclear Information System (INIS)

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.)

243

Gauge field topology and the hadron spectrum

Topologically non-trivial gauge field configurations are an interesting aspect of non-abelian gauge theories. These become particularly important upon quantizing the theory, especially through their effect on the pseudo-scalar spectrum. These effects are closely tied to chiral anomalies and the possibility of CP violation in the strong interactions.

Creutz, Michael

2014-01-01

244

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

245

Gauge structure of vacuum string field theory

International Nuclear Information System (INIS)

We study the gauge structure of vacuum string field theory expanded around the D-brane solution, namely, the gauge transformation and the transversality condition of the massless vector fluctuation mode. We find that the gauge transformation on massless vector field is induced as an anomaly; an infinity multiplied by an infinitesimal factor. The infinity comes from the singularity at the edge of the eigenvalue distribution of the Neumann matrix, while the infinitesimal factor from the violation of the equation of motion of the fluctuation modes due to the regularization for the infinity. However, the transversality condition cannot be obtained even if we take into account the anomaly contribution. (author)

246

Grand unification through gravitational effects

We systematically study the unification of gauge couplings in the presence of (one or more) effective dimension-5 operators cHGG/4MPl, induced into the grand unified theory by gravitational interactions at the Planck scale MPl. These operators alter the usual condition for gauge coupling unification, which can, depending on the Higgs content H and vacuum expectation value, result in unification at scales MX significantly different than naively expected. We find non-supersymmetric models of SU(5) and SO(10) unification, with natural Wilson coefficients c, that easily satisfy the constraints from proton decay. Furthermore, gauge coupling unification at scales as high as the Planck scale seems feasible, possibly hinting at simultaneous unification of gauge and gravitational interactions. In an appendix we work out the group theoretical aspects of this scenario for SU(5) and SO(10) unified groups in detail; this material is also relevant in the analysis of non-universal gaugino masses obtained from supergravity.

Calmet, Xavier; Reeb, David

2009-01-01

247

Torsional Anomalies, Hall Viscosity, and Bulk-boundary Correspondence in Topological 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 parti...

Hughes, Taylor L; Parrikar, Onkar

2013-01-01

248

Yang's pure space equations (C.N. Yang, Phys. Rev. Lett. v.33, p.445 (1974)) generalize Einstein's gravitational equations, while coming from gauge theory. We study these equations from a number of vantage points: summarizing the work done previously, comparing them with the Einstein equations and investigating their properties. In particular, the initial value problem is discussed and a number of results are presented for these equations with common energy-momentum tensors.

Guilfoyle, B S; Guilfoyle, Brendan S.; Nolan, Brien C.

1998-01-01

249

Modern on-shell methods allow us to construct both the classical and quantum S-matrix for a large class of theories, without utilizing knowledge of the interacting Lagrangian. It was recently shown that the same applies for chiral gauge theories, where the constraints from anomaly cancelation can be recast into the tension between unitarity and locality, without any reference to gauge symmetry. In this paper, we give a more detailed exploration, for chiral QED and QCD. We study the rational terms that are mandated by locality, and show that the factorization poles of such terms reveal a new particle in the spectrum, the Green-Schwarz two-from. We further extend the analysis to six-dimensional gravity coupled to chiral matter, including self-dual two-forms for which covariant actions generically do not exist. Despite this, the on-shell methods define the correct quantum S-matrix by demonstrating that locality of the one-loop amplitude requires combination of chiral matter that is consistent with that of anomal...

Chen, Wei-Ming; McGady, David A

2014-01-01

250

Gravitation equations and space-time relativity

Digital Repository Infrastructure Vision for European Research (DRIVER)

In contrast to electrodynamics, Einstein's gravitation equations are not invariant with respect to a wide class of the mapping of field variables which leave equations of motion of test particles in a given coordinate system invariant. It seems obvious enough that just these mappings should play a role of gauge transformations of the variables in differential equations of gravitational field. We consider here in short a gauge-invariant bimetric generalisation of the Einstein...

Verozub, Leonid

2008-01-01

251

The conformal anomaly of k-strings

International Nuclear Information System (INIS)

Simple scaling properties of correlation functions of a confining gauge theory in d-dimensions lead to the conclusion that k-string dynamics is described, in the infrared limit, by a two-dimensional conformal field theory with conformal anomaly c = (d-2)?k/?, where ?k is the k-string tension and ? that of the fundamental representation. This result applies to any gauge theory with stable k-strings. We check it in a 3D Z4 gauge model at finite temperature, where a string effect directly related to c can be clearly identified

252

Riemann geometry of classical gauge field theories

International Nuclear Information System (INIS)

The study of classical gauge field theories is considered from the viewpoint of Riemannian geometry. It is seen that such a theory with an n-parameter gauge group is simply general relativity in a (4n+1)-dimensional Riemannian spacetime, Msup(4+n). Classical gauge theories can be based on an equivalence principle generalised to Msup(4+n), in the same way that Einstein gravitation is based on an equivalence principle in M4. (A.W.)

253

Tensor gauge condition and tensor field decomposition

Digital Repository Infrastructure Vision for European Research (DRIVER)

We discuss various proposals of separating a tensor field into pure-gauge and gauge-invariant components. Such tensor field decomposition is intimately related to the effort of identifying the real gravitational degrees of freedom out of the metric tensor in Einstein's general relativity. We show that, as for a vector field, the tensor field decomposition has exact correspondence to, and can be derived from, the gauge-fixing approach. The complication for the tensor field, h...

Chen, Xiang-song; Zhu, Ben-chao

2011-01-01

254

International Nuclear Information System (INIS)

This invention relates to vacuum gauges, particularly of the type known as Penning gauges, which are cold cathode ionisation gauges, in which a magnetic field is used to lengthen the electron path and thereby increase the number of ions produced. (author)

255

Cohomology for covariant anomalies

International Nuclear Information System (INIS)

We study a new cohomology approach to the covariant anomalies in detail. A set of differential forms is constructed from descent-like 'sidestepping' equations. From this set, we can derive the covariant anomalies including the commutator anomaly as well as the current anomaly with correct normalizations. We also discuss the relation to the conventional set of differential forms for the consistent anomalies. (author)

256

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

257

The Anomaly Structure of Regularized Supergravity

On-shell Pauli-Villars regularization of the one-loop divergences of supergravity theories is used to study the anomaly structure of supergravity and the cancellation of field theory anomalies under a $U(1)$ gauge transformation and under the T-duality group of modular transformations in effective supergravity theories with three K\\"ahler moduli $T^i$ obtained from orbifold compactification of the weakly coupled heterotic string. This procedure requires constraints on the chiral matter representations of the gauge group that are consistent with known results from orbifold compactifications. Pauli-Villars regulator fields allow for the cancellation of all quadratic and logarithmic divergences, as well as most linear divergences. If all linear divergences were canceled, the theory would be anomaly free, with noninvariance of the action arising only from Pauli-Villars masses. However there are linear divergences associated with nonrenormalizable gravitino/gaugino interactions that cannot be canceled by PV fields...

Butter, Daniel

2014-01-01

258

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.)

259

The Nonlinear Essence of Gravitational Waves

A critical review of gravitational wave theory is made. It is pointed out that the usual linear approach to the gravitational wave theory is neither conceptually consistent nor mathematically justified. Relying upon that analysis it is then argued that -- analogously to a Yang-Mills propagating field, which must be nonlinear to carry its gauge charge -- a gravitational wave must necessarily be nonlinear to transport its own charge -- that is, energy-momentum.

Aldrovandi, R; Vu, K H

2007-01-01

260

Hidden local symmetries from flavour anomalies of QCD

International Nuclear Information System (INIS)

Making use of the generating functional of the non-Abelian flavour anomalies of QCD, a gauge invariant phenomenological Lagrangian of pseudoscalar and vector mesons was constructed, which is equivalent to the extended Wess-Zumino Lagrangian in the low energy approximation. The gauge kinetic term of the hidden local symmetry is necessarily present and the gauge coupling constant is determined by the equivalence. (author)

261

A lattice formulation of chiral gauge theories

Energy Technology Data Exchange (ETDEWEB)

The authors present a method for formulating gauge theories of chiral fermions in lattice field theory. The method makes use of a Wilson mass to remove doublers. Gauge invariance is then restored by modifying the theory in two ways: the magnitude of the fermion determinant is replaced with the square root of the determinant for a fermion with vector-like couplings to the gauge field; a double limit is taken in which the lattice spacing associated with the fermion field is taken to zero before the lattice spacing associated with the gauge field. The method applies only to theories whose fermions are in an anomaly-free representation of the gauge group. They also present a related technique for computing matrix elements of operators involving fermion fields. Although the analyses of these methods are couched in weak-coupling perturbation theory, it is argued that computational prescriptions are gauge invariant in the presence of a nonperturbative gauge-field configuration.

Bodwin, G.T. [Argonne National Lab., IL (United States). High Energy Physics Div.

1995-12-01

262

Gravitation and inertia; a rearrangement of vacuum in gravity

Digital Repository Infrastructure Vision for European Research (DRIVER)

We address the gravitation and inertia in the framework of 'general gauge principle', which accounts for 'gravitation gauge group' generated by hidden local internal symmetry implemented on the flat space. We connect this group to nonlinear realization of the Lie group of 'distortion' of local internal properties of six-dimensional flat space, which is assumed as a toy model underlying four-dimensional Minkowski space. The agreement between proposed gravitational theory and ...

Ter-kazarian, Gagik

2010-01-01

263

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

264

We present a UV complete model with a gauged flavor symmetry which approximately realizes holomorphic Minimal Flavor Violation (MFV) in R-parity violating (RPV) supersymmetry. Previous work has shown that imposing MFV as an ansatz easily evades direct constraints and has interesting collider phenomenology. The model in this work spontaneously breaks the flavor symmetry and features the minimum "exotic" field content needed to cancel anomalies. The flavor gauge bosons exhibit an inverted hierarchy so that those associated with the third generation are the lightest. This allows low energy flavor constraints to be easily satisfied and leaves open the possibility of flavor gauge bosons accessible at the LHC. The usual MSSM RPV operators are all forbidden by the new gauge symmetry, but the model allows a purely "exotic" operator which violates both R-parity and baryon number. Since the exotic fields mix with MSSM-like right handed quarks, diagonalizing the full mass matrix after flavor-breaking transforms this ope...

Krnjaic, Gordan

2013-01-01

265

Quaternion gauge theory of dyonic fields

International Nuclear Information System (INIS)

Outlining the idea of quaternion non-Abelian gauge formalism and that of the structural symmetry between generalized fields of dyons and gravito-dyons, it is shown that this formulation characterizes the Abelian and non-Abelian structure of dyons in terms of pure real and imaginary unit quaternions. Extending this formalism to the case of gravito-dyons it has been shown that pure imaginary unit quaternions advocate the curvature in the theory of gravito-dyons and hence the SL(2,c) gauge group of gravitation plays the same role as that of SU(2) gauge group does in non-Abelian gauge theory. Furthermore, we have unified the theories of electromagnetism and gravitation in terms of single parameter ? by means of quaternion-gauge formalism and the corresponding field equations have also been derived in a unique and consistent way. (author)

266

Gauge-Fixing and Residual Symmetries in Gauge/Gravity Theories with Extra Dimensions

Digital Repository Infrastructure Vision for European Research (DRIVER)

We study compactified pure gauge/gravitational theories with gauge-fixing terms and show that these theories possess quantum mechanical SUSY-like symmetries between unphysical degrees of freedom. These residual symmetries are global symmetries and generated by quantum mechanical N=2 supercharges. Also, we establish 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 t...

Lim, C. S.; Nagasawa, Tomoaki; Ohya, Satoshi; Sakamoto, Kazuki; Sakamoto, Makoto

2008-01-01

267

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)

268

Gravitational wave detector response in terms of spacetime Riemann curvature

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

269

Axial anomalies of Lifshitz fermions

We compute the axial anomaly of a Lifshitz fermion theory with anisotropic scaling z=3 which is minimally coupled to geometry in 3+1 space-time dimensions. We find that the result is identical to the relativistic case using path integral methods. An independent verification is provided by showing with spectral methods that the eta-invariant of the Dirac and Lifshitz fermion operators in three dimensions are equal. Thus, by the integrated form of the anomaly, the index of the Dirac operator still accounts for the possible breakdown of chiral symmetry in non-relativistic theories of gravity. We apply this framework to the recently constructed gravitational instanton backgrounds of Horava-Lifshitz theory and find that the index is non-zero provided that the space-time foliation admits leaves with harmonic spinors. Using Hitchin's construction of harmonic spinors on Berger spheres, we obtain explicit results for the index of the fermion operator on all such gravitational instanton backgrounds with SU(2)xU(1) isom...

Bakas, Ioannis

2011-01-01

270

Regularisation of Chiral Gauge Theories

This article gives a review of the topic of regularising chiral gauge theories and is aimed at a general audience. It begins by clarifying the meaning of chirality and goes on to discussing chiral projections in field theory, parity violation and the distinction between vector and chiral field theories. It then discusses the standard model of electroweak interactions from the perspective of chirality. It also reviews at length the phenomenon of anomalies in quantum field theories including the intuitive understanding of anomalies based on the Dirac sea picture as given by Nielsen and Ninomiya. It then raises the issue of a non-perturbative and constructive definition of the standard model as well as the importance of such formulations. The second Nielsen-Ninomiya theorem about the impossibility of regularising chiral gauge theories under some general assumptions is also discussed. After a brief review of lattice regularisation of field theories, it discusses the issue of fermions on the lattice with special e...

Hari-Dass, N D

2000-01-01

271

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.)

272

Liouville action in cone gauge

International Nuclear Information System (INIS)

The effective action of the conformally invariant field theory in the curved background space is considered in the light cone gauge. The effective potential in the classical background stress is defined as the Legendre transform of the Liouville action. This potential is tightly connected with the sl(2) current algebra. The series of the covariant differential operators is constructed and the anomalies of their determinants are reduced to this effective potential. 7 refs

273

Anomaly matching for the QCD string

A criterion to be satisfied by a string theory of QCD is formulated in the ultraviolet regime. It arises from the trace anomaly of the QCD stress tensor computed using instantons. It is sensitive to asymptotic freedom. It appears to be related to the trace anomaly of the QCD string. Our current understanding of noncritical strings in physical dimensions is limited, but remarkably, a formal treatment of the bosonic string yields numerical agreement both in magnitude and sign for the gauge group SU(2).

Balakrishna, B S

1993-01-01

274

Axial anomalies of Lifshitz fermions

International Nuclear Information System (INIS)

We compute the axial anomaly of a Lifshitz fermion theory with anisotropic scaling z = 3 which is minimally coupled to geometry in 3+1 space-time dimensions. We find that the result is identical to the relativistic case using path integral methods. An independent verification is provided by showing with spectral methods that the ?-invariant of the Dirac and Lifshitz fermion operators in three dimensions are equal. Thus, by the integrated form of the anomaly, the index of the Dirac operator still accounts for the possible breakdown of chiral symmetry in non-relativistic theories of gravity. We apply this framework to the recently constructed gravitational instanton backgrounds of Horava-Lifshitz theory and find that the index is non-zero provided that the space-time foliation admits leaves with harmonic spinors. Using Hitchin's construction of harmonic spinors on Berger spheres, we obtain explicit results for the index of the fermion operator on all such gravitational instanton backgrounds with SU(2) x U(1) isometry. In contrast to the instantons of Einstein gravity, chiral symmetry breaking becomes possible in the unimodular phase of Horava-Lifshitz theory arising at ? = 1/3 provided that the volume of space is bounded from below by the ratio of the Ricci to Cotton tensor couplings raised to the third power. Some other aspects of the anomalies in non-relativistic quantum field theories are also discussed. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA,2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

275

Standard Model Gauge Couplings from Gauge-Dilatation Symmetry Breaking

It is well known that the self-energy of the gauge bosons is quadratically divergent in the Standard Model when a simple cutoff is imposed. We demonstrate phenomenologically that the quadratic divergences in fact unify. The unification occurs at a surprisingly low scale, GeV. Suppose now that there is a spontaneously broken rotational symmetry between the space-time coordinates and gauge theoretical phases. The symmetry-breaking pattern is such that the gauge bosons arise as the massless Goldstone bosons, whereas the dilatonic mode acts as the massive (Higgs) boson, whose vacuum expectation value determines the gauge couplings. In this case, the quadratic divergences or the tadpoles of the gauge boson self-energy should indeed unify because these divergences need to be cancelled by a universal dilatonic contribution, assuming dynamical symmetry breaking. If there is dynamical symmetry breaking, we are in principle able to calculate the value of the gauge couplings as well as the scale hierarchy . We perform this calculation by adopting a naive quartic symmetry-breaking potential which unfortunately violates local gauge invariance. Using tadpole-cancellation and dilatonic self-energy conditions, the value of is then found to be approximately GeV in the Feynman gauge and GeV in the Landau gauge. The cancellation of an anomaly in the dilaton self-energy requires that the number of fermionic generations equals three. The symmetry-breaking needs to be driven by some other mass-generating mechanism such as electroweak symmetry breaking. Our estimation for is of the correct order if GeV.

Odagiri, Kosuke

2014-09-01

276

We discuss the $U(1)$ gauged version of the 3+1 dimensional Faddeev-Skyrme model supplemented by the Maxwell term. We show that there exist axially symmetric static solutions coupled to the non-integer toroidal flux of magnetic field, which revert to the usual Hopfions ${\\cal A}_{m,n}$ of lower degrees $Q=mn$ in the limit of the gauge coupling constant vanishing. The masses of the static gauged Hopfions are found to be less than the corresponding masses of the usual ungauged solitons ${\\cal A}_{1,1}$ and ${\\cal A}_{2,1}$ respectively, they become lighter as gauge coupling increases. The dependence of the solutions on the gauge coupling is investigated. We find that in the strong coupling regime the gauged Hopfion carries two magnetic fluxes, which are quantized in units of $2\\pi$, carrying $n$ and $m$ quanta respectively. The first flux encircles the position curve and the second one is directed along the symmetry axis. Effective quantization of the field in the gauge sector may allow us to reconsider the usu...

Shnir, Ya

2014-01-01

277

Physical response of light-time gravitational wave detectors

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 array 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 separates into two independent gauge-invariant quantities: a "background" curvature contribution and a "wave" curvature contribution. In this limit the gravitational wave contribution to the detector response reduces to an integral of the gravitational wave contribution of the curvature along the unperturbed photon path between components of the detector. The description presented here provides an unambiguous physical description of what a gravitational wave detector measures and how it operates, a simple means of computing corrections to a detectors response owing to general detector motion, a straightforward way of connecting the results of numerical relativity simulations to gravitational wave detection, and a basis for a general and fully relativistic pulsar timing formula.

Koop, Michael J.; Finn, Lee Samuel

2014-09-01

278

Probing Gravitational Dark Matter

So far all evidences of dark matter (DM) come from astrophysical and cosmological observations, due to the gravitational interactions of DM. It is possible that the true DM particle in the universe joins gravitational interactions only, but nothing else. Such a Gravitational DM (GDM) acts as a weakly interacting massive particle (WIMP), which is conceptually simple and attractive. In this work, we explore this direction by constructing the simplest scalar GDM particle $\\chi_s$. It is a $\\mathbb{Z}_2$ odd singlet under the standard model (SM) gauge group, and naturally joins the unique dimension-4 interaction with Ricci curvature, $\\xi_s\\chi_s^2{\\cal R}$, where $\\xi_s$ is the dimensionless nonminimal coupling. We demonstrate that this gravitational interaction $\\xi_s\\chi_s^2{\\cal R}$, together with Higgs-curvature nonminimal coupling term $\\xi_h H^\\dag H {\\cal R}$, induces effective couplings between $\\chi_s^2$ and SM fields which can account for the observed DM thermal relic abundance. We analyze the annihila...

Ren, Jing

2014-01-01

279

Gauge theory of weak interactions

International Nuclear Information System (INIS)

The central part of the lectures introduces us to the concept of gauge theories, based on the generalization of the symmetry principle to local symmetries. The present volume may be regarded as continuation of volume 2 of this series: ''Quantum mechanics - symmetries'', extending the concepts of continuous symmetry groups to gauge transformations. The application of the gauge principle to weak isospin and hypercharge results in the unified electroweak gauge theory. The concepts of spontaneous symmetry breaking, charged and neutral currents, and mixing angles, are introduced and discussed in broad detail. Many aspects are illustrated with examples selected from current research fields, such as the problem of neutrino mixing with its application to the solar neutrino flux. Additional chapters are concerned with the applications of the electroweak gauge theory to hadronic decays and to the nuclear beta decay, where the presentation is systematically based on the quark model first introduced in volume 2. A separate chapter deals with the phenomenon of CP violation. Only a few years after the formulation of the electroweak gauge theory, it was discovered that the strong interactions are also based on a set of equations that closely resembles those of the unified electroweak theory. This immediately fostered speculations that electroweak and strong interactions could be the low-energy manifestations of a ''grand unified'' gauge theory. The last section of our book contains an extended introduction on the principles underlying the search for such unified theories. We discuss the SU(5) model of Georgi and Glashow, the simplest unified gauge theory, and show how model building is constrained by experimental data. The presentation is broad and self-contained as usual in this series, introducing the student to the new concepts and formal techniques without unnecessary ballast. A detailed derivation of proton decay is presented, and the question of anomaly freedom is discussed. The book concludes with an outlook on supersymmetric unification in the light of recent precision measurements of the electroweak and strong gauge coupling constants. (orig.)

280

Gravitational Model of the Three Elements Theory

Directory of Open Access Journals (Sweden)

Full Text Available The gravitational model of the three elements theory is an alternative theory to dark matter. It uses a modification of Newton’s law in order to explain gravitational mysteries. The results of this model are explanations for the dark matter mysteries, and the Pioneer anomaly. The disparity of the gravitational constant measurements might also be explained. Concerning the Earth flyby anomalies, the theoretical order of magnitude is the same as the experimental one. A very small change of the perihelion advance of the planet orbits is calculated by this model. Meanwhile, this gravitational model is perfectly compatible with restricted relativity and general relativity, and is part of the three element theory, a unifying theory.

Frederic Lassiaille

2012-05-01

281

On the overlap formulation of chiral gauge theory

The overlap formula proposed by Narayanan and Neuberger in chiral gauge theories is examined. The free chiral and Dirac Green's functions are constructed in this formalism. Four dimensional anomalies are calculated and the usual anomaly cancellation for one standard family of quarks and leptons is verified.

Randjbar-Daemi, S; Randjbar-Daemi, S; Strathdee, J

1994-01-01

282

SST Anomalies + Wind Anomalies (with dates)

Sea surface temperature (SST) anomalies and sea surface wind anomalies show the development of the 2002-2003 El Nino based on data from NASAs Aqua and QuikSCAT spacecraft. The wind data has been processed using the Variational Analysis Method (VAM).

Shirah, Greg; Allen, Jesse; Adamec, David

2003-02-03

283

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)

284

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.)

285

Quantum anomalies for generalized Euclidean Taub-NUT metrics

International Nuclear Information System (INIS)

The generalized Taub-NUT metrics exhibit in general gravitational anomalies. This is in contrast with the fact that the original Taub-NUT metric does not exhibit gravitational anomalies, which is a consequence of the fact that it admits Killing-Yano tensors forming Staeckel-Killing tensors as products. We have found that for axial anomalies, interpreted as the index of the Dirac operator, the presence of Killing-Yano tensors is irrelevant. In order to evaluate the axial anomalies, we compute the index of the Dirac operator with the APS boundary condition on balls and on annular domains. The result is an explicit number-theoretic quantity depending on the radii of the domain. This quantity is 0 for metrics close to the original Taub-NUT metric but it does not vanish in general

286

A first look at Weyl anomalies in shape dynamics

International Nuclear Information System (INIS)

One of the more popular objections towards shape dynamics is the suspicion that anomalies in the spatial Weyl symmetry will arise upon quantization. The purpose of this short paper is to establish the tools required for an investigation of the sort of anomalies that can possibly arise. The first step is to adapt to our setting Barnich and Henneaux's formulation of gauge cohomology in the Hamiltonian setting, which serve to decompose the anomaly into a spatial component and time component. The spatial part of the anomaly, i.e., the anomaly in the symmetry algebra itself ([?, ?] ? ? instead of vanishing) is given by a projection of the second ghost cohomology of the Hamiltonian BRST differential associated to ?, modulo spatial derivatives. The temporal part, [?, H] ? ? is given by a different projection of the first ghost cohomology and an extra piece arising from a solution to a functional differential equation. Assuming locality of the gauge cohomology groups involved, this part is always local. Assuming locality for the gauge cohomology groups, using Barnich and Henneaux's results, the classification of Weyl cohomology for higher ghost numbers performed by Boulanger, and following the descent equations, we find a complete characterizations of anomalies in 3+1 dimensions. The spatial part of the anomaly and the first component of the temporal anomaly are always local given these assumptions even in shape dynamics. The part emerging from the solution of the functional differential equations explicitly involves the shape dynamics Hamiltonian, and thus might be non-local. If one restricts this extra piece of the temporal anomaly to be also local, then overall no Weyl anomalies, either temporal or spatial, emerge in the 3+1 case

287

Gauge field theories: various mathematical approaches

This paper presents relevant modern mathematical formulations for (classical) gauge field theories, namely, ordinary differential geometry, noncommutative geometry, and transitive Lie algebroids. They provide rigorous frameworks to describe Yang-Mills-Higgs theories or gravitation theories, and each of them improves the paradigm of gauge field theories. A brief comparison between them is carried out, essentially due to the various notions of connection. However they reveal a compelling common mathematical pattern on which the paper concludes.

Jordan, François; Thierry, Masson

2014-01-01

288

Digital Repository Infrastructure Vision for European Research (DRIVER)

Chiral, conformal and ghost number anomalies are discussed from the viewpoint of the quantum vacuum in Hamiltonian formalism. After introducing the energy cut-off, we derive known anomalies in a new way. We show that the physical origin of the anomalies is the zero point fluctuation of bosonic or fermionic field. We first point out that the chiral U(1) anomaly is understood as the creation of the chirality at the bottom of the regularized Dirac sea in classical electromagnet...

Fumita, Noriyuki

1994-01-01

289

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

290

An explicit example of a tumbling gauge theory

International Nuclear Information System (INIS)

We present a class of two-dimensional models with a non-abelian gauge symmetry. In one model with gauge symmetry is dynamically broken by a fermion bilinear condensate in a 1/n expansion. We discuss the differences between a dynamical and elementary Higgs mechanism due to the presence of a non-abelian axial anomaly. (orig.)

291

Anomalous triple neutral and quartic gauge boson couplings

Energy Technology Data Exchange (ETDEWEB)

At LEP anomalous neutral triple gauge boson couplings are studied in Z{gamma} and ZZ production. Quartic gauge boson couplings are analysed in WW{gamma}, Z{gamma}{gamma}d {nu}{nu}{gamma}{gamma} events. No significant anomalies are found.

Wynhoff, St. E-mail: Stephan.Wynhoff@cern.ch

2003-04-01

292

This model shows the effect of gravitational attraction between two objects, demonstrating that gravitational forces are directly proportional to mass of each body, but inversely proportional to the square of the distance between the bodies. The model may be easily modified to demonstrate Coulomb's Law.

Trout, Charlotte

293

Balloon measurements were made of the far infrared background radiation. The radiometer used and its calibration are discussed. An electromagnetically coupled broadband gravitational antenna is also considered. The proposed antenna design and noise sources in the antenna are reviewed. A comparison is made between interferometric broadband and resonant bar antennas for the detection of gravitational wave pulses.

Weiss, R.; Muehlner, D. J.; Benford, R. L.; Owens, D. K.; Pierre, N. A.; Rosenbluh, M.

1972-01-01

294

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

295

Penner type ensemble for gauge theories revisited

The Penner type ? ensemble for ?-deformed N=2SU(2) gauge theory with two massless flavors arising as a limiting case from the Alday, Gaiotto and Tachikawa conjecture is considered. The partition function can be calculated perturbatively in a saddle-point approximation. A large N limit reproduces the gauge theory partition function expanded in a strong coupling regime, for any ? and beyond tree level, confirming previous results obtained via special geometry and the holomorphic anomaly equation. The leading terms and gap of the gauge theory free energy at the monopole/dyon point follow as a corollary.

Krefl, Daniel

2013-02-01

296

Penner Type Ensemble for Gauge Theories Revisited

The Penner type beta-ensemble for Omega-deformed N=2 SU(2) gauge theory with two massless flavors arising as a limiting case from the AGT conjecture is considered. The partition function can be calculated perturbatively in a saddle-point approximation. A large N limit reproduces the gauge theory partition function expanded in a strong coupling regime, for any beta and beyond tree-level, confirming previous results obtained via special geometry and the holomorphic anomaly equation. The leading terms and gap of the gauge theory free energy at the monopole/dyon point follow as a corollary.

Krefl, Daniel

2012-01-01

297

Composite gauge field models with broken symmetries

We present a generalization of the non-Abelian version of the $CP^{N-1}$ models (also known as Grassmannian models) that involve composite gauge fields to accommodate partial breaking of the non-Abelian gauge symmetry. For this to be possible, in most cases, the constituent fields need to belong to an anomaly free complex representation. Symmetry is broken dynamically for large $N$ primarily by a naturally generated composite scalar which simulates Higgs mechanism. In the example studied in some detail, the gauge group SO(10) gets broken down to subgroups like SU(5) or SU(5)$\\times$U(1).

Balakrishna, B S

1994-01-01

298

Eliminating the chiral anomaly via symplectic embedding approach

The quantization of the chiral Schwinger model $(\\chi QED_{2})$ with one-parameter class Faddeevian regularization is hampered by the chiral anomaly, i.e., the Gauss law commutator exhibits Faddeev's anomaly. To overcome this kind of problem, we propose to eliminate this anomaly by embedding the theory through a new gauge-invariant formalism based on the enlargement of the phase space with the introduction of Wess-Zumino(WZ) fields and the symplectic approach. This process opens up a possibility to formulate different, but dynamically equivalent, gauge invariant versions for the model and also gives a geometrical interpretation to the arbitrariness presents on the BFFT and iterative conversion methods. Further, we observe that the elimination of the chiral anomaly imposes a condition on the chiral parameters present on the original model and on the WZ sector.

Mendes, A C R; Oliveira, W

2009-01-01

299

Topology of gauge theories on compact 4-manifolds

International Nuclear Information System (INIS)

In a gauge theory the topological structure of the group of gauge transformations G can have important consequences. Information is obtained about the topology of G in four dimensions and this is used to study the existence of a global gauge fixing condition. The topological nature of G also allows inequivalent topological sectors to exist and these are discussed in four- and five-dimensional gauge theories. Finally, the topological structure of G imposes constraints on the existence of global anomalies in four-dimensional gauge theories. (author)

300

Deflected anomaly mediation and neutralino dark matter

International Nuclear Information System (INIS)

This is a study of the phenomenology of the neutralino dark matter in the so called deflected anomaly mediation scenario. This scheme is obtained from the minimal anomaly-mediated scenario by introducing a gauge-mediated sector with Nf messenger fields. Unlike the former scheme the latter has no tachyons. We find that the neutralino is still the LSP in a wide region of the parameter space: it is essentially a pure bino in the scenario with Nf=1 while it can also be a pure Higgsino for Nf>1. This is very different from the naive anomaly-mediated scenario which predicts a wino like neutralino. Moreover we do not find any tachyonic scalars in this scheme. After computing the relic density (considering all the possible coannihilations) we find that there are regions in the parameter space with values compatible with the latest WMAP results with no need to consider moduli fields that decay in the early universe

301

302

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

303

Inflationary Baryogenesis in a Model with Gauged Baryon Number

We argue that inflationary dynamics may support a scenario where significant matter-antimatter asymmetry is generated from initially small-scale quantum fluctuations that are subsequently stretched out over large scales. This scenario can be realised in extensions of the Standard Model with an extra gauge symmetry having mixed anomalies with the electroweak gauge symmetry. Inflationary baryogenesis in a model with gauged baryon number is considered in detail.

Barrie, Neil D

2014-01-01

304

Geometrical aspects of chiral anomalies in the overlap

The set of one dimensional lowest energy eigenspaces used to construct the overlap induces a two form on gauge orbit space which is the locally exact curl of Berry's connection. If anomalies do not cancel, examples of two dimensional closed sub-manifolds of orbit space are produced over which the integral of the above two form does not vanish. Based on these observations, a natural definition of covariant currents is obtained, a simple way to calculate chiral anomalies on the lattice is found, and indications for how to construct an ideal regularization of chiral gauge theories are seen to emerge.

Neuberger, H

1999-01-01

305

Composite gauge fields and broken symmetries

International Nuclear Information System (INIS)

A generalization of the non-Abelian version of the CPN-1 models (also known as Grassmannian models) is presented. The generalization helps accommodate a partial breaking of the non-Abelian gauge symmetry. Constituents of the composite gauge fields, in many cases, are naturally constrained to belong to an anomaly-free representation which in turn generates a composite scalar-simulating Higgs mechanism to break the gauge symmetry dynamically for large N. Two cases are studied in detail: one based on the SU(2) gauge group and the other on SO(10). Breakings such as SU(2)?U(1) or SO(10)?SU(5)xU(1) are found feasible. The properties of the composites fields and gauge boson masses are computed by doing a derivative expansion of the large N effective action

306

International Nuclear Information System (INIS)

An introduction to the unified gauge theories of weak and electromagnetic interactions is given. The ingredients of gauge theories and symmetries and conservation laws lead to discussion of local gauge invariance and QED, followed by weak interactions and quantum flavor dynamics. The construction of the standard SU(2)xU(1) model precedes discussion of the unification of weak and electromagnetic interactions and weak neutral current couplings in this model. Presentation of spontaneous symmetry breaking and spontaneous breaking of a local symmetry leads to a spontaneous breaking scheme for the standard SU(2)xU(1) model. Consideration of quarks, leptons, masses and the Cabibbo angles, of the four quark and six quark models and CP violation lead finally to grand unification, followed by discussion of mixing angles in the Georgi-Glashow model, the Higgses of the SU(5) model and proton/ neutron decay in SU(5). (JIW)

307

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.

2013-03-01

308

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

309

Anomalies in non-polynomial closed string field theory

Energy Technology Data Exchange (ETDEWEB)

The complete classical action for the non-polynomial closed string field theory was written down last year by the author and the Kyoto group. It successfully reproduces all closed string tree diagrams, but fails to reproduce modular invariant loop amplitudes. In this paper we show that the classical action is also riddled with gauge anomalies. Thus, the classical action is not really gauge invariant and fails as a quantum theory. The presence of gauge anomalies and the violation of modular invariance appear to be a disaster for the theory. Actually, this is a blessing in disguise. We show that by adding new non-polynomial terms to the action, we can simultaneously eliminate both the gauge anomalies and the modular-violating loop diagrams. We show this explicitly at the one loop level and also for an infinite class of p-puncture, genus-g amplitudes, making use of a series of non-trivial identities. The theory is thus an acceptable quantum theory. We comment on the origin of this strange link between local gauge anomalies and global modular invariance. (orig.).

Kaku, Michio (Institute for Advanced Study, Princeton, NJ (USA))

1990-11-01

310

We analyse scale anomalies in Lifshitz field theories, formulated as the relative cohomology of the scaling operator with respect to foliation preserving diffeomorphisms. We construct a detailed framework that enables us to calculate the anomalies for any number of spatial dimensions, and for any value of the dynamical exponent. We derive selection rules, and establish the anomaly structure in diverse universal sectors. We present the complete cohomologies for various examples in one, two and three space dimensions for several values of the dynamical exponent. Our calculations indicate that all the Lifshitz scale anomalies are trivial descents, called B-type in the terminology of conformal anomalies. However, not all the trivial descents are cohomologically non-trivial. We compare the conformal anomalies to Lifshitz scale anomalies with a dynamical exponent equal to one.

Arav, Igal; Oz, Yaron

2014-01-01

311

Composite gauge bosons of transmuted gauge symmetry

International Nuclear Information System (INIS)

It is shown that effective gauge theories of composite gauge bosons describing the dynamics of composite quarks and leptons can be transmuted from the subcolor gauge theory describing that of subquarks due to the condensation of subquarks and that the equality of effective gauge coupling constants can result as in a grand unified gauge theory. (author)

312

Matter field infinities in axial gauge gravity

International Nuclear Information System (INIS)

The one-loop infinities for scalar, spinor and vector fields due to gravitational interactions are computed in the axial gravity gauge for the Einstein-Hilbert action. The results reveal an axis dependence, in addition to their expected non-renormalisability, which is expected to get progressively worse in higher orders of perturbation theory. This means that gauge equivalences between covariant and non-covariant gauges are impossible in ordinary quantum gravity unless cancellation of infinities occurs through some supersymmetric mechanism or unless a renormalisable conformal version of gravity is adopted. (author)

313

Topological anomalies for Seifert 3-manifolds

We study globally supersymmetric 3d gauge theories on curved manifolds by describing the coupling of 3d topological gauge theories, with both Yang-Mills and Chern-Simons terms in the action, to background topological gravity. In our approach the Seifert condition for manifolds supporting global supersymmetry is elegantly deduced from the topological gravity BRST transformations. A cohomological characterization of the geometrical moduli which affect the partition function is obtained. In the Seifert context Chern-Simons topological (framing) anomaly is BRST trivial. We compute explicitly the corresponding local Wess-Zumino functional. As an application, we obtain the dependence on the Seifert moduli of the partition function of 3d supersymmetric gauge theory on the squashed sphere by solving the anomalous topological Ward identities, in a regularization independent way and without the need of evaluating any functional determinant.

Imbimbo, Camillo

2014-01-01

314

Mansouri-Chang gravitation theory

The gauge theory of gravitation introduced by Mansouri and Chang (1976) is investigated; a symbolic manipulation computer system generates the Mansouri-Chang field equations in various coordinate systems. It is found that all vacuum Einstein spaces are vacuum Mansouri-Chang spaces in four dimensions, though for higher dimensions an Einstein vacuum space is not generally a Mansouri-Chang solution. The possibility that no solutions of the Mansouri-Chang equations are not Einstein vacuum spaces is discussed.

Pavelle, R.

1978-01-01

315

International Nuclear Information System (INIS)

The reinterpretation of the BRS equations of Quantum Field Theory as the Maurer Cartan equation of a classical principal fiber bundle leads to a simple gauge invariant classification of the anomalies in Yang Mills theory and gravity

316

Unification of Gravitational and Electromagnetic Fields in Riemannian Geometry

Digital Repository Infrastructure Vision for European Research (DRIVER)

The gravitational field and the source-free electromagnetic field can be unified preliminarily by the equations in the Riemannian geometry, both are contractions of im and ik, respectively. So it will be equivalent to the Yang gravitational equations. From this we can obtain the Lorentz equations of motion, the first system and second source-free system of Maxwell field equations. This unification can be included in the gauge theory, and the unified gauge group is GL(2,C), w...

Chang, Yi-fang

2009-01-01

317

Topological Defects in Gravitational Theories with Non Linear Lagrangians

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 a...

Audretsch, J.; Economou, A.; Lousto, C. O.

1993-01-01

318

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.

2007-04-01

319

Digital Repository Infrastructure Vision for European Research (DRIVER)

Observers at rest in a stationary spacetime flat at infinity can measure small amounts of rest-mass+internal energies+kinetic energies+pressure energy in a small volume of fluid attached to a local inertial frame. The sum of these small amounts is the total "matter energy" for those observers. The total mass-energy minus the matter energy is the binding gravitational energy. Misner, Thorne and Wheeler evaluated the gravitational energy of a spherically symmetric static spa...

Katz, Joseph

2005-01-01

320

Digital Repository Infrastructure Vision for European Research (DRIVER)

Gravitation has posed a puzzle and a problem for many decades. Attempts to unify it with other fundamental interactions have failed. These problems and puzzles have been underscored by the likes of Witten and Weinberg. We survey this and argue that gravitation has a different character compared to other fundamental interactions - it is an energy distributed over all the elementary particles in the universe. The above puzzle and problem is resolved satisfactorily. These consi...

Sidharth, B. G.

2006-01-01

321

International Nuclear Information System (INIS)

We study the linear post-Newtonian approximation to general relativity known as gravitoelectromagnetism (GEM); in particular, we examine the similarities and differences between GEM and electrodynamics. Notwithstanding some significant differences between them, we find that a special nonstationary metric in GEM can be employed to show explicitly that it is possible to introduce gravitational induction within GEM in close analogy with Faraday's law of induction and Lenz's law in electrodynamics. Some of the physical implications of gravitational induction are briefly discussed

322

Gauge-independent effective gauge fields

Energy Technology Data Exchange (ETDEWEB)

The problem of a gauge-independent definition of the effective gauge field is considered. The Slavnov identities corresponding to a system of interacting quantum gauge and classical matter fields, playing the role of a measuring device, are obtained. With their help, in the case of power-counting renormalizable theories, gauge independence of the effective device action is proved in the low-energy limit. This allows one to introduce a gauge-independent notion of the effective gauge field.

Kazakov, Kirill A. E-mail: kirill@theor.phys.msu.su; Pronin, Petr I. E-mail: petr@theor.phys.msu.su

2000-05-01

323

Chiral, conformal and ghost number anomalies are discussed from the viewpoint of the quantum vacuum in Hamiltonian formalism. After introducing the energy cut-off, we derive known anomalies in a new way. We show that the physical origin of the anomalies is the zero point fluctuation of bosonic or fermionic field. We first point out that the chiral U(1) anomaly is understood as the creation of the chirality at the bottom of the regularized Dirac sea in classical electromagnetic field. In the study of the (1+1) dimensional quantum vacuum of matter field coupled to the gravity, we give a physically intuitive picture of the conformal anomaly. The central charges are evaluated from the vacuum energy. We clarify that the non-Hermitian regularization factor of the vacuum energy is responsible for the ghost number anomaly.

Fumita, N

1994-01-01

324

Chiral, conformal and ghost number anomalies are discussed from the viewpoint of the quantum vacuum in Hamiltonian formalism. After introducing the energy cutoff, we derive known anomalies in a new way. We give an interpretation of the anomalies in connection with the zero-point fluctuation of bosonic or fermionic field. We first point out that the chiral U(1) anomaly is understood as the creation of the chirality at the bottom of the regularized Dirac sea in classical electromagnetic field. In the study of the (1+1)-dimensional quantum vacuum of matter field coupled to the gravity, we give a physically intuitive picture of the conformal anomaly. The central charges are evaluated from the vacuum energy. We clarify that the non-Hermitian regularization factor of the vacuum energy is responsible for the ghost number anomaly.

Fumita, Noriyuki

325

Conformal Anomalies in Hydrodynamics

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

326

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

2011-01-01

327

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

328

The Lense-Thirring effect and the Pioneer anomaly: Solar System tests

Here we report on a 6% test of the general relativistic gravitomagnetic Lense-Thirring effect in the gravitational field of Mars with the Mars Global Surveyor (MGS) spacecraft and on certain features of motion of Uranus, Neptune and Pluto which contradict the hypothesis that the Pioneer anomaly can be caused by some gravitational mechanism.

Iorio, Lorenzo

2008-01-01

329

Geometrical interpretation of a generalized theory of gravitation

International Nuclear Information System (INIS)

The geometrical structure is developed for a theory of gravitation, based on a nonsymmetric metric in a four-dimensional real manifold. The local fiber bundle gauge group is GL(4,R), which contains the (local) homogeneous Lorentz gauge group SO(3,1) of general relativity

330

A new approach to gravitational-wave detection

International Nuclear Information System (INIS)

If one calculates the rates of two clocks in the field of a gravitational wave in the linear approximation, one gets different results in the TT-gauge and the Fermi normal coordinate system. Care should, therefore, be given to use the TT-gauge to make predictions to be compared directly with experimental data

331

International Nuclear Information System (INIS)

A gauge supporting device for measuring say a square tube comprises a pair of rods or guides in tension between a pair of end members, the end members being spaced apart by a compression member or members. The tensioned guides provide planes of reference for measuring devices moved therealong on a carriage. The device is especially useful for making on site dimensional measurements of components, such as irradiated and therefore radioactive components, that cannot readily be transported to an inspection laboratory. (UK)

332

On the fundamental principles of the relativistic theory of gravitation

International Nuclear Information System (INIS)

This paper expounds consistently within the frames of the Special Relativity Theory the fundamental postulates of the Relativistic Theory of Gravitation (RTG) which make it possible to obtain the unique complete system of the equations for gravitational field. Major attention has been paid to the analysis of the gauge group and of the causality principle. Some results related to the evolution of the Friedmann Universe, to gravitational collapse, etc. being the consequences of the RTG equations are also presented. 7 refs

333

(abridged) Gravitationally lensed quasars can be used as powerful cosmological and astrophysical probes. We can (i) infer the Hubble constant based on the time-delay technique, (ii) unveil substructures along the l.o.s. toward distant galaxies, and (iii) compare the shape and the slope of baryons and dark matter distributions in galaxies. To reach these goals, we need high-accuracy astrometry and morphology measurements of the lens. In this work, we first present new astrometry for 11 lenses with measured time delays. Using MCS deconvolution on NIC2 HST images, we reached an astrometric accuracy of about 1-2.5 mas and an accurate shape measurement of the lens galaxy. Second, we combined these measurements with those of 14 other systems to present new mass models of these lenses. This led to the following results: 1) In 4 double-image quasars, we show that the influence of the lens environment on the time delay can easily be quantified and modeled, hence putting these lenses with high priority for time-delay d...

Sluse, D; Magain, P; Courbin, F; Meylan, G

2011-01-01

334

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

International Nuclear Information System (INIS)

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)

335

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

336

Framing Anomaly in the Effective Theory of Fractional Quantum Hall Effect

We consider the geometric part of the effective action for Fractional Quantum Hall Effect (FQHE). It is shown that accounting for the framing anomaly of the quantum Chern-Simons theory is essential to the obtain correct gravitational linear response functions. In the lowest order in gradients the linear response generating functional includes Chern-Simons, Wen-Zee and gravitational Chern- Simons terms. The latter term has a contribution from the framing anomaly which fixes the value of thermal Hall conductivity and contributes to the Hall viscosity of the FQH states on a sphere. We also discuss the effects of the framing anomaly on linear responses for non-Abelian FQH states.

Gromov, Andrey; You, Yizhi; Abanov, Alexander G; Fradkin, Eduardo

2014-01-01

337

Geometrical Superconformal Anomalies

We determine the structure of geometrical superconformal anomalies for N=1 supersymmetric quantum field theories on curved superspace to all orders in h bar. For the massless Wess-Zumino model we show how these anomalies contribute to the local Callan-Symanzik equation which expresses the breakdown of superconformal symmetry in terms of the usual beta and gamma functions.

Erdmenger, J; Erdmenger, Johanna; Rupp, Christian

1998-01-01

338

The purpose of this lesson is to model for students gravitational waves and how they are created. Students will build a simple "Gravitational Wave Demonstrator" using inexpensive materials (plastic wrap, plastic cups, water, food coloring, and rubber bands, marbles). Students should have a basic understanding of waves and be familiar with Einstein's theory of general relativity. The activity can be done either as a teacher demonstration or student activity. This lesson is part of the Cosmic Times teachers guide and is intended to be used in conjunction with the 1993 Cosmic Times Poster.

339

Geodesic-invariant equations of gravitation

Digital Repository Infrastructure Vision for European Research (DRIVER)

Einstein's equations of gravitation are not invariant under geodesic mappings, i. e. under a certain class of mappings of the Christoffel symbols and the metric tensor which leave the geodesic equations in a given coordinate system invariant. A theory in which geodesic mappings play the role of gauge transformations is considered.

Verozub, Leonid V.

2008-01-01

340

One-Loop Pauli-Villars Regularization of Supergravity I: Canonical Gauge Kinetic Energy

Digital Repository Infrastructure Vision for European Research (DRIVER)

It is shown that the one-loop coefficients of on-shell operators of standard supergravity with canonical gauge kinetic energy can be regulated by the introduction of Pauli-Villars chiral and abelian gauge multiplets, subject to a condition on the matter representations of the gauge group. Aspects of the anomaly structure of these theories under global nonlinear symmetries and an anomalous gauge symmetry are discussed.

Gaillard, Mary K.

1998-01-01

341

International Nuclear Information System (INIS)

The experimental results of the Titanium anomalies display a wide variety ranging from -5 to +100 per mil. This wide variation is sought to be explained in terms of the mixture of grains condensed in different types of objects. This may vary from red giants to objects undergoing neutron rich statistical equilibrium with different neutron fluences. It is predicted that the 54Cr anomaly will be correlated with 50Ti, provided the grains condensed out from the oxygen-poor objects, whereas correlation between Ca and Ti anomalies are expected if the grain condensation took place in oxygen-rich objects. Thus correlated anomalies would be the best way to infer the nature of sources contributing to the solar system anomalies

342

D = 26 and Exact Solution to the Conformal-Gauge Two-Dimensional Quantum Gravity

The conformal-gauge two-dimensional quantum gravity is formulated in the framework of the BRS quantization and solved completely in the Heisenberg picture: all n-point Wightman functions are explicitly obtained. The field-equation anomaly is shown to exist as in other gauges, but there is no other subtlety. At the critical dimension D = 26 of the bosonic string, the field-equation anomaly is shown to be absent. However, this result is not equivalent to the statement that the conformal anomaly is proportional to D - 26. The existence of the FP-ghost number current anomaly is seen to be an illusion.

Abe, Mitsuo; Nakanishi, Noboru

343

D=26 and Exact Solution to the Conformal-Gauge Two-Dimensional Quantum Gravity

The conformal-gauge two-dimensional quantum gravity is formulated in the framework of the BRS quantization and solved completely in the Heisenberg picture: All n-point Wightman functions are explicitly obtained. The field-equation anomaly is shown to exist as in other gauges, but there is no other subtlety. At the critical dimension D=26 of the bosonic string, the field-equation anomaly is shown to be absent. However, this result is not equivalent to the statement that the conformal anomaly is proportional to D-26. The existence of the FP-ghost number current anomaly is seen to be an illusion.

Abe, M; Abe, Mitsuo; Nakanishi, Noboru

1999-01-01

344

Anomaly-free constraints in neutrino seesaw models

International Nuclear Information System (INIS)

The implementation of seesaw mechanisms to give mass to neutrinos in the presence of an anomaly-free U(1)X gauge symmetry is discussed in the context of minimal extensions of the standard model. It is shown that type-I and type-III seesaw mechanisms cannot be simultaneously implemented with an anomaly-free local U(1)X, unless the symmetry is a replica of the well-known hypercharge. For combined type-I/II or type-III/II seesaw models it is always possible to find nontrivial anomaly-free charge assignments, which are however tightly constrained, if the new neutral gauge boson is kinematically accessible at LHC. The discovery of the latter and the measurement of its decays into third-generation quarks, as well as its mixing with the standard Z boson, would allow one to discriminate among different seesaw realizations.

345

Supersymmetric gauge theories from string theory

International Nuclear Information System (INIS)

This thesis presents various ways to construct four-dimensional quantum field theories from string theory. In a first part we study the generation of a supersymmetric Yang-Mills theory, coupled to an adjoint chiral superfield, from type IIB string theory on non-compact Calabi-Yau manifolds, with D-branes wrapping certain sub-cycles. Properties of the gauge theory are then mapped to the geometric structure of the Calabi-Yau space. Even if the Calabi-Yau geometry is too complicated to evaluate the geometric integrals explicitly, one can then always use matrix model perturbation theory to calculate the effective superpotential. The second part of this work covers the generation of four-dimensional super-symmetric gauge theories, carrying several important characteristic features of the standard model, from compactifications of eleven-dimensional supergravity on G2-manifolds. If the latter contain conical singularities, chiral fermions are present in the four-dimensional gauge theory, which potentially lead to anomalies. We show that, locally at each singularity, these anomalies are cancelled by the non-invariance of the classical action through a mechanism called 'anomaly inflow'. Unfortunately, no explicit metric of a compact G2-manifold is known. Here we construct families of metrics on compact weak G2-manifolds, which contain two conical singularities. Weak G2-manifolds have properties that are similar to the ones of proper G2-manifolds, and hence the explicit examples might be useful to better understand the generic situation. Finally, we reconsider the relation between eleven-dimensional supergravity and the E8 x E8-heterotic string. This is done by carefully studying the anomalies that appear if the supergravity theory is formulated on a ten-manifold times the interval. Again we find that the anomalies cancel locally at the boundaries of the interval through anomaly inflow, provided one suitably modifies the classical action. (author)

346

Introduction to gauge theories of electroweak interactions

International Nuclear Information System (INIS)

Intended as a lecture for physicists who are not familiar with the sophisticated theoretical models in particle physics. Starting with the standard gauge model of electromagnetic, weak and strong interactions the recent developments of a unified gauge theory of electroweak interactions are shown. Shortcomings in the unitarity problem of the V-A fermi theory of charged intermediate vector bosons. Presented are the spontaneous symmetry breaking in quantum mechanics, the abelian higgs model as an example of a spontaneously broken gauge field theory, the minimal gauge group of electroweak interactions, the fermion mass generation. Further on the anomalies in quantum field theory are discussed and the radiative corrections to the vector boson masses are considered. (H.B.)

347

Low energy gauge unification theory

Because of the problems arising from the fermion unification in the traditional Grand Unified Theory and the mass hierarchy between the 4-dimensional Planck scale and weak scale, we suggest the low energy gauge unification theory with low high-dimensional Planck scale. We discuss the non-supersymmetric SU(5) model on M sup 4 xS sup 1 /Z sub 2 xS sup 1 /Z sub 2 and the supersymmetric SU(5) model on M sup 4 xS sup 1 /(Z sub 2 xZ sub 2 ')xS sup 1 /(Z sub 2 xZ sub 2 ')xS sup 1 /(Z sub 2 xZ sub 2 '). The SU(5) gauge symmetry is broken by the orbifold projection for the zero modes, and the gauge unification is accelerated due to the SU(5) asymmetric light KK states. In our models, we forbid the proton decay, still keep the charge quantization, and automatically solve the fermion mass problem. We also comment on the anomaly cancellation and other possible scenarios for low energy gauge unification.

Li Tian Jun

2002-01-01

348

Titan's gravitational field is inferred from an analysis of archived radio Doppler data for six Cassini flybys. The analysis considers each flyby separately in contrast to the approach of lumping all the data together in a massive inversion. In this way it is possible to gain an improved understanding of the character of each flyby and its usefulness in constraining the gravitational coefficient C22 . Though our analysis is not yet complete and our final determination of C22 could differ from the result we report here by 1 or 2 sigma, we find a best-fit value of C22 equal to (13.21 × 0.17) × 10-6, significantly larger than the value of 10.0 × 10-6 obtained from an inversion of the lumped Cassini data. We also find no determination of the tidal Love number k2. The larger value of C22 implies a moment of inertia factor equal to 0.3819 × 0.0020 and a less differentiated Titan than is suggested by the smaller value. The larger value of C22 is consistent with an undifferentiated model of the satellite. While it is not possible to rule out either value of C22 , we prefer the larger value because its derivation results from a more hands on analysis of the data that extracts the weak hydrostatic signal while revealing the effects of gravity anomalies and unmodeled spacecraft accelerations on each of the six flybys.

Schubert, G.; Anderson, J. D.

2013-12-01

349

International Nuclear Information System (INIS)

ut 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.

350

Earth Gauge is a free environmental information service for broadcast meteorologists in major U.S. media markets, based on the 3-5 day forecast. The service is designed to make it easy to talk about the links between weather and the environment on-air with simple "factoids" and viewer action tips. Teachers or students can browse an index of weather conditions, environmental impacts, and viewer action tips for many locations, organized by city, weather type, or environmental topic. There are also links to additional resources, including fact sheets and special features, imagery, video clips, and others.

351

In this paper the author presents the case of the exchange marriage system to delineate a model of methodological gravitism. Such a model is not a deviation from or alteration to the existing qualitative research approaches. I have adopted culturally specific methodology to investigate spouse selection in line with the Grounded Theory Method. This…

Zaman, Muhammad

2011-01-01

352

International Nuclear Information System (INIS)

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

353

Holonomy Attractor Connecting Spaces of Different Curvature Responsible for ``Anomalies''

In this lecture paper we derive Magic Angle Precession (MAP) from first geometric principles. MAP can arise in situations, where precession is multiply related to spin, linearly by time or distance (dynamic phase, rolling, Gauss law) and transcendentally by the holonomy loop path (geometric phase). With linear spin-precession coupling, gyroscopes can be spun up and down to very high frequencies via low frequency holonomy control induced by external accelerations, which provides for extreme coupling strengths or ``anomalies'' that can be tested by the powerball or gyrotwister device. Geometrically, a gyroscopic manifold with spherical metric is tangentially aligned to a precession wave channel with conic or hyperbolic metric (like the relativistic Thomas precession). Transporting triangular spin/precession vector relations across the tangential boundary of contact with SO(3) Lorentz symmetry, we get extreme vector currents near the attractor fixed points in precession phase space, where spin currents remain intact while crossing the contact boundaries between regions of different curvature signature (-1, 0, +1). The problem can be geometrically solved by considering a curvature invariant triangular condition, which holds on surfaces with different curvature that are in contact and locally parallel. In this case two out of three angles are identical, whereas the third angle is different due to holonomy. If we require that the side length ratio corresponding to these angles are invariant we get a geodesic chaotic attractor, which is a cosine map cos(x)~Mx in parameter space providing for fixed points, limit cycle bifurcations, and singularities. The situation could be quite natural and common in the context of vector currents in curved spacetime and gauge theories. MAP could even be part of the electromagnetic interaction, where the electric charge is the geometric U(1) precession spin current and gauge potential with magnetic effects given by extra rotations under the SO(3). MAP can be extended to a neural network, where the synaptic connection of the holonomy attractor is just the mathematical condition adjusting and bridging spaces with positive (spherical) and negative (hyperbolic) curvature allowing for lossless/supra spin currents. Another strategy is to look for existing spin/precession anomalies and corresponding nonlinear holonomy conditions at the most fundamental level from the quark level to the cosmic scale. In these sceneries the geodesic attractor could control holonomy and curvature near the fixed points. It was proposed in 2002 that this should happen with electrons in atomic orbits showing a Berry phase part of the Rydberg or Sommerfeld fine structure constant and in 2003 that this effect could be responsible for (in)stabilities in the nuclear range and in superconductors. In 2008 it was shown that the attractor is part of the chaotic mechanical dynamics successfully at work in the Gyro-twister fitness device, and in 2007-2009 that there could be some deep relevance to ``anomalies'' in many scenarios even on the cosmic scales. Thus, we will point to and discuss some possible future applications that could be utilized for metric engineering: generating artificial holonomy and curvature (DC effect) for propulsion, or forcing holonomy waves (AC effect) in hyperbolic space-time, which are just gravitational waves interesting for communication.

Binder, Bernd

2009-03-01

354

Conformal anomaly actions for dilaton interactions

We discuss, in conformally invariant field theories such as QCD with massless fermions, a possible link between the perturbative signature of the conformal anomaly, in the form of anomaly poles of the 1-particle irreducible effective action, and its description in terms of Wess-Zumino actions with a dilaton. The two descriptions are expected to capture the UV and IR behaviour of the conformal anomaly, in terms of fundamental and effective degrees of freedom respectively, with the dilaton effective state appearing in a nonlinear realization. As in the chiral case, conformal anomalies seem to be related to the appearance of these effective interactions in the 1PI action in all the gauge-invariant sectors of the Standard Model. We show that, as a consequence of the underlying anomalous symmetry, the infinite hierarchy of recurrence relations involving self-interactions of the dilaton is entirely determined only by the first four of them. This relation can be generalized to any even space-time dimension.

Rose, Luigi Delle; Serino, Mirko

2014-01-01

355

Holographic models and the QCD trace anomaly

International Nuclear Information System (INIS)

Five dimensional dilaton models are considered as possible holographic duals of the pure gauge QCD vacuum. In the framework of these models, the QCD trace anomaly equation is considered. Each quantity appearing in that equation is computed by holographic means. Two exact solutions for different dilaton potentials corresponding to perturbative and non-perturbative ?-functions are studied. It is shown that in the perturbative case, where the ?-function is the QCD one at leading order, the resulting space is not asymptotically AdS. In the non-perturbative case, the model considered presents confinement of static quarks and leads to a non-vanishing gluon condensate, although it does not correspond to an asymptotically free theory. In both cases analyses based on the trace anomaly and on Wilson loops are carried out.

356

Anomaly cancellation in K3 orientifolds

International Nuclear Information System (INIS)

We study in detail the pattern of anomaly cancellation in D=6 Type IIB ZN orientifolds, occurring through a generalized Green-Schwarz mechanism involving several RR antisymmetric tensors and scalars fields. The starting point is a direct string theory computation of the inflow of anomaly arising from magnetic interaction of D-branes, O-planes and fixed points, which are encoded in topological one-loop partition functions in the RR odd spin-structure. All the RR anomalous couplings of these objects are then obtained by factorization. They are responsible for a spontaneous breaking of U(1) factors through a Higgs mechanism involving the corresponding hypermultiplets. Some of them are also related by supersymmetry to gauge couplings involving the NSNS scalars sitting in the tensor multiplets. We also comment on the possible occurrence of tensionless strings when these couplings diverge

357

Anomaly cancellation in K3 orientifolds

We study in detail the pattern of anomaly cancellation in D=6 Type IIB Z_N orientifolds, occurring through a generalized Green-Schwarz mechanism involving several RR antisymmetric tensors and scalars fields. The starting point is a direct string theory computation of the inflow of anomaly arising from magnetic interaction of D-branes, O-planes and fixed-points, which are encoded in topological one-loop partition functions in the RR odd spin-structure. All the RR anomalous couplings of these objects are then obtained by factorization. They are responsible for a spontaneous breaking of U(1) factors through a Higgs mechanism involving the corresponding hypermultiplets. Some of them are also related by supersymmetry to gauge couplings involving the NSNS scalars sitting in the tensor multiplets. We also comment on the possible occurrence of tensionless strings when these couplings diverge.

Scrucca, Claudio A; Scrucca, Claudio A.; Serone, Marco

2000-01-01

358

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)

359

Graviton as a Pair of Collinear Gauge Bosons

We show that the mixed gravitational/gauge superstring amplitudes describing decays of massless closed strings - gravitons or dilatons - into a number of gauge bosons, can be written at the tree (disk) level as linear combinations of pure open string amplitudes in which the graviton (or dilaton) is replaced by a pair of collinear gauge bosons. Each of the constituent gauge bosons carry exactly one half of the original closed string momentum, while their +/- 1 helicities add up to +/- 2 for the graviton or to 0 for the dilaton.

Stieberger, Stephan

2014-01-01

360

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

361

Confining gauge theories without Goldstone bosons

International Nuclear Information System (INIS)

We discuss the possibility that in the Wilson lattice definition of confining gauge theories without Goldstone bosons one may systematically adjust the lightest vector mass to zero while keeping the isosinglet scalar mass, which arises by the chiral anomaly, nontachyonic. We discuss a Weyl fermion theory and find the lightest vector particle to be an isoscalar (at least in strong coupling) so that there is no collision with known theorems. We discuss how an abelian gauge symmetry can arise as an infrared attractor and point out a difference between the Weyl fermion theory and one flavour QCD. Attention is also drawn to a physical motivation. (orig.)

362

Gauged flavour symmetry for the light generations

We study the phenomenology of a model where an SU(2)^3 flavour symmetry acting on the first two generation quarks is gauged and Yukawa couplings for the light generations are generated by a see-saw mechanism involving heavy fermions needed to cancel flavour-gauge anomalies. We find that, in constrast to the SU(3)^3 case studied in the literature, most of the constraints related to the third generation, like electroweak precision bounds or B physics observables, can be evaded, while characteristic collider signatures are predicted.

D'Agnolo, Raffaele Tito

2012-01-01

363

Gravitational Radiation from Oscillating Gravitational Dipole

The concept of Gravitational Dipole is introduced starting from the recent discovery of negative gravitational mass (gr-qc/0005107 and physics/0205089). A simple experiment, a gravitational wave transmitter, to test this new concept of gravitational radiation source is presented.

De Aquino, F

2002-01-01

364

Anomaly and Anomaly-Free Treatment of QFT's Based on Symmetry-Preserving Loop Regularization

The triangle anomaly in massless and massive QED is investigated by adopting the symmetry-preserving loop regularization method proposed recently in Refs. 1 and 2. The method is realized in the initial dimension of theory without modifying the original Lagrangian, it preserves symmetries under non-Abelian gauge and Poincaré transformations in spite of the existence of two intrinsic mass scales Mc and ?s which actually play the roles of UV- and IR-cutoff respectively. The axial-vector-vector-vector (AVV) triangle diagrams in massless and massive QED are evaluated explicitly by using the loop regularization. It is shown that when the momentum k of external state is soft with k2 << ? s2, m2 (m is the mass of loop fermions) and Mc ? ?, both massless and massive QED become anomaly free. The triangle anomaly is found to appear as quantum corrections in the case that m2, ? s2 << k2 and Mc ? ?. Especially, it is justified that in the massless QED with ?s = 0 and Mc ? ?, the triangle anomaly naturally exists as quantum effects in the axial-vector current when the ambiguity caused by the trace of gamma matrices with ?5 is eliminated by simply using the definition of ?5. It is explicitly demonstrated how the Ward identity anomaly of currents depends on the treatment for the trace of gamma matrices, which enables us to make a clarification whether the ambiguity of triangle anomaly is caused by the regularization scheme in the perturbation calculations or by the trace of gamma matrices with ?5. For comparison, an explicit calculation based on the Pauli-Villars regularization and dimensional regularization is carried out and the possible ambiguities of Ward identity anomalies caused from these two regularization schemes are carefully discussed, which include the ambiguities induced by the treatment of the trace of gamma matrices with ?5 and the action of the external momentum on the amplitude before the direct calculation of the AVV diagram.

Ma, Yong-Liang; Wu, Yue-Liang

365

Light-induced gauge fields for ultracold atoms

Gauge fields are central in our modern understanding of physics at all scales. At the highest energy scales known, the microscopic universe is governed by particles interacting with each other through the exchange of gauge bosons. At the largest length scales, our Universe is ruled by gravity, whose gauge structure suggests the existence of a particle—the graviton—that mediates the gravitational force. At the mesoscopic scale, solid-state systems are subjected to gauge fields of different nature: materials can be immersed in external electromagnetic fields, but they can also feature emerging gauge fields in their low-energy description. In this review, we focus on another kind of gauge field: those engineered in systems of ultracold neutral atoms. In these setups, atoms are suitably coupled to laser fields that generate effective gauge potentials in their description. Neutral atoms ‘feeling’ laser-induced gauge potentials can potentially mimic the behavior of an electron gas subjected to a magnetic field, but also, the interaction of elementary particles with non-Abelian gauge fields. Here, we review different realized and proposed techniques for creating gauge potentials—both Abelian and non-Abelian—in atomic systems and discuss their implication in the context of quantum simulation. While most of these setups concern the realization of background and classical gauge potentials, we conclude with more exotic proposals where these synthetic fields might be made dynamical, in view of simulating interacting gauge theories with cold atoms.

Goldman, N.; Juzeli?nas, G.; Öhberg, P.; Spielman, I. B.

2014-12-01

366

Trace anomaly and massless scalar degrees of freedom in gravity

International Nuclear Information System (INIS)

The trace anomaly of quantum fields in electromagnetic or gravitational backgrounds implies the existence of massless scalar poles in physical amplitudes involving the stress-energy tensor. Considering first the axial anomaly and using QED as an example, we compute the full one-loop triangle amplitude of the fermionic stress tensor with two current vertices, ??J?J?>, and exhibit the scalar pole in this amplitude associated with the trace anomaly, in the limit of zero electron mass m?0. To emphasize the infrared aspect of the anomaly, we use a dispersive approach and show that this amplitude and the existence of the massless scalar pole is determined completely by its ultraviolet finite terms, together with the requirements of Poincare invariance of the vacuum, Bose symmetry under interchange of J? and J?, and vector current and stress-tensor conservation. We derive a sum rule for the appropriate positive spectral function corresponding to the discontinuity of the triangle amplitude, showing that it becomes proportional to ?(k2) and therefore contains a massless scalar intermediate state in the conformal limit of zero electron mass. The effective action corresponding to the trace of the triangle amplitude can be expressed in local form by the introduction of two scalar auxiliary fields which satisfy massless wave equations. These massless scalar degrees of freedom couple to classical sources, dom couple to classical sources, contribute to gravitational scattering processes, and can have long range gravitational effects.

367

International Nuclear Information System (INIS)

A survey was made by Japan Atomic Industrial Forum, Inc., in August, 1979, on the uses of isotope-equipped measuring instruments in private industrial enterprises by sending questionnaires to 1372 enterprises using sealed radiation sources. The results are described. i.e. usage of isotope-equipped measuring instruments, the economic effects, and problems for the future, and also the general situation in this field. Such instruments used are gas chromatography apparatus, thickness, level and moisture gauges, sulfur analyzer, etc. Except the gas chromatography, the rest are mostly incorporated in automatic control systems. As the economic effects, there are the rises in productivity, quality and yield and the savings in materials, energy and manpower. While they are used to great advantage, there are still problems occasionally in measuring accuracy and others. (J.P.N.)

368

Analysis of the radio-metric data from Pioneer 10 and 11 spacecrafts has indicated the presence of an unmodeled acceleration starting at 20 AU, which has become known as the Pioneer anomaly. The nature of this acceleration is uncertain. In this paper we give a description of the effect and review some relevant mechanisms proposed to explain the observed anomaly. We also discuss on some future projects to investigate this phenomenon.

de Diego, Jose A

2008-01-01

369

We consider the effect that gravity has when one tries to set up a constant background form field. We find that in analogy with the Melvin solution, where magnetic field lines self-gravitate to form a flux-tube, the self-gravity of the form field creates fluxbranes. Several exact solutions are found corresponding to different transverse spaces and world-volumes, a dilaton coupling is also considered.

Saffin, P M

2001-01-01

370

Complex lymphatic anomalies include several diagnoses with overlapping patterns of clinical symptoms, anatomic location, imaging features, hematologic alterations, and complications. Lymphatic malformations likely arise through anomalous embryogenesis of the lymphatic system. Analysis of clinical, imaging, histologic, and hematologic features is often needed to reach a diagnosis. Aspiration of fluid collections can readily define fluid as chylous or not. The presence of chyle indicates dysfunction at the mesenteric or retroperitoneal level or above the cisterna chyli due to reflux. The imaging patterns of generalized lymphatic anomaly (GLA) and Gorham-Stout disease have been segregated with distinctive bone lesions and peri-osseous features. More aggressive histology (spindled lymphatic endothelial cells), clinical progression, hemorrhage, or moderate hematologic changes should raise suspicion for kaposiform lymphangiomatosis. Biopsy may be needed for diagnosis, though avoidance of rib biopsy is advised to prevent iatrogenic chronic pleural effusion. Lymphangiography can visualize the anatomy and function of the lymphatic system and may identify dysfunction of the thoracic duct in central conducting lymphatic anomalies. Local control and symptom relief are targeted by resection, laser therapy, and sclerotherapy. Emerging data suggest a role for medical therapies for complications of complex lymphatic anomalies. Outcomes include recurrent effusion, infection, pain, fracture, mortality, and rarely, malignancy. Complex lymphatic anomalies present significant diagnostic and therapeutic challenges. Results from a phase 2 study of sirolimus in these and other conditions are expected in 2014. Improved characterization of natural history, predictors of poor outcomes, responses to therapy, and further clinical trials are needed for complex lymphatic anomalies. PMID:25241096

Trenor, Cameron C; Chaudry, Gulraiz

2014-08-01

371

Utilitarian supersymmetric gauge model of particle interactions

International Nuclear Information System (INIS)

A remarkabale U(1) gauge extension of the supersymmetric standard model was proposed 8 years ago. It is anomaly free, has no ? 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.

372

Utilitarian Supersymmetric Gauge Model of Particle Interactions

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

373

Physical anomaly on the lattice

International Nuclear Information System (INIS)

The authors study the axial anomaly of chiral non-invariant generalized Wilson's action and point out a possibility that physical anomaly which is responsible for ?0 ? 2? decay and ?-eta-eta' mass difference vanishes. The physical anomaly is different from the commonly defined anomaly which has correct magnitude. (Auth.)

374

Supersymmetry breaking from superstrings and the gauge hierarchy

International Nuclear Information System (INIS)

The gauge hierarchy problem is reviewed and a class of effective field theories obtained from superstrings is described. These are characterized by a classical symmetry, related to the space-time duality of string theory, that is responsible for the suppression of observable supersymmetry breaking effects. At the quantum level, the symmetry is broken by anomalies that provide the seed of observable supersymmetry breaking, and an acceptably large gauge hierarchy may be generated. 39 refs

375

Electroweak phase transition in a model with gauged lepton number

In this work we study the electroweak phase transition in a model with gauged lepton number. Here, a family of vector-like leptons is required in order to cancel the gauge anomalies. Furthermore, these leptons can play an important role in the transition process. We find that this framework is able to provide a strong transition, but only for a very limited number of cases.

Aranda, Alfredo; Vaquera-Araujo, Carlos A

2014-01-01

376

Cosmic strings in a product Abelian gauge field theory

It is shown that multiply distributed cosmic strings arise in the product Abelian gauge field theory of Tong and Wong where vortices generated from an extra gauge sector are used to realize magnetic impurities. It is seen that, in view of the fully coupled Einstein and gauge-matter equations, the presence of such cosmic strings in the form of topological defects is essential for gravitation. Asymptotic behavior of the string solutions can be precisely described to allow the derivation of a necessary and sufficient condition for the gravitational metric to be geodesically complete and an explicit calculation of the deficit angle proportional to the string tension, both stated in terms of string numbers, energy levels of broken symmetries, and the universal gravitational constant.

Yang, Yisong

2014-08-01

377

Holographic anomaly in 3d f(Ric) gravity

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 o...

Loran, Farhang

2013-01-01

378

Holographic anomaly in 3d f(Ric) gravity

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

Loran, Farhang

2013-01-01

379

Holographic anomaly in 3D f(Ric) gravity

International Nuclear Information System (INIS)

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. (paper)

380

Z'-gauge Bosons as Harbingers of Low Mass Strings

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

381

Lattice fermions: Species doubling, chiral invariance and the triangle anomaly

International Nuclear Information System (INIS)

We investigate the formulation of fermions in lattice gauge theories, in weak coupling perturbation theory. It is shown that a lattice fermion formulation without species doubling and with explicit continuous chiral symmetry is impossible. We interpret this as a manifestation of the triangle anomaly. Green functions and (axial) vector flavor currents in lattice QCD with Wilson fermions are studied. We show that in the (weak coupling) continuum limit the theory is equivalent to perturbative continuum QCD: chiral invariant and with the usual anomaly in the flavor singlet axial current. (orig.)

382

Path integral measure for gravitational interactions

International Nuclear Information System (INIS)

It is pointed out that the path integral variables as well as the local measure for gravitational interactions are uniquely specified if one imposes the anomaly free condition on the Becchi-Rouet-Stora supersymmetry associated with general coordinate transformations. This prescription is briefly illustrated for the Einstein gravity and supergravity in four space-time dimensions and the relativistic string theory in two dimensions. (author)

383

Gauge models with spontaneously broken local supersymmetry

International Nuclear Information System (INIS)

An effective low-energy lagrangian for gauge theories based on local supersymmetry spontaneously broken at an intermediate energy between the weak interaction and the Planck scale is obtained. The derivation uses the general coupling of the Yang-Mills matter system to n = 1 supergravity. As illustrative examples of this framework we exhibit realistic models of supersymmetric QED and of the electroweak theory with supersymmetry breaking induced by purely gravitational effects. (orig.)

384

Eleven dimensional supergravity in light cone gauge

Digital Repository Infrastructure Vision for European Research (DRIVER)

Light-cone gauge manifestly supersymmetric formulation of eleven dimensional supergravity is developed. The formulation is given entirely in terms of light cone scalar superfield, allowing us to treat all component fields on an equal footing. All higher derivative on mass shell manifestly supersymmetric 4-point functions invariant with respect to linear supersymmetry transformations and corresponding (in gravitational bosonic sector) to terms constructed from four Riemann te...

Metsaev, R. R.

2004-01-01

385

Scalar-tensor theories, trace anomalies and the QCD-frame

We consider the quantum effects of matter fields in scalar-tensor theories and clarify the role of trace anomaly when switching between conformally related `frames'. We exploit the property that the couplings between the scalar and the gauge fields are not frame-invariant and define a `QCD-frame', where the scalar is not coupled to the gluons. This frame generalizes the `Jordan frame' in the case of non-metric theories and is particularly convenient for gravitational phenomenology. Test bodies have trajectories that are as close as possible to geodesics with respect to such a metric and equivalence principle violations are directly proportional to the scalar coupling parameters written in this frame. We show how RG flow and decoupling work in metric and non-metric theories. RG-running commutes with the operation of switching between frames at different scales. When only matter loops are considered, our analysis confirms that metricity is stable under radiative corrections and shows that approximate metricity ...

Nitti, Francesco

2012-01-01

386

Magnetic anomalies. [Magsat studies

The implications and accuracy of anomaly maps produced using Magsat data on the scalar and vector magnetic field of the earth are discussed. Comparisons have been made between the satellite maps and aeromagnetic survey maps, showing smoother data from the satellite maps and larger anomalies in the aircraft data. The maps are being applied to characterize the structure and tectonics of the underlying regions. Investigations are still needed regarding the directions of magnetization within the crust and to generate further correlations between anomaly features and large scale geological structures. Furthermore, an increased data base is recommended for the Pacific Ocean basin in order to develop a better starting model for Pacific tectonic movements. The Pacific basin was large farther backwards in time and subduction zones surround the basin, thereby causing difficulties for describing the complex break-up scenario for Gondwanaland.

Harrison, C. G. A.

1983-01-01

387

Anomaly Extraction in Networks

Directory of Open Access Journals (Sweden)

Full Text Available The application detects anomaly in network using techniques like histogram, cloning voting, filtering. To extract anomalous flows, one could build a model describing normal flow characteristics and use the model to identify deviating flows. We can compare flows of packets on network with previous flows, like new flows that were not previously observed or flows with significant increase/decrease in their volume. Identify an anomalous flow that combines and consolidates information from multiple histogram-based anomaly detectors [1] [4] [8]. Compared to other possible approaches. Build a histogram based detector that (i applies histogram cloning[1][4], i.e., maintains multiple randomized histograms to obtain additional views of network traffic[3]; and (ii uses the Kullback-Leibler (KL distance to detect anomalies.

Mr. Naushad Mujawar

2014-03-01

388

We find necessary and sufficient conditions for gauge invariance of the action of Double Field Theory (DFT) as well as closure of the algebra of gauge symmetries. The so-called weak and strong constraints are sufficient to satisfy them, but not necessary. We then analyze compactifications of DFT on twisted double tori satisfying the consistency conditions. The effective theory is a Gauged DFT where the gaugings come from the duality twists. The action, bracket, global symmetries, gauge symmetries and their closure are computed by twisting their analogs in the higher dimensional DFT. The non-Abelian heterotic string and lower dimensional gauged supergravities are particular examples of Gauged DFT.

Graña, Mariana

2012-01-01

389

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

390

Gravitational particle production by cosmic strings

Energy Technology Data Exchange (ETDEWEB)

We apply a perturbative treatment of quantum field theory in the presence of weak time-dependent gravitational fields to determine the rate of particle production by cosmic strings of several different types. We evaluate the effect that occurs during the formation of both gauge and global strings, while a current grows along a superconducting string, and by the oscillations of loops as well. The gravitational field of strings can produce very energetic particles, even at present times, but the flux would be too small to have observable consequences. (orig.).

Garriga, J.; Verdaguer, E. (Universidad Autonoma de Barcelona (Spain). Grupo de Fisica Teorica); Harari, D. (Florida Univ., Gainesville (USA). Dept. of Physics)

1990-07-30

391

Corrections to Schwarzschild solution in noncommutative gauge theory of gravity

International Nuclear Information System (INIS)

A deformed Schwarzschild solution in noncommutative gauge theory of gravitation is obtained. The gauge potentials (tetrad fields) are determined up to the second order in the noncommutativity parameters ???. A deformed real metric is defined and its components are obtained. The noncommutativity correction to the red shift test of general relativity is calculated and it is concluded that the correction is too small to have observable effects. Implications of such a deformed Schwarzschild metric are also mentioned

392

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

International Nuclear Information System (INIS)

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

393

...Gravitational Physics Group institute,physics,iop,gravity,gravitation,gravitational,groups This site uses cookies. By continuing to use this site you agree to our use of cookies. To find out more, see our Privacy and Cookies policy. IOP Institute of Physics For physics bull;...here Activities Groups All Groups Gravitational Physics Group Groups All Groups Gravitational Physics Group Committee Contact Group calendar Newsletter Thesis Prize Gravitational Physics Group Gravitation lies at the boundary of particle physics and cosmology. New insights into the relationship between gravitation and other forces will almost certainly ...

394

Anomalies are an infrared effect, but are often realized in effective theories in a non-trivial way. We study the chiral anomaly in Soft Collinear Effective Theory (SCET), where the anomaly equation has terms contributing at different orders in the power expansion. The chiral anomaly equations in SCET are computed up to NNLO in the power counting with external collinear and/or ultrasoft gluons. We do this by expanding the QCD anomaly equation, using the tree level (LO in \\alpha_s) relations between QCD and SCET fields. The validity of this correspondence between the anomaly equations is confirmed by direct computation of the one-loop diagrams in SCET.

Waalewijn, Wouter J

2008-01-01

395

Yang-Mills origin of gravitational symmetries

By regarding gravity as the convolution of left and right Yang-Mills theories, we derive in linearised approximation the gravitational symmetries of general covariance, p-form gauge invariance, local Lorentz invariance and local supersymmetry from the flat space Yang-Mills symmetries of local gauge invariance and global super-Poincar\\'e. As a concrete example we focus on the new-minimal (12+12) off-shell version of simple four-dimensional supergravity obtained by tensoring the off-shell Yang-Mills multiplets (4 + 4, N_L = 1) and (3 + 0, N_R = 0).

Anastasiou, A; Duff, M J; Hughes, L J; Nagy, S

2014-01-01

396

Induced quantum curvature and three-dimensional gauge theories

International Nuclear Information System (INIS)

The effects of quantum holonomy in three-dimensional gauge theories with massless fermions is examined and different definitions of the fermion determinant are discussed. The source of a global gauge and parity anomaly is identified in Schroedinger picture quantization as an induced holonomy that arises from the fermionic sector of the theory. In certain fermion representations this holonomy leads to a global obstruction ot imposing either gauge or parity invariance through the implementation of Gauss' law constraint. However, such obstructions can be removed by exploiting renormalization ambiguities inherent in the definition of composite operators. (orig.)

397

Aspects of N=2 supersymmetric gauge theories in three dimensions

International Nuclear Information System (INIS)

We consider general aspects of N=2 gauge theories in three dimensions, including their multiplet structure, anomalies and non-renormalization theorems. For U(1) gauge theories, we discuss the quantum corrections to the moduli space, and their relation to ''mirror symmetries'' of 3d N=4 theories. Mirror symmetry is given an interpretation in terms of vortices. For SU(Nc) gauge groups with Nf fundamental flavors, we show that, depending on the number of flavors, there are quantum moduli spaces of vacua with various phenomena near the origin. (orig.)

398

Antifield dependence of anomalies

International Nuclear Information System (INIS)

It is shown that generally the consistency equation for anomalies of quantum field theories has solutions which depend nontrivially on the sources of the (generalized) BRS-transformations of the fields. Explicit previously unknown examples of such solutions are given for Yang-Mills and super Yang-Mills theories. (orig.)

399

Energy Technology Data Exchange (ETDEWEB)

A record of the conclusions of a three-day meeting and workshop of the Committee for a National Magnetic Anomaly Map held in February 1976 is presented. The purpose of he workshop was to prepare a statement of the benefits, objectives, specifications, and requirements of a NMAM and establish a working plan for producing the map. (ACR)

1976-01-01

400

Post-Einsteinian tests of gravitation

International Nuclear Information System (INIS)

Einstein gravitation theory can be extended by preserving its geometrical nature but changing the relation between curvature and energy-momentum tensors. This change accounts for radiative corrections, replacing the Newton gravitation constant by two running couplings which depend on scale and differ in the two sectors of traceless and traced tensors. The metric and curvature tensors in the field of the Sun, which were obtained in previous papers within a linearized approximation, are then calculated without this restriction. Modifications of gravitational effects on geodesics are then studied, allowing one to explore phenomenological consequences of extensions lying in the vicinity of general relativity. Some of these extended theories are able to account for the Pioneer anomaly while remaining compatible with tests involving the motion of planets. The PPN ansatz corresponds to peculiar extensions of general relativity which do not have the ability to meet this compatibility challenge

401

Post-Einsteinian tests of linearized gravitation

International Nuclear Information System (INIS)

The general relativistic treatment of gravitation can be extended by preserving the geometrical nature of the theory but modifying the form of the coupling between curvature and stress tensors. The gravitation constant is thus replaced by two running coupling constants which depend on scale and differ in the sectors of traceless and traced tensors. When calculated in the solar system in a linearized approximation, the metric is described by two gravitation potentials. This extends the parametrized post-Newtonian (PPN) phenomenological framework while allowing one to preserve compatibility with gravity tests performed in the solar system. Consequences of this extension are drawn here for phenomena correctly treated in the linear approximation. We obtain a Pioneer-like anomaly for probes with an eccentric motion as well as a range dependence of Eddington parameter ? to be seen in light deflection experiments

402

Electroweak gauge-boson production at small transverse momentum

Energy Technology Data Exchange (ETDEWEB)

Using soft-collinear effective theory (SCET), one can factorize the cross section for electroweak gauge-boson production at hadron colliders and resum large logarithms to all orders. The naive factorization is broken by a collinear anomaly (CA), which leads to infrared safety at vanishing transverse momentum.

Wilhelm, Daniel [Johannes Gutenberg-Universitaet Mainz (Germany)

2012-07-01

403

International Nuclear Information System (INIS)

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 entang it. When the accelerating qubit is entangled with a stationary partner, the decoherence should induce a corresponding loss in teleportation fidelity

404

Massive graviton and determination of cosmological constant from gauge theory of gravity

International Nuclear Information System (INIS)

The universe contains a lot more than the eye meets . Sophisticated experiments search diligently for this invisible dark matter. Here we will describe some theoretical implications of the gravitational gauge theory recently proposed by Ning Wu (hep-th/0112062), namely the possibility of the existence of massive gravitons which fill the intergalactic space. Dark matter is an important problem in cosmology. In gravitational gauge field theory, the following effects should be taken into account to solve this problem: 1) The existence of massive graviton will have some contribution to the dark matter; 2) If the gravitational magnetic field is strong inside a celestial system, the gravitational Lorentz force will provide additional centripetal force for circular motion of a celestial object; 3) The existence of a factor which violate inverse square law of classical gravity. Combining general relativity and gravitational gauge theory the cosmological constant is determined theoretically. The cosmological constant is related to the average vacuum energy of the gravitational gauge field. Because the vacuum energy of the gravitational gauge field is negative, the cosmological constant is positive what generates repulsive force on stars to make the expansion rate of the Universe accelerated. A rough estimation of it gives out its magnitude order 10-52 m-2, which is well consistent with experimental results. (authors)

405

Covariant Quiver Gauge Theories

We consider dimensional reduction of gauge theories with arbitrary gauge group in a formalism based on equivariant principal bundles. For the classical gauge groups we clarify the relations between equivariant principal bundles and quiver bundles, and show that the reduced quiver gauge theories are all generically built on the same universal symmetry breaking pattern. The formalism enables the dimensional reduction of Chern-Simons gauge theories in arbitrary odd dimensionalities. The reduced model is a novel Chern-Simons-Higgs theory consisting of a Chern-Simons term valued in the residual gauge group plus a higher order gauge and diffeomorphism invariant coupling of Higgs fields with the gauge fields. We study the moduli spaces of solutions, which in some instances provide geometric representations of certain quiver varieties as moduli spaces of flat invariant connections. As physical applications, we consider dimensional reductions involving non-compact gauge supergroups as a means for systematically induci...

Szabo, Richard J

2014-01-01

406

Beltrami parametrization and gauging of Virasoro and w-infinity algebras

International Nuclear Information System (INIS)

The gauging of the Virasoro and w-infinity algebras are discussed from the point of view of BRST symmetry. Both algebras are realised as ''Russian formulas'' for the curvatures built from the generators of the Lie algebras and the corresponding gauge fields. 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). 21 refs

407

The Origin of Chiral Anomaly and the Noncommutative Geometry

Digital Repository Infrastructure Vision for European Research (DRIVER)

We describe the scalar and spinor fields on noncommutative sphere starting from canonical realizations of the enveloping algebra ${\\cal A}={\\cal U}{u(2))}$. The gauge extension of a free spinor model, the Schwinger model on a noncommutative sphere, is defined and the model is quantized. The noncommutative version of the model contains only a finite number of dynamical modes and is non-perturbatively UV-regular. An exact expresion for the chiral anomaly is found. In the commu...

Presnajder, Peter

1999-01-01

408

A new sphaleron for the non-Abelian anomaly

A self-consistent Ansatz for a new sphaleron of SU(3) Yang-Mills-Higgs theory is presented. With a single triplet of Weyl fermions added, there exists one pair of fermion zeromodes, which is known to give rise to the non-Abelian (Bardeen) anomaly as a Berry phase. The corresponding sphaleron-like SU(3) gauge field configuration could take part in the nonperturbative dynamics of Quantum Chromodynamics.

Klinkhamer, F R

2004-01-01

409

Anomaly-induced inflaton decay and gravitino-overproduction problem

International Nuclear Information System (INIS)

We point out that the inflaton spontaneously decays into any gauge bosons and gauginos via the super-Weyl, Kahler and sigma-model anomalies in supergravity, once the inflaton acquires a non-vanishing vacuum expectation value. In particular, in the dynamical supersymmetry breaking scenarios, the inflaton necessarily decays into the supersymmetry breaking sector, if the inflaton mass is larger than the dynamical scale. This generically causes the overproduction of the gravitinos, which severely constrains the inflation models. (orig.)

410

The Chiral Magnetic Effect and Anomaly-Induced Transport

Digital Repository Infrastructure Vision for European Research (DRIVER)

The Chiral Magnetic Effect (CME) is the phenomenon of electric charge separation along the external magnetic field that is induced by the chirality imbalance. The CME is a macroscopic quantum effect - it is a manifestation of the chiral anomaly creating a collective motion in Dirac sea. Because the chirality imbalance is related to the global topology of gauge fields, the CME current is topologically protected and hence non-dissipative even in the presence of strong interact...

Kharzeev, Dmitri E.

2013-01-01

411

Coulomb gauge quantization of the Maxwell--Chern--Simons theory

Energy Technology Data Exchange (ETDEWEB)

The Maxwell--Chern--Simons theory is canonically quantized in the Coulomb gauge by using the Dirac bracket quantization procedure. The determination of the Coulomb gauge polarization vector turns out to be intricate. A set of quantum Poincare densities obeying the Dirac--Schwinger algebra and, therefore, free of anomalies is constructed. The peculiar analytical structure of the polarization vector is shown to be at the root for the existence of spin of the massive gauge quanta. The Coulomb gauge Feynman rules are used to compute the Moeller scattering amplitude in the lowest order of perturbation theory. The result coincides with that obtained by using covariant Feynman rules. This proof of equivalence is afterwards extended to all orders of perturbation theory. The so-called infrared safe photon propagator emerges as an effective propagator which allows for replacing all the terms in the interaction Hamiltonian of the Coulomb gauge by the standard field-current minimal interaction. {copyright} 1995 Academic Press, Inc.

Devecchi, F.P.; Fleck, M.; Girotti, H.O. [Instituto de Fisica, Universidade Federal do Rio Grande do Sul, Caixa Postal 15051, 91501-970, Porto Alegre, RS (Brazil); Gomes, M.; Da Silva, A.J. [Instituto de Fisica, Universidade de Sao Paulo, Caixa Postal 20516, 01452-990, Sao Paulo, SP (Brazil)

1995-09-01

412

Holographic models for the pure gauge quantum chromodynamics (QCD) vacuum are explored. The holographic renormalization of these models is considered as required by a phenomenological approach that takes the ?-functions of the models as the only input. This approach is done taking the dilaton as the coordinate orthogonal to the border. This choice greatly simplifies the analysis and gives a geometrical interpretation for the fixed points of the renormalization group flow. Examples are constructed that present asymptotic freedom, confinement of static quarks, either with vanishing or nonvanishing gluon condensate G2. The latter models require an extension of the dilaton-gravity models already considered in the literature. This extension is also determined by the only input, i.e. the ?-function. In addition, the restrictions imposed by the trace anomaly equation (TAE) are studied. In doing so, a holographic derivation of this equation is presented.

Trinchero, R. C.

2014-09-01

413

Detection of network traffic anomalies

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper describes various network monitoring technologies and anomaly detection methods. NetFlow were chosen for anomaly detection system being developed. Anomalies are detected using a deviation value. After evaluating quality of developed system, new enhancements were suggested and implemented. Flow data distribution was suggested, to achieve more precise NetFlow data representation, enabling a more precise network monitoring information usage for anomaly detection. Arithmetic average ca...

Krakauskas, Vytautas

2006-01-01

414

Antler anomalies were evident in tule elk (Cervus elaphus nannodes) within 1 yr of reintroduction to Point Reyes, California (USA). These anomalies are consistent with previously described mineral deficiency-induced anomalies in cervids. The elk were judged deficient in copper. Low levels of copper in soils and vegetation at the release site, exacerbated by possible protein deficiency due to poor range conditions, are postulated as likely causes of the antler anomalies. PMID:3193560

Gogan, P J; Jessup, D A; Barrett, R H

1988-10-01

415

Antler anomalies were evident in tule elk (Cervus elaphus nannodes) within 1 yr of reintroduction to Point Reyes, California (USA). These anomalies are consistent with previously described mineral deficiency-induced anomalies in cervids. The elk were judged deficient in copper. Low levels of copper in soils and vegetation at the release site, exacerbated by possible protein deficiency due to poor range conditions, are postulated as likely causes of the antler anomalies.

Gogan, Peter J.P.; Jessup, David A.; Barrett, Reginald H.

1988-01-01

416

Hawking radiation via Anomaly and Tunneling method from Unruh's and Canonical acoustic black hole

Digital Repository Infrastructure Vision for European Research (DRIVER)

Hawking radiation from Unruh's and Canonical acoustic black hole is considered from viewpoint of anomaly cancellation method developed by Robinson and Wilczek. Thus, the physics near the horizon can be described using an infinite collection of massless two-dimensional scalar fields in the background of a dilaton and the gravitational anomaly is canceled by the flux of a 1 + 1 dimensional blackbody at the Hawking temperature of the space-time. Consequently, by this method, we...

Becar, Ramon; Gonzalez, Pablo; Pulgar, Gustavo; Saavedra, Joel

2008-01-01

417

Strain gauge installation tool

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

418

We present a new method of gauge fixing to standard lattice Landau gauge, Max Re Tr $\\sum_{\\mu,x}U_{\\mu,x}$, in which the link configuration is recursively smeared; these smeared links are then gauge fixed by standard extremization. The resulting gauge transformation is simultaneously applied to the original links. Following this preconditioning, the links are gauge fixed again as usual. This method is free of Gribov copies, and we find that for physical parameters ($\\beta \\geq 2$ in SU(2)), it generally results in the gauge fixed configuration with the globally maximal trace. This method is a general technique for finding a unique minimum to global optimization problems.

Hetrick, J E; Forcrand, Ph. de

1998-01-01

419

The gravitational field at spatial infinity

International Nuclear Information System (INIS)

This paper treats the formulation of the gravitational field variables and the equations obeyed by them at spatial infinity. The variables consist of a three-dimensional tensor and a scalar, which satisfy separate field equations, which in turn can be obtained from two distinct Lagrangians. Aside from Lorentz rotations, the symmetry operations include an Abelian gauge group and an Abelian Lie group, leading to a number of conservation laws and to differential indentities between the field equations

420

Ghost properties of generalized theories of gravitation

International Nuclear Information System (INIS)

We investigate theories of gravitation, in which spacetime is non-Riemannian and the metric g/sub munu/ is nonsymmetric, for ghosts and tachyons, using a spin-projection operator formalism. Ghosts are removed not by gauge invariance but by a Lagrange multiplier W/sub ?/, which occurs due to the breaking of projective invariance in the theory. Unified theories based on a Lagrangian containing a term lambdag/sup munu/g/sub / are proved to contain ghosts or tachyons

421

Instabilities in the nonsymmetric theory of gravitation

Digital Repository Infrastructure Vision for European Research (DRIVER)

We consider the linearized nonsymmetric theory of gravitation (NGT) within the background of an expanding universe and near a Schwarzschild metric. We show that the theory always develops instabilities unless the linearized nonsymmetric lagrangian reduces to a particular simple form. This theory contains a gauge invariant kinetic term, a mass term for the antisymmetric metric-field and a coupling with the Ricci curvature scalar. This form cannot be obtained within NGT. Next ...

Janssen, Tomas; Prokopec, Tomislav

2006-01-01

422

Mechanical analogies for gravitation

Digital Repository Infrastructure Vision for European Research (DRIVER)

A quasielastic model of gravitation is developed. Gravitational field is modeled by the flow of the transient point dilatation, which is supposed to be continually emitted by a discontinuity of the turbulent fluid. Gravitational attraction arises from the contact interaction of the dilatation centers. Gravitational wave is viewed microscopically as the axisymmetric wave propagating at a high speed along a vortex tube.

Dmitriyev, Valery P.

1999-01-01

423

Constraining an Expanding Locally Anisotropic metric from the Pioneer anomaly

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

424

Improved moving puncture gauge conditions for compact binary evolutions

Robust gauge conditions are critically important to the stability and accuracy of numerical relativity (NR) simulations involving compact objects. Most of the NR community use the highly robust—though decade-old—moving-puncture (MP) gauge conditions for such simulations. It has been argued that in binary black hole evolutions adopting this gauge, noise generated near adaptive-mesh-refinement (AMR) boundaries does not converge away cleanly with increasing resolution, severely limiting gravitational waveform accuracy at computationally feasible resolutions. We link this noise to a sharp (short-wavelength), initial outgoing gauge wave crossing into progressively lower resolution AMR grids and present improvements to the standard MP gauge conditions that focus on stretching, smoothing, and more rapidly settling this outgoing wave. Our best gauge choice greatly reduces gravitational waveform noise during inspiral, yielding less fluctuation in convergence order and ˜40% lower waveform phase and amplitude errors at typical resolutions. Noise in other physical quantities of interest is also reduced, and constraint violations drop by more than an order of magnitude. We expect these improvements will carry over to simulations of all types of compact binary systems, as well as other N +1 formulations of gravity for which MP-like gauge conditions can be chosen.

Etienne, Zachariah B.; Baker, John G.; Paschalidis, Vasileios; Kelly, Bernard J.; Shapiro, Stuart L.

2014-09-01

425

Developmental anomalies associated with hypospadias.

Directory of Open Access Journals (Sweden)

Full Text Available Hundred and thirty patients with hypospadias were studied between 1983 and 1990, with an aim of analysing the associated anomalies in these patients. Urogenital anomalies were observed in 30% and extra-urogenital anomalies were noted in 16%. Undescended testis was the most frequently seen anomaly, having been noted in 6.9% of 130 cases. Vesico-ureteral reflux was present in 5.4% and inguinal hernia in 3.8%. The incidence of these anomalies increased in proportion to the severity of penile deformity. The present article emphasizes the need for systemic urological and endocrinal examination, especially in severe cases of hypospadias.

Kulkarni B

1991-07-01

426

Energy Technology Data Exchange (ETDEWEB)

We show the existence of a global anomaly in the one-loop graphs of N=2 string theory, defined by sewing tree amplitudes, unless spacetime supersymmetry is imposed. The anomaly is responsible for the non-vanishing maximally helicity violating amplitudes. The supersymmetric completion of the N=2 string spectrum is formulated by extending the previous cohomological analysis with an external spin factor; the target space-time spin-statistics of these individual fields in a self-dual background are compatible with previous cohomological analysis as fields of arbitrary spin may be bosonized into one another. We further analyze duality relations between the open and closed string amplitudes and demonstrate this in the supersymmetric extension of the target space-time theory through the insertion of zero-momentum operators.

Chalmers, Gordon; Siegel, Warren

2001-07-15

427

A noncommutative anomaly through Seiberg-Witten map and non-locally regularized BV quantization

Anomalies are one essential concept for the renormalization of noncommutative (NC) gauge theories. A NC space can be visualized as a deformation of the usual spacetime with the $\\star$-product and can be constructed after the quantization of a given space with its symplectic structure. The Seiberg-Witten (SW) map connects NC fields, transformations parameters and gauge potential to their commutative analogs. In this work we used the SW map to calculate the NC version of the anomaly of the BV quantized chiral Schwinger model with nonlocal regularization.

Abreu, Everton M C

2013-01-01

428

We present a mapping of quantum many body states with a global symmetry to states with local gauge symmetry. The prescription implements the principle of minimal coupling at the level of individual quantum states as opposed to Hamiltonians or Lagrangians. Using the formalism of projected entangled-pair states (PEPS), we construct an associated gauging map for Hamiltonians and show how this results in a frustration free gauge theory Hamiltonian. This procedure reproduces the minimal coupling scheme for the matter terms and automatically generates gauge dynamics closely related to the Kogut-Susskind Hamiltonian at zero coupling constant. We can then introduce gauge dynamics at finite values of the coupling constant by applying a local filtering operation. The gauging procedure transforms an injective PEPS for the matter fields into a G-injective PEPS for the combined gauge-matter system, which potentially has topological order. This scheme results in a low-parameter family of gauge invariant states of which we ...

Haegeman, Jutho; Schuch, Norbert; Cirac, J Ignacio; Verstraete, Frank

2014-01-01

429

We consider abelian gauge theories on a lattice and develop properties of an axial gauge that is covariant under lattice symmetries. Particular attention is paid to a version that behaves nicely under block averaging renormalization group transformations.

Dimock, J

2014-01-01

430

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

431

Gravity duals of supersymmetric gauge theories on three-manifolds

We study gravity duals to a broad class of N=2 supersymmetric gauge theories defined on a general class of three-manifold geometries. The gravity backgrounds are based on Euclidean self-dual solutions to four-dimensional gauged supergravity. As well as constructing new examples, we prove in general that for solutions defined on the four-ball the gravitational free energy depends only on the supersymmetric Killing vector, finding a simple closed formula when the solution has U(1) x U(1) symmetry. Our result agrees with the large N limit of the free energy of the dual gauge theory, computed using localization. This constitutes an exact check of the gauge/gravity correspondence for a very broad class of gauge theories with a large N limit, defined on a general class of background three-manifold geometries.

Farquet, Daniel; Martelli, Dario; Sparks, James

2014-01-01

432

Cosmological perturbation theory in the synchronous vs. conformal Newtonian gauge

We present a systematic treatment of the linear theory of scalar gravitational perturbations in the synchronous gauge and the conformal Newtonian (or longitudinal) gauge. We first derive the transformation law relating the two gauges. We then write down in parallel in both gauges the coupled, linearized Boltzmann, Einstein and fluid equations that govern the evolution of the metric perturbations and the density fluctuations of the particle species. The particle species considered include cold dark matter (CDM), baryons, photons, massless neutrinos, and massive neutrinos (a hot dark matter or HDM candidate), where the CDM and baryon components are treated as fluids while a detailed phase-space description is given to the photons and neutrinos. The linear evolution equations presented are applicable to any $\\Omega=1$ model with CDM or a mixture of CDM and HDM. Isentropic initial conditions on super-horizon scales are derived. The equations are solved numerically in both gauges for a CDM+HDM model with $\\Omega_{...

Ma Chung Pei; Chung-Pei Ma; Edmund Bertschinger

1994-01-01

433

Combined supersymmetric and gauge-invariant field theories

International Nuclear Information System (INIS)

The combined supersymmetric and gauge-invariant field theories are formulated using ordinary fields, not superfields, from the start, thereby eliminating reference to superfluous components. The construction is a generalization to supersymmetry of the minimal-coupling procedure of ordinary gauge theories. The Lagrangians obtained coincide with those of the superfield approach in the Wess-Zumino gauge. The Ward-Takahashi identities of Green's functions for fields and supersymmetry currents are obtained by functional methods. The Ward-Takahashi identities are presented in a form from which low-energy theorems for Goldstone fermions can be directly derived, and the proof of the Goldstone theorem in these combined theories is clarified. Discussion of the closure of the supersymmetry algebra leads to the concept of gauge-invariant translations for which the conserved current is a gravitational energy-momentum tensor. Some of the results are valid in a broader context than supersymmetry and are applicable to gauge theories in general

434

Anomalies and nonperturbative results

We investigate nonperturbative effects in N=1 and N=2 supersymmetric theories using a relation between perturbative and exact anomalies as a starting point. For N=2 supersymmetric SU(n) Yang-Mills theory we derive the general structure of the Picard-Fuchs equations; for N=1 supersymmetric Yang-Mills theories we find holomorphic part of the superpotential (with gluino condensate) exactly.

Pronin, P I

1998-01-01

435

Digital Repository Infrastructure Vision for European Research (DRIVER)

Just as gauge theory describes the parallel transport of point particles using connections on bundles, higher gauge theory describes the parallel transport of 1-dimensional objects (e.g. strings) using 2-connections on 2-bundles. A 2-bundle is a categorified version of a bundle: that is, one where the fiber is not a manifold but a category with a suitable smooth structure. Where gauge theory uses Lie groups and Lie algebras, higher gauge theory uses their categorified analog...

Baez, John C.; Schreiber, Urs

2005-01-01

436

On the covariant gauge {alpha} of the linearized gravity in de Sitter spacetime

Energy Technology Data Exchange (ETDEWEB)

In previous work, we studied the linearized gravity with covariant gauge {beta}= 2/3 and {alpha}= 5/3. It was found that the sum of the source and initial contributions reproduces the correct field configuration over the whole de Sitter spacetime. In this paper, we extend this work to generalizing the linearized gravitational field in an arbitrary value of the gauge parameter {alpha} but the gauge parameter {beta} remains the same.

Cheong, Lee Yen [Department of Fundamental and Applied Science Universiti Teknologi Petronas, Bandar Seri Iskandar, 31750 Tronoh, Perak (Malaysia)

2012-09-26

437

Gauge theories, black hole evaporation and cosmic censorship

International Nuclear Information System (INIS)

Recent work of Linde, which suggests that gauge theories modify the effective gravitational constant, are applied to the theory of black hole evaporation. Considerable modification of the late stages of evaporation are predicted. Contrary to expectations, the black hole never attains a sufficient temperature to enter the antigravity regime, which would represent a failure of cosmic censorship. (orig.)

438

Quantum theory of gauge fields in Robertson-Walker spacetime

International Nuclear Information System (INIS)

Exploiting the Lagrange multiplier formalism developed by Kugo and Ojima we give a canonical quantization scheme for non-Abelian gauge theories in curved spacetime. As a first step in a general study of cosmological particle production we investigate the production of non-interacting particles and show, that unphysical particles are absent from the spectrum of particles produced by the gravitational field. (author)

439

International Nuclear Information System (INIS)

A method of the construction of the superfield normal gauge in the vicinity of a fixed point is given. In order to construct gauge-invariant theoretical quantities the question on the normal gauge application to the supergravity theory is discussed

440

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

441

On the localization of the gravitational energy

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English 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 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.

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

442

On the localization of the gravitational energy

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English 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 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.

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

2000-03-01

443

Renormalisation group, trace anomaly and Feynman-Hellmann theorem

We show that the logarithmic derivative of the gauge coupling on the hadronic mass and the cosmological constant term of a gauge theory are related to the gluon condensate of the hadron and the vacuum respectively. These relations are akin to Feynman-Hellmann relations whose derivation for the case at hand is complicated by the construction of the gauge theory Hamiltonian. We bypass this problem by using a renormalisation group equation for composite operators and the trace anomaly. The relations serve as possible definitions of the gluon condensates themselves which are plagued in direct approaches by power divergences. In turn these results might help to determine the contribution of the QCD phase transition to the cosmological constant and test speculative ideas.

Del Debbio, Luigi; Zwicky, Roman

2014-06-01

444

Anomalies and tadpoles in open/closed string duality

International Nuclear Information System (INIS)

We discuss the role played by the divergences appearing in the interaction between a fractional D3 brane dressed with an SU(N) gauge field and a stack of N fractional D3 branes on the orbifolds C2/Z2 and C3/(Z2 x Z2). In particular we show that the logarithmic divergences in the closed string channel, interpreted as due to twisted massless tadpoles, are mapped, under open/closed string duality, in the logarithmic ones in the open string channel, due to the massless states circulating in the annulus diagram and corresponding to the one-loop divergences that one finds in the gauge theory living in the worldvolume of the brane. This result provides quantitative evidence of why the chiral and scale anomalies of the supersymmetric and non-conformal gauge theories supported by the worldvolume of the branes can be inferred from supergravity calculations

445

Renormalization group, trace anomaly and Feynman-Hellmann theorem

We show that the logarithmic derivative of the gauge coupling on the hadronic mass and the cosmological constant term of a gauge theory are related to the gluon condensate of the hadron and the vacuum respectively. These relations are akin to Feynman-Hellmann relations whose derivation for the case at hand are complicated by the construction of the gauge theory Hamiltonian. We bypass this problem by using a renormalisation group equation for composite operators and the trace anomaly. The relations serve as possible definitions of the gluon condensates themselves which are plagued in direct approaches by power divergences. In turn these results might help to determine the contribution of the QCD phase transition to the cosmological constant and test speculative ideas.

Del Debbio, Luigi

2013-01-01

446

Linearization of Maxwell equations in the field of a weak gravitational wave

International Nuclear Information System (INIS)

In order to give a correct treatment of an electromagnetic gravitational wave detector, the correct form of the linearized Maxwell equations in the field of a gravitational wave is established by various arguments. It is shown to agree with the correct equations first found by Cooperstock when the harmonic gauge condition is imposed. The result is compared with other incorrect forms in the literature

447

Gravitational Lens Time Delays and Gravitational Waves

Digital Repository Infrastructure Vision for European Research (DRIVER)

Using Fermat's principle, we analyze the effects of very long wavelength gravitational waves upon the images of a gravitationally lensed quasar. We show that the lens equation in the presence of gravity waves is equivalent to that of a lens with different alignment between source, deflector, and observer in the absence of gravity waves. Contrary to a recent claim, we conclude that measurements of time delays in gravitational lenses cannot serve as a method to detect or const...

Frieman, J.; Harari, D.; Surpi, G.

1994-01-01

448

Scale Invariant Theory of Gravitation in Einstein-Rosen Space-Time

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, we have studied the perfect fluid distribution in the scale invariant theory of gravitation, when the space-time described by Einstein-Rosen metric with a time dependent gauge function. The cosmological equations for this space-time with gauge function are solved and some physical properties of the model are studied.

Pradyumn Kumar Sahoo

2010-09-01

449

A holomorphic anomaly in the elliptic genus

We consider a class of gauged linear sigma models (GLSMs) in two dimensions that flow to non-compact (2,2) superconformal field theories in the infra-red, a prototype of which is the SL(2,\\IR)/U(1) (cigar) coset. We compute the elliptic genus of the GLSMs as a path-integral on the torus using supersymmetric localization. We find that the result is a Jacobi-like form that is non-holomorphic in the modular parameter $\\tau$ of the torus, with mock modular behavior. This agrees with a previously-computed expression in the cigar coset. We show that the lack of holomorphicity of the elliptic genus arises from the contributions of a compact boson with momentum and winding around the torus. This boson has an axionic shift symmetry and plays the role of a compensator field that is needed to cancel the chiral anomaly in the rest of the theory.

Murthy, Sameer

2013-01-01

450

Abelian gauge structure inside nonabelian gauge theories

International Nuclear Information System (INIS)

We show that the inclusion of topological lagrangians in nonabelian gauge theories introduces certain topologically nontrivial abelian background fields in the configuration space of these theories. In particular, the theta-term and the topological mass term lead, respectively, to a vortex and a monopole in gauge orbit space in 3+1 and 2+1 dimensions. The identification of the theta-vacuum effect with a kind of Bohm-Aharonov effect in gauge-orbit space motivates a discussion on the possibility of solving the strong CP problem dynamically. (orig.)

451

Numerically generated black-hole spacetimes: Interaction with gravitational waves

International Nuclear Information System (INIS)

In this paper we present results from a new two-dimensional numerical relativity code used to study the interaction of gravitational waves with a black hole. The initial data correspond to a single black hole superimposed with time-symmetric gravitational waves (Brill waves). A gauge-invariant method is presented for extracting the gravitational waves from the numerically generated spacetime. We show that the interaction between the gravitational wave and the black hole excites the quasinormal modes of the black hole. An extensive comparison of these results is made to black-hole perturbation theory. For low-amplitude initial gravitational waves, we find excellent agreement between the theoretically predicted scrl=2 and scrl=4 wave forms and the wave forms generated by the code. Additionally, a code test is performed wherein the propagation of the wave on the black-hole background is compared to the evolution predicted by perturbation theory

452

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

International Nuclear Information System (INIS)

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.

453

Gauge-Fixing and Residual Symmetries in Gauge/Gravity Theories with Extra Dimensions

We study compactified pure gauge/gravitational theories with gauge-fixing terms and show that these theories possess quantum mechanical SUSY-like symmetries between unphysical degrees of freedom. These residual symmetries are global symmetries and generated by quantum mechanical N=2 supercharges. Also, we establish 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 $\\xi$-independent and the cancellation of the $\\xi$-dependence is ensured by the residual symmetries. We also give a simple interpretation of the vDVZ-discontinuity, which arises in the lowest tree-level approximation, from the supersymmetric point of view.

Lim, C S; Ohya, Satoshi; Sakamoto, Kazuki; Sakamoto, Makoto

2008-01-01

454

Anomalies of rhenium microhardness

International Nuclear Information System (INIS)

On the polar diagram microhardness of a rhenium monocrystal rotated around the axis [1010], the hardness minimum has been found out on indentation in directions inclined to the plane [1120A s at 10-30 deg angles. imilar minimum is revealed also on the azimuthal diagram of microhardness in the plane [1010]. Coefficients of microhardness anisotropy of the first and second kind for rhenium are determined. It is shown that microhardness anomalies can be caused by peculiarities of bonding forces and resistance to plastic flow in hexagonal metals

455

A model for the Pioneer Anomaly

We propose an explanation to the Pioneer Anomaly, the anomalous blueshift in the radio signals from the Pioneer 10/11 spacecrafts that remains unexplained 30 years after being discovered by a NASA team around 1975. It was detected as a Doppler shift that does not correspond to any known motion of the ships. In 1998, after many unsuccessful efforts to account for it, the discoverers suggested "the possibility that the origin of the anomalous signal is new physics". We show here that the phenomenon has the same observational footprint as an acceleration of the atomic clocks time with respect to the astronomical time. Surprisingly, this curious new idea turns out to be compatible with current physics; lacking a unified theory of quantum physics and gravitation, we cannot discard it a priori. We expound a mechanism that produces such an acceleration as a result of the coupling of the background gravitation and the quantum vacuum. This suggests a solution to the riddle, in which the velocity of a receding ship, as...

Ranada, A F; Ranada, Antonio F.; Tiemblo, Alfredo

2006-01-01

456

Gravity anomalies, forearc morphology and seismicity in subduction zones

We apply spectral averaging techniques to isolate and remove the long-wavelength large-amplitude trench-normal topographic and free-air gravity anomaly "high" and "low" associated with subduction zones. The residual grids generated illuminate the short-wavelength structure of the forearc. Systematic analysis of all subduction boundaries on Earth has enabled a classification of these grids with particular emphasis placed on topography and gravity anomalies observed in the region above the shallow seismogenic portion of the plate interface. The isostatic compensation of these anomalies is investigated using 3D calculations of the gravitational admittance and coherence. In the shallow region of the megathrust, typically within 100 km from the trench, isolated residual anomalies with amplitudes of up to 2.5 km and 125 mGal are generally interpreted as accreted/subducting relief in the form of seamounts and other bathymetric features. While most of these anomalies, which have radii 1000 km) trench-parallel forearc ridges with residual anomalies of up to 1.5 km and 150 mGal are identified in approximately one-third of the subduction zones analyzed. Despite great length along strike, these ridges are less than 100 km wide and several appear uncompensated. A high proportion of arc-normal structure and the truncation/morphological transition of trench-parallel forearc ridges is explained through the identification and tracking of pre-existing structure on the over-riding and subducting plates into the seismogenic portion of the plate boundary. Spatial correlations between regions with well-defined trench-parallel forearc ridges and the occurrence of large magnitude interplate earthquakes, in addition to the uncompensated state of these ridges, suggest links between the morphology of the forearc and the peak earthquake stress drop on the subduction megathrust. We present our classification of residual bathymetric and gravitational anomalies using examples from Sumatra, Kuril-Kamchatka, Mariana, Peru-Chile and the Tonga-Kermadec margin. We reassess proposed links between trench-parallel residual topography and gravity anomalies and subduction zone seismicity using global earthquake catalogs and a new compilation of published aftershock locations and distributed slip models from over 200 of the largest subduction zone earthquakes. Our results highlight the role of pre-existing structure in both the over-riding and subducting plates in modulating the along- and across-strike segmentation of subduction zones. Understanding the genesis of long-wavelength trench-parallel forearc ridges may provide further insights into links between forearc morphology, the rheology of the overriding and subducting plates and seismicity in subduction zones.

Bassett, D.; Watts, A. B.; Das, S.

2012-12-01

457

Wormhole solutions in a local scale invariant gravitation theory

International Nuclear Information System (INIS)

We study a local scale invariant theory composed of the gravitation field, the scalar field and the scale gauge field. We find a group of degenerate O(4) symmetric solutions of euclidean gravity. One of the solutions is the usual wormhole solution while the others are lacking obvious physical meaning and might be regarded as possible field configurations in the very early universe. (orig.)

458

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)

459

DEFF Research Database (Denmark)

Timing anomalies make worst-case execution time analysis much harder, because the analysis will have to consider all local choices. It has been widely recognised that certain hardware features are timing anomalous, while others are not. However, defining formally what a timing anomaly is, has been difficult. We examine previous definitions of timing anomalies, and identify examples where they do not align with common observations. We then provide a definition for consistently slower hardware traces that can be used to define timing anomalies and aligns with common observations.

Cassez, Franck; Hansen, Rene Rydhof

2012-01-01

460

Einstein, Entropy and Anomalies

This paper strengthens and defends the pluralistic implications of Einstein's successful, quantitative predictions of Brownian motion for a philosophical dispute about the nature of scientific advance that began between two prominent philosophers of science in the second half of the twentieth century (Thomas Kuhn and Paul Feyerabend). Kuhn promoted a monistic phase-model of scientific advance, according to which a paradigm driven `normal science' gives rise to its own anomalies, which then lead to a crisis and eventually a scientific revolution. Feyerabend stressed the importance of pluralism for scientific progress. He rejected Kuhn's model arguing that it fails to recognize the role that alternative theories can play in identifying exactly which phenomena are anomalous in the first place. On Feyerabend's account, Einstein's predictions allow for a crucial experiment between two incommensurable theories, and are an example of an anomaly that could refute the reigning paradigm only after the development of a competitor. Using Kuhn's specification of a disciplinary matrix to illustrate the incommensurability between the two paradigms, we examine the different research strategies available in this peculiar case. On the basis of our reconstruction, we conclude by rebutting some critics of Feyerabend's argument.

Sirtes, Daniel; Oberheim, Eric

2006-11-01

461

The Lense-Thirring Effect and the Pioneer Anomaly:. Solar System Tests

We report on a test of the Lense-Thirring effect with the Mars Global Surveyor orbiter and on certain features of motion of Uranus, Neptune and Pluto which contradict the hypothesis that the Pioneer anomaly can be caused by some gravitational mechanism.

Iorio, Lorenzo

2008-09-01

462

Lattice gauge theory approach to quantum chromodynamics

International Nuclear Information System (INIS)

The author reviews in a pedagogical fashion some of the recent developments in lattice quantum chromodynamics. This review emphasizes explicit examples and illustrations rather than general proofs and analyses. It begins with a discussion of the heavy-quark potential in continuum quantum chromodynamics. Asymptotic freedom and renormalization-group improved perturbation theory are discussed. A simple dielectric model of confinement is considered as an intuitive guide to the vacuum of non-Abelian gauge theories. Next, the Euclidean form of lattice gauge theory is introduced, and an assortment of calculational methods are reviewed. These include high-temperature expansions, duality, Monte Carlo computer simulations, and weak coupling expansions. A #betta#-parameter calculation for asymptotically free-spin models is presented. The Hamiltonian formulation of lattice gauge theory is presented and is illustrated in the context of flux tube dynamics. Roughening transitions, Casimir forces, and the restoration of rotational symmetry are discussed. Mechanisms of confinement in lattice theories are illustrated in the two-dimensional electrodynamics of the planar model and the U(1) gauge theory in four dimensions. Generalized actions for SU(2) gauge theories and the relevance of monopoles and strings to crossover phenomena are considered. A brief discussion of the continuity of fields and topologial charge in asymptotically free lattice models is presented. The final major topic of this review concerns lattice fermions. The species doubling problem and its relation to chiral symmetry are illustrated. Staggered Euclidean fermion methods are discussed in detail, with an emphasis on species counting, remnants of chiral symmetry, Block spin variables, and the axial anomaly. Numerical methods for including fermions in computer simulations are considered. Jacobi and Gauss-Siedel inversion methods to obtain the fermion propagator in a background gauge field are reviewed

463

Real Representation in Chiral Gauge Theories on the Lattice

The Weyl fermion belonging to the real representation of the gauge group provides a simple illustrative example for L\\"uscher'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.

Suzuki, H

2000-01-01

464

Resource Letter: Gravitational Lensing

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

465

Fermions in Gravitation Theory

Digital Repository Infrastructure Vision for European Research (DRIVER)

In gravitation theory, a fermion field must be regarded only in a pair with a certain tetrad gravitational field. These pairs can be represented by sections of the composite spinor bundle $S\\to\\Si\\to X^4$ where values of gravitational fields play the role of parameter coordinates, besides the familiar world coordinates.

Sardanashvily, G.

1995-01-01

466

Digital Repository Infrastructure Vision for European Research (DRIVER)

A special-relativistic scalar-vector theory of gravitation is presented which mimics an important class of solutions of Einstein's gravitational field equations. The theory includes solutions equivalent to Schwarzschild, Kerr, Reissner-Nordstroem, and Friedman metrics as well as to gravitational waves. In fact, all the empirical tests until now due to general relativity can be explained within this flat spacetime theory.

Goenner, H.; Leclerc, M.

2000-01-01

467

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)

468

Detection of gravitational radiation

Energy Technology Data Exchange (ETDEWEB)

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).

Holten, J.W. van [ed.

1994-12-31

469

The trace anomaly and dynamical vacuum energy in cosmology

Energy Technology Data Exchange (ETDEWEB)

The trace anomaly of conformal matter implies the existence of massless scalar poles in physical amplitudes involving the stress-energy tensor. These poles may be described by a local effective action with massless scalar fields, which couple to classical sources, contribute to gravitational scattering processes, and can have long range gravitational effects at macroscopic scales. In an effective field theory approach, the effective action of the anomaly is an infrared relevant term that should be added to the Einstein-Hilbert action of classical General Relativity to take account of macroscopic quantum effects. The additional scalar degrees of freedom contained in this effective action may be understood as responsible for both the Casimir effect in flat spacetime and large quantum backreaction effects at the horizon scale of cosmological spacetimes. These effects of the trace anomaly imply that the cosmological vacuum energy is dynamical, and its value depends on macroscopic boundary conditions at the cosmological horizon scale, rather than sensitivity to the extreme ultraviolet Planck scale.

Mottola, Emil [Los Alamos National Laboratory

2010-01-01

470

Viewing gravitational energy-momentum $p_G^\\mu$ as equal by observation, but different in essence from inertial energy-momentum $p_I^\\mu$ naturally leads to the gauge theory of volume-preserving diffeormorphisms of an inner Minkowski space ${\\bf M}^{\\sl 4}$. To extract its physical content the full gauge group is reduced to its Poincar\\'e subgroup. The respective Poincar\\'e gauge fields, field strengths and Poincar\\'e-covariant field equations are obtained and point-particle source currents are derived. The resulting set of non-linear field equations coupled to point matter is solved in first order resulting in Lienard-Wiechert-like potentials for the Poincar\\'e fields. After numerical identification of gravitational and inertial energy-momentum Newton's inverse square law for gravity in the static non-relativistic limit is recovered. The Weak Equivalence Principle in this approximation is proven to be valid and spacetime geometry in the presence of Poincar\\'e fields is shown to be curved. Finally, the gravit...

Wiesendanger, C

2011-01-01

471

Scale-covariant theory of gravitation and astrophysical applications

A scale-covariant theory of gravitation is presented which is characterized by a set of equations that are complete only after a choice of the scale function is made. Special attention is given to gauge conditions and units which allow gravitational phenomena to be described in atomic units. The generalized gravitational-field equations are derived by performing a direct scale transformation, by extending Riemannian geometry to Weyl geometry through the introduction of the notion of cotensors, and from a variation principle. Modified conservation laws are provided, a set of dynamical equations is obtained, and astrophysical consequences are considered. The theory is applied to examine certain homogeneous cosmological solutions, perihelion shifts, light deflections, secular variations of planetary orbital elements, stellar structure equations for a star in quasi-static equilibrium, and the past thermal history of earth. The possible relation of the scale-covariant theory to gauge field theories and their predictions of cosmological constants is discussed.

Canuto, V.; Adams, P. J.; Hsieh, S.-H.; Tsiang, E.

1977-01-01

472

Introduction to gauge theories

International Nuclear Information System (INIS)

These lecture notes contain the text of five lectures and a Supplement. The lectures were given at the JINR-CERN School of Physics, Tabor, Czechoslovakia, 5-18 June 1983. The subgect of the lecinvariancetures: gauge of electromagnetic and weak interactions, higgs and supersymmetric particles. The Supplement contains reprints (or excerpts) of some classical papers on gauge invariance by V. Fock, F. London, O. Klein and H. Weyl, in which the concept of gauge invariance was introduced and developed

473

High temperature pressure gauge

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

474

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.

475

Anomaly-free version of SU(2)U(1)U(1)/sup '/

International Nuclear Information System (INIS)

The most general anomaly-free version of the SU(2) x U(1) x U(1)' local gauge-invariant model is presented here, for two different Higgs structures (the minimal ones), as an extension of the SU(2) x U(1) Glashow-Weinberg-Salam model

476

Exploring the web of heterotic string theories using anomalies

International Nuclear Information System (INIS)

We investigate how anomalies can be used to infer relations among different descriptions of heterotic string theory. Starting from the observation that the construction mechanism of heterotic orbifold compactifications considered up to now prevents them from being resolved into fully smooth Calabi-Yau compactification manifolds, we use a new mechanism to obtain an orbifold which does not suffer from the aforementioned limitations. We explain in general how to resolve orbifolds into smooth Calabi-Yau using toric geometry and gauged linear sigma models. The latter allow for studying the theory in various other regions of the string moduli space as well, which unveils interesting intermediate geometries. By following anomalies through the different regimes, we can match the orbifold theories to their smooth Calabi-Yau counterparts. In the process, we investigate discrete R and non-R orbifold symmetries and propose a mechanism for studying their fate in other regions of the moduli space. Finally, we introduce a novel anomaly cancelation mechanism in gauged linear sigma models, which manifests itself in target space as a description of compactification geometries with torsion and Neveu-Schwarz five branes.

477

Exploring the web of heterotic string theories using anomalies

Energy Technology Data Exchange (ETDEWEB)

We investigate how anomalies can be used to infer relations among different descriptions of heterotic string theory. Starting from the observation that the construction mechanism of heterotic orbifold compactifications considered up to now prevents them from being resolved into fully smooth Calabi-Yau compactification manifolds, we use a new mechanism to obtain an orbifold which does not suffer from the aforementioned limitations. We explain in general how to resolve orbifolds into smooth Calabi-Yau using toric geometry and gauged linear sigma models. The latter allow for studying the theory in various other regions of the string moduli space as well, which unveils interesting intermediate geometries. By following anomalies through the different regimes, we can match the orbifold theories to their smooth Calabi-Yau counterparts. In the process, we investigate discrete R and non-R orbifold symmetries and propose a mechanism for studying their fate in other regions of the moduli space. Finally, we introduce a novel anomaly cancelation mechanism in gauged linear sigma models, which manifests itself in target space as a description of compactification geometries with torsion and Neveu-Schwarz five branes.

Ruehle, Fabian

2013-07-15

478

Eleven dimensional supergravity in light cone gauge

Light-cone gauge manifestly supersymmetric formulation of eleven dimensional supergravity is developed. The formulation is given entirely in terms of light cone scalar superfield, allowing us to treat all component fields on an equal footing. All higher derivative on mass shell manifestly supersymmetric 4-point functions invariant with respect to linear supersymmetry transformations and corresponding (in gravitational bosonic sector) to terms constructed from four Riemann tensors and derivatives are found. Superspace representation for 4-point scattering amplitudes is also obtained. Superfield representation of linearized interaction vertex of superparticle and supergravity fields is presented. All 4-point higher derivative interaction vertices of ten-dimensional SYM theory are also determined.

Metsaev, R R

2004-01-01

479

In this paper we give a variation of the gauge procedure which employs a scalar gauge field, $B (x)$, in addition to the usual vector gauge field, $A_\\mu (x)$. We study this variant of the usual gauge procedure in the context of a complex scalar, matter field $\\phi (x)$ with a U(1) symmetry. We will focus most on the case when $\\phi$ develops a vacuum expectation value via spontaneous symmetry breaking. We find that under these conditions the scalar gauge field mixes with the Goldstone boson that arises from the breaking of a global symmetry. Some other interesting features of this scalar gauge model are: (i) The new gauge procedure gives rise to terms which violate C and CP symmetries. This may have have applications in cosmology or for CP violation in particle physics; (ii) the existence of mass terms in the Lagrangian which respect the new extended gauge symmetry. Thus one can have gauge field mass terms even in the absence of the usual Higgs mechanism; (iii) the emergence of a sine-Gordon potential for th...

Guendelman, Eduardo I

2014-01-01

480

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