General relativity and gauge gravity theories of higher order

International Nuclear Information System (INIS)

Konopleva, N.P.

1998-01-01

It is a short review of today's gauge gravity theories and their relations with Einstein General Relativity. The conceptions of construction of the gauge gravity theories with higher derivatives are analyzed. GR is regarded as the gauge gravity theory corresponding to the choice of G ∞4 as the local gauge symmetry group and the symmetrical tensor of rank two g μν as the field variable. Using the mathematical technique, single for all fundamental interactions (namely variational formalism for infinite Lie groups), we can obtain Einstein's theory as the gauge theory without any changes. All other gauge approaches lead to non-Einstein theories of gravity. But above-mentioned mathematical technique permits us to construct the gauge gravity theory of higher order (for instance SO (3,1)-gravity) so that all vacuum solutions of Einstein equations are the solutions of the SO (3,1)-gravity theory. The structure of equations of SO(3,1)-gravity becomes analogous to Weeler-Misner geometrodynamics one

BRST operator quantization of generally covariant gauge systems

International Nuclear Information System (INIS)

Ferraro, R.; Sforza, D.M.

1997-01-01

The BRST generator is realized as a Hermitian nilpotent operator for a finite-dimensional gauge system featuring a quadratic super-Hamiltonian and linear supermomentum constraints. As a result, the emerging ordering for the Hamiltonian constraint is not trivial, because the potential must enter the kinetic term in order to obtain a quantization invariant under scaling. Namely, BRST quantization does not lead to the curvature term used in the literature as a means to get that invariance. The inclusion of the potential in the kinetic term, far from being unnatural, is beautifully justified in light of the Jacobi's principle. copyright 1997 The American Physical Society

Degenerate gauge conditions, generalized Gribov's ambiguity and BRST symmetry

International Nuclear Information System (INIS)

Fabbrichesi, M.E.

1987-01-01

The BFS-BRST approach to gauge theories is considered. It is argued that the BRST-invariant boundary conditions ordinarily used do not maintain the necessary degeneracy in the gauge fixing. As a by-product of this discussion, the existence of a generalized Gribov-like ambiguity is suggested. This ambiguity is however shown to be just a particular BRST transformation

Canonical quantization of the generalized axial gauge

International Nuclear Information System (INIS)

Haller, K.

1990-01-01

The incompatibility of the constraint A 3 =0 with canonical commutation rules is discussed. A canonical formulation is given of QED and QCD in the axial gauge with n 1 =n 2 =0, n 3 =α and n 0 =β, where α and β are arbitrary real numbers. A Hilbert space is established for the perturbative theory, and a propagator is derived by obtaining an expression for the interaction picture gauge fields, and evaluating the vacuum expectation value of its time-ordered products in the perturbative vacuum. The propagator is expressed in terms of the parameter γ=α/β and is shown to reproduce the light cone gauge propagator when γ=1, and the temporal gauge propagator when γ=0, accommodating various prescriptions for the spurious propagator pole, including the Mandelstam-Leibbrandt and principal value prescriptions. When γ→∞, the generalized axial gauge propagator leads to an expression for the propagator in the A 3 =0 gauge, though in that case the order in which the integration over k 0 is performed, and the limit γ→∞ is taken, affects the resulting expression. Another Hilbert space is established, in which the constraints that include all interactions are implemented in a time independent fashion. It is pointed out that this Hilbert space, and the Hilbert space of the perturbative theory are unitarily equivalent in QED, but that they cannot be unitarily equivalent in QCD. Implications of this fact for the nonperturbative states of QCD are discussed. (orig.)

On the Generalized Geometry Origin of Noncommutative Gauge Theory

CERN Document Server

Jurco, Branislav; Vysoky, Jan

2013-01-01

We discuss noncommutative gauge theory from the generalized geometry point of view. We argue that the equivalence between the commutative and semiclassically noncommutative DBI actions is naturally encoded in the generalized geometry of D-branes.

Cellular gauge symmetry and the Li organization principle: General considerations.

Science.gov (United States)

Tozzi, Arturo; Peters, James F; Navarro, Jorge; Kun, Wu; Lin, Bi; Marijuán, Pedro C

2017-12-01

Based on novel topological considerations, we postulate a gauge symmetry for living cells and proceed to interpret it from a consistent Eastern perspective: the li organization principle. In our framework, the reference system is the living cell, equipped with general symmetries and energetic constraints standing for the intertwined biochemical, metabolic and signaling pathways that allow the global homeostasis of the system. Environmental stimuli stand for forces able to locally break the symmetry of metabolic/signaling pathways, while the species-specific DNA is the gauge field that restores the global homeostasis after external perturbations. We apply the Borsuk-Ulam Theorem (BUT) to operationalize a methodology in terms of topology/gauge fields and subsequently inquire about the evolution from inorganic to organic structures and to the prokaryotic and eukaryotic modes of organization. We converge on the strategic role that second messengers have played regarding the emergence of a unitary gauge field with profound evolutionary implications. A new avenue for a deeper investigation of biological complexity looms. Philosophically, we might be reminded of the duality between two essential concepts proposed by the great Chinese synthesizer Zhu Xi (in the XIII Century). On the one side the li organization principle, equivalent to the dynamic interplay between symmetry and information; and on the other side the qi principle, equivalent to the energy participating in the process-both always interlinked with each other. In contemporary terms, it would mean the required interconnection between information and energy, and the necessity to revise essential principles of information philosophy. Copyright © 2017 Elsevier Ltd. All rights reserved.

General gauge mediation in five dimensions

International Nuclear Information System (INIS)

McGarrie, Moritz; Russo, Rodolfo

2010-01-01

We use the ''general gauge mediation'' (GGM) formalism to describe a five-dimensional setup with an S 1 /Z 2 orbifold. We first consider a model independent supersymmetry breaking hidden sector on one boundary and generic chiral matter on another. Using the definition of GGM, the effects of the hidden sector are contained in a set of global symmetry current correlator functions and is mediated through the bulk. We find the gaugino, sfermion and hyperscalar mass formulas for minimal and generalized messengers in different regimes of a large, small and intermediate extra dimension. Then we use the five-dimensional GGM formalism to construct a model in which an SU(5) Intriligator, Seiberg and Shih (ISS) model is located on the hidden boundary. We weakly gauge a global symmetry of the ISS model and associate it with the bulk vector superfield. Compared to four-dimensional GGM, there is a natural way to adjust the gaugino versus sfermion mass ratio by a factor (Ml) 2 , where M is a characteristic mass scale of the supersymmetry breaking sector and l is the length of the extra dimension.

On the structure of generalized monopole solutions in gauge-theories

International Nuclear Information System (INIS)

Horvath, Z.; Palla, L.

1976-01-01

A method is presented for constructing generalized 't Hooft monopole solutions in a gauge theory with an arbitrary gauge group. Restrictions arising from the condition of finite energy are derived. The radial oscillation of the solution is discussed. Using this method all the SU(3) solutions known in the literature are reproduced. Finite energy monopoles possessing magnetic charge in the range g 0 0 0 are found in SU(N) gauge theories. Different charge quantization conditions are analyzed to understand the structure of the solutions. (Auth.)

Generalized operator canonical formalism and gauge invariance

International Nuclear Information System (INIS)

Fradkina, T.E.

1988-01-01

A direct proof is given in the functional representation of the invariance of the S-matrix constructed in the framework of the generalized operator canonical formalism. We find the traditional functional expression for the S-matrix (without point-splitting in the time factor) in the generalized phase space, as well as in the ghost configuration space. An explicit expression is obtained for the effective unitarizing Hamiltonian for gauge theories with constraints of arbitrary rank

Generalized messenger sector for gauge mediation of supersymmetry breaking and the soft spectrum

International Nuclear Information System (INIS)

Marques, Diego

2009-01-01

We consider a generic renormalizable and gauge invariant messenger sector and derive the sparticle mass spectrum using the formalism introduced for General Gauge Mediation. Our results recover many expressions found in the literature in various limits. Constraining the messenger sector with a global symmetry under which the spurion field is charged, we analyze Extraordinary Gauge Mediation beyond the small SUSY breaking limit. Finally, we include D-term contributions and compute their corrections to the soft masses. This leads to a perturbative framework allowing to explore models capable of fully covering the parameter space of General Gauge Mediation to the Supersymmetric Standard Model.

A Generalized Yang-Mills Model and Dynamical Breaking of Gauge Symmetry

International Nuclear Information System (INIS)

Wang Dianfu; Song Heshan

2005-01-01

A generalized Yang-Mills model, which contains, besides the vector part V μ , also a scalar part S, is constructed and the dynamical breaking of gauge symmetry in the model is also discussed. It is shown, in terms of Nambu-Jona-Lasinio (NJL) mechanism, that the gauge symmetry breaking can be realized dynamically in the generalized Yang-Mills model. The combination of the generalized Yang-Mills model and the NJL mechanism provides a way to overcome the difficulties related to the Higgs field and the Higgs mechanism in the usual spontaneous symmetry breaking theory.

A general theory for gauge-free lifting

International Nuclear Information System (INIS)

Morrison, P. J.

2013-01-01

A theory for lifting equations of motion for charged particle dynamics, subject to given electromagnetic like forces, up to a gauge-free system of coupled Hamiltonian Vlasov-Maxwell like equations is given. The theory provides very general expressions for the polarization and magnetization vector fields in terms of the particle dynamics description of matter. Thus, as is common in plasma physics, the particle dynamics replaces conventional constitutive relations for matter. Several examples are considered including the usual Vlasov-Maxwell theory, a guiding center kinetic theory, Vlasov-Maxwell theory with the inclusion of spin, and a Vlasov-Maxwell theory with the inclusion of Dirac's magnetic monopoles. All are shown to be Hamiltonian field theories and the Jacobi identity is proven directly.

Membrane models and generalized Z2 gauge theories

International Nuclear Information System (INIS)

Lowe, M.J.; Wallace, D.J.

1980-01-01

We consider models of (d-n)-dimensional membranes fluctuating in a d-dimensional space under the action of surface tension. We investigate the renormalization properties of these models perturbatively and in 1/n expansion. The potential relationships of these models to generalized Z 2 gauge theories are indicated. (orig.)

Generalized string theory mapping relations between gravity and gauge theory

International Nuclear Information System (INIS)

Bjerrum-Bohr, N.E.J.

2003-01-01

A previous study of the Kawai, Lewellen and Tye (KLT) relations between gravity and gauge theories, imposed by the relationship of closed and open strings, are here extended in the light of general relativity and Yang-Mills theory as effective field theories. We discuss the possibility of generalizing the traditional KLT mapping in this effective setting. A generalized mapping between the effective Lagrangians of gravity and Yang-Mills theory is presented, and the corresponding operator relations between gauge and gravity theories at the tree level are further explored. From this generalized mapping remarkable diagrammatic relations are found, linking diagrams in gravity and Yang-Mills theory, as well as diagrams in pure effective Yang-Mills theory. Also the possibility of a gravitational coupling to an antisymmetric field in the gravity scattering amplitude is considered, and shown to allow for mixed open-closed string solutions, i.e., closed heterotic strings

Pure General Gauge Mediation for Early LHC Searches

CERN Document Server

Abel, Steven; Jaeckel, Joerg; Khoze, Valentin V

2010-01-01

We present benchmark points for Pure General Gauge Mediation (GGM) models specifically optimised for early LHC searches. The pure GGM set-up is as defined in our previous paper arXiv:0910.2674: namely we adopt the minimal set-up in which B_mu is generated only through gauge interactions, and as a result tan beta is a prediction rather than an input. The only input parameters are messenger masses together with two independent scales which generate gaugino and scalar masses. The parameter space favoured by current experimental data includes an interesting region with light gluinos (m_g 2 cross-sections. This data in SLHA format can be found at http://www.ippp.dur.ac.uk/~SUSY

Maximally Generalized Yang-Mills Model and Dynamical Breaking of Gauge Symmetry

International Nuclear Information System (INIS)

Wang Dianfu; Song Heshan

2006-01-01

A maximally generalized Yang-Mills model, which contains, besides the vector part V μ , also an axial-vector part A μ , a scalar part S, a pseudoscalar part P, and a tensor part T μν , is constructed and the dynamical breaking of gauge symmetry in the model is also discussed. It is shown, in terms of the Nambu-Jona-Lasinio mechanism, that the gauge symmetry breaking can be realized dynamically in the maximally generalized Yang-Mills model. The combination of the maximally generalized Yang-Mills model and the NJL mechanism provides a way to overcome the difficulties related to the Higgs field and the Higgs mechanism in the usual spontaneous symmetry breaking theory.

Gauge-invariant dynamical quantities of QED with decomposed gauge potentials

International Nuclear Information System (INIS)

Zhou Baohua; Huang Yongchang

2011-01-01

We discover an inner structure of the QED system; i.e., by decomposing the gauge potential into two orthogonal components, we obtain a new expansion of the Lagrangian for the electron-photon system, from which, we realize the orthogonal decomposition of the canonical momentum conjugate to the gauge potential with the canonical momentum's two components conjugate to the gauge potential's two components, respectively. Using the new expansion of Lagrangian and by the general method of field theory, we naturally derive the gauge invariant separation of the angular momentum of the electron-photon system from Noether theorem, which is the rational one and has the simplest form in mathematics, compared with the other four versions of the angular momentum separation available in literature. We show that it is only the longitudinal component of the gauge potential that is contained in the orbital angular momentum of the electron, as Chen et al. have said. A similar gauge invariant separation of the momentum is given. The decomposed canonical Hamiltonian is derived, from which we construct the gauge invariant energy operator of the electron moving in the external field generated by a proton [Phys. Rev. A 82, 012107 (2010)], where we show that the form of the kinetic energy containing the longitudinal part of the gauge potential is due to the intrinsic requirement of the gauge invariance. Our method provides a new perspective to look on the nucleon spin crisis and indicates that this problem can be solved strictly and systematically.

Nonlinear Dynamics, Fixed Points and Coupled Fixed Points in Generalized Gauge Spaces with Applications to a System of Integral Equations

Directory of Open Access Journals (Sweden)

Adrian Petruşel

2015-01-01

Full Text Available We will discuss discrete dynamics generated by single-valued and multivalued operators in spaces endowed with a generalized metric structure. More precisely, the behavior of the sequence (fn(xn∈N of successive approximations in complete generalized gauge spaces is discussed. In the same setting, the case of multivalued operators is also considered. The coupled fixed points for mappings t1:X1×X2→X1 and t2:X1×X2→X2 are discussed and an application to a system of nonlinear integral equations is given.

General mirror pairs for gauged linear sigma models

Energy Technology Data Exchange (ETDEWEB)

Aspinwall, Paul S.; Plesser, M. Ronen [Departments of Mathematics and Physics, Duke University,Box 90320, Durham, NC 27708-0320 (United States)

2015-11-05

We carefully analyze the conditions for an abelian gauged linear σ-model to exhibit nontrivial IR behavior described by a nonsingular superconformal field theory determining a superstring vacuum. This is done without reference to a geometric phase, by associating singular behavior to a noncompact space of (semi-)classical vacua. We find that models determined by reflexive combinatorial data are nonsingular for generic values of their parameters. This condition has the pleasant feature that the mirror of a nonsingular gauged linear σ-model is another such model, but it is clearly too strong and we provide an example of a non-reflexive mirror pair. We discuss a weaker condition inspired by considering extremal transitions, which is also mirror symmetric and which we conjecture to be sufficient. We apply these ideas to extremal transitions and to understanding the way in which both Berglund-Hübsch mirror symmetry and the Vafa-Witten mirror orbifold with discrete torsion can be seen as special cases of the general combinatorial duality of gauged linear σ-models. In the former case we encounter an example showing that our weaker condition is still not necessary.

General mirror pairs for gauged linear sigma models

International Nuclear Information System (INIS)

Aspinwall, Paul S.; Plesser, M. Ronen

2015-01-01

We carefully analyze the conditions for an abelian gauged linear σ-model to exhibit nontrivial IR behavior described by a nonsingular superconformal field theory determining a superstring vacuum. This is done without reference to a geometric phase, by associating singular behavior to a noncompact space of (semi-)classical vacua. We find that models determined by reflexive combinatorial data are nonsingular for generic values of their parameters. This condition has the pleasant feature that the mirror of a nonsingular gauged linear σ-model is another such model, but it is clearly too strong and we provide an example of a non-reflexive mirror pair. We discuss a weaker condition inspired by considering extremal transitions, which is also mirror symmetric and which we conjecture to be sufficient. We apply these ideas to extremal transitions and to understanding the way in which both Berglund-Hübsch mirror symmetry and the Vafa-Witten mirror orbifold with discrete torsion can be seen as special cases of the general combinatorial duality of gauged linear σ-models. In the former case we encounter an example showing that our weaker condition is still not necessary.

Gauge bridges in classical field theory

International Nuclear Information System (INIS)

Jakobs, S.

2009-03-01

In this thesis Poisson structures of two classical gauge field theories (Maxwell-Klein-Gordon- and Maxwell-Dirac-system) are constructed using the parametrix construction of Green's functions. Parametrices for the Maxwell-Klein-Gordon- and Maxwell-Dirac-system are constructed in Minkowski space and this construction is later generalized to curved space times for the Maxwell-Klein-Gordon-system. With these Green's functions Poisson brackets will be defined as Peierls brackets. Finally non-local, gauge invariant observables, the so-called ''gauge bridges''are constructed. Gauge bridges are the matrix elements of holonomy operators. It is shown, that these emerge from Poisson brackets of local, gauge invariant observables. (orig.)

The geometry of the SLsub(2,c) gauge formulation of general relativity

International Nuclear Information System (INIS)

Kaye, M.

1978-01-01

The formulation of Einstein's general theory of relativity as an SLsub(2,c) gauge theory is considered. Use is made of the language of fibre bundles and general arguments are put forward in favour of the SLsub(2,c) approach to problems connected with the study of the space-time structure. The possibility of deriving the dynamics of the theory from a Yang-Mills-type Lagrangian density is discussed. Finally, the spinor approach is compared with other approaches to the problem of formulating Einstein's theory as a gauge theory

Derivation of the gauge link in light cone gauge

International Nuclear Information System (INIS)

Gao Jianhua

2010-01-01

In light cone gauge, a gauge link at light cone infinity is necessary for transverse momentum-dependent parton distribution to restore the gauge invariance in some specific boundary conditions. We derive such transverse gauge link in a more regular and general method. We find the gauge link at light cone infinity naturally arises from the contribution of the pinched poles: one is from the quark propagator and the other is hidden in the gauge vector field in light cone gauge. Actually, in the amplitude level, we have obtained a more general gauge link over the hypersurface at light cone infinity which is beyond the transverse direction. The difference of such gauge link between semi-inclusive deep inelastic scattering and Drell-Yan processes can also be obtained directly and clearly in our derivation.

Generalization of trinification to theories with 3N SU(3) gauge groups

International Nuclear Information System (INIS)

Carone, Christopher D.

2005-01-01

We consider a natural generalization of trinification to theories with 3N SU(3) gauge groups. These theories have a simple moose representation and a gauge boson spectrum that can be interpreted via the deconstruction of a 5D theory with unified symmetry broken on a boundary. Although the matter and Higgs sectors of the theory have no simple extra-dimensional analog, gauge unification retains features characteristic of the 5D theory. We determine possible assignments of the matter and Higgs fields to unified multiplets and present theories that are viable alternatives to minimal trinified GUTs

Canonical transformation path to gauge theories of gravity

Science.gov (United States)

Struckmeier, J.; Muench, J.; Vasak, D.; Kirsch, J.; Hanauske, M.; Stoecker, H.

2017-06-01

In this paper, the generic part of the gauge theory of gravity is derived, based merely on the action principle and on the general principle of relativity. We apply the canonical transformation framework to formulate geometrodynamics as a gauge theory. The starting point of our paper is constituted by the general De Donder-Weyl Hamiltonian of a system of scalar and vector fields, which is supposed to be form-invariant under (global) Lorentz transformations. Following the reasoning of gauge theories, the corresponding locally form-invariant system is worked out by means of canonical transformations. The canonical transformation approach ensures by construction that the form of the action functional is maintained. We thus encounter amended Hamiltonian systems which are form-invariant under arbitrary spacetime transformations. This amended system complies with the general principle of relativity and describes both, the dynamics of the given physical system's fields and their coupling to those quantities which describe the dynamics of the spacetime geometry. In this way, it is unambiguously determined how spin-0 and spin-1 fields couple to the dynamics of spacetime. A term that describes the dynamics of the "free" gauge fields must finally be added to the amended Hamiltonian, as common to all gauge theories, to allow for a dynamic spacetime geometry. The choice of this "dynamics" Hamiltonian is outside of the scope of gauge theory as presented in this paper. It accounts for the remaining indefiniteness of any gauge theory of gravity and must be chosen "by hand" on the basis of physical reasoning. The final Hamiltonian of the gauge theory of gravity is shown to be at least quadratic in the conjugate momenta of the gauge fields—this is beyond the Einstein-Hilbert theory of general relativity.

Quark confinement and the short-range component of general affine gauge gravity

International Nuclear Information System (INIS)

Sijacki, D.

1982-01-01

Within the framework of a gauge field theory based on the general affine space-time symmetry, we propose a certain purely quadratic gauge field lagrangian. In the large-scale region it yields an Einstein-Cartan-like gravity with Newton's constand generated spontaneously, while in the particle domain it yields a renormalizable theory with a confining potential applying to quarks and not to leptons. (orig.)

Design of control system for profile gauge

International Nuclear Information System (INIS)

Huang Yibin; Zhang Yu'ai

2013-01-01

The profile gauge can on-line get the cross section in the steel strip, so it has been widely used in hot continuous rolling production-line. The structure of profile gauge and its distributed hardware structure based on PLC and software design of its control subsystem were introduced. The method of temperature and humidity measurement was analyzed. The time response of X-ray machine control based on RS232 communication was researched. It is proved that the control system meets the requirements of the profile gauge system. (authors)

Systematics of higher-spin gauge fields

International Nuclear Information System (INIS)

de Wit, B.; Freedman, D.Z.

1980-01-01

Free-field theories for symmetric tensor and tensor-spinor gauge fields have recently been obtained which describe massless particles of arbitrary integer or half-integer spin. An independent discussion of these field theories is given here, based on a hierarchy of generalized Christoffel symbols with simple gauge transformation properties. The necessity of certain constraints on gauge fields and parameters is easily seen. Wave equations and Lagrangians are expressed in terms of the Christoffel symbols, and the independent modes of the system are counted in covariant gauges. Minimal-coupling inconsistency and a combined system of higher-spin boson gauge fields interacting with relativistic particles is discussed

Four-dimensional Ashkin-Teller gauge theory

International Nuclear Information System (INIS)

Alcaraz, F.C.; Jacobs, L.

1983-01-01

The authors construct and analyze a lattice field theory of two Z 2 gauge fields which interact in a minimal gauge-invariant fashion. Although the theory presented here, a generalization of the two-dimensional Ashkin-Teller spin system, has no formal continuum limit, it is found that it has an electrodynamicslike phase similar to that observed in general Z/sub N/ theories for N> or =4. This model is probably the simplest generalization of the conventional Z 2 pure gauge theory which has a massless phase separated from the strong- and weak-coupling regions by lines of second-order phase transitions

Lectures on quantization of gauge systems

NARCIS (Netherlands)

Reshetikhin, N.; Booß-Bavnbek, B.; Esposito, G.; Lesch, M.

2010-01-01

A gauge system is a classical field theory where among the fields there are connections in a principal G-bundle over the space - time manifold and the classical action is either invariant or transforms appropriately with respect to the action of the gauge group. The lectures are focused on the path

General relativity from a gauged Wess-Zumino-Witten term

International Nuclear Information System (INIS)

Anabalon, Andres; Willison, Steven; Zanelli, Jorge

2007-01-01

In this paper two things are done. First it is shown how a four-dimensional gauged Wess-Zumino-Witten term arises from the five-dimensional Einstein-Hilbert plus Gauss-Bonnet Lagrangian with a special choice of the coefficients. Second, the way in which the equations of motion of four-dimensional General Relativity arise is exhibited

Global gauge fixing in lattice gauge theories

Energy Technology Data Exchange (ETDEWEB)

Fachin, S.; Parrinello, C. (Physics Department, New York University, 4 Washington Place, New York, New York (USA))

1991-10-15

We propose a covariant, nonperturbative gauge-fixing procedure for lattice gauge theories that avoids the problem of Gribov copies. This is closely related to a recent proposal for a gauge fixing in the continuum that we review. The lattice gauge-fixed model allows both analytical and numerical investigations: on the analytical side, explicit nonperturbative calculations of gauge-dependent quantities can be easily performed in the framework of a generalized strong-coupling expansion, while on the numerical side a stochastic gauge-fixing algorithm is very naturally associated with the scheme. In both applications one can study the gauge dependence of the results, since the model actually provides a smooth'' family of gauge-fixing conditions.

Generalized Coulomb gauge without Gribov ambiguity

Energy Technology Data Exchange (ETDEWEB)

Fachin, S.; Parrinello, C. (New York Univ., NY (United States). Physics Dept.)

1992-05-01

We discuss a global gauge-fixing prescription that is free of the Gribov problem, preserves reflection positivity and contains as a limiting case the (maximal) Coulomb gauge. In such a formalism it is very easy to check that only color singlet states propagate in Euclidean time, for any value of [beta]. (orig.).

Gauge theory for finite-dimensional dynamical systems

International Nuclear Information System (INIS)

Gurfil, Pini

2007-01-01

Gauge theory is a well-established concept in quantum physics, electrodynamics, and cosmology. This concept has recently proliferated into new areas, such as mechanics and astrodynamics. In this paper, we discuss a few applications of gauge theory in finite-dimensional dynamical systems. We focus on the concept of rescriptive gauge symmetry, which is, in essence, rescaling of an independent variable. We show that a simple gauge transformation of multiple harmonic oscillators driven by chaotic processes can render an apparently ''disordered'' flow into a regular dynamical process, and that there exists a strong connection between gauge transformations and reduction theory of ordinary differential equations. Throughout the discussion, we demonstrate the main ideas by considering examples from diverse fields, including quantum mechanics, chemistry, rigid-body dynamics, and information theory

Dualiy for Z(N) gauge theories

International Nuclear Information System (INIS)

Korthals Altes, C.P.

1978-04-01

The duality properties of simple Z(N) gauge theories are discussed. For N 4 these systems are not self dual. Also the order parameter is discussed. The general Z(N) gauge theory is found to be self dual for all N

Algebraic quantization of systems with a gauge degeneracy

International Nuclear Information System (INIS)

Grundling, H.B.G.S.; Hurst, C.A.

1985-01-01

Systems with a gauge degeneracy are characterized either by supplementary conditions, or by a set of generators of gauge transformations, or by a set of constraints deriving from Dirac's canonical constraint method. These constraints can be expressed either as conditions on the field algebra F, or on the states on F. In a Csup(*)-algebra framework, we show that the state conditions give rise to a factor algebra of a subalgebra of the field algebra F. This factor algebra R, is free of state conditions. In this formulation we show also that the algebraic conditions can be treated in the same way as the state conditions. The connection between states on F and states on R is investigated further within this framework, as is also the set of transformations which are compatible with the set of constraints. It is also shown that not every set of constraints can give rise to a nontrivial system. Finally as an example, the abstract theory is applied to the electromagnetic field, and this treatment can be generalized to all systems of bosons with linear constraints. The question of dynamics is not discussed. (orig.)

Gauge glass

International Nuclear Information System (INIS)

Nielsen, H.B.; Brene, N.

1984-12-01

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 SU 5 -breaking in the context of the first breakdown mechanism (D. Bennett, E. Buturovic and H. B. Nielsen) is shortly reviewed. (orig.)

Duality for Z(N) gauge theories

International Nuclear Information System (INIS)

Korthals Altes, C.P.

1978-01-01

The duality properties of simple Z(N) gauge theories are discussed. For N 4 these systems are not self dual. Also, the order parameter is discussed. The general Z(N) gauge theory is found to be self dual for all N. (Auth.)

Gauge-fixing parameter dependence of two-point gauge-variant correlation functions

International Nuclear Information System (INIS)

Zhai, C.

1996-01-01

The gauge-fixing parameter ξ dependence of two-point gauge-variant correlation functions is studied for QED and QCD. We show that, in three Euclidean dimensions, or for four-dimensional thermal gauge theories, the usual procedure of getting a general covariant gauge-fixing term by averaging over a class of covariant gauge-fixing conditions leads to a nontrivial gauge-fixing parameter dependence in gauge-variant two-point correlation functions (e.g., fermion propagators). This nontrivial gauge-fixing parameter dependence modifies the large-distance behavior of the two-point correlation functions by introducing additional exponentially decaying factors. These factors are the origin of the gauge dependence encountered in some perturbative evaluations of the damping rates and the static chromoelectric screening length in a general covariant gauge. To avoid this modification of the long-distance behavior introduced by performing the average over a class of covariant gauge-fixing conditions, one can either choose a vanishing gauge-fixing parameter or apply an unphysical infrared cutoff. copyright 1996 The American Physical Society

Global aspects of gauge anomalies

International Nuclear Information System (INIS)

Zhang, H.

1988-01-01

This dissertation discusses the global aspects of gauge anomalies in even dimensions. After a very brief description of local gauge anomalies, the possible global gauge anomalies for various gauge theories are discussed using homotopy theory. One of the main results obtained in a general formula for the SU(n - k) global gauge anomaly coefficient in arbitrary 2n dimensions. The result is expressed in terms of the James number of the Stiefel manifold SU(n + 1)/SU(n - k) and the generalized Dynkin indices. From this, the possibilities of SU(n), SU(n - 1), and SU(2) global gauge anomalies in arbitrary 2n dimensions have been determined. We have also determined the possibilities of global gauge anomalies for the gauge groups SP(2N) and SO(N) in certain general dimensions, as well as for the exceptional gauge groups in specific dimensions. Moreover, several general propositions are formulated and proved which are very useful in the study of global gauge anomalies

Lagrangian formalism for constrained systems. 2. Gauge symmetries

International Nuclear Information System (INIS)

Pyatov, P.N.

1990-01-01

Using the Lagrangian formalism for constrained systems all gauge symmetries peculiar for a given Lagrangian system and in establishing the relation between them and the constraints are constructed. Besides, the question about the possible dependence of gauge transformations on accelerations and other higher order time derivatives of coordinates is clarified. 14 refs

Technical data on nucleonic gauges

International Nuclear Information System (INIS)

2005-07-01

This nucleonic gauge manual and directory provides a reference database of nucleonic control systems available to potential users in the fields of exploration, exploitation and processing of natural resources and in the manufacturing industries. It starts with background information an the general principals of nucleonic gauges, followed by portable nuclear analysis systems (PNAS), computer tomography, cost-benefit on NCS (Nucleonic Control Systems) applications and trends and transfer of NCS technology. It continues with radiation protection and safety, discusses nucleonic gauges with low radioactivity sources and ends with typical models of nucleonic gauges. The basic principles of the most popular techniques are reviewed and reference data links to suppliers are provided. Information sheets on many typical commercial devices are also included. It will help end-users to select the most suitable alternative to solve a particular problem or to measure a certain parameter in a specific process

Semi-automated x-ray gauging process control system

International Nuclear Information System (INIS)

Draut, C.F.; Homan, D.A.

1976-01-01

An x-ray gauging method was developed and a production gauging system was subsequently fabricated to control the quality of precision manufactured components. The gauging system measures via x-ray absorption the density of pressed finely divided solids held in a dissimilar container. The two dissimilar materials condition necessitated a ''two scan'' technique: first, the x-ray attenuation (absorption) of the empty container prior to loading and then, the attenuation of the loaded container are measured; that is, four variables. The system provided greatly improved product control via timely data feedback and increased product quality assurance via 100 percent inspection of product. In addition, it reduced labor costs, product cost, and possibilities for human errors

Gauge invariance rediscovered

International Nuclear Information System (INIS)

Moriyasu, K.

1978-01-01

A pedagogical approach to gauge invariance is presented which is based on the analogy between gauge transformations and relativity. By using the concept of an internal space, purely geometrical arguments are used to teach the physical ideas behind gauge invariance. Many of the results are applicable to general gauge theories

Gauge Invariance and Frame Independence in Cosmology

NARCIS (Netherlands)

Weenink, J.G.

2013-01-01

In this thesis the mathematical formulation of cosmological perturbations is studied. First we discuss the gauge problem of general relativity: perturbations of the metric and matter fields in an expanding universe are dependent on the choice of coordinate system, i.e. gauge dependent, even though

On behaviour of Weyl's gauge field

International Nuclear Information System (INIS)

Yuan Zhong Zhang.

1990-05-01

We consider a system, consisting of a metric tensor g μυ , a scalar field φ, a Weyl's gauge field A μ and a scalar matter field Φ, which is invariant under general coordinate transformation and Weyl's gauge transformation. Two kinds of identities and field equations are given and discussed. A special space-time with g μυ =φ -2 η μυ is considered in a gauge-independent manner. We point out that in a correct treatment where g μυ is not regarded as an independent variable, an auxiliary condition for Weyl's gauge field cannot be obtained. Therefore Weyl's gauge field can be treated as a usual field of positive norm. (author). 11 refs

Generalized Killing-Yano equations in D=5 gauged supergravity

International Nuclear Information System (INIS)

Kubiznak, David; Kunduri, Hari K.; Yasui, Yukinori

2009-01-01

We propose a generalization of the (conformal) Killing-Yano equations relevant to D=5 minimal gauged supergravity. The generalization stems from the fact that the dual of the Maxwell flux, the 3-form *F, couples naturally to particles in the background as a 'torsion'. Killing-Yano tensors in the presence of torsion preserve most of the properties of the standard Killing-Yano tensors - exploited recently for the higher-dimensional rotating black holes of vacuum gravity with cosmological constant. In particular, the generalized closed conformal Killing-Yano 2-form gives rise to the tower of generalized closed conformal Killing-Yano tensors of increasing rank which in turn generate the tower of Killing tensors. An example of a generalized Killing-Yano tensor is found for the Chong-Cvetic-Lue-Pope black hole spacetime [Z.W. Chong, M. Cvetic, H. Lu, C.N. Pope, (hep-th/0506029)]. Such a tensor stands behind the separability of the Hamilton-Jacobi, Klein-Gordon, and Dirac equations in this background.

On the equivalence of vacuum equations of gauge quadratic theory of gravity and general relativity theory

International Nuclear Information System (INIS)

Zhitnikov, V.V.; Ponomarev, V.N.

1986-01-01

An attempt is made to compare the solution of field equations, corresponding to quadratic equations for the fields (g μν , Γ μν α ) in gauge gravitation theory (GGT) with general relativity theory solutions. Without restrictions for a concrete type of metrics only solutions of equations, for which torsion turns to zero, are considered. Equivalence of vacuum equations of gauge quadratic theory of gravity and general relativity theory is proved using the Newman-Penrose formalism

Self-dual gauge theories

International Nuclear Information System (INIS)

Zet, G.

2002-01-01

The self-duality equations are important in gauge theories because they show the connection between gauge models with internal symmetry groups and gauge theory of gravity. They are differential equations of the first order and it is easier to investigate the solutions for different particular configurations of the gauge fields and of space-times.One of the most important property of the self-duality equations is that they imply the Yang-Mills field equations. In this paper we will prove this property for the general case of a gauge theory with compact Lie group of symmetry over a 4-dimensional space-time manifold. It is important to remark that there are 3m independent self-duality equations (of the first order) while the number of Yang-Mills equations is equal to 4m, where m is the dimension of the gauge group. Both of them have 4m unknown functions which are the gauge potentials A μ a (x), a = 1, 2, ....,m; μ = 0, 1, 2, 3. But, we have, in addition, m gauge conditions for A μ a (x), (for example Coulomb, Lorentz or axial gauge) which together with the selfduality equation constitute a system of 4m equations. The Bianchi identities for the self-dual stress tensor F μν a coincide with the Yang-Mills equations and do not imply therefore supplementary conditions. We use the axial gauge in order to obtain the self duality equations for a SU(2) gauge theory over a curved space-time. The compatibility between self-duality and Yang-Mills equations is studied and some classes of solutions are obtained. In fact, we will write the Einstein-Yang-Mills equations and we will analyse only the Yang-Mills sector. The Einstein equations can not be obtained of course from self-duality. They should be obtained if we would consider a gauge theory having P x SU(2) as symmetry group, where P is the Poincare group. More generally, a gauge theory of N-extended supersymmetry can be developed by imposing the self-duality condition. (author)

Towards the five-loop beta function for a general gauge group

International Nuclear Information System (INIS)

Luthe, Thomas; Schroeder, York

2016-06-01

We present analytical results for the N"4_f and N"3_f terms of the five-loop beta function, for a general gauge group. While the former term agrees with results available from large-N_f studies, the latter is new and extends the value known for SU(3) from an independent calculation.

Baryonic Force for Accelerated Cosmic Expansion and Generalized U1b Gauge Symmetry in Particle-Cosmology

Directory of Open Access Journals (Sweden)

Khan Mehbub

2018-01-01

Full Text Available Based on baryon charge conservation and a generalized Yang-Mills symmetry for Abelian (and non-Abelian groups, we discuss a new baryonic gauge field and its linear potential for two point-like baryon charges. The force between two point-like baryons is repulsive, extremely weak and independent of distance. However, for two extended baryonic systems, we have a dominant linear force α r. Thus, only in the later stage of the cosmic evolution, when two baryonic galaxies are separated by an extremely large distance, the new repulsive baryonic force can overcome the gravitational attractive force. Such a model provides a gauge-field-theoretic understanding of the late-time accelerated cosmic expansion. The baryonic force can be tested by measuring the accelerated Wu-Doppler frequency shifts of supernovae at different distances.

Abelian gauge theories with tensor gauge fields

International Nuclear Information System (INIS)

Kapuscik, E.

1984-01-01

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

Gauge invariance and Weyl-polymer quantization

CERN Document Server

Strocchi, Franco

2016-01-01

The book gives an introduction to Weyl non-regular quantization suitable for the description of physically interesting quantum systems, where the traditional Dirac-Heisenberg quantization is not applicable.  The latter implicitly assumes that the canonical variables describe observables, entailing necessarily the regularity of their exponentials (Weyl operators). However, in physically interesting cases -- typically in the presence of a gauge symmetry -- non-observable canonical variables are introduced for the description of the states, namely of the relevant representations of the observable algebra. In general, a gauge invariant ground state defines a non-regular representation of the gauge dependent Weyl operators, providing a mathematically consistent treatment of familiar quantum systems -- such as the electron in a periodic potential (Bloch electron), the Quantum Hall electron, or the quantum particle on a circle -- where the gauge transformations are, respectively, the lattice translations, the magne...

Introduction to gauge theories

International Nuclear Information System (INIS)

Wit, B. de

1983-01-01

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)

Solution of quantum integrable systems from quiver gauge theories

Energy Technology Data Exchange (ETDEWEB)

Dorey, Nick [Department of Applied Mathematics and Theoretical Physics, University of Cambridge,Cambridge (United Kingdom); Zhao, Peng [Simons Center for Geometry and Physics, Stony Brook University,Stony Brook (United States)

2017-02-23

We construct new integrable systems describing particles with internal spin from four-dimensional N = 2 quiver gauge theories. The models can be quantized and solved exactly using the quantum inverse scattering method and also using the Bethe/Gauge correspondence.

Hermitian (ϵ,δ)-Freudenthal-Kantor Triple Systems and Certain Applications of *-Generalized Jordan Triple Systems to Field Theory

International Nuclear Information System (INIS)

Kamiya, Noriaki; Sato, Matsuo

2014-01-01

We define Hermitian (ϵ,δ)-Freudenthal-Kantor triple systems and prove a structure theorem. We also give some examples of triple systems that are generalizations of the u(N)⊕u(M) and sp(2N)⊕u(1) Hermitian 3-algebras. We apply a *-generalized Jordan triple system to a field theory and obtain a Chern-Simons gauge theory. We find that the novel Higgs mechanism works, where the Chern-Simons gauge theory reduces to a Yang-Mills theory in a certain limit

Inflationary dynamics of kinetically-coupled gauge fields

DEFF Research Database (Denmark)

Ferreira, Ricardo J. Z.; Ganc, Jonathan

2015-01-01

We investigate the inflationary dynamics of two kinetically-coupled massless U(1) gauge fields with time-varying kinetic-term coefficients. Ensuring that the system does not have strongly coupled regimes shrinks the parameter space. Also, we further restrict ourselves to systems that can be quant......We investigate the inflationary dynamics of two kinetically-coupled massless U(1) gauge fields with time-varying kinetic-term coefficients. Ensuring that the system does not have strongly coupled regimes shrinks the parameter space. Also, we further restrict ourselves to systems that can...... be quantized using the standard creation, annihilation operator algebra. This second constraint limits us to scenarios where the system can be diagonalized into the sum of two decoupled, massless, vector fields with a varying kinetic-term coefficient. Such a system might be interesting for magnetogenesis...... because of how the strong coupling problem generalizes. We explore this idea by assuming that one of the gauge fields is the Standard Model U(1) field and that the other dark gauge field has no particles charged under its gauge group. We consider whether it would be possible to transfer a magnetic field...

Gauge theories

International Nuclear Information System (INIS)

Kenyon, I.R.

1986-01-01

Modern theories of the interactions between fundamental particles are all gauge theories. In the case of gravitation, application of this principle to space-time leads to Einstein's theory of general relativity. All the other interactions involve the application of the gauge principle to internal spaces. Electromagnetism serves to introduce the idea of a gauge field, in this case the electromagnetic field. The next example, the strong force, shows unique features at long and short range which have their origin in the self-coupling of the gauge fields. Finally the unification of the description of the superficially dissimilar electromagnetic and weak nuclear forces completes the picture of successes of the gauge principle. (author)

General study of ground states in gauged N=2 supergravity theories with symmetric scalar manifolds in 5 dimensions

International Nuclear Information System (INIS)

Oegetbil, O.

2007-01-01

After reviewing the existing results we give an extensive analysis of the critical points of the potentials of the gauged N=2 Yang-Mills/Einstein supergravity theories coupled to tensor multiplets and hypermultiplets. Our analysis includes all the possible gaugings of all N=2 Maxwell-Einstein supergravity theories whose scalar manifolds are symmetric spaces. In general, the scalar potential gets contributions from R-symmetry gauging, tensor couplings, and hypercouplings. We show that the coupling of a hypermultiplet into a theory whose potential has a nonzero value at its critical point, and gauging a compact subgroup of the hyperscalar isometry group will only rescale the value of the potential at the critical point by a positive factor, and therefore will not change the nature of an existing critical point. However this is not the case for noncompact SO(1,1) gaugings. An SO(1,1) gauging of the hyperisometry will generally lead to de Sitter vacua, which is analogous to the ground states found by simultaneously gauging SO(1,1) symmetry of the real scalar manifold with U(1) R in earlier literature. SO(m,1) gaugings with m>1, which give contributions to the scalar potential only in the magical Jordan family theories, on the other hand, do not lead to de Sitter vacua. Anti-de Sitter vacua are generically obtained when the U(1) R symmetry is gauged. We also show that it is possible to embed certain generic Jordan family theories into the magical Jordan family preserving the nature of the ground states. However the magical Jordan family theories have additional ground states which are not found in the generic Jordan family theories

On the gauge symmetries of Maxwell-like higher-spin Lagrangians

International Nuclear Information System (INIS)

Francia, Dario; Lyakhovich, Simon L.; Sharapov, Alexey A.

2014-01-01

In their simplest form, metric-like Lagrangians for higher-spin massless fields are usually assumed to display constrained gauge symmetries, unless auxiliary fields are introduced or locality is foregone. Specifically, in its standard incarnation, gauge invariance of Maxwell-like Lagrangians relies on parameters with vanishing divergence. We find an alternative form of the corresponding local symmetry involving unconstrained gauge parameters of mixed-symmetry type, described by rectangular two-row Young diagrams and entering high-derivative gauge transformations. The resulting gauge algebra appears to be reducible and we display the full pattern of gauge-for-gauge parameters, testing its correctness via the corresponding counting of degrees of freedom. The algebraic techniques applied in this work also allow us to elucidate some general properties of linear gauge systems. In particular, we establish the general fact that any linear local field theory always admits unconstrained, local, and finitely reducible parametrization of the gauge symmetry. Incidentally, this shows that massless higher spins admit a local unconstrained formulation with no need for auxiliary fields

Gauge/gravity duality applied to condensed matter systems

International Nuclear Information System (INIS)

Ammon, Martin Matthias

2010-01-01

DE024486693In the present thesis by means of the AdS/CFT correspondence phenomena of strongly coupled quantum critical systems are studied. Hereby the assumption developed 1997 by Maldacena puts four-dimensional N=4 supersymmetric Yang-Mills theory and type IIB supergravity in the five-dimensional anti-de Sitter space in relation. This assumption can be generalized in different ways. So on the gauge-theory side states with finite temperature and density can be considered or degrees of freedom added, which transform in the fundamental representation of the gauge group, the so-called flavor degrees of freedom. These deformations of the correspondence are applied in the present thesis in order to understand better strongly coupled systems in the neighbourhood of quantum-critical points. We approximate hereby the field theory at the quantum-critical point by N=4 supersymmetric Yang-Mills theory. The charge carriers of the system are introduced by supersymmetric flavor fields. For instance in the present thesis in the case of two flavor fields, which have the same mass, a chemical potential for the isospin is considered and the phase diagram studied. The isospin-chemical potential breaks hereby the non-Abelian part of the flavor symmetry SU(2) to U(1). If a critical value of the isospin-chemical potential is exceeded, so shows our calculation, that the strongly coupled system becomes unstable against fluctuations. A new thermodynamically favorized state is formed. This state breaks the residual U(1) flavor symmetry spontaneously and can therefore be considered as a superfluid. If U(1) is gauged, by this way a superconductor is obtained. The AC conductivity goes in the superconducting phase for small frequencies to zero. The DC conductivity however is infinite. Furthermore we calculate the Fermi surface in the superconducting phase. Furthermore a holographic method for the calculation of the DC conductivity in arbitrarily constant electric and magnetic fields is further

Gauge/gravity duality applied to condensed matter systems

Energy Technology Data Exchange (ETDEWEB)

Ammon, Martin Matthias

2010-07-07

DE024486693In the present thesis by means of the AdS/CFT correspondence phenomena of strongly coupled quantum critical systems are studied. Hereby the assumption developed 1997 by Maldacena puts four-dimensional N=4 supersymmetric Yang-Mills theory and type IIB supergravity in the five-dimensional anti-de Sitter space in relation. This assumption can be generalized in different ways. So on the gauge-theory side states with finite temperature and density can be considered or degrees of freedom added, which transform in the fundamental representation of the gauge group, the so-called flavor degrees of freedom. These deformations of the correspondence are applied in the present thesis in order to understand better strongly coupled systems in the neighbourhood of quantum-critical points. We approximate hereby the field theory at the quantum-critical point by N=4 supersymmetric Yang-Mills theory. The charge carriers of the system are introduced by supersymmetric flavor fields. For instance in the present thesis in the case of two flavor fields, which have the same mass, a chemical potential for the isospin is considered and the phase diagram studied. The isospin-chemical potential breaks hereby the non-Abelian part of the flavor symmetry SU(2) to U(1). If a critical value of the isospin-chemical potential is exceeded, so shows our calculation, that the strongly coupled system becomes unstable against fluctuations. A new thermodynamically favorized state is formed. This state breaks the residual U(1) flavor symmetry spontaneously and can therefore be considered as a superfluid. If U(1) is gauged, by this way a superconductor is obtained. The AC conductivity goes in the superconducting phase for small frequencies to zero. The DC conductivity however is infinite. Furthermore we calculate the Fermi surface in the superconducting phase. Furthermore a holographic method for the calculation of the DC conductivity in arbitrarily constant electric and magnetic fields is further

Gauge bridges in classical field theory; Eichbruecken in der klassischen Feldtheorie

Energy Technology Data Exchange (ETDEWEB)

Jakobs, S.

2009-03-15

In this thesis Poisson structures of two classical gauge field theories (Maxwell-Klein-Gordon- and Maxwell-Dirac-system) are constructed using the parametrix construction of Green's functions. Parametrices for the Maxwell-Klein-Gordon- and Maxwell-Dirac-system are constructed in Minkowski space and this construction is later generalized to curved space times for the Maxwell-Klein-Gordon-system. With these Green's functions Poisson brackets will be defined as Peierls brackets. Finally non-local, gauge invariant observables, the so-called 'gauge bridges'are constructed. Gauge bridges are the matrix elements of holonomy operators. It is shown, that these emerge from Poisson brackets of local, gauge invariant observables. (orig.)

Nambu–Poisson gauge theory

Energy Technology Data Exchange (ETDEWEB)

Jurčo, Branislav, E-mail: jurco@karlin.mff.cuni.cz [Charles University in Prague, Faculty of Mathematics and Physics, Mathematical Institute, Prague 186 75 (Czech Republic); Schupp, Peter, E-mail: p.schupp@jacobs-university.de [Jacobs University Bremen, 28759 Bremen (Germany); Vysoký, Jan, E-mail: vysokjan@fjfi.cvut.cz [Jacobs University Bremen, 28759 Bremen (Germany); Czech Technical University in Prague, Faculty of Nuclear Sciences and Physical Engineering, Prague 115 19 (Czech Republic)

2014-06-02

We generalize noncommutative gauge theory using Nambu–Poisson structures to obtain a new type of gauge theory with higher brackets and gauge fields. The approach is based on covariant coordinates and higher versions of the Seiberg–Witten map. We construct a covariant Nambu–Poisson gauge theory action, give its first order expansion in the Nambu–Poisson tensor and relate it to a Nambu–Poisson matrix model.

Nambu–Poisson gauge theory

International Nuclear Information System (INIS)

Jurčo, Branislav; Schupp, Peter; Vysoký, Jan

2014-01-01

We generalize noncommutative gauge theory using Nambu–Poisson structures to obtain a new type of gauge theory with higher brackets and gauge fields. The approach is based on covariant coordinates and higher versions of the Seiberg–Witten map. We construct a covariant Nambu–Poisson gauge theory action, give its first order expansion in the Nambu–Poisson tensor and relate it to a Nambu–Poisson matrix model.

Local gauge coupling running in supersymmetric gauge theories on orbifolds

International Nuclear Information System (INIS)

Hillenbach, M.

2007-01-01

By extending Feynman's path integral calculus to fields which respect orbifold boundary conditions we provide a straightforward and convenient framework for loop calculations on orbifolds. We take advantage of this general method to investigate supersymmetric Abelian and non-Abelian gauge theories in five, six and ten dimensions where the extra dimensions are compactified on an orbifold. We consider hyper and gauge multiplets in the bulk and calculate the renormalization of the gauge kinetic term which in particular allows us to determine the gauge coupling running. The renormalization of the higher dimensional theories in orbifold spacetimes exhibits a rich structure with three principal effects: Besides the ordinary renormalization of the bulk gauge kinetic term the loop effects may require the introduction of both localized gauge kinetic terms at the fixed points/planes of the orbifold and higher dimensional operators. (orig.)

Local gauge coupling running in supersymmetric gauge theories on orbifolds

Energy Technology Data Exchange (ETDEWEB)

Hillenbach, M.

2007-11-21

By extending Feynman's path integral calculus to fields which respect orbifold boundary conditions we provide a straightforward and convenient framework for loop calculations on orbifolds. We take advantage of this general method to investigate supersymmetric Abelian and non-Abelian gauge theories in five, six and ten dimensions where the extra dimensions are compactified on an orbifold. We consider hyper and gauge multiplets in the bulk and calculate the renormalization of the gauge kinetic term which in particular allows us to determine the gauge coupling running. The renormalization of the higher dimensional theories in orbifold spacetimes exhibits a rich structure with three principal effects: Besides the ordinary renormalization of the bulk gauge kinetic term the loop effects may require the introduction of both localized gauge kinetic terms at the fixed points/planes of the orbifold and higher dimensional operators. (orig.)

Notes on gauge theory and gravitation

International Nuclear Information System (INIS)

Wallner, R.P.

1981-01-01

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) = (R 4 , +), 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 (U 4 -spacetime) comes into play. (Auth.)

Gauge fields

International Nuclear Information System (INIS)

Mills, R.

1989-01-01

This article is a survey of the history and ideas of gauge theory. Described here are the gradual emergence of symmetry as a driving force in the shaping of physical theory; the elevation of Noether's theorem, relating symmetries to conservation laws, to a fundamental principle of nature; and the force of the idea (''the gauge principle'') that the symmetries of nature, like the interactions themselves, should be local in character. The fundamental role of gauge fields in mediating the interactions of physics springs from Noether's theorem and the gauge principle in a remarkably clean and elegant way, leaving, however, some tantalizing loose ends that might prove to be the clue to a future deeper level of understanding. The example of the electromagnetic field as the prototype gauge theory is discussed in some detail and serves as the basis for examining the similarities and differences that emerge in generalizing to non-Abelian gauge theories. The article concludes with a brief examination of the dream of total unification: all the forces of nature in a single unified gauge theory, with the differences among the forces due to the specific way in which the fundamental symmetries are broken in the local environment

Nonlocal gauge theories

International Nuclear Information System (INIS)

Partovi, M.H.

1982-01-01

From a generalization of the covariant derivative, nonlocal gauge theories are developed. These theories enjoy local gauge invariance and associated Ward identities, a corresponding locally conserved current, and a locally conserved energy-momentum tensor, with the Ward identities implying the masslessness of the gauge field as in local theories. Their ultraviolet behavior allows the presence as well as the absence of the Adler-Bell-Jackiw anomaly, the latter in analogy with lattice theories

Is scale-invariance in gauge-Yukawa systems compatible with the graviton?

Science.gov (United States)

Christiansen, Nicolai; Eichhorn, Astrid; Held, Aaron

2017-10-01

We explore whether perturbative interacting fixed points in matter systems can persist under the impact of quantum gravity. We first focus on semisimple gauge theories and show that the leading order gravity contribution evaluated within the functional Renormalization Group framework preserves the perturbative fixed-point structure in these models discovered in [J. K. Esbensen, T. A. Ryttov, and F. Sannino, Phys. Rev. D 93, 045009 (2016)., 10.1103/PhysRevD.93.045009]. We highlight that the quantum-gravity contribution alters the scaling dimension of the gauge coupling, such that the system exhibits an effective dimensional reduction. We secondly explore the effect of metric fluctuations on asymptotically safe gauge-Yukawa systems which feature an asymptotically safe fixed point [D. F. Litim and F. Sannino, J. High Energy Phys. 12 (2014) 178., 10.1007/JHEP12(2014)178]. The same effective dimensional reduction that takes effect in pure gauge theories also impacts gauge-Yukawa systems. There, it appears to lead to a split of the degenerate free fixed point into an interacting infrared attractive fixed point and a partially ultraviolet attractive free fixed point. The quantum-gravity induced infrared fixed point moves towards the asymptotically safe fixed point of the matter system, and annihilates it at a critical value of the gravity coupling. Even after that fixed-point annihilation, graviton effects leave behind new partially interacting fixed points for the matter sector.

General gauge mediation at the weak scale

Energy Technology Data Exchange (ETDEWEB)

Knapen, Simon [Berkeley Center for Theoretical Physics,University of California, Berkeley, CA 94720 (United States); Theoretical Physics Group, Lawrence Berkeley National Laboratory,Berkeley, CA 94720 (United States); Redigolo, Diego [Sorbonne Universités, UPMC Univ Paris 06,UMR 7589, LPTHE, F-75005, Paris (France); CNRS, UMR 7589,LPTHE, F-75005, Paris (France); Shih, David [New High Energy Theory Center, Rutgers University,Piscataway, NJ 08854 (United States)

2016-03-09

We completely characterize General Gauge Mediation (GGM) at the weak scale by solving all IR constraints over the full parameter space. This is made possible through a combination of numerical and analytical methods, based on a set of algebraic relations among the IR soft masses derived from the GGM boundary conditions in the UV. We show how tensions between just a few constraints determine the boundaries of the parameter space: electroweak symmetry breaking (EWSB), the Higgs mass, slepton tachyons, and left-handed stop/sbottom tachyons. While these constraints allow the left-handed squarks to be arbitrarily light, they place strong lower bounds on all of the right-handed squarks. Meanwhile, light EW superpartners are generic throughout much of the parameter space. This is especially the case at lower messenger scales, where a positive threshold correction to m{sub h} coming from light Higgsinos and winos is essential in order to satisfy the Higgs mass constraint.

Yang-Mills-Vlasov system in the temporal gauge

International Nuclear Information System (INIS)

Choquet-Bruhat, Y.; Noutchegueme, N.

1991-01-01

We prove a local in time existence theorem of a solution of the Cauchy problem for the Yang-Mills-Vlasov integrodifferential system. Such equations govern the evolution of plasmas, for instance of quarks and gluons (quagmas), where non abelian gauge fields and Yang-Mills charges replace the usual electromagnetic field and electric charge. We work with the temporal gauge and use functional spaces with appropriate weight on the momenta, but no fall off is required in the space direction [fr

Development of measurement system for gauge block interferometer

Science.gov (United States)

Chomkokard, S.; Jinuntuya, N.; Wongkokua, W.

2017-09-01

We developed a measurement system for collecting and analyzing the fringe pattern images from a gauge block interferometer. The system was based on Raspberry Pi which is an open source system with python programming and opencv image manipulation library. The images were recorded by the Raspberry Pi camera with five-megapixel capacity. The noise of images was suppressed for the best result in analyses. The low noise images were processed to find the edge of fringe patterns using the contour technique for the phase shift analyses. We tested our system with the phase shift patterns between a gauge block and a reference plate. The phase shift patterns were measured by a Twyman-Green type of interferometer using the He-Ne laser with the temperature controlled at 20.0 °C. The results of the measurement will be presented and discussed.

BRST cosmology and BRST gauge fixing

International Nuclear Information System (INIS)

Kalau, W.; Nationaal Inst. voor Kernfysica en Hoge-Energiefysica; Holten, J.W. van

1991-01-01

Some general aspects of BRST cohomology are discussed. The BRST gauge-fixing procedure based on the harmonic gauges in the ghost-extended quantum mechanical Hilbert space. A general classification of states according to their BRST transformation properties is obtained.On the basis of these results necessary and sufficient conditions are found for the positivity of the physical state space following an earlier analysis of Spiegelglas. The method is applied to a system with a non semi-simple, solvable algebra of first-class constraints, such as appears in the theory of massless higher spins. It is found that both the Dirac and Gupta-Bleuler quantization procedures are contained within the BRST approach. (author). 15 refs

Direct gauging of the Poincare group V. Group scaling, classical gauge theory, and gravitational corrections

International Nuclear Information System (INIS)

Edelen, D.G.B.

1986-01-01

Homogeneous scaling of the group space of the Poincare group, P 10 , is shown to induce scalings of all geometric quantities associated with the local action of P 10 . The field equations for both the translation and the Lorentz rotation compensating fields reduce to O(1) equations if the scaling parameter is set equal to the general relativistic gravitational coupling constant 8πGc -4 . Standard expansions of all field variables in power series in the scaling parameter give the following results. The zeroth-order field equations are exactly the classical field equations for matter fields on Minkowski space subject to local action of an internal symmetry group (classical gauge theory). The expansion process is shown to break P 10 -gauge covariance of the theory, and hence solving the zeroth-order field equations imposes an implicit system of P 10 -gauge conditions. Explicit systems of field equations are obtained for the first- and higher-order approximations. The first-order translation field equations are driven by the momentum-energy tensor of the matter and internal compensating fields in the zeroth order (classical gauge theory), while the first-order Lorentz rotation field equations are driven by the spin currents of the same classical gauge theory. Field equations for the first-order gravitational corrections to the matter fields and the gauge fields for the internal symmetry group are obtained. Direct Poincare gauge theory is thus shown to satisfy the first two of the three-part acid test of any unified field theory. Satisfaction of the third part of the test, at least for finite neighborhoods, seems probable

Relativistic generalization and extension to the non-Abelian gauge theory of Feynman's proof of the Maxwell equations

International Nuclear Information System (INIS)

Tanimura, Shogo

1992-01-01

R. P. Feynman showed F. J. Dyson a proof of the Lorentz force law and the homogeneous Maxwell equations, which he obtained starting from Newton's law of motion and the commutation relations between position and velocity for a single nonrelativistic particle. The author formulate both a special relativistic and a general relativistic version of Feynman's derivation. Especially in the general relativistic version they prove that the only possible fields that can consistently act on a quantum mechanical particle are scalar, gauge, and gravitational fields. They also extend Feynman's scheme to the case of non-Abelian gauge theory in the special relativistic context. 8 refs

Duffin-Kemmer formulation of gauge theories

International Nuclear Information System (INIS)

Okubo, S.; Tosa, Y.

1979-01-01

Gauge theories, including the Yang-Mills theory as well as Einstein's general relativity, are reformulated in first-order differential forms. In this generalized Duffin-Kemmer formalism, gauge theories take very simple forms with only cubic interactions. Moreover, every local gauge transformation, e.g., that of Yang and Mills or Einstein, etc., has an essentially similar form. Other examples comprise a gauge theory akin to the Sugawara theory of currents and the nonlinear realization of chiral symmetry. The octonion algebra is found possibly relevant to the discussion of the Yang-Mills theory

Higher spin gauge theories in any dimension

International Nuclear Information System (INIS)

Vasiliev, M.A.

2004-01-01

Some general properties of higher spin (HS) gauge theories are summarized, with the emphasize on the nonlinear theories in any dimension. The main conclusion is that nonlinear HS theories exist in any dimension. Note that HS gauge symmetries in the nonlinear HS theory differ from the Yang-Mills gauging of the global HS symmetry of a free theory one starts with by HS field strength dependent nonlinear corrections resulting from the partial gauge fixing of spontaneously broken HS symmetries in the extended non-commutative space. The HS geometry is that of the fuzzy hyperboloid in the auxiliary (fiber) non-commutative space. Its radius depends on the Weyl 0-forms which take values in the infinitive-dimensional module dual to the space of single-particle states in the system

On the N=1{sup ∗} gauge theory on a circle and elliptic integrable systems

Energy Technology Data Exchange (ETDEWEB)

Bourget, Antoine; Troost, Jan [Laboratoire de Physique Théorique, Ecole Normale Supérieure,24 rue Lhomond, 75005 Paris (France)

2016-01-18

We continue our study of the N=1{sup ∗} supersymmetric gauge theory on ℝ{sup 2,1}×S{sup 1} and its relation to elliptic integrable systems. Upon compactification on a circle, we show that the semi-classical analysis of the massless and massive vacua depends on the classification of nilpotent orbits, as well as on the conjugacy classes of the component group of their centralizer. We demonstrate that semi-classically massless vacua can be lifted by Wilson lines in unbroken discrete gauge groups. The pseudo-Levi subalgebras that play a classifying role in the nilpotent orbit theory are also key in defining generalized Inozemtsev limits of (twisted) elliptic integrable systems. We illustrate our analysis in the N=1{sup ∗} theories with gauge algebras su(3), su(4), so(5) and for the exceptional gauge algebra G{sub 2}. We map out modular duality diagrams of the massive and massless vacua. Moreover, we provide an analytic description of the branches of massless vacua in the case of the su(3) and the so(5) theory. The description of these branches in terms of the complexified Wilson lines on the circle invokes the Eichler-Zagier technique for inverting the elliptic Weierstrass function. After fine-tuning the coupling to elliptic points of order three, we identify the Argyres-Douglas singularities of the su(3)N=1{sup ∗} theory.

Self-dual configurations in Abelian Higgs models with k-generalized gauge field dynamics

Energy Technology Data Exchange (ETDEWEB)

Casana, R.; Cavalcante, A. [Departamento de Física, Universidade Federal do Maranhão,65080-805, São Luís, Maranhão (Brazil); Hora, E. da [Departamento de Física, Universidade Federal do Maranhão,65080-805, São Luís, Maranhão (Brazil); Coordenadoria Interdisciplinar de Ciência e Tecnologia, Universidade Federal do Maranhão,65080-805, São Luís, Maranhão (Brazil)

2016-12-14

We have shown the existence of self-dual solutions in new Maxwell-Higgs scenarios where the gauge field possesses a k-generalized dynamic, i.e., the kinetic term of gauge field is a highly nonlinear function of F{sub μν}F{sup μν}. We have implemented our proposal by means of a k-generalized model displaying the spontaneous symmetry breaking phenomenon. We implement consistently the Bogomol’nyi-Prasad-Sommerfield formalism providing highly nonlinear self-dual equations whose solutions are electrically neutral possessing total energy proportional to the magnetic flux. Among the infinite set of possible configurations, we have found families of k-generalized models whose self-dual equations have a form mathematically similar to the ones arising in the Maxwell-Higgs or Chern-Simons-Higgs models. Furthermore, we have verified that our proposal also supports infinite twinlike models with |ϕ|{sup 4}-potential or |ϕ|{sup 6}-potential. With the aim to show explicitly that the BPS equations are able to provide well-behaved configurations, we have considered a test model in order to study axially symmetric vortices. By depending of the self-dual potential, we have shown that the k-generalized model is able to produce solutions that for long distances have a exponential decay (as Abrikosov-Nielsen-Olesen vortices) or have a power-law decay (characterizing delocalized vortices). In all cases, we observe that the generalization modifies the vortex core size, the magnetic field amplitude and the bosonic masses but the total energy remains proportional to the quantized magnetic flux.

Gauge theory description of compactified pp-waves

International Nuclear Information System (INIS)

Bertolini, Matteo; Boer, Jan de; Harmark, Troels; Imeroni, Emiliano; Obers, Niels A.

2003-01-01

We find a new Penrose limit of AdS 5 xS 5 that gives the maximally symmetric pp-wave background of type-IIB string theory in a coordinate system that has a manifest space-like isometry. This induces a new pp-wave/gauge-theory duality which on the gauge theory side involves a novel scaling limit of N=4 SYM theory. The new Penrose limit, when applied to AdS 5 xS 5 /Z M , yields a pp-wave with a space-like circle. The dual gauge theory description involves a triple scaling limit of an N=2 quiver gauge theory. We present in detail the map between gauge theory operators and string theory states including winding states, and verify agreement between the energy eigenvalues obtained from string theory and those computed in gauge theory, at least to one-loop order in the planar limit. We furthermore consider other related new Penrose limits and explain how these limits can be understood as part of a more general framework. (author)

Some observations on interpolating gauges and non-covariant gauges

International Nuclear Information System (INIS)

Joglekar, Satish D.

2003-01-01

We discuss the viability of using interpolating gauges to define the non-covariant gauges starting from the covariant ones. We draw attention to the need for a very careful treatment of boundary condition defining term. We show that the boundary condition needed to maintain gauge invariance as the interpolating parameter θ varies, depends very sensitively on the parameter variation. We do this with a gauge used by Doust. We also consider the Lagrangian path-integrals in Minkowski space for gauges with a residual gauge-invariance. We point out the necessity of inclusion of an ε-term (even) in the formal treatments, without which one may reach incorrect conclusions. We, further, point out that the ε-term can contribute to the BRST WT-identities in a non-trivial way (even as ε → 0). We point out that these contributions lead to additional constraints on Green's function that are not normally taken into account in the BRST formalism that ignores the ε-term, and that they are characteristic of the way the singularities in propagators are handled. We argue that a prescription, in general, will require renormalization; if at all it is to be viable. (author)

Poincare gauge in electrodynamics

International Nuclear Information System (INIS)

Brittin, W.E.; Smythe, W.R.; Wyss, W.

1982-01-01

The gauge presented here, which we call the Poincare gauge, is a generalization of the well-known expressions phi = -rxE 0 and A = 1/2 B 0 x r for the scalar and vector potentials which describe static, uniform electric and magnetic fields. This gauge provides a direct method for calculating a vector potential for any given static or dynamic magnetic field. After we establish the validity and generality of this gauge, we use it to produce a simple and unambiguous method of computing the flux linking an arbitrary knotted and twisted closed circuit. The magnetic flux linking the curve bounding a Moebius band is computed as a simple example. Arguments are then presented that physics students should have the opportunity of learning early in their curriculum modern geometric approaches to physics. (The language of exterior calculus may be as important to future physics as vector calculus was to the past.) Finally, an appendix illustrates how the Poincare gauge (and others) may be derived from Poincare's lemma relating exact and closed exterior differential forms

Unibert - PC software for radiometric level gauging - the LB440 measuring system

International Nuclear Information System (INIS)

Mann, H.; Bickert, M.

2001-01-01

In almost all industrial branches radiometric measuring systems are being used today for a lot of different tasks. The most common field of this application are level gauging measurements by use of gamma radiation, i.e. for level detection as well as for level gauging over ranges of up to several meters. For our level gauge measuring system LB440 we developed a clearly arranged PC software, which allows starting, measuring and service of the level gauge. Over the RS232-interface the industrial computer can be connected with a Laptop or PC. The software is a supplemental or even a substitute for the operation over the frontpanel. The measuring system can be completely controlled by the Unibert PC-Software, realised by LabVIEW 5.1.1, which offers an interactive graphical user interface. The same functionality as in the ''embedded - software'' is available, completed with some additional functions. (orig.) [de

Universal dynamics of complex adaptive systems: Gauge theory of things alive

International Nuclear Information System (INIS)

Mack, G.

1994-04-01

A universal dynamics of objects and their relations - a kind of ''universal chemistry'' - is discussed which satisfies general principles of locality and relativity. Einsteins theory of gravitation and the gauge theory of elementary particles are prototypes, but complex adaptive systems - anything that is alive in the widest sense - fall under the same paradigma. Frustration and gauge symmetry arise naturally in this context. Besides a nondissipative deterministic dynamics, which is thought to operate at a fundamental levle, a Thermo-Dynamics in sense of Prigogine is introduced by adding a diffusion process. It introduces irreversibility and entropy production. It equilibrates the chaotic local model of the time development (only) and is designed to be undetectable under continued observation with given finite measuring accuracy. Compositeness and the development of structure can be described in this framework. The existence of a critical equilibrium state may be postulated which is invariant under the dynamics. But it is usually not reached in a finite time from a given starting configuration, because local dynamics suffers from critical slowing down, especially in the presence of frustration. (orig.)

On the relativity and equivalence principles in the gauge theory of gravitation

International Nuclear Information System (INIS)

Ivanenko, D.; Sardanashvily, G.

1981-01-01

One sees the basic ideas of the gauge gravitation theory still not generally accepted in spite of more than twenty years of its history. The chief reason lies in the fact that the gauge character of gravity is connected with the whole complex of problems of Einstein General Relativity: about the reference system definition, on the (3+1)-splitting, on the presence (or absence) of symmetries in GR, on the necessity (or triviality) of general covariance, on the meaning of equivalence principle, which led Einstein from Special to General Relativity |1|. The real actuality of this complex of interconnected problems is demonstrated by the well-known work of V. Fock, who saw no symmetries in General Relativity, declared the unnecessary Equivalence principle and proposed even to substitute the designation ''chronogeometry'' instead of ''general relativity'' (see also P. Havas). Developing this line, H. Bondi quite recently also expressed doubts about the ''relativity'' in Einstein theory of gravitation. All proposed versions of the gauge gravitation theory must clarify the discrepancy between Einstein gravitational field being a pseudo-Riemannian metric field, and the gauge potentials representing connections on some fiber bundles and there exists no group, whose gauging would lead to the purely gravitational part of connection (Christoffel symbols or Fock-Ivenenko-Weyl spinorial coefficients). (author)

UIO-based Fault Diagnosis for Hydraulic Automatic Gauge Control System of Magnesium Sheet Mill

Directory of Open Access Journals (Sweden)

Li-Ping FAN

2014-02-01

Full Text Available Hydraulic automatic gauge control system of magnesium sheet mill is a complex integrated control system, which including mechanical, hydraulic and electrical comprehensive information. The failure rate of AGC system always is high, and its fault reasons are always complex. Based on analyzing the fault of main components of the automatic gauge control system, unknown input observer is used to realize fault diagnosis and isolation. Simulation results show that the fault diagnosis method based on the unknown input observer for the hydraulic automatic gauge control system of magnesium sheet mill is effective.

Gauging Quantum States: From Global to Local Symmetries in Many-Body Systems

Directory of Open Access Journals (Sweden)

Jutho Haegeman

2015-02-01

Full Text Available We present an operational procedure to transform global symmetries into local symmetries at the level of individual quantum states, as opposed to typical gauging prescriptions for Hamiltonians or Lagrangians. We then construct a compatible gauging map for operators, which preserves locality and reproduces the minimal coupling scheme for simple operators. By combining this construction with the formalism of projected entangled-pair states (PEPS, we can show that an injective PEPS for the matter fields is gauged into a G-injective PEPS for the combined gauge-matter system, which potentially has topological order. We derive the corresponding parent Hamiltonian, which is a frustration-free gauge-theory Hamiltonian 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. This scheme results in a low-parameter family of gauge-invariant states of which we can accurately probe the phase diagram, as we illustrate by studying a Z_{2} gauge theory with Higgs matter.

Gauge coupling unification in six dimensions

Energy Technology Data Exchange (ETDEWEB)

Lee, H.M. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)]|[Carnegie-Mellon Univ., Pittsburgh, PA (United States). Dept. of Physics

2006-11-15

We compute the one-loop gauge couplings in six-dimensional non-Abelian gauge theories on the T{sup 2}/Z{sub 2} orbifold with general GUT breaking boundary conditions. For concreteness, we apply the obtained general formulae to the gauge coupling running in a 6D SO(10) orbifold GUT where the GUT group is broken down to the standard model gauge group up to an extra U(1). We find that the one-loop corrections depend on the parity matrices encoding the orbifold boundary conditions as well as the volume and shape moduli of extra dimensions. When the U(1) is broken by the VEV of bulk singlets, the accompanying extra color triplets also affect the unification of the gauge couplings. In this case, the B-L breaking scale is closely linked to the compactification scales for maintaining a success of the gauge coupling unification. (orig.)

Renormalization of gauge theories in the background-field approach arXiv

CERN Document Server

Barvinsky, Andrei O.; Herrero-Valea, Mario; Sibiryakov, Sergey M.; Steinwachs, Christian F.

Using the background-field method we demonstrate the Becchi-Rouet-Stora-Tyutin (BRST) structure of counterterms in a broad class of gauge theories. Put simply, we show that gauge invariance is preserved by renormalization in local gauge field theories whenever they admit a sensible background-field formulation and anomaly-free path integral measure. This class encompasses Yang-Mills theories (with possibly Abelian subgroups) and relativistic gravity, including both renormalizable and non-renormalizable (effective) theories. Our results also hold for non-relativistic models such as Yang-Mills theories with anisotropic scaling or Horava gravity. They strengthen and generalize the existing results in the literature concerning the renormalization of gauge systems. Locality of the BRST construction is emphasized throughout the derivation. We illustrate our general approach with several explicit examples.

Gauge field condensation in geometric quantum chromodynamics

International Nuclear Information System (INIS)

Guendelman, E.I.

1991-09-01

In odd number of dimensions, it is possible to construct general covariant gauge theories, where the metric is not an independent variable, but local function of the gauge fields. Starting from standardly defined gauge theory, upon functional integration of some variables, we could end up with such moodels. For models with SU(2) and SU(3) symmetry in three dimensions, gauge field condensation take place in the vacuum, which is nevertheless homogeneous and isotropic up to a gauge transformation, provided the space is flat. Introducing Higgs fields that spontaneously break the gauge symmetry, we get a breakdown of the homogenity and isotropy of the vacuum. Finally, we discuss how some of this ideas can be generalized to four and other even dimensions. (author)

PyR@TE. Renormalization group equations for general gauge theories

Science.gov (United States)

Lyonnet, F.; Schienbein, I.; Staub, F.; Wingerter, A.

2014-03-01

Although the two-loop renormalization group equations for a general gauge field theory have been known for quite some time, deriving them for specific models has often been difficult in practice. This is mainly due to the fact that, albeit straightforward, the involved calculations are quite long, tedious and prone to error. The present work is an attempt to facilitate the practical use of the renormalization group equations in model building. To that end, we have developed two completely independent sets of programs written in Python and Mathematica, respectively. The Mathematica scripts will be part of an upcoming release of SARAH 4. The present article describes the collection of Python routines that we dubbed PyR@TE which is an acronym for “Python Renormalization group equations At Two-loop for Everyone”. In PyR@TE, once the user specifies the gauge group and the particle content of the model, the routines automatically generate the full two-loop renormalization group equations for all (dimensionless and dimensionful) parameters. The results can optionally be exported to LaTeX and Mathematica, or stored in a Python data structure for further processing by other programs. For ease of use, we have implemented an interactive mode for PyR@TE in form of an IPython Notebook. As a first application, we have generated with PyR@TE the renormalization group equations for several non-supersymmetric extensions of the Standard Model and found some discrepancies with the existing literature. Catalogue identifier: AERV_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AERV_v1_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 924959 No. of bytes in distributed program, including test data, etc.: 495197 Distribution format: tar.gz Programming language: Python. Computer

Electronic supply system ''BING'' for vibrating wire strain gauges

International Nuclear Information System (INIS)

Himmler, H.

1976-02-01

In the Austrian project Prestressed Concrete Pressure Vessel-High Temperature Helium Test Rig a great number of strain gauges is to be monitored continuously. For these measurements an electronic supply equipment had to be developed and built. The problem was solved by the ''BING'' system, which transmits an electromagnetic impulse to the string of the strain gauge thus enabling a measurement of frequency and temperature. The equipment has been in use for 1 1/2 years without major troubles. (author)

Class of very simple gauge theories which remain renormalizable even in the limit of infinite gauge coupling constant

International Nuclear Information System (INIS)

Kaptanoglu, S.

1983-01-01

A class of local gauge theories based on compact semisimple Lie groups is studied in the limit of infinite gauge coupling constant (g = infinity). In general, in this limit, the gauge fields become auxiliary in all gauge theories, and the system develops a richer structure of constraints. Unfortunately for most gauge theories, this limit turns out to be too singular to quantize and the theory ceases to be renormalizable. For a special class of gauge theories, however, where there are no fermions and there is only one multiplet of scalars in the adjoint representation, we prove that a consistent renormalizable quantum theory exists even in this very singular limit. We trace this exceptional behavior to a new local translationlike symmetry in the functional space that this class of gauge models possesses in the limit of infinite gauge coupling constant. By carrying out the constraint analysis, evaluating the Faddeev-Popov-Senjanovic determinant, and doing the functional integrations over the canonical momenta, the gauge fields, and most of the components of the scalar fields, we obtain an extremely simple result with no non-Abelian structure left in it. For example, for the group SU(2), the final answer reduces to the theory of a one-component self-interacting real phi 4 scalar field theory. Throughout this paper, we use functional methods and make no approximations; our results are nonperturbative and exact. We also discuss some of the possible implications of our results

Relativity and equivalence principles in the gauge theory of gravitation

International Nuclear Information System (INIS)

Ivanenko, D.; Sardanashvili, G.

1981-01-01

Roles of relativity (RP) and equivalence principles (EP) in the gauge theory of gravity are shown. RP in the gravitational theory in formalism of laminations can be formulated as requirement of covariance of equations relative to the GL + (4, R)(X) gauge group. In such case RP turns out to be identical to the gauge principle in the gauge theory of a group of outer symmetries, and the gravitational theory can be directly constructed as the gauge theory. In general relativity theory the equivalence theory adds RP and is intended for description of transition to a special relativity theory in some system of reference. The approach described takes into account that in the gauge theory, besides gauge fields under conditions of spontaneous symmetry breaking, the Goldstone and Higgs fields can also arise, to which the gravitational metric field is related, what is the sequence of taking account of RP in the gauge theory of gravitation [ru

Non-Abelian gauge fields in two spatial dimensions

International Nuclear Information System (INIS)

Hagen, C.R.

1987-01-01

Generalizing an earlier work on the Abelian case the most general non-Abelian gauge theory in two spatial dimensions is derived. It is shown that local gauge invariance leads to a new term in the action which in turn requires that the gauge current operator have a part which is bilinear in the non-Abelian gauge field-strength tensor. Although a radiation (or axial) gauge quantization is possible, this approach is found not to yield the maximal set of commutation relations among the basic fields. The latter goal can be accomplished only by a rather unusual gauge choice which has not previously been studied. Quantization conditions on the coupling constant implied by invariance under large gauge transformations are also derived

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

International Nuclear Information System (INIS)

Lima, Gabriel Di Lemos Santiago

2014-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

Lima, Gabriel Di Lemos Santiago, E-mail: gabriellemos3@hotmail.com

2014-02-15

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.

What's wrong with anomalous chiral gauge theory?

International Nuclear Information System (INIS)

Kieu, T.D.

1994-05-01

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

Gauge and general covariance of string interactions

International Nuclear Information System (INIS)

Das, S.R.

1986-01-01

All fundamental interactions at observable energies seem to arise out of local symmetries - gauge invariances and general coordinate invariance. In usual field theories of point particles these invariances are postulated a priori: the idea is to deduce everything else from the symmetry group and the representation content of the matter fields. In string theories, the situation is rather different. Here the basic principle is reparametrization invariance on the world sheet swept out by the string. The authors consider the simplest string models-those defined on flat Minkowski space-time. The transverse oscillations of the string lead to an infinite tower of modes which may be thought of as the ''particles'' constituting the string. The interacting string theory is defined, in the first quantized formulation, by specifying the interaction of these modes with the string. These interaction vertices must satisfy a basic requirement: when any dual amplitude is factorized only physical states (i.e. those satisfying the Virasoro conditions) must occur as on-mass-shell intermediate states. This means that the vertices respect the reparametrization invariance of the world sheet, since it is this symmetry which eliminates ghost states by virtue of Virasoro conditions

A General Iterative Method for a Nonexpansive Semigroup in Banach Spaces with Gauge Functions

Directory of Open Access Journals (Sweden)

Kamonrat Nammanee

2012-01-01

Full Text Available We study strong convergence of the sequence generated by implicit and explicit general iterative methods for a one-parameter nonexpansive semigroup in a reflexive Banach space which admits the duality mapping Jφ, where φ is a gauge function on [0,∞. Our results improve and extend those announced by G. Marino and H.-K. Xu (2006 and many authors.

Investigation of spontaneously broken gauge theories

International Nuclear Information System (INIS)

Nagy, T.

1978-01-01

Spontaneously broken gauge theories (SBGT) with effects treated perturbatively are investigated. The general structure of SBGT is exhibited and gauge invariant renormalization program for practical calculations is set up. The proof of renormalizability of Lee and Zinn-Justin are extended to the problems of SBGT. A general semisimple compact gauge group is used. Arbitrary fermion and scalar multiplets are considered. The structure of the Lagrangian is discussed. The problem of quantization is described and the definition of the generating functionals of the Green functions and the Green functions themselves is given

Perturbative ambiguities in Coulomb gauge QCD

International Nuclear Information System (INIS)

Doust, P.

1987-01-01

The naive Coulomb gauge Feynman rules in non-abelian gauge theory give rise to ambiguous integrals, in addition to the usual ultraviolet divergences. Generalizing the work of Cheng and Tsai, these ambiguities are resolved to all orders in perturbation theory, by defining a gauge that interpolates smoothly between the Feynman gauge and the Coulomb gauge. The extra terms V 1 +V 2 of Christ and Lee are identified with certain two-loop ambiguous terms. However, there still seem to be unsolved problems connected with renormalisation. copyright 1987 Academic Press, Inc

Quasineutral Limit of the Schrödinger-Poisson System in Coulomb Gauge

OpenAIRE

Lin, Chi-Kun; Wong, Yau-Shu; Wu, Kung-Chien

2012-01-01

The zero Debye length asymptotic of the Schrödinger-Poisson system in Coulomb gauge for ill-prepared initial data is studied. We prove that when the scaled Debye length λ → 0, the current density defined by the solution of the Schrödinger-Poisson system in the Coulomb gauge converges to the solution of the rotating incompressible Euler equation plus a fast singular oscillating gradient vector field.

Stationary solutions of multicomponent chiral and gauge models

International Nuclear Information System (INIS)

Chudnovsky, D.V.; Chudnovsky, G.V.

1979-01-01

The authors examine stationary solutions of completely integrable systems in (x, t) dimensions having infinitely many components. Among the cases under investigation are: (1) the infinite-component non-linear Schroedinger equation; (2) infinite component CPsup(Ω) or SU(N) sigma-models; (3) general gauge and chiral completely integrable systems. (Auth.)

Two-parameter nonlinear spacetime perturbations: gauge transformations and gauge invariance

International Nuclear Information System (INIS)

Bruni, Marco; Gualtieri, Leonardo; Sopuerta, Carlos F

2003-01-01

An implicit fundamental assumption in relativistic perturbation theory is that there exists a parametric family of spacetimes that can be Taylor expanded around a background. The choice of the latter is crucial to obtain a manageable theory, so that it is sometime convenient to construct a perturbative formalism based on two (or more) parameters. The study of perturbations of rotating stars is a good example: in this case one can treat the stationary axisymmetric star using a slow rotation approximation (expansion in the angular velocity Ω), so that the background is spherical. Generic perturbations of the rotating star (say parametrized by λ) are then built on top of the axisymmetric perturbations in Ω. Clearly, any interesting physics requires nonlinear perturbations, as at least terms λΩ need to be considered. In this paper, we analyse the gauge dependence of nonlinear perturbations depending on two parameters, derive explicit higher-order gauge transformation rules and define gauge invariance. The formalism is completely general and can be used in different applications of general relativity or any other spacetime theory

Electromagnetic velocity gauge: use of multiple gauges, time response, and flow perturbations

International Nuclear Information System (INIS)

Erickson, L.M.; Johnson, C.B.; Parker, N.L.; Vantine, H.C.; Weingart, R.C.; Lee, R.S.

1981-01-01

We have developed an in-situ electromagnetic velocity (EMV) gauge system for use in multiple-gauge studies of initiating and detonating explosives. We have also investigated the risetime of the gauge and the manner in which it perturbs a reactive flow. We report on the special precautions that are necessary in multiple gauge experiments to reduce lead spreading, simplify target fabrication problems and minimize cross talk through the conducting explosive. Agreement between measured stress records and calculations from multiple velocity gauge data give us confidence that our velocity gauges are recording properly. We have used laser velocity interferometry to measure the gauge risetime in polymethyl methacrylate (PMMA). To resolve the difference in the two methods, we have examined hydrodynamic and material rate effects. In addition, we considered the effects of shock tilt, electronic response and magntic diffusion on the gauge's response time

Gauge threshold corrections for local orientifolds

International Nuclear Information System (INIS)

Conlon, Joseph P.; Palti, Eran

2009-01-01

We study gauge threshold corrections for systems of fractional branes at local orientifold singularities and compare with the general Kaplunovsky-Louis expression for locally supersymmetric N = 1 gauge theories. We focus on branes at orientifolds of the C 3 /Z 4 , C 3 /Z 6 and C 3 /Z 6 ' singularities. We provide a CFT construction of these theories and compute the threshold corrections. Gauge coupling running undergoes two phases: one phase running from the bulk winding scale to the string scale, and a second phase running from the string scale to the infrared. The first phase is associated to the contribution of N = 2 sectors to the IR β functions and the second phase to the contribution of both N = 1 and N = 2 sectors. In contrast, naive application of the Kaplunovsky-Louis formula gives single running from the bulk winding mode scale. The discrepancy is resolved through 1-loop non-universality of the holomorphic gauge couplings at the singularity, induced by a 1-loop redefinition of the twisted blow-up moduli which couple differently to different gauge nodes. We also study the physics of anomalous and non-anomalous U(1)s and give a CFT description of how masses for non-anomalous U(1)s depend on the global properties of cycles.

Mechanical System Analysis of C-Frame for Steel Plate Thickness Gauge

International Nuclear Information System (INIS)

Sri Sudadiyo

2007-01-01

Nuclear base instrument is not only applied in the area of research such as medical and agriculture sciences, but also in the field of industry especially for thickness gauge. To the present at the steel industry, the gauge that is applied to cut plate thickness using infra-red ray method, it cannot result in accurately data. To solve that case, it is developed a thickness gauge of steel plate by using gamma ray method that it is named C-Frame. This thickness gauge is hoped that it could control in cutting the steel plate by on-line, accurate, and safe, therefore, it could socialize the advanced technology in the nuclear field to support the production process in domestic industries (national industries). The present study yields the calculations of mechanical system of that C-Frame including structure, detector support, source container of radioisotope, and transmission system, be also computed by running Professional Microsoft Fortran Version 5.10, NISA-II program, and AutoCAD program. From the obtained results could be known that the design meets the requirement, so that could be employed properly to measure the thickness of plate in the steel industries. (author)

Gauged U(1) clockwork theory

Science.gov (United States)

Lee, Hyun Min

2018-03-01

We consider the gauged U (1) clockwork theory with a product of multiple gauge groups and discuss the continuum limit of the theory to a massless gauged U (1) with linear dilaton background in five dimensions. The localization of the lightest state of gauge fields on a site in the theory space naturally leads to exponentially small effective couplings of external matter fields localized away from the site. We discuss the implications of our general discussion with some examples, such as mediators of dark matter interactions, flavor-changing B-meson decays as well as D-term SUSY breaking.

Continuum gauge theories

International Nuclear Information System (INIS)

Stora, R.

1976-09-01

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

Gauge invariance and degree of freedom count

International Nuclear Information System (INIS)

Henneaux, M.; Universite Libre de Bruxelles; Teitelboim, C.; Texas Univ., Austin; Zanelli, J.; Chile Univ., Santiago. Dept. de Fisica)

1990-01-01

The precise relation between the gauge transformations in lagrangian and hamiltonian form is derived for any gauge theory. It is found that in order to define a lagrangian gauge symmetry, the coefficients of the first class constraints in the hamiltonian generator of gauge transformations must obey a set of differential equations. Those equations involve, in general, the Lagrange multipliers. Their solution contains as many arbitrary functions of time as there are primary first class constraints. If n is the number of generations of constraints (primary, secondary, tertiary...), the arbitrary functions appear in the general solution together with their successive time derivatives up to order n-1. The analysis yields as by-products: (i) a systematic way to derive all the gauge symmetries of a given lagrangian; (ii) a precise criterion for counting the physical degrees of freedom of a gauge theory directly from the form of gauge transformations in lagrangian form. This last part is illustrated by means of examples. The BRST analog of the counting of physical degrees of freedom is also discussed. (orig.)

Renormalization of supersymmetric gauge theories on orbifolds: Brane gauge couplings and higher derivative operators

International Nuclear Information System (INIS)

Groot Nibbelink, Stefan; Hillenbach, Mark

2005-01-01

We consider supersymmetric gauge theories coupled to hypermultiplets on five- and six-dimensional orbifolds and determine the bulk and local fixed point renormalizations of the gauge couplings. We infer from a component analysis that the hypermultiplet does not induce renormalization of the brane gauge couplings on the five-dimensional orbifold S 1 /Z 2 . This is not due to supersymmetry, since the bosonic and fermionic contributions cancel separately. We extend this investigation to T 2 /Z N orbifolds using supergraph techniques in six dimensions. On general Z N orbifolds the gauge couplings do renormalize at the fixed points, except for the Z 2 fixed points of even ordered orbifolds. To cancel the bulk one-loop divergences a dimension six higher derivative operator is needed, in addition to the standard bulk gauge kinetic term.

Gauge invariance and holographic renormalization

Directory of Open Access Journals (Sweden)

Keun-Young Kim

2015-10-01

Full Text Available We study the gauge invariance of physical observables in holographic theories under the local diffeomorphism. We find that gauge invariance is intimately related to the holographic renormalization: the local counter terms defined in the boundary cancel most of gauge dependences of the on-shell action as well as the divergences. There is a mismatch in the degrees of freedom between the bulk theory and the boundary one. We resolve this problem by noticing that there is a residual gauge symmetry (RGS. By extending the RGS such that it satisfies infalling boundary condition at the horizon, we can understand the problem in the context of general holographic embedding of a global symmetry at the boundary into the local gauge symmetry in the bulk.

Unveiling a spinor field classification with non-Abelian gauge symmetries

Science.gov (United States)

Fabbri, Luca; da Rocha, Roldão

2018-05-01

A spinor fields classification with non-Abelian gauge symmetries is introduced, generalizing the U(1) gauge symmetries-based Lounesto's classification. Here, a more general classification, contrary to the Lounesto's one, encompasses spinor multiplets, corresponding to non-Abelian gauge fields. The particular case of SU(2) gauge symmetry, encompassing electroweak and electromagnetic conserved charges, is then implemented by a non-Abelian spinor classification, now involving 14 mixed classes of spinor doublets. A richer flagpole, dipole, and flag-dipole structure naturally descends from this general classification. The Lounesto's classification of spinors is shown to arise as a Pauli's singlet, into this more general classification.

21 CFR 868.2610 - Gas pressure gauge.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Gas pressure gauge. 868.2610 Section 868.2610 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL... to measure gas pressure in a medical gas delivery system. (b) Classification. Class I (general...

Some physico-geometrical remarks on gauge fields

International Nuclear Information System (INIS)

Ikeda, S.

1976-01-01

The gauge fields introduced to accomplish gauge invariance under Poincare and Weyl gauge transformations in general relativity are found a new to be absorbed into the covariant derivative operators. Some torsional properties associated with them are also discussed in connection with the principle of minimally coupling and the equivalence principle

Gauge invariance and canonical quantization applied in the study of internal structure of gauge field systems

International Nuclear Information System (INIS)

Wang Fan; Chen Xiangsong; Lue Xiaofu; Sun Weiming; Goldman, T.

2010-01-01

It is unavoidable to deal with the quark and gluon momentum and angular momentum contributions to the nucleon momentum and spin in the study of nucleon internal structure. However, we never have the quark and gluon momentum, orbital angular momentum and gluon spin operators which satisfy both the gauge invariance and the canonical momentum and angular momentum commutation relations. The conflicts between the gauge invariance and canonical quantization requirement of these operators are discussed. A new set of quark and gluon momentum, orbital angular momentum and spin operators, which satisfy both the gauge invariance and canonical momentum and angular momentum commutation relations, are proposed. The key point to achieve such a proper decomposition is to separate the gauge field into the pure gauge and the gauge covariant parts. The same conflicts also exist in QED and quantum mechanics and have been solved in the same manner. The impacts of this new decomposition to the nucleon internal structure are discussed.

Particle structure of gauge theories

International Nuclear Information System (INIS)

Fredenhagen, K.

1985-11-01

The implications of the principles of quantum field theory for the particle structure of gauge theories are discussed. The general structure which emerges is compared with that of the Z 2 Higgs model on a lattice. The discussion leads to several confinement criteria for gauge theories with matter fields. (orig.)

Construction of U-gauge Green's functions of gauge theories with spontaneous symmetry breaking and Slavnov identities

International Nuclear Information System (INIS)

Flume, R.

1978-01-01

The unitary (U) gauge Green's functions of the U(1) and SU(2) Higgs-Kibble models are constructed applying a renormalized point transformation and a non-local gauge changing transformation to a manifestly renormalizable (R gauge) version of the respective theory. It is shown that the cancellation mechanism known as 'tree graph unitarity' rendering in tree graph approximation a smooth high energy behaviour of the U gauge Green's functions on mass shell can in a natural way be extended to all orders of perturbation theory. The conditions imposed by this 'generalized tree graph unitarity' on the renormalization programme are shown to be equivalent with the requirement of renormalized Slavnov identities for the R gauge Green's functions

Gravity duals of supersymmetric gauge theories on three-manifolds

International Nuclear Information System (INIS)

Farquet, Daniel; Lorenzen, Jakob; Martelli, Dario; Sparks, James

2016-01-01

We study gravity duals to a broad class of N=2 supersymmetric gauge theories defined on a general class of three-manifold geometries. The gravity backgrounds are based on Euclidean self-dual solutions to four-dimensional gauged supergravity. As well as constructing new examples, we prove in general that for solutions defined on the four-ball the gravitational free energy depends only on the supersymmetric Killing vector, finding a simple closed formula when the solution has U(1)×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.

Perturbative Quantum Gravity and its Relation to Gauge Theory

Directory of Open Access Journals (Sweden)

Bern Zvi

2002-01-01

Full Text Available In this review we describe a non-trivial relationship between perturbative gauge theory and gravity scattering amplitudes. At the semi-classical or tree-level, the scattering amplitudes of gravity theories in flat space can be expressed as a sum of products of well defined pieces of gauge theory amplitudes. These relationships were first discovered by Kawai, Lewellen, and Tye in the context of string theory, but hold more generally. In particular, they hold for standard Einstein gravity. A method based on $D$-dimensional unitarity can then be used to systematically construct all quantum loop corrections order-by-order in perturbation theory using as input thegravity tree amplitudes expressed in terms of gauge theory ones. More generally, the unitarity method provides a means for perturbatively quantizing massless gravity theories without the usual formal apparatus associated with the quantization of constrained systems. As one application, this method was used to demonstrate that maximally supersymmetric gravity is less divergent in the ultraviolet than previously thought.

Gauge-invariant cosmic structures---A dynamic systems approach

International Nuclear Information System (INIS)

Woszczyna, A.

1992-01-01

Gravitational instability is expressed in terms of the dynamic systems theory. The gauge-invariant Ellis-Bruni equation and Bardeen's equation are discussed in detail. It is shown that in an open universe filled with matter of constant sound velocity the Jeans criterion does not adequately define the length scale of the gravitational structure

Noncommutative gauge theories and Kontsevich's formality theorem

International Nuclear Information System (INIS)

Jurco, B.; Schupp, P.; Wess, J.

2001-01-01

The equivalence of star products that arise from the background field with and without fluctuations and Kontsevich's formality theorem allow an explicitly construction of a map that relates ordinary gauge theory and noncommutative gauge theory (Seiberg-Witten map.) Using noncommutative extra dimensions the construction is extended to noncommutative nonabelian gauge theory for arbitrary gauge groups; as a byproduct we obtain a 'Mini Seiberg-Witten map' that explicitly relates ordinary abelian and nonabelian gauge fields. All constructions are also valid for non-constant B-field, and even more generally for any Poisson tensor

On the gauge orbit space stratification: a review

International Nuclear Information System (INIS)

Rudolph, G.; Schmidt, M.; Volobuev, I.P.

2002-01-01

First, we review the basic mathematical structures and results concerning the gauge orbit space stratification. This includes general properties of the gauge group action, fibre bundle structures induced by this action, basic properties of the stratification and the natural Riemannian structures of the strata. In the second part, we study the stratification for theories with gauge group SU(n) in spacetime dimension 4. We develop a general method for determining the orbit types and their partial ordering, based on the 1-1 correspondence between orbit types and holonomy-induced Howe subbundles of the underlying principal SU(n)-bundle. We show that the orbit types are classified by certain cohomology elements of spacetime satisfying two relations and that the partial ordering is characterized by a system of algebraic equations. Moreover, operations for generating direct successors and direct predecessors are formulated, which allow one to construct the set of orbit types, starting from the principal type. Finally, we discuss an application to nodal configurations in Yang-Mills-Chern-Simons theory. (author)

The light-cone gauge in Polyakov's theory of strings and its relation to the conformal gauge

International Nuclear Information System (INIS)

Tzani, R.

1989-01-01

The author studies the string theory as a gauge theory. The analysis includes the formulation of the interacting bosonic string by fixing the Gervais-Sakita light-cone gauge in Polyakov's path-integral formulation of the theory and the study of the problem of changing gauge in string theory in the context of the functional formulation of the theory. The main results are the following: Mandelstam's picture is obtained from the light-cone gauge fixed Polyakov's theory. Due to the off-diagonal nature of the gauge, the calculation of the determinants differs from the usual (conformal gauge) case. The regularization of the functional integrals associated with these determinants is done by using the conformal-invariance principle. He then shows that the conformal anomaly associated with this new gauge fixing is canceled at dimensions of space-time d = 26. Studying the problem of changing gauge in string theory, he shows the equivalence between the light-cone and conformal gauge in the path-integral formulation of the theory. In particular, by performing a proper change of variables in the commuting and ghost fields in the Polyakov path-integral, the string theory in the conformal gauge is obtained from the light-cone gauge fixed expression. Finally, the problem of changing gauge is generalized to the higher genus surfaces. It is shown that the string theory in the conformal gauge is equivalent to the light-cone gauge fixed theory for surface with arbitrary number of handles

Gauge invariance of string fields

International Nuclear Information System (INIS)

Banks, T.; Peskin, M.E.

1985-10-01

Some work done to understand the appearance of gauge bosons and gravitons in string theories is reported. An action has been constructed for free (bosonic) string field theory which is invariant under an infinite set of gauge transformations which include Yang-Mills transformations and general coordinate transformations as special cases. 15 refs., 1 tab

Klein-Weyl's program and the ontology of gauge and quantum systems

Science.gov (United States)

Catren, Gabriel

2018-02-01

We distinguish two orientations in Weyl's analysis of the fundamental role played by the notion of symmetry in physics, namely an orientation inspired by Klein's Erlangen program and a phenomenological-transcendental orientation. By privileging the former to the detriment of the latter, we sketch a group(oid)-theoretical program-that we call the Klein-Weyl program-for the interpretation of both gauge theories and quantum mechanics in a single conceptual framework. This program is based on Weyl's notion of a "structure-endowed entity" equipped with a "group of automorphisms". First, we analyze what Weyl calls the "problem of relativity" in the frameworks provided by special relativity, general relativity, and Yang-Mills theories. We argue that both general relativity and Yang-Mills theories can be understood in terms of a localization of Klein's Erlangen program: while the latter describes the group-theoretical automorphisms of a single structure (such as homogenous geometries), local gauge symmetries and the corresponding gauge fields (Ehresmann connections) can be naturally understood in terms of the groupoid-theoretical isomorphisms in a family of identical structures. Second, we argue that quantum mechanics can be understood in terms of a linearization of Klein's Erlangen program. This stance leads us to an interpretation of the fact that quantum numbers are "indices characterizing representations of groups" ((Weyl, 1931a), p.xxi) in terms of a correspondence between the ontological categories of identity and determinateness.

Convexity, gauge-dependence and tunneling rates

Energy Technology Data Exchange (ETDEWEB)

Plascencia, Alexis D.; Tamarit, Carlos [Institute for Particle Physics Phenomenology, Durham University,South Road, DH1 3LE (United Kingdom)

2016-10-19

We clarify issues of convexity, gauge-dependence and radiative corrections in relation to tunneling rates. Despite the gauge dependence of the effective action at zero and finite temperature, it is shown that tunneling and nucleation rates remain independent of the choice of gauge-fixing. Taking as a starting point the functional that defines the transition amplitude from a false vacuum onto itself, it is shown that decay rates are exactly determined by a non-convex, false vacuum effective action evaluated at an extremum. The latter can be viewed as a generalized bounce configuration, and gauge-independence follows from the appropriate Nielsen identities. This holds for any election of gauge-fixing that leads to an invertible Faddeev-Popov matrix.

Convexity, gauge-dependence and tunneling rates

International Nuclear Information System (INIS)

Plascencia, Alexis D.; Tamarit, Carlos

2016-01-01

We clarify issues of convexity, gauge-dependence and radiative corrections in relation to tunneling rates. Despite the gauge dependence of the effective action at zero and finite temperature, it is shown that tunneling and nucleation rates remain independent of the choice of gauge-fixing. Taking as a starting point the functional that defines the transition amplitude from a false vacuum onto itself, it is shown that decay rates are exactly determined by a non-convex, false vacuum effective action evaluated at an extremum. The latter can be viewed as a generalized bounce configuration, and gauge-independence follows from the appropriate Nielsen identities. This holds for any election of gauge-fixing that leads to an invertible Faddeev-Popov matrix.

Duality transformation of a spontaneously broken gauge theory

International Nuclear Information System (INIS)

Mizrachi, L.

1981-04-01

Duality transformation for a spontaneously broken gauge theory is constructed in the CDS gauge (xsub(μ)Asub(μ)sup(a)=0). The dual theory is expressed in terms of dual potentials which satisfy the same gauge condition, but with g→ 1 /g. Generally the theory is not self dual but in the weak coupling region (small g), self duality is found for the subgroup which is not spontaneously broken or in regions where monopoles and vortices are concentrated (in agreement with t'Hooft's ideas that monopoles and vortices in the Georgi-Glashow model make it self dual). In the strong coupling regime a systematic strong coupling expansion can be written. For this region the dual theory is generally not local gauge invariant, but it is invariant under global gauge transformations. (author)

Canonical form of Euler-Lagrange equations and gauge symmetries

Energy Technology Data Exchange (ETDEWEB)

Geyer, B [Naturwissenschaftlich-Theoretisches Zentrum und Institut fuer Theoretische Physik, Universitaet Leipzig, Leipzig (Germany); Gitman, D M [Institute of Physics, University of Sao Paulo, Sao Paulo (Brazil); Tyutin, I V [Lebedev Physics Institute, Moscow (Russian Federation)

2003-06-13

The structure of the Euler-Lagrange equations for a general Lagrangian theory (e.g. singular, with higher derivatives) is studied. For these equations we present a reduction procedure to the so-called canonical form. In the canonical form the equations are solved with respect to highest-order derivatives of nongauge coordinates, whereas gauge coordinates and their derivatives enter the right-hand sides of the equations as arbitrary functions of time. The reduction procedure reveals constraints in the Lagrangian formulation of singular systems and, in that respect, is similar to the Dirac procedure in the Hamiltonian formulation. Moreover, the reduction procedure allows one to reveal the gauge identities between the Euler-Lagrange equations. Thus, a constructive way of finding all the gauge generators within the Lagrangian formulation is presented. At the same time, it is proved that for local theories all the gauge generators are local in time operators.

Near-field photon wave mechanics in the Lorenz gauge

International Nuclear Information System (INIS)

Keller, Ole

2007-01-01

Optical near-field interactions are studied theoretically in the perspective of photon wave mechanics paying particular attention to the dynamics in the wave-vector time domain. A unitary transformation is used to replace the scalar and longitudinal photon variables by so-called near-field and gauge photon variables. Dynamical equations are established for these types of photon variables, and it is shown that these equations are invariant against gauge transformations within the Lorenz gauge. The near-field photon is absent in the free-field limit, and the gauge photon can be eliminated by a suitable gauge transformation. Implicit solutions for the near-field, gauge, and transverse photon variables are obtained and discussed. The general theory is applied to an investigation of transverse photon propagation in a uniform solid-state plasma dominated by the diamagnetic field-matter interaction. It is found that the diamagnetic response can be incorporated in a quantum mechanical wave equation for a massive transverse photon. The Compton wave number of the massive photon equals the plasma wave number of the electron system. A dynamical equation describing the emission of a massive transverse photon from a mesoscopic source embedded in the plasma is finally established

Application of MySQL in instantaneous profile gauge system

International Nuclear Information System (INIS)

Guo Xiaojing; Miao Jichen; Wu Zhifang

2011-01-01

As equipment in the hot rolling plate plant for online measurement of strip steel, the instantaneous profile gauge is used to measure instant crown of hot rolling strips and feed back the crown to the rolling mill to adjust strip profile. During the measurement, a large amount of data need to be stored reasonably for query, display, computation and other processing, while a database management software can make it happen. Based on such features of MySQL as small size, fast speed, low cost and open source codes, a database function was implemented in the instantaneous profile gauge for data storage, query and maintenance, by applying MySQL database management system and integrating with the control interface. (authors)

Refined algebraic quantisation in a system with nonconstant gauge invariant structure functions

International Nuclear Information System (INIS)

Martínez-Pascual, Eric

2013-01-01

In a previous work [J. Louko and E. Martínez-Pascual, “Constraint rescaling in refined algebraic quantisation: Momentum constraint,” J. Math. Phys. 52, 123504 (2011)], refined algebraic quantisation (RAQ) within a family of classically equivalent constrained Hamiltonian systems that are related to each other by rescaling one momentum-type constraint was investigated. In the present work, the first steps to generalise this analysis to cases where more constraints occur are developed. The system under consideration contains two momentum-type constraints, originally abelian, where rescalings of these constraints by a non-vanishing function of the coordinates are allowed. These rescalings induce structure functions at the level of the gauge algebra. Providing a specific parametrised family of real-valued scaling functions, the implementation of the corresponding rescaled quantum momentum-type constraints is performed using RAQ when the gauge algebra: (i) remains abelian and (ii) undergoes into an algebra of a nonunimodular group with nonconstant gauge invariant structure functions. Case (ii) becomes the first example known to the author where an open algebra is handled in refined algebraic quantisation. Challenging issues that arise in the presence of non-gauge invariant structure functions are also addressed

Renormalization of gauge theories without cohomology

International Nuclear Information System (INIS)

Anselmi, Damiano

2013-01-01

We investigate the renormalization of gauge theories without assuming cohomological properties. We define a renormalization algorithm that preserves the Batalin-Vilkovisky master equation at each step and automatically extends the classical action till it contains sufficiently many independent parameters to reabsorb all divergences into parameter-redefinitions and canonical transformations. The construction is then generalized to the master functional and the field-covariant proper formalism for gauge theories. Our results hold in all manifestly anomaly-free gauge theories, power-counting renormalizable or not. The extension algorithm allows us to solve a quadratic problem, such as finding a sufficiently general solution of the master equation, even when it is not possible to reduce it to a linear (cohomological) problem. (orig.)

Gauged Hamiltonians for free particle on surfaces in configuration and phase spaces

Directory of Open Access Journals (Sweden)

M Dehghani

2016-06-01

Full Text Available We present a method to gauge second class systems consisted of two constraints in the chain structure. In this method we added a momentum counterpart of Wess Zumino coordinate to primary constraint and used the first class condition to find a new and gauged Hamiltonian. Primary constraints were assumed as identities in configuration and phase space and we tried to find general Hamiltonians

Ghost number anomaly in the Polyakov's light-cone gauge

International Nuclear Information System (INIS)

Suzuki, Hiroshi.

1990-06-01

The conformal (Weyl) anomaly of the ghost-anti-ghost system in the two-dimentional quantum gravity is calculated. A background covariant formalism allows us to treat the Polyakov's light-cone gauge in a systematic way. The anomaly gives a contribution to the central charge, -28, which agrees with the result of Kniznik, Polyakov and Zamolodchikov. The ghost number anomaly is also calculated, and the metric corrections to the naive ghost number current are given. It is suggested that a general scalar density in the light-cone gauge carries a screening ghost number. (author)

Theorems for asymptotic safety of gauge theories

Energy Technology Data Exchange (ETDEWEB)

Bond, Andrew D.; Litim, Daniel F. [University of Sussex, Department of Physics and Astronomy, Brighton (United Kingdom)

2017-06-15

We classify the weakly interacting fixed points of general gauge theories coupled to matter and explain how the competition between gauge and matter fluctuations gives rise to a rich spectrum of high- and low-energy fixed points. The pivotal role played by Yukawa couplings is emphasised. Necessary and sufficient conditions for asymptotic safety of gauge theories are also derived, in conjunction with strict no go theorems. Implications for phase diagrams of gauge theories and physics beyond the Standard Model are indicated. (orig.)

Gauge fixing problem in the conformal QED

International Nuclear Information System (INIS)

Ichinose, Shoichi

1986-01-01

The gauge fixing problem in the conformal (spinor and scalar) QED is examined. For the analysis, we generalize Dirac's manifestly conformal-covariant formalism. It is shown that the (vector and matter) fields must obey a certain mixed (conformal and gauge) type of transformation law in order to fix the local gauge symmetry preserving the conformal invariance in the Lagrangian. (orig.)

Energy-efficient strain gauges for the wireless condition monitoring systems in mechanical engineering

Energy Technology Data Exchange (ETDEWEB)

Berndt, Michael; Fellner, Thomas; Zeiser, Roderich; Wilde, Juergen [Freiburg Univ. (Germany). Dept. for Microsystems Engineering (IMTEK)

2012-07-01

This work focuses on the development of novel strain gauges, which are suited for the operation in autonomous wireless condition monitoring systems. For this purpose, capacitive as well as highly resistive strain gauges were designed and fabricated. The C- and R-sensors were utilised in combination with demonstration circuits, which integrate the circuits for instrumentation, A/D-conversion and furthermore comprise a microcontroller with a wireless transceiver system, all on a small separate printed wiring board. (orig.)

Definition and general properties of the transfer matrix in continuum limit improved lattice gauge theories

International Nuclear Information System (INIS)

Luescher, M.; Weisz, P.

1984-02-01

When operators of dimension 6 are added to the standard Wilson action in lattice gauge theories, physical positivity is lost in general. We show that a transfer matrix can nevertheless be defined. Its properties are, however, unusual: complex eigenvalues may occur (leading to damped oscillatory behaviour of correlation functions), and there are always contributions in the spectral decomposition of two-point functions that come with a negative weight. (orig.)

Coarse-graining free theories with gauge symmetries: the linearized case

International Nuclear Information System (INIS)

Bahr, Benjamin; Dittrich, Bianca; He Song

2011-01-01

Discretizations of continuum theories often do not preserve the gauge symmetry content. This occurs in particular for diffeomorphism symmetry in general relativity, which leads to severe difficulties in both canonical and covariant quantization approaches. We discuss here the method of perfect actions, which attempts to restore gauge symmetries by mirroring exactly continuum physics on a lattice via a coarse graining process. Analytical results can only be obtained via a perturbative approach, for which we consider the first step, namely the coarse graining of the linearized theory. The linearized gauge symmetries are exact also in the discretized theory; hence, we develop a formalism to deal with gauge systems. Finally, we provide a discretization of linearized gravity as well as a coarse graining map and show that with this choice the three-dimensional (3D) linearized gravity action is invariant under coarse graining.

Introduction to gauge theories of electroweak interactions

International Nuclear Information System (INIS)

Ecker, G.

1982-01-01

The author presents an introduction to electroweak gauge theories. Emphasis is placed on the properties of a general gauge theory. The standard model is discussed as the simplest example to illustrate these properties. (G.T.H.)

Noncommutative SO(n) and Sp(n) gauge theories

International Nuclear Information System (INIS)

Bonora, L.; INFN, Sezione di Trieste, Trieste; Schnabl, M.; INFN, Sezione di Trieste, Trieste; Sheikh-Jabbari, M.M.; Tomasiello, A.

2000-08-01

We study the generalization of noncommutative gauge theories to the case of orthogonal and symplectic groups. We find out that this is possible, since we are allowed to define orthogonal and symplectic subgroups of noncommutative unitary gauge transformations even though the gauge potentials and gauge transformations are not valued in the orthogonal and symplectic subalgebras of the Lie algebra of antihermitean matrices. Our construction relies on an antiautomorphism of the basic noncommutative algebra of functions which generalizes the charge conjugation operator of ordinary field theory. We show that the corresponding noncommutative picture from low energy string theory is obtained via orientifold projection in the presence of a non-trivial NSNS B-field. (author)

Renormalizable Non-Covariant Gauges and Coulomb Gauge Limit

CERN Document Server

Baulieu, L

1999-01-01

To study ``physical'' gauges such as the Coulomb, light-cone, axial or temporal gauge, we consider ``interpolating'' gauges which interpolate linearly between a covariant gauge, such as the Feynman or Landau gauge, and a physical gauge. Lorentz breaking by the gauge-fixing term of interpolating gauges is controlled by extending the BRST method to include not only the local gauge group, but also the global Lorentz group. We enumerate the possible divergences of interpolating gauges, and show that they are renormalizable, and we show that the expectation value of physical observables is the same as in a covariant gauge. In the second part of the article we study the Coulomb-gauge as the singular limit of the Landau-Coulomb interpolating gauge. We find that unrenormalized and renormalized correlation functions are finite in this limit. We also find that there are finite two-loop diagrams of ``unphysical'' particles that are not present in formal canonical quantization in the Coulomb gauge. We verify that in the ...

An elementary introduction to the Gauge theory approach to gravity. 23

International Nuclear Information System (INIS)

Mukunda, N.

1989-01-01

Can all the forces be unified by a gauge group? Can we get a clue by studying gravity itself which is also a gauge theory by gauging the Poincare group?. The main problems have been in the understanding of the role of invariants of the Lie algebra of the group if one has general covariance. One is led to theories more general than general relativity in that, in addition to curvature, one also has torsion. These and other aspects of gravitation as a gauge theory are treated. (author). 11 refs.; 1 fig

Diagrammatic cancellations and the gauge dependence of QED

Energy Technology Data Exchange (ETDEWEB)

Kißler, Henry, E-mail: kissler@physik.hu-berlin.de [Department of Mathematical Sciences, University of Liverpool, L69 7ZL, Liverpool (United Kingdom); Department of Mathematics, Humboldt-Universität zu Berlin, Rudower Chaussee 25, D-12489 Berlin (Germany); Kreimer, Dirk, E-mail: kreimer@math.hu-berlin.de [Department of Mathematics, Humboldt-Universität zu Berlin, Rudower Chaussee 25, D-12489 Berlin (Germany)

2017-01-10

This letter examines diagrammatic cancellations for Quantum Electrodynamics (QED) in the general linear gauge. These cancellations combine Feynman graphs of various topologies and provide a method to reconstruct the gauge dependence of the electron propagator from the result of a particular gauge by means of a linear Dyson–Schwinger equation. We use this method in combination with dimensional regularization to demonstrate how the 3-loop ε-expansion in the Feynman gauge determines the ε-expansions for all gauge parameter dependent terms to 4 loops.

Gauge structure of neutral-vector field theory. [Massive vector fields, massless limits

Energy Technology Data Exchange (ETDEWEB)

Kubo, R; Yokoyama, [Hiroshima univ., Takehara (Japan). Research Inst. for Theoretical Physics

1975-03-01

General aspects of gauge structure of neutral-vector field theory are investigated from an extended standpoint, where massive vector fields are treated in a form corresponding to the electromagnetic fields in a general gauge formalism reported previously. All results obtained are shown to have unique massless limits. It is shown that a generalized q-number gauge transformation for fields makes the theory invariant in cooperation with a simultaneous transformation for relevant gauge parameters. A method of differentiation with respect to a gauge variable is found to clarify some essential features of the gauge structure. Two possible types of gauge structure also emerge correspondingly to the massless case. A neutral-vector field theory proposed in a preceding paper is included in the present framework as the most preferable case.

Unitary Representations of Gauge Groups

Science.gov (United States)

Huerfano, Ruth Stella

I generalize to the case of gauge groups over non-trivial principal bundles representations that I. M. Gelfand, M. I. Graev and A. M. Versik constructed for current groups. The gauge group of the principal G-bundle P over M, (G a Lie group with an euclidean structure, M a compact, connected and oriented manifold), as the smooth sections of the associated group bundle is presented and studied in chapter I. Chapter II describes the symmetric algebra associated to a Hilbert space, its Hilbert structure, a convenient exponential and a total set that later play a key role in the construction of the representation. Chapter III is concerned with the calculus needed to make the space of Lie algebra valued 1-forms a Gaussian L^2-space. This is accomplished by studying general projective systems of finitely measurable spaces and the corresponding systems of sigma -additive measures, all of these leading to the description of a promeasure, a concept modeled after Bourbaki and classical measure theory. In the case of a locally convex vector space E, the corresponding Fourier transform, family of characters and the existence of a promeasure for every quadratic form on E^' are established, so the Gaussian L^2-space associated to a real Hilbert space is constructed. Chapter III finishes by exhibiting the explicit Hilbert space isomorphism between the Gaussian L ^2-space associated to a real Hilbert space and the complexification of its symmetric algebra. In chapter IV taking as a Hilbert space H the L^2-space of the Lie algebra valued 1-forms on P, the gauge group acts on the motion group of H defining in an straight forward fashion the representation desired.

Gauge-invariant variational methods for Hamiltonian lattice gauge theories

International Nuclear Information System (INIS)

Horn, D.; Weinstein, M.

1982-01-01

This paper develops variational methods for calculating the ground-state and excited-state spectrum of Hamiltonian lattice gauge theories defined in the A 0 = 0 gauge. The scheme introduced in this paper has the advantage of allowing one to convert more familiar tools such as mean-field, Hartree-Fock, and real-space renormalization-group approximation, which are by their very nature gauge-noninvariant methods, into fully gauge-invariant techniques. We show that these methods apply in the same way to both Abelian and non-Abelian theories, and that they are at least powerful enough to describe correctly the physics of periodic quantum electrodynamics (PQED) in (2+1) and (3+1) space-time dimensions. This paper formulates the problem for both Abelian and non-Abelian theories and shows how to reduce the Rayleigh-Ritz problem to that of computing the partition function of a classical spin system. We discuss the evaluation of the effective spin problem which one derives the PQED and then discuss ways of carrying out the evaluation of the partition function for the system equivalent to a non-Abelian theory. The explicit form of the effective partition function for the non-Abelian theory is derived, but because the evaluation of this function is considerably more complicated than the one derived in the Abelian theory no explicit evaluation of this function is presented. However, by comparing the gauge-projected Hartree-Fock wave function for PQED with that of the pure SU(2) gauge theory, we are able to show that extremely interesting differences emerge between these theories even at this simple level. We close with a discussion of fermions and a discussion of how one can extend these ideas to allow the computation of the glueball and hadron spectrum

Two-time physics with gravitational and gauge field backgrounds

International Nuclear Information System (INIS)

Bars, Itzhak

2000-01-01

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

'Baldin autumn' and gauge fields

International Nuclear Information System (INIS)

Konopleva, N.P.

2008-01-01

The paper is the reminiscences of the participant of the gauge field theory beginning and the first 'Baldin Autumn' conference in 1969. This conference was named 'Vector Mesons and Electromagnetic Interactions'. At that time, just the processes with vector mesons participation contained some experimental indications of new universal interactions existence. Vector dominance was the experimental evidence of physical reasons of the gauge field theory. In the course of time the gauge field theory form, which was under discussion thirty seven years ago, became generally recognized and experimentally corroborated. It led to construction of the well-known Standard Model of elementary particle interactions

Tracking gauge symmetry factorizability on intervals

International Nuclear Information System (INIS)

Ngoc-Khanh Tran

2006-01-01

We track the gauge symmetry breaking pattern by boundary conditions on fifth and higher-dimensional intervals. It is found that, with Dirichlet-Neumann boundary conditions, the Kaluza-Klein decomposition in five-dimension for arbitrary gauge group can always be factorized into that for separate subsets of at most two gauge symmetries, and so is completely solvable. Accordingly, we present a simple and systematic geometric method to unambiguously identify the gauge breaking/mixing content by general set of Dirichlet-Neumann boundary conditions. We then formulate a limit theorem on gauge symmetry factorizability to recapitulate this interesting feature. Albeit the breaking/mixing, a particularly simple check of orthogonality and normalization of fields' modes in effective 4-dim picture is explicitly obtained. An interesting chained-mixing of gauge symmetries in higher dimensions by Dirichlet-Neumann boundary conditions is also explicitly constructed. This study has direct applications to higgsless/GUT model building

Hidden QCD in Chiral Gauge Theories

DEFF Research Database (Denmark)

Ryttov, Thomas; Sannino, Francesco

2005-01-01

The 't Hooft and Corrigan-Ramond limits of massless one-flavor QCD consider the two Weyl fermions to be respectively in the fundamental representation or the two index antisymmetric representation of the gauge group. We introduce a limit in which one of the two Weyl fermions is in the fundamental...... representation and the other in the two index antisymmetric representation of a generic SU(N) gauge group. This theory is chiral and to avoid gauge anomalies a more complicated chiral theory is needed. This is the generalized Georgi-Glashow model with one vector like fermion. We show that there is an interesting...... phase in which the considered chiral gauge theory, for any N, Higgses via a bilinear condensate: The gauge interactions break spontaneously to ordinary massless one-flavor SU(3) QCD. The additional elementary fermionic matter is uncharged under this SU(3) gauge theory. It is also seen that when...

Measurability of non-abelium gauge fields

Energy Technology Data Exchange (ETDEWEB)

Ivanenko, D.D.; Obukhov, Yu.N.

New estimations of the accuracy of measurement of non-abeliar gauge field components are obtained on the base of qualitative analysis of the test body equations of motion. They generalize the Bohr and Rosenfeld results on the measurability of an electomagnetic field for the case of an arbitrary gauge group.

Gauge transformations in relativistic two-particle constraint theory

International Nuclear Information System (INIS)

Jallouli, H.; Sazdjian, H.

1996-01-01

The forms of the local potentials in linear covariant gauges are investigated and relationships are found between them. The gauge transformation properties of the Green's function and of the Bethe-Salpeter wave function are reviewed. The infinitesimal gauge transformation laws of the constraint theory wave functions and potentials are determined. The case of the local approximation of potentials is considered. The general properties of the gauge transformations in the local approximation are studied. (K.A.)

Tensor gauge condition and tensor field decomposition

Science.gov (United States)

Zhu, Ben-Chao; Chen, Xiang-Song

2015-10-01

We discuss various proposals of separating a tensor field into pure-gauge and gauge-invariant components. Such tensor field decomposition is intimately related to the effort of identifying the real gravitational degrees of freedom out of the metric tensor in Einstein’s general relativity. We show that as for a vector field, the tensor field decomposition has exact correspondence to and can be derived from the gauge-fixing approach. The complication for the tensor field, however, is that there are infinitely many complete gauge conditions in contrast to the uniqueness of Coulomb gauge for a vector field. The cause of such complication, as we reveal, is the emergence of a peculiar gauge-invariant pure-gauge construction for any gauge field of spin ≥ 2. We make an extensive exploration of the complete tensor gauge conditions and their corresponding tensor field decompositions, regarding mathematical structures, equations of motion for the fields and nonlinear properties. Apparently, no single choice is superior in all aspects, due to an awkward fact that no gauge-fixing can reduce a tensor field to be purely dynamical (i.e. transverse and traceless), as can the Coulomb gauge in a vector case.

Reducible gauge theories in local superfield Lagrangian BRST quantization

Energy Technology Data Exchange (ETDEWEB)

Gitman, D. M. [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Fisica; Moshin, P.Yu. [Tomsk State Pedagogical University (Russian Federation); Reshetnyak, A.A. [Inst. of Strength Physics and Materials Science, Tomsk (Russian Federation). Lab. of Non-equilibrium State Theory

2007-12-15

The construction of {theta}-local superfield Lagrangian BRST quantization in non-Abelian hyper gauges for generic gauge theories based on the action principle is examined in the case of reducible local superfield models (LSM) on the basis of embedding a gauge theory into a special {theta}-local superfield model with anti symplectic constraints and a Grassmann-odd time parameter {theta}. We examine the problem of establishing a new correspondence between the odd-Lagrangian and odd-Hamiltonian formulations of a local LSM in the case of degeneracy of the Lagrangian description with respect to derivatives over {theta} of generalized classical superfields A{sup I}({theta}). We also reveal the role of the nilpotent BRST-BFV charge for a formal dynamical system corresponding to the BV-BFV dual description of an LSM. (author)

A photon propagator on de Sitter in covariant gauges

NARCIS (Netherlands)

Domazet, S.; Prokopec, T.

2014-01-01

We construct a de Sitter invariant photon propagator in general covariant gauges. Our result is a natural generalization of the Allen-Jacobson photon propagator in Feynman gauge. Our propagator reproduces the correct response to a point static charge and the one-loop electromagnetic stress-energy

Gauge-free gyrokinetic theory

Science.gov (United States)

Burby, Joshua; Brizard, Alain

2017-10-01

Test-particle gyrocenter equations of motion play an essential role in the diagnosis of turbulent strongly-magnetized plasmas, and are playing an increasingly-important role in the formulation of kinetic-gyrokinetic hybrid models. Previous gyrocenter models required the knowledge of the perturbed electromagnetic potentials, which are not directly observable quantities (since they are gauge-dependent). A new gauge-free formulation of gyrocenter motion is presented, which enables gyrocenter trajectories to be determined using only measured values of the directly-observable electromagnetic field. Our gauge-free gyrokinetic theory is general enough to allow for gyroradius-scale fluctuations in both the electric and magnetic field. In addition, we provide gauge-free expressions for the charge and current densities produced by a distribution of gyrocenters, which explicitly include guiding-center and gyrocenter polarization and magnetization effects. This research was supported by the U.S. DOE Contract Nos. DE-SC0014032 (AB) and DE-AC05-06OR23100 (JB).

A gauge invariant theory for time dependent heat current

International Nuclear Information System (INIS)

Chen, Jian; ShangGuan, Minhui; Wang, Jian

2015-01-01

In this work, we develop a general gauge-invariant theory for AC heat current through multi-probe systems. Using the non-equilibrium Green’s function, a general expression for time-dependent electrothermal admittance is obtained where we include the internal potential due to the Coulomb interaction explicitly. We show that the gauge-invariant condition is satisfied for heat current if the self-consistent Coulomb interaction is considered. It is known that the Onsager relation holds for dynamic charge conductance. We show in this work that the Onsager relation for electrothermal admittance is violated, except for a special case of a quantum dot system with a single energy level. We apply our theory to a nano capacitor where the Coulomb interaction plays an essential role. We find that, to the first order in frequency, the heat current is related to the electrochemical capacitance as well as the phase accumulated in the scattering event. (paper)

Spin dynamics under local gauge fields in chiral spin-orbit coupling systems

International Nuclear Information System (INIS)

Tan, S.G.; Jalil, M.B.A.; Fujita, T.; Liu, X.J.

2011-01-01

Research highlights: → We derive a modified LLG equation in magnetic systems with spin-orbit coupling (SOC). → Our results are applied to magnetic multilayers, and DMS and magnetic Rashba systems. → SOC mediated magnetization switching is predicted in rare earth metals (large SOC). → The magnetization trajectory and frequency can be modulated by applied voltage. → This facilitates potential application as tunable microwave oscillators. - Abstract: We present a theoretical description of local spin dynamics in magnetic systems with a chiral spin texture and finite spin-orbit coupling (SOC). Spin precession about the relativistic effective magnetic field in a SOC system gives rise to a non-Abelian SU(2) gauge field reminiscent of the Yang-Mills field. In addition, the adiabatic relaxation of electron spin along the local spin yields an U(1) x U(1) topological gauge (Berry) field. We derive the corresponding equation of motion i.e. modified Landau-Lifshitz-Gilbert (LLG) equation, for the local spin under the influence of these effects. Focusing on the SU(2) gauge, we obtain the spin torque magnitude, and the amplitude and frequency of spin oscillations in this system. Our theoretical estimates indicate significant spin torque and oscillations in systems with large spin-orbit coupling, which may be utilized in technological applications such as current-induced magnetization-switching and tunable microwave oscillators.

Light-induced gauge fields for ultracold atoms

Science.gov (United States)

Goldman, N.; Juzeliūnas, G.; Öhberg, P.; Spielman, I. B.

2014-12-01

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

Light-induced gauge fields for ultracold atoms

International Nuclear Information System (INIS)

Goldman, N; Juzeliūnas, G; Öhberg, P; Spielman, I B

2014-01-01

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

Composite gauge bosons of transmuted gauge symmetry

International Nuclear Information System (INIS)

Terazawa, Hidezumi.

1987-10-01

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

Gauge-transformation properties of cosmological observables and its application to the light-cone average

International Nuclear Information System (INIS)

Yoo, Jaiyul; Durrer, Ruth

2017-01-01

Theoretical descriptions of observable quantities in cosmological perturbation theory should be independent of coordinate systems. This statement is often referred to as gauge-invariance of observable quantities, and the sanity of their theoretical description is verified by checking its gauge-invariance. We argue that cosmological observables are invariant scalars under diffeomorphisms and their theoretical description is gauge-invariant, only at linear order in perturbations. Beyond linear order, they are usually not gauge-invariant, and we provide the general law for the gauge-transformation that the perturbation part of an observable does obey. We apply this finding to derive the second-order expression for the observational light-cone average in cosmology and demonstrate that our expression is indeed invariant under diffeomorphisms.

Gauge-transformation properties of cosmological observables and its application to the light-cone average

Energy Technology Data Exchange (ETDEWEB)

Yoo, Jaiyul [Center for Theoretical Astrophysics and Cosmology, Institute for Computational Science, University of Zürich, Winterthurerstrasse 190, CH-8057, Zürich (Switzerland); Durrer, Ruth, E-mail: jyoo@physik.uzh.ch, E-mail: ruth.durrer@unige.ch [Département de Physique Théorique and Center for Astroparticle Physics, Université de Genève, Quai E. Ansermet 24, CH-1211 Genève 4 (Switzerland)

2017-09-01

Theoretical descriptions of observable quantities in cosmological perturbation theory should be independent of coordinate systems. This statement is often referred to as gauge-invariance of observable quantities, and the sanity of their theoretical description is verified by checking its gauge-invariance. We argue that cosmological observables are invariant scalars under diffeomorphisms and their theoretical description is gauge-invariant, only at linear order in perturbations. Beyond linear order, they are usually not gauge-invariant, and we provide the general law for the gauge-transformation that the perturbation part of an observable does obey. We apply this finding to derive the second-order expression for the observational light-cone average in cosmology and demonstrate that our expression is indeed invariant under diffeomorphisms.

Absence of the Gribov ambiguity in a special algebraic gauge

Directory of Open Access Journals (Sweden)

Raval Haresh

2016-01-01

Full Text Available The Gribov ambiguity exists in various gauges except algebraic gauges. However in general, algebraic gauges are not Lorentz invariant, which is their fundamental flaw. Here we discuss a quadratic gauge fixing, which is Lorentz invariant. We show that nontrivial copies can not occur in this gauge. We then provide an example of spherically symmetric gauge field configuration and prove that with a proper boundary condition on the configuration, this gauge removes the ambiguity on a compact manifold S3${{\\mathbb S}^3}$.

A gauge-theoretic approach to gravity.

Science.gov (United States)

Krasnov, Kirill

2012-08-08

Einstein's general relativity (GR) is a dynamical theory of the space-time metric. We describe an approach in which GR becomes an SU(2) gauge theory. We start at the linearized level and show how a gauge-theoretic Lagrangian for non-interacting massless spin two particles (gravitons) takes a much more simple and compact form than in the standard metric description. Moreover, in contrast to the GR situation, the gauge theory Lagrangian is convex. We then proceed with a formulation of the full nonlinear theory. The equivalence to the metric-based GR holds only at the level of solutions of the field equations, that is, on-shell. The gauge-theoretic approach also makes it clear that GR is not the only interacting theory of massless spin two particles, in spite of the GR uniqueness theorems available in the metric description. Thus, there is an infinite-parameter class of gravity theories all describing just two propagating polarizations of the graviton. We describe how matter can be coupled to gravity in this formulation and, in particular, how both the gravity and Yang-Mills arise as sectors of a general diffeomorphism-invariant gauge theory. We finish by outlining a possible scenario of the ultraviolet completion of quantum gravity within this approach.

Gravitating SO (3,1) gauge field

International Nuclear Information System (INIS)

Aragone, C.; Restuccia, A.

1978-01-01

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

Geometric phases and hidden local gauge symmetry

International Nuclear Information System (INIS)

Fujikawa, Kazuo

2005-01-01

The analysis of geometric phases associated with level crossing is reduced to the familiar diagonalization of the Hamiltonian in the second quantized formulation. A hidden local gauge symmetry, which is associated with the arbitrariness of the phase choice of a complete orthonormal basis set, becomes explicit in this formulation (in particular, in the adiabatic approximation) and specifies physical observables. The choice of a basis set which specifies the coordinate in the functional space is arbitrary in the second quantization, and a subclass of coordinate transformations, which keeps the form of the action invariant, is recognized as the gauge symmetry. We discuss the implications of this hidden local gauge symmetry in detail by analyzing geometric phases for cyclic and noncyclic evolutions. It is shown that the hidden local symmetry provides a basic concept alternative to the notion of holonomy to analyze geometric phases and that the analysis based on the hidden local gauge symmetry leads to results consistent with the general prescription of Pancharatnam. We however note an important difference between the geometric phases for cyclic and noncyclic evolutions. We also explain a basic difference between our hidden local gauge symmetry and a gauge symmetry (or equivalence class) used by Aharonov and Anandan in their definition of generalized geometric phases

Gauging the twisted Poincare symmetry as a noncommutative theory of gravitation

International Nuclear Information System (INIS)

Chaichian, M.; Tureanu, A.; Oksanen, M.; Zet, G.

2009-01-01

Einstein's theory of general relativity was formulated as a gauge theory of Lorentz symmetry by Utiyama in 1956, while the Einstein-Cartan gravitational theory was formulated by Kibble in 1961 as the gauge theory of Poincare transformations. In this framework, we propose a formulation of the gravitational theory on canonical noncommutative space-time by covariantly gauging the twisted Poincare symmetry, in order to fulfil the requirement of covariance under the general coordinate transformations, an essential ingredient of the theory of general relativity. It appears that the twisted Poincare symmetry cannot be gauged by generalizing the Abelian twist to a covariant non-Abelian twist, nor by introducing a more general covariant twist element. The advantages of such a formulation as well as the related problems are discussed and possible ways out are outlined.

Geometrodynamics of gauge fields on the geometry of Yang-Mills and gravitational gauge theories

CERN Document Server

Mielke, Eckehard W

2016-01-01

This monograph aims to provide a unified, geometrical foundation of gauge theories of elementary particle physics. The underlying geometrical structure is unfolded in a coordinate-free manner via the modern mathematical notions of fibre bundles and exterior forms. Topics such as the dynamics of Yang-Mills theories, instanton solutions and topological invariants are included. By transferring these concepts to local space-time symmetries, generalizations of Einstein's theory of gravity arise in a Riemann-Cartan space with curvature and torsion. It provides the framework in which the (broken) Poincaré gauge theory, the Rainich geometrization of the Einstein-Maxwell system, and higher-dimensional, non-abelian Kaluza-Klein theories are developed. Since the discovery of the Higgs boson, concepts of spontaneous symmetry breaking in gravity have come again into focus, and, in this revised edition, these will be exposed in geometric terms. Quantizing gravity remains an open issue: formulating it as a de Sitter t...

Gyrocenter-gauge kinetic theory

International Nuclear Information System (INIS)

Qin, H.; Tang, W.M.; Lee, W.W.

2000-01-01

Gyrocenter-gauge kinetic theory is developed as an extension of the existing gyrokinetic theories. In essence, the formalism introduced here is a kinetic description of magnetized plasmas in the gyrocenter coordinates which is fully equivalent to the Vlasov-Maxwell system in the particle coordinates. In particular, provided the gyroradius is smaller than the scale-length of the magnetic field, it can treat high frequency range as well as the usual low frequency range normally associated with gyrokinetic approaches. A significant advantage of this formalism is that it enables the direct particle-in-cell simulations of compressional Alfven waves for MHD applications and of RF waves relevant to plasma heating in space and laboratory plasmas. The gyrocenter-gauge kinetic susceptibility for arbitrary wavelength and arbitrary frequency electromagnetic perturbations in a homogeneous magnetized plasma is shown to recover exactly the classical result obtained by integrating the Vlasov-Maxwell system in the particle coordinates. This demonstrates that all the waves supported by the Vlasov-Maxwell system can be studied using the gyrocenter-gauge kinetic model in the gyrocenter coordinates. This theoretical approach is so named to distinguish it from the existing gyrokinetic theory, which has been successfully developed and applied to many important low-frequency and long parallel wavelength problems, where the conventional meaning of gyrokinetic has been standardized. Besides the usual gyrokinetic distribution function, the gyrocenter-gauge kinetic theory emphasizes as well the gyrocenter-gauge distribution function, which sometimes contains all the physics of the problems being studied, and whose importance has not been realized previously. The gyrocenter-gauge distribution function enters Maxwell's equations through the pull-back transformation of the gyrocenter transformation, which depends on the perturbed fields. The efficacy of the gyrocenter-gauge kinetic approach is

Problem of ''global color'' in gauge theories

International Nuclear Information System (INIS)

Horvathy, P.A.; Rawnsley, J.H.; UER de Mathematique, Universite de Provence, Marseille, France)

1986-01-01

The problem of ''global color'' (which arose recently in monopole theory) is generalized to arbitrary gauge theories: a subgroup K of the ''unbroken'' gauge group G is implementable iff the gauge bundle reduces to the centralizer of K in G. Equivalent implementations correspond to equivalent reductions. Such an action is an internal symmetry for a given configuration iff the Yang-Mills field reduces also. The case of monopoles is worked out in detail

The holomorphicity of the gauge coupling constant in supersymmetric gauge theories

International Nuclear Information System (INIS)

Li, H.

1993-01-01

Holomorphicity is the analytical dependence of the gauge coupling function, f = 1/g 2 + Θ/8π 2 , on the chiral fields in supergravity and supersymmetric gauge theories. The holomorphic property of 1/g 2 in supersymmetric gauge theories is studied by calculating its dependence on the mass matrix. The general representations of the mass matrix allowed by the constraints of gauge invariance is considered, and calculate the one- and two-loop corrections to 1/g 2 for both super QED and super Yang-Mills theories. For the massive mass matrix it is shown that one- and two-loop corrections to the gauge coupling constant are holomorphic. The reason for two-loop holomorphicity is that the second order logarithmic terms cancel out. For the mass matrix with at least one zero mode, it is recognized that there are two distinct cases which we call pseudo massive and intrinsically massless. For the case of pseudo mass matrix, the reducible representation of the gauge group is (i) complex with equal numbers of irreducible representations and their conjugates, (ii) real, or (iii) pseudo-real. Even though there are massless modes, it is found that the dependence of the gauge coupling constant on the mass matrix is holomorphic. This holomorphicity follows because the mass matrix can be perturbed to regularize the infrared divergence. For the case of intrinsically massless mass matrix, a reducible complex representation with unequal numbers of irreducible representations and their conjugates. The author shows that loop corrections to the gauge coupling constant are non-holomorphic. The reason is an infrared momentum cutoff is used which spins holomorphicity. The results show that, for the pseudo massive case, even though there is an infrared divergence, the one- and two-loop corrections are still holomorphic. Hence, it is concluded that non-holomorphicity is caused by the unbalanced numbers of families and antifamilies in the complex representation

Nanocomposite Strain Gauges Having Small TCRs

Science.gov (United States)

Gregory, Otto; Chen, Ximing

2009-01-01

Ceramic strain gauges in which the strain-sensitive electrically conductive strips made from nanocomposites of noble metal and indium tin oxide (ITO) are being developed for use in gas turbine engines and other power-generation systems in which gas temperatures can exceed 1,500 F (about 816 C). In general, strain gauges exhibit spurious thermally induced components of response denoted apparent strain. When temperature varies, a strain-gauge material that has a nonzero temperature coefficient of resistance (TCR) exhibits an undesired change in electrical resistance that can be mistaken for the change in resistance caused by a change in strain. It would be desirable to formulate straingauge materials having TCRs as small as possible so as to minimize apparent strain. Most metals exhibit positive TCRs, while most semiconductors, including ITO, exhibit negative TCRs. The present development is based on the idea of using the negative TCR of ITO to counter the positive TCRs of noble metals and of obtaining the benefit of the ability of both ITO and noble metals to endure high temperatures. The noble metal used in this development thus far has been platinum. Combinatorial libraries of many ceramic strain gauges containing nanocomposites of various proportions of ITO and platinum were fabricated by reactive co-sputtering from ITO and platinum targets onto alumina- and zirconia-based substrates mounted at various positions between the targets.

The Higgs mechanism in a covariant-gauge formalism

International Nuclear Information System (INIS)

Yokoyama, Kan-ichi; Kubo, Reijiro.

1975-02-01

In a covariant-gauge formalism for gauge fields the Higgs mechanism is investigated under a spontaneous breakdown of gauge invariance. It is shown that the Goldstone bosons are in general described by a dipole-ghost field and can be consistently eliminated from the physical state-vector space by supplementary conditions. By an asymptotic condition for the relevant fields, field equations and commutators of asymptotic fields are determined. A renormalization problem and an aspect concerning gauge transformations are also discussed. (auth.)

A new gauge for supersymmetric abelian gauge theories

International Nuclear Information System (INIS)

Smith, A.W.; Barcelos Neto, J.

1984-01-01

A new gauge for supersymmetric abelian gauge theories is presented. It is shown that this new gauge allows us to obtain terms which usually come as radiative corrections to the supersymmetric abelian gauge theories when one uses the Wess-Zumino gauge. (Author) [pt

World-sheet gauge fields in superstrings

International Nuclear Information System (INIS)

Porrati, M.; Tomboulis, E.T.

1989-01-01

We investigate the introduction of world-sheet 2-dimensional gauge fields in a manner consistent with world-sheet supersymmetry. We obtain the effective string action resulting from the exact integration over the world-sheet gauge fields to show that it generally describes string models with spontaneous breaking of gauge symmetries with continuous breaking parameters. We examine the question of spacetime supersymmetry spontaneous breaking, and show that breaking with continuous, in particular arbitrarily small breaking parameters does not occur; only breaking for discrete values of parameters is possible. (orig.)

Abelian gauge theories on homogeneous spaces

International Nuclear Information System (INIS)

Vassilevich, D.V.

1992-07-01

An algebraic technique of separation of gauge modes in Abelian gauge theories on homogeneous spaces is proposed. An effective potential for the Maxwell-Chern-Simons theory on S 3 is calculated. A generalization of the Chern-Simons action is suggested and analysed with the example of SU(3)/U(1) x U(1). (author). 11 refs

Are ghosts necessary in planar gauges?

International Nuclear Information System (INIS)

Kummer, W.

1988-01-01

The introduction of Faddeev-Popov ghosts in axial gauges and especially in the ones of the planar type is not a technical necessity for the general proof of renormalization and gauge independence. It is shown that all necessary identities for Green's functions and for one-particle-irreducible vertices arise in a completely ghost-free formulation as well

Continuum gauge fields from lattice gauge fields

International Nuclear Information System (INIS)

Goeckeler, M.; Kronfeld, A.S.; Schierholz, G.; Wiese, U.J.

1993-01-01

On the lattice some of the salient features of pure gauge theories and of gauge theories with fermions in complex representations of the gauge group seem to be lost. These features can be recovered by considering part of the theory in the continuum. The prerequisite for that is the construction of continuum gauge fields from lattice gauge fields. Such a construction, which is gauge covariant and complies with geometrical constructions of the topological charge on the lattice, is given in this paper. The procedure is explicitly carried out in the U(1) theory in two dimensions, where it leads to simple results. (orig.)

Lopsided Gauge Mediation

CERN Document Server

De Simone, Andrea; Giudice, Gian Francesco; Pappadopulo, Duccio; Rattazzi, Riccardo

2011-01-01

It has been recently pointed out that the unavoidable tuning among supersymmetric parameters required to raise the Higgs boson mass beyond its experimental limit opens up new avenues for dealing with the so called $\\mu$-$B_\\mu$ problem of gauge mediation. In fact, it allows for accommodating, with no further parameter tuning, large values of $B_\\mu$ and of the other Higgs-sector soft masses, as predicted in models where both $\\mu$ and $B_\\mu$ are generated at one-loop order. This class of models, called Lopsided Gauge Mediation, offers an interesting alternative to conventional gauge mediation and is characterized by a strikingly different phenomenology, with light higgsinos, very large Higgs pseudoscalar mass, and moderately light sleptons. We discuss general parametric relations involving the fine-tuning of the model and various observables such as the chargino mass and the value of $\\tan\\beta$. We build an explicit model and we study the constraints coming from LEP and Tevatron. We show that in spite of ne...

Gauging Variational Inference

Energy Technology Data Exchange (ETDEWEB)

Chertkov, Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ahn, Sungsoo [Korea Advanced Inst. Science and Technology (KAIST), Daejeon (Korea, Republic of); Shin, Jinwoo [Korea Advanced Inst. Science and Technology (KAIST), Daejeon (Korea, Republic of)

2017-05-25

Computing partition function is the most important statistical inference task arising in applications of Graphical Models (GM). Since it is computationally intractable, approximate methods have been used to resolve the issue in practice, where meanfield (MF) and belief propagation (BP) are arguably the most popular and successful approaches of a variational type. In this paper, we propose two new variational schemes, coined Gauged-MF (G-MF) and Gauged-BP (G-BP), improving MF and BP, respectively. Both provide lower bounds for the partition function by utilizing the so-called gauge transformation which modifies factors of GM while keeping the partition function invariant. Moreover, we prove that both G-MF and G-BP are exact for GMs with a single loop of a special structure, even though the bare MF and BP perform badly in this case. Our extensive experiments, on complete GMs of relatively small size and on large GM (up-to 300 variables) confirm that the newly proposed algorithms outperform and generalize MF and BP.

Neural multigrid for gauge theories and other disordered systems

International Nuclear Information System (INIS)

Baeker, M.; Kalkreuter, T.; Mack, G.; Speh, M.

1992-09-01

We present evidence that multigrid works for wave equations in disordered systems, e.g. in the presence of gauge fields, no matter how strong the disorder, but one needs to introduce a 'neural computations' point of view into large scale simulations: First, the system must learn how to do the simulations efficiently, then do the simulation (fast). The method can also be used to provide smooth interpolation kernels which are needed in multigrid Monte Carlo updates. (orig.)

Equations of motion according to the asymptotic post-Newtonian scheme for general relativity in the harmonic gauge

Science.gov (United States)

Arminjon, Mayeul

2005-10-01

The asymptotic scheme of post-Newtonian approximation defined for general relativity in the harmonic gauge by Futamase & Schutz (1983) is based on a family of initial data for the matter fields of a perfect fluid and for the initial metric, defining a family of weakly self-gravitating systems. We show that Weinberg’s (1972) expansion of the metric and his general expansion of the energy-momentum tensor T, as well as his expanded equations for the gravitational field and his general form of the expanded dynamical equations, apply naturally to this family. Then, following the asymptotic scheme, we derive the explicit form of the expansion of T for a perfect fluid, and the expanded fluid-dynamical equations. (These differ from those written by Weinberg.) By integrating these equations in the domain occupied by a body, we obtain a general form of the translational equations of motion for a 1PN perfect-fluid system in general relativity. To put them into a tractable form, we use an asymptotic framework for the separation parameter η, by defining a family of well-separated 1PN systems. We calculate all terms in the equations of motion up to the order η3 included. To calculate the 1PN correction part, we assume that the Newtonian motion of each body is a rigid one, and that the family is quasispherical, in the sense that in all bodies the inertia tensor comes close to being spherical as η→0. Apart from corrections that cancel for exact spherical symmetry, there is in the final equations of motion one additional term, as compared with the Lorentz-Droste (Einstein-Infeld-Hoffmann) acceleration. This term depends on the spin of the body and on its internal structure.

Digital lattice gauge theories

Science.gov (United States)

Zohar, Erez; Farace, Alessandro; Reznik, Benni; Cirac, J. Ignacio

2017-02-01

We propose a general scheme for a digital construction of lattice gauge theories with dynamical fermions. In this method, the four-body interactions arising in models with 2 +1 dimensions and higher are obtained stroboscopically, through a sequence of two-body interactions with ancillary degrees of freedom. This yields stronger interactions than the ones obtained through perturbative methods, as typically done in previous proposals, and removes an important bottleneck in the road towards experimental realizations. The scheme applies to generic gauge theories with Lie or finite symmetry groups, both Abelian and non-Abelian. As a concrete example, we present the construction of a digital quantum simulator for a Z3 lattice gauge theory with dynamical fermionic matter in 2 +1 dimensions, using ultracold atoms in optical lattices, involving three atomic species, representing the matter, gauge, and auxiliary degrees of freedom, that are separated in three different layers. By moving the ancilla atoms with a proper sequence of steps, we show how we can obtain the desired evolution in a clean, controlled way.

Two-dimensional nonlinear equations of supersymmetric gauge theories

International Nuclear Information System (INIS)

Savel'ev, M.V.

1985-01-01

Supersymmetric generalization of two-dimensional nonlinear dynamical equations of gauge theories is presented. The nontrivial dynamics of a physical system in the supersymmetry and supergravity theories for (2+2)-dimensions is described by the integrable embeddings of Vsub(2/2) superspace into the flat enveloping superspace Rsub(N/M), supplied with the structure of a Lie superalgebra. An equation is derived which describes a supersymmetric generalization of the two-dimensional Toda lattice. It contains both super-Liouville and Sinh-Gordon equations

RIKEN BNL RESEARCH CENTER WORKSHOP ON GAUGE-INVARIANT VARIABLES IN GAUGE THEORIES, VOLUME 20

Energy Technology Data Exchange (ETDEWEB)

VAN BAAL,P.; ORLAND,P.; PISARSKI,R.

2000-06-01

This four-day workshop focused on the wide variety of approaches to the non-perturbative physics of QCD. The main topic was the formulation of non-Abelian gauge theory in orbit space, but some other ideas were discussed, in particular the possible extension of the Maldacena conjecture to nonsupersymmetric gauge theories. The idea was to involve most of the participants in general discussions on the problem. Panel discussions were organized to further encourage debate and understanding. Most of the talks roughly fell into three categories: (1) Variational methods in field theory; (2) Anti-de Sitter space ideas; (3) The fundamental domain, gauge fixing, Gribov copies and topological objects (both in the continuum and on a lattice). In particular some remarkable progress in three-dimensional gauge theories was presented, from the analytic side by V.P. Nair and mostly from the numerical side by O. Philipsen. This work may ultimately have important implications for RHIC experiments on the high-temperature quark-gluon plasma.

Gauge field theory

International Nuclear Information System (INIS)

Aref'eva, I.Ya.; Slavnov, A.A.

1981-01-01

This lecture is devoted to the discussion of gauge field theory permitting from the single point of view to describe all the interactions of elementary particles. The authors used electrodynamics and the Einstein theory of gravity to search for a renormgroup fixing a form of Lagrangian. It is shown that the gauge invariance added with the requirement of the minimum number of arbitraries in Lagrangian fixes unambigously the form of the electromagnetic interaction. The generalization of this construction for more complicate charge spaces results in the Yang-Mills theory. The interaction form in this theory is fixed with the relativity principle in the charge space. A quantum scheme of the Yang-Mills fields through the explicit separation of true dynamic variables is suggested. A comfortable relativistically invariant diagram technique for the calculation of a producing potential for the Green functions is described. The Ward generalized identities have been obtained and a procedure of the elimination of ultraviolet and infrared divergencies has been accomplished. Within the framework of QCD (quantum-chromodynamic) the phenomenon of the asymptotic freedom being the most successful prediction of the gauge theory of strong interactions was described. Working methods with QCD outside the framework of the perturbation theory have been described from a coupling constant. QCD is represented as a single theory possessing both the asymptotical freedom and the freedom retaining quarks [ru

Absence of the Gribov ambiguity in a quadratic gauge

International Nuclear Information System (INIS)

Raval, Haresh

2016-01-01

The Gribov ambiguity exists in various gauges. Algebraic gauges are likely to be ambiguity free. However, algebraic gauges are not Lorentz invariant, which is their fundamental flaw. In addition, they are not generally compatible with the boundary conditions on the gauge fields, which are needed to compactify the space i.e., the ambiguity continues to exist on a compact manifold. Here we discuss a quadratic gauge fixing, which is Lorentz invariant. We consider an example of a spherically symmetric gauge field configuration in which we prove that this Lorentz invariant gauge removes the ambiguity on a compact manifold S 3 , when a proper boundary condition on the gauge configuration is taken into account. Thus, we provide one example where the ambiguity is absent on a compact manifold in the algebraic gauge. We also show that the BRST invariance is preserved in this gauge. (orig.)

Absence of the Gribov ambiguity in a quadratic gauge

Energy Technology Data Exchange (ETDEWEB)

Raval, Haresh [Indian Institute of Technology, Bombay, Department of Physics, Mumbai (India)

2016-05-15

The Gribov ambiguity exists in various gauges. Algebraic gauges are likely to be ambiguity free. However, algebraic gauges are not Lorentz invariant, which is their fundamental flaw. In addition, they are not generally compatible with the boundary conditions on the gauge fields, which are needed to compactify the space i.e., the ambiguity continues to exist on a compact manifold. Here we discuss a quadratic gauge fixing, which is Lorentz invariant. We consider an example of a spherically symmetric gauge field configuration in which we prove that this Lorentz invariant gauge removes the ambiguity on a compact manifold S{sup 3}, when a proper boundary condition on the gauge configuration is taken into account. Thus, we provide one example where the ambiguity is absent on a compact manifold in the algebraic gauge. We also show that the BRST invariance is preserved in this gauge. (orig.)

Renormalization scheme and gauge (in)dependence of the generalized Crewther relation: what are the real grounds of the β-factorization property?

Science.gov (United States)

Garkusha, A. V.; Kataev, A. L.; Molokoedov, V. S.

2018-02-01

The problem of scheme and gauge dependence of the factorization property of the renormalization group β-function in the SU( N c ) QCD generalized Crewther relation (GCR), which connects the flavor non-singlet contributions to the Adler and Bjorken polarized sum rule functions, is investigated at the O({a}_s^4) level of perturbation theory. It is known that in the gauge-invariant renormalization \\overline{MS} -scheme this property holds in the QCD GCR at least at this order. To study whether this factorization property is true in all gauge-invariant schemes, we consider the MS-like schemes in QCD and the QED-limit of the GCR in the \\overline{MS} -scheme and in two other gauge-independent subtraction schemes, namely in the momentum MOM and the on-shell OS schemes. In these schemes we confirm the existence of the β-function factorization in the QCD and QED variants of the GCR. The problem of the possible β-factorization in the gauge-dependent renormalization schemes in QCD is studied. To investigate this problem we consider the gauge non-invariant mMOM and MOMgggg-schemes. We demonstrate that in the mMOM scheme at the O({a}_s^3) level the β-factorization is valid for three values of the gauge parameter ξ only, namely for ξ = -3 , -1 and ξ = 0. In the O({a}_s^4) order of PT it remains valid only for case of the Landau gauge ξ = 0. The consideration of these two gauge-dependent schemes for the QCD GCR allows us to conclude that the factorization of RG β-function will always be implemented in any MOM-like renormalization schemes with linear covariant gauge at ξ = 0 and ξ = -3 at the O({a}_s^3) approximation. It is demonstrated that if factorization property for the MS-like schemes is true in all orders of PT, as theoretically indicated in the several works on the subject, then the factorization will also occur in the arbitrary MOM-like scheme in the Landau gauge in all orders of perturbation theory as well.

Gauged supergravities in various spacetime dimensions

Energy Technology Data Exchange (ETDEWEB)

Weidner, M.

2006-12-15

In this thesis we study the gaugings of extended supergravity theories in various space-time dimensions. These theories describe the low-energy limit of non-trivial string compactifications. For each theory under consideration we work out all possible gaugings that are compatible with supersymmetry. They are parameterized by the so-called embedding tensor which is a group theoretical object that has to satisfy certain representation constraints. This embedding tensor determines all couplings in the gauged theory that are necessary to preserve gauge invariance and supersymmetry. The concept of the embedding tensor and the general structure of the gauged supergravities are explained in detail. The methods are then applied to the half-maximal (N=4) supergravities in d=4 and d=5 and to the maximal supergravities in d=2 and d=7. Examples of particular gaugings are given. Whenever possible, the higher-dimensional origin of these theories is identified and it is shown how the compactification parameters like fluxes and torsion are contained in the embedding tensor. (orig.)

Radioisotope Gauges

International Nuclear Information System (INIS)

Tominaga, Hiroshi

1980-01-01

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.)

Gauge systems and functions, hermitian operators and clocks as conjugate functions for the constraints

International Nuclear Information System (INIS)

Cuesta, Vladimir; Vergara, Jose David; Montesinos, Merced

2011-01-01

We work with gauge systems and using gauge invariant functions we study its quantum counterpart and we find if all these operators are self adjoint or not. Our study is divided in two cases, when we choose clock or clocks that its Poisson brackets with the set of constraints is one or it is different to one. We show some transition amplitudes.

Dynamic linearization system for a radiation gauge

International Nuclear Information System (INIS)

Panarello, J.A.

1977-01-01

The linearization system and process converts a high resolution non-linear analog input signal, representative of the thickness of an object, into a high resolution linear analog output signal suitable for use in driving a variety of output devices. The system requires only a small amount of memory for storing pre-calculated non-linear correction coefficients. The system channels the input signal to separate circuit paths so that it may be used directly to; locate an appropriate correction coefficient; develop a correction term after an appropriate correction coefficient is located; and develop a linearized signal having the same high resolution inherent in the input signal. The system processes the linearized signal to compensate for the possible errors introduced by radiation source noise. The processed linearized signal is the high resolution linear analog output signal which accurately represents the thickness of the object being gauged

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

International Nuclear Information System (INIS)

Suzuki, H.

1991-01-01

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

Non(anti)commutative gauge theories in harmonic superspace

International Nuclear Information System (INIS)

Quevedo Z., L.E.

2006-01-01

In this work we study the properties of non-singlet Q-deformed N=2 supersymmetric gauge theories, from a field-theoretical point of view. Starting from the supersymmetry breaking pattern induced by a general deformation matrix, we embark on the construction of the non-singlet deformed gauge transformation laws for all vector multiplet fields and their corresponding minimal Seiberg-Witten map. Several deformes super-Yang-Mills actions in components corresponding to different choices of the non-singlet deformation tensor are built. For a particular decomposition ansats of such tensor, we obtain exact actions describing the bosonic sector of the deformed N=(1,0) and the full action for enhances N=(1,1/2) residual supersymmetry. A tuned supersymmetry breaking of this enhanced action down to the N=(1,0) case is found by weakly restoring some discarded degrees of freedom of the deformation. Finally we find the associated residual supersymmetry transformations for the cases studied. The first part of this work, gives an overview of noncommutativity in quantum field theory and of harmonic superspace as needed to define noncommutative generalizations of extended gauge field theories. A study of general properties of non(anti)commutative structures in N=2 euclidean superspace and the (super)symmetry breaking pattern induced by Q-deformations follows. in addition, singlet-deformed super-Yang-Mills is given as an example. The second part deals with non-singlet Q-deformations of gauge theories. We introduce a decomposition ansatz for the deformation matrix, allowing an exact study of the deformed gauge transformations, and develop a general algorithm to solve the harmonic equations associated to this decomposition. A close expression for the gauge transformations of component fields is derived, along with the corresponding minimal Seiberg-Witten map to an equivalent commutative gauge theory. Finally we build deformed super-Yang-Mills actions and their corresponding

Non-Abelian gauge field theory in scale relativity

International Nuclear Information System (INIS)

Nottale, Laurent; Celerier, Marie-Noeelle; Lehner, Thierry

2006-01-01

Gauge field theory is developed in the framework of scale relativity. In this theory, space-time is described as a nondifferentiable continuum, which implies it is fractal, i.e., explicitly dependent on internal scale variables. Owing to the principle of relativity that has been extended to scales, these scale variables can themselves become functions of the space-time coordinates. Therefore, a coupling is expected between displacements in the fractal space-time and the transformations of these scale variables. In previous works, an Abelian gauge theory (electromagnetism) has been derived as a consequence of this coupling for global dilations and/or contractions. We consider here more general transformations of the scale variables by taking into account separate dilations for each of them, which yield non-Abelian gauge theories. We identify these transformations with the usual gauge transformations. The gauge fields naturally appear as a new geometric contribution to the total variation of the action involving these scale variables, while the gauge charges emerge as the generators of the scale transformation group. A generalized action is identified with the scale-relativistic invariant. The gauge charges are the conservative quantities, conjugates of the scale variables through the action, which find their origin in the symmetries of the ''scale-space.'' We thus found in a geometric way and recover the expression for the covariant derivative of gauge theory. Adding the requirement that under the scale transformations the fermion multiplets and the boson fields transform such that the derived Lagrangian remains invariant, we obtain gauge theories as a consequence of scale symmetries issued from a geometric space-time description

Antisymmetric tensor Zp gauge symmetries in field theory and string theory

International Nuclear Information System (INIS)

Berasaluce-González, Mikel; Ramírez, Guillermo; Uranga, Angel M.

2014-01-01

We consider discrete gauge symmetries in D dimensions arising as remnants of broken continuous gauge symmetries carried by general antisymmetric tensor fields, rather than by standard 1-forms. The lagrangian for such a general Z p gauge theory can be described in terms of a r-form gauge field made massive by a (r−1)-form, or other dual realizations, that we also discuss. The theory contains charged topological defects of different dimensionalities, generalizing the familiar charged particles and strings in D=4. We describe realizations in string theory compactifications with torsion cycles, or with background field strength fluxes. We also provide examples of non-abelian discrete groups, for which the group elements are associated with charged objects of different dimensionality

The "Forgotten" Pseudomomenta and Gauge Changes in Generalized Landau Level Problems: Spatially Nonuniform Magnetic and Temporally Varying Electric Fields

Science.gov (United States)

Konstantinou, Georgios; Moulopoulos, Konstantinos

2017-05-01

By perceiving gauge invariance as an analytical tool in order to get insight into the states of the "generalized Landau problem" (a charged quantum particle moving inside a magnetic, and possibly electric field), and motivated by an early article that correctly warns against a naive use of gauge transformation procedures in the usual Landau problem (i.e. with the magnetic field being static and uniform), we first show how to bypass the complications pointed out in that article by solving the problem in full generality through gauge transformation techniques in a more appropriate manner. Our solution provides in simple and closed analytical forms all Landau Level-wavefunctions without the need to specify a particular vector potential. This we do by proper handling of the so-called pseudomomentum ěc {{K}} (or of a quantity that we term pseudo-angular momentum L z ), a method that is crucially different from the old warning argument, but also from standard treatments in textbooks and in research literature (where the usual Landau-wavefunctions are employed - labeled with canonical momenta quantum numbers). Most importantly, we go further by showing that a similar procedure can be followed in the more difficult case of spatially-nonuniform magnetic fields: in such case we define ěc {{K}} and L z as plausible generalizations of the previous ordinary case, namely as appropriate line integrals of the inhomogeneous magnetic field - our method providing closed analytical expressions for all stationary state wavefunctions in an easy manner and in a broad set of geometries and gauges. It can thus be viewed as complementary to the few existing works on inhomogeneous magnetic fields, that have so far mostly focused on determining the energy eigenvalues rather than the corresponding eigenkets (on which they have claimed that, even in the simplest cases, it is not possible to obtain in closed form the associated wavefunctions). The analytical forms derived here for these

Pressure gauge experiments in India

Digital Repository Service at National Institute of Oceanography (India)

Joseph, A; Desa, E.; VijayKumar, K.; Desa, E.S.; Desai, R.G.P.; Prabhudesai, S.

. The effective mean density directly estimated by the use of a dual pressure gauge system was in close agreement with the density of water samples measured using a precision densitometer. Good quality sea level measurements can be obtained from pressure gauges...

Local gauge invariant Lagrangeans in classical field theories

International Nuclear Information System (INIS)

Grigore, D.R.

1982-07-01

We investigate the most general local gauge invariant Lagrangean in the framework of classical field theory. We rederive esentially Utiyama's result with a slight generalization. Our proof makes clear the importance of the so called current conditions, i.e. the requirement that the Noether currents are different from zero. This condition is of importance both in the general motivation for the introduction of the Yang-Mills fields and for the actual proof. Some comments are made about the basic mathematical structure of the problem - the gauge group. (author)

An introduction to gauge theories

CERN Document Server

Cabibbo, Nicola; Benhar, Omar

2017-01-01

Written by three of the world's leading experts on particle physics and the standard model, including an award-winning former director general of CERN, this book provides a completely up-to-date account of gauge theories. Starting from Feynman’s path integrals, Feynman rules are derived, gauge fixing and Faddeev-Popov ghosts are discussed, and renormalization group equations are derived. Several important applications to quantum electrodynamics and quantum chromodynamics (QCD) are discussed, including the one-loop derivation of asymptotic freedom for QCD.

Lattice calculations in gauge theory

International Nuclear Information System (INIS)

Rebbi, C.

1985-01-01

The lattice formulation of quantum gauge theories is discussed as a viable technique for quantitative studies of nonperturbative effects in QCD. Evidence is presented to ascertain that whole classes of lattice actions produce a universal continuum limit. Discrepancies between numerical results from Monto Carlo simulations for the pure gauge system and for the system with gauge and quark fields are discussed. Numerical calculations for QCD require very substantial computational resources. The use of powerful vector processors of special purpose machines, in extending the scope and magnitude or the calculations is considered, and one may reasonably expect that in the near future good quantitative predictions will be obtained for QCD

Coulomb branches for rank 2 gauge groups in 3dN=4 gauge theories

Energy Technology Data Exchange (ETDEWEB)

Hanany, Amihay [Theoretical Physics Group, Imperial College London,Prince Consort Road, London, SW7 2AZ (United Kingdom); Sperling, Marcus [Institut für Theoretische Physik, Leibniz Universität Hannover,Appelstraße 2, 30167 Hannover (Germany)

2016-08-02

The Coulomb branch of 3-dimensional N=4 gauge theories is the space of bare and dressed BPS monopole operators. We utilise the conformal dimension to define a fan which, upon intersection with the weight lattice of a GNO-dual group, gives rise to a collection of semi-groups. It turns out that the unique Hilbert bases of these semi-groups are a sufficient, finite set of monopole operators which generate the entire chiral ring. Moreover, the knowledge of the properties of the minimal generators is enough to compute the Hilbert series explicitly. The techniques of this paper allow an efficient evaluation of the Hilbert series for general rank gauge groups. As an application, we provide various examples for all rank two gauge groups to demonstrate the novel interpretation.

Nonlinear sigma-models and their gauging in and out of superspace

International Nuclear Information System (INIS)

Hull, C.M.; California Univ., Santa Barbara; Karlhede, A.; Lindstroem, U.; Rocek, M.

1986-01-01

We analyze and generalize bosonic nonlinear sigma-models and their N=1,2 supersymmetric extensions in (4 spacetime-dimensional) N=1 superspace. We give a general construction of nonminimal kinetic terms for gauge fields and of N=1,2 gauging of isometries on Kaehler and hyper-Kaehler manifolds. In particular, we study the gauging of noncompact groups. We derive the complete component action and supertrace formula. For N=2 models, the supertrace always vanishes. (orig.)

Gauge invariant definition of the jet quenching parameter

International Nuclear Information System (INIS)

Benzke, Michael

2013-01-01

We use the framework of Glauber extended Soft-Collinear Effective Theory to explicitly derive a gauge invariant expression of the jet quenching parameter q -hat . The effective theory approach offers a systematic power counting scheme at the Lagrangian level and allows for a consistent treatment of the relevant scales in the problem. Employing this approach in a covariant gauge scenario lead to an expression for q -hat containing the expectation value of two light-cone Wilson lines. We find that in a general gauge, additional interaction terms in the Lagrangian have to be considered, leading to the introduction of transverse gauge links

Renormalization of composite operators in Yang-Mills theories using a general covariant gauge

International Nuclear Information System (INIS)

Collins, J.C.; Scalise, R.J.

1994-01-01

Essential to QCD applications of the operator product expansion, etc., is a knowledge of those operators that mix with gauge-invariant operators. A standard theorem asserts that the renormalization matrix is triangular: Gauge-invariant operators have ''alien'' gauge-variant operators among their counterterms, but, with a suitably chosen basis, the necessary alien operators have only themselves as counterterms. Moreover, the alien operators are supposed to vanish in physical matrix elements. A recent calculation by Hamberg and van Neerven apparently contradicts these results. By explicit calculations with the energy-momentum tensor, we show that the problems arise because of subtle infrared singularities that appear when gluonic matrix elements are taken on shell at zero momentum transfer

The gauge-independent QCD effective charge

International Nuclear Information System (INIS)

Watson, N.J.

1997-01-01

It is shown how the QED concept of a gauge-, scale- and scheme-independent one-loop effective charge can be extended directly at the diagrammatic level to QCD, thus justifying explicitly the ''naive non-abelianization'' prescription used in renormalon calculus. It is first argued that, for on-shell external fields and at the strictly one-loop level, the required gluon self-energy-like function is precisely that obtained from S-matrix elements via the pinch technique. The generalization of the pinch technique to explicitly off-shell processes is then introduced. It is shown how, as a result of a fundamental cancellation among conventional perturbation theory diagrams, encoded in the QCD Ward identities, the pinch technique one-loop gluon self-energy iΠ μν ab (q) remains gauge-independent and universal regardless of the fact that the ''external'' fields in the given process are off-shell. This demonstration involves a simple technique enabling the isolation, in an arbitrary gauge, of iΠ μν ab (q) from subclasses of up to several hundred diagrams at once. Furthermore, it is shown how this one-loop cancellation mechanism iterates for the subclasses of n-loop diagrams containing implicitly the Dyson chains of n one-loop self-energies iΠ μν ab (q). The gauge cancellation required for the Dyson summation of iΠ μν ab (q) is thus demonstrated explicitly in a general class of ghost-free gauges for all orders n. (orig.)

Gauge choice in Witten's energy expression

International Nuclear Information System (INIS)

Parker, T.H.

1985-01-01

Witten's equation Dpsi=0 can be interpreted as a gauge fixing condition for classical supergravity. We rigorously prove the existence of asymptotically constant solutions of the more general gauge condition Dpsi=Apsi for almost all endomorphisms A of the spin bundle. Each gives an expression for the gravitational energy similar to Witten's. These include the choice A=√R, which yields the particularly elegant energy expression first noticed by Deser. (orig.)

Nonabelian noncommutative gauge theory via noncommutative extra dimensions

Energy Technology Data Exchange (ETDEWEB)

Jurco, Branislav E-mail: jurco@theorie.physik.uni-muenchen.de; Schupp, Peter E-mail: schupp@theorie.physik.uni-muenchen.de; Wess, Julius E-mail: wess@theorie.physik.uni-muenchen.de

2001-06-18

The concept of covariant coordinates on noncommutative spaces leads directly to gauge theories with generalized noncommutative gauge fields of the type that arises in string theory with background B-fields. The theory is naturally expressed in terms of cochains in an appropriate cohomology; we discuss how it fits into the framework of projective modules. The equivalence of star products that arise from the background field with and without fluctuations and Kontsevich's formality theorem allow an explicitly construction of a map that relates ordinary gauge theory and noncommutative gauge theory (Seiberg-Witten map). As application we show the exact equality of the Dirac-Born-Infeld action with B-field in the commutative setting and its semi-noncommutative cousin in the intermediate picture. Using noncommutative extra dimensions the construction is extended to noncommutative nonabelian gauge theory for arbitrary gauge groups; an explicit map between abelian and nonabelian gauge fields is given. All constructions are also valid for non-constant B-field, Poisson structure and metric.

Nonabelian noncommutative gauge theory via noncommutative extra dimensions

International Nuclear Information System (INIS)

Jurco, Branislav; Schupp, Peter; Wess, Julius

2001-01-01

The concept of covariant coordinates on noncommutative spaces leads directly to gauge theories with generalized noncommutative gauge fields of the type that arises in string theory with background B-fields. The theory is naturally expressed in terms of cochains in an appropriate cohomology; we discuss how it fits into the framework of projective modules. The equivalence of star products that arise from the background field with and without fluctuations and Kontsevich's formality theorem allow an explicitly construction of a map that relates ordinary gauge theory and noncommutative gauge theory (Seiberg-Witten map). As application we show the exact equality of the Dirac-Born-Infeld action with B-field in the commutative setting and its semi-noncommutative cousin in the intermediate picture. Using noncommutative extra dimensions the construction is extended to noncommutative nonabelian gauge theory for arbitrary gauge groups; an explicit map between abelian and nonabelian gauge fields is given. All constructions are also valid for non-constant B-field, Poisson structure and metric

Linear supermultiplets and non-holomorphic gauge coupling functions

International Nuclear Information System (INIS)

Binetruy, P.; Grimm, R.; Girardi, G.

1991-04-01

The general couplings of linear multiplets, including Chern-Simons forms, to chiral matter as well as to the standard supergravity-matter system are constructed. Insisting on a canonically normalised Einstein term in particular the appearance of non-holomorphic gauge couplings are discussed and duality transformations in full generality are performed. The implications of these structures for the effective description of sigma model anomalies are presented with and without coupling to supergravity, following recent proposals of Derendinger, Ferrara, Kounnas and Zwirner and of Cardoso and Ovrut. (author) 14 refs

ENRAF Series 854 Advanced Technology Gauge (ATG) Acceptance Test Procedure

International Nuclear Information System (INIS)

HUBER, J.H.

1999-01-01

This procedure provides acceptance testing for Enraf Series 854 level gauges used to monitor levels in Hanford Waste Storage Tanks. The test will verify that the gauge functions according to the manufacturer's instructions and specifications and is properly setup prior to being delivered to the tank farm area. This ATP does not set up the gauge for any specific tank, but is generalized to permit testing the gauge prior to installation package preparation

On the gauge dependence of vacuum transitions at finite temperature

Energy Technology Data Exchange (ETDEWEB)

Garny, Mathias [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Konstandin, Thomas [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); European Organization for Nuclear Research (CERN), Geneva (Switzerland)

2012-05-15

In principle, observables as for example the sphaleron rate or the tunneling rate in a first-order phase transition are gauge-independent. However, in practice a gauge dependence is introduced in explicit perturbative calculations due to the breakdown of the gradient expansion of the effective action in the symmetric phase. We exemplify the situation using the effective potential of the Abelian Higgs model in the general renormalizable gauge. Still, we find that the quantitative dependence on the gauge choice is small for gauges that are consistent with the perturbative expansion.

Gauge equivalence between two-boson KP hierarchies

International Nuclear Information System (INIS)

Aratyn, H.

1994-01-01

In this paper it is explained the status of the two-boson KP hierarchy, which appears in this setting as an invariant subspace of the coadjoint orbit within the KP l=1 hierarchy. We will work with two main cases of two-boson KP hierarchies, one defined within KP l=1 hierarchy will be called Faa di Bruno KP hierarchy, while the second defined within KP hierarchy for a quadratic two-boson KP hierarchy. It will be established for them the gauge invariance playing the role of generalized Miura transformations. It is emphasized the symplectic character of equivalence of KP l=1 and KP. It is also made a point that the gauge equivalence established for two-boson systems is valid for an arbitrary n-th Poisson bracket structure and not only the first Poisson bracket structure. (author). 7 refs

On the structure of translational gauge theories of gravitation

International Nuclear Information System (INIS)

Wallner, R.P.

1982-01-01

Guided by decoupling processes in general gauge theories, we examine the translation limit in U 4 -theories. It is shown that this leads to Einstein's gravity theory as the appropriate choice for a translational gauge theory of gravitation. (Author)

The extended local gauge invariance and the BRS symmetry in stochastic quantization of gauge fields

International Nuclear Information System (INIS)

Nakazawa, Naohito.

1989-05-01

We investigate the BRS invariance of the first-class constrained systems in the context of the stochastic quantization. For the first-class constrained systems, we construct the nilpotent BRS transformation and the BRS invariant stochastic effective action based on the D+1 dimensional field theoretical formulation of stochastic quantization. By eliminating the multiplier field of the gauge fixing condition and an auxiliary field, it is shown that there exists a truncated BRS transformation which satisfies the nilpotency condition. The truncated BRS invariant stochastic action is also derived. As the examples of the general formulation, we investigate the BRS invariant structure in the massless and massive Yang-Mills fields in stochastic quantization. (author)

Hamiltonian Noether theorem for gauge systems and two time physics

International Nuclear Information System (INIS)

Villanueva, V M; Nieto, J A; Ruiz, L; Silvas, J

2005-01-01

The Noether theorem for Hamiltonian constrained systems is revisited. In particular, our review presents a novel method to show that the gauge transformations are generated by the conserved quantities associated with the first class constraints. We apply our results to the relativistic point particle, to the Friedberg et al model and, with special emphasis, to two time physics

Light-cone gauge versus proper-time gauge for massless spinning particles

International Nuclear Information System (INIS)

Skagerstam, B.S.; Stern, A.

1987-01-01

Although the light-cone gauge is convenient for many applications in physics, it is known to distort topology. We show that as a consequence, some interesting, possibly physical, features of a quantum theory may be missed when working in the light-cone gauge. We shall illustrate this by examining the description of massless spinning particles in an arbitrary number of space-time dimensions. When quantizing such particles in four space-time dimensions (without introducing Grassmann degrees of freedom), the light-cone gauge yields a purely bosonic spectrum, i.e. the helicity λ is integer-valued. The problem is rectified by going to the proper-time gauge; there λ = 0, ±1/2, ±1, ... Upon using the proper-time gauge to quantize massless particle systems in more than four space-time dimensions, we find the following interesting features: Except for space-time dimension d equal to 5 and 9, (i) wave functions cannot be expressed as global functions of momentum (or position). (This is also true for d=4.) Further, for d ≠ 5 and 9, (ii) the helicity group spin (d-2) and (iii) canonical position operators do not exist, globally. (The result that helicity cannot be globally defined resembles a known property of nonabelian monopoles arising in grand unified theories. There, topological obstructions prevent one from defining the color group, globally.) All of the features (i)-(iii) are missed when working in the light-cone gauge. (orig.)

Perturbative unitarity constraints on gauge portals

Science.gov (United States)

El Hedri, Sonia; Shepherd, William; Walker, Devin G. E.

2017-12-01

Dark matter that was once in thermal equilibrium with the Standard Model is generally prohibited from obtaining all of its mass from the electroweak phase transition. This implies a new scale of physics and mediator particles to facilitate dark matter annihilation. In this work, we focus on dark matter that annihilates through a generic gauge boson portal. We show how partial wave unitarity places upper bounds on the dark gauge boson, dark Higgs and dark matter masses. Outside of well-defined fine-tuned regions, we find an upper bound of 9 TeV for the dark matter mass when the dark Higgs and dark gauge bosons both facilitate the dark matter annihilations. In this scenario, the upper bound on the dark Higgs and dark gauge boson masses are 10 TeV and 16 TeV, respectively. When only the dark gauge boson facilitates dark matter annihilations, we find an upper bound of 3 TeV and 6 TeV for the dark matter and dark gauge boson, respectively. Overall, using the gauge portal as a template, we describe a method to not only place upper bounds on the dark matter mass but also on the new particles with Standard Model quantum numbers. We briefly discuss the reach of future accelerator, direct and indirect detection experiments for this class of models.

Duality transformations for general abelian systems

International Nuclear Information System (INIS)

Savit, R.

1982-01-01

We describe the general structure of duality transformations for a very broad set of abelian statistical and field theoretic systems. This includes theories with many different types of fields and a large variety of kinds of interactions including, but not limited to nearest neighbor, next nearest neighbor, multi-spin interactions, etc. We find that the dual form of a theory does not depend directly on the dimensionality of the theory, but rather on the number of fields and number of different kinds of interactions. The dual forms we find have a generalized gauge symmetry and posses the usual property of having a temperature (or coupling constant) which is inverted from that of the original theory. Our results reduce to the well-known results in those particular cases that have heretofore been studied. Our procedure also suggests variations capable of generating other forms of the dual theory which may be useful in various specific cases. (orig.)

Once more about the topologically massive gauge theory

International Nuclear Information System (INIS)

Kogan, Ya.I.

1989-01-01

The general properties of the three-dimensional gauge theory with the topological mass is discussed namely the long-range interaction of the Aharonov-Bohm type. It is argued that Chern-Simons gauge theories must be considered as the infrared limit of the topologically massive theories. The analogy between the Landau problem of a charged particle in a magnetic field and quantization of this gauge theory is considered, as well as the quantization condition for the Abelian Chern-Simons term. 38 refs.; 5 figs

Non-abelian gauge invariant classical Lagrangian formalism for point electric and magnetic charge

International Nuclear Information System (INIS)

Brandt, R.A.; Neri, F.

1978-01-01

The classical electrodynamics of electrically charged point particles has been generalized to include non-Abelian gauge groups and to include magnetically charged point particles. In this paper these two distinct generalizations are unified into a non-Abelian gauge theory of electric and magnetic charge. Just as the electrically charged particles constitute the generalized source of the gauge fields, the magnetically charged particles constitute the generalized source of the dual fields. The resultant equations of motion are invariant to the original 'electric' non-Abelian gauge group, but, because of the absence of a corresponding 'magnetic' gauge group, there is no 'duality' symmetry between electric and magnetic quantities. However, for a class of solutions to these equations, which includes all known point electric and magnetic monopole constructions, there is shown to exist an equivalent description based on a magnetic, rather than electric, gauge group. The gauge potentials in general are singular on strings extending from the particle position to infinity, but it is shown that the observables are without string singularities, and that the theory is Lorentz invariant, provided a charge quantization condition is satisfied. This condition, deduced from a stability analysis, is necessary for the consistency of the classical non-Abelian theory, in contrast to the Abelian case, where such a condition is necessary only for the consistency of the quantum theory. It is also shown that in the classical theory the strings cannot be removed by gauge transformations, as they sometimes can be in the quantum theory. (Auth.)

Machines for lattice gauge theory

International Nuclear Information System (INIS)

Mackenzie, P.B.

1989-05-01

The most promising approach to the solution of the theory of strong interactions is large scale numerical simulation using the techniques of lattice gauge theory. At the present time, computing requirements for convincing calculations of the properties of hadrons exceed the capabilities of even the most powerful commercial supercomputers. This has led to the development of massively parallel computers dedicated to lattice gauge theory. This talk will discuss the computing requirements behind these machines, and general features of the components and architectures of the half dozen major projects now in existence. 20 refs., 1 fig

An expert system for the conception of industrial gauges based on beta, gamma or X ray transmission (JANU)

International Nuclear Information System (INIS)

Tola, F.

2000-01-01

A knowledge based software (named JANU expert system) for radiogauges design mainly density, thickness, mass per unit area, level and two-phase flows gauges, was prepared recently. Its aim is to optimise the different components of a transmission gauge (radioactive source, detector, electronic device, collimators and shielding), taking into account parameters and constraints linked to the configuration (nature and composition of materials, presence of shields and walls, ...), as well as users requirements (accuracy, counting time, beam collimating, duration of tests, ...). The database includes characteristics of radionuclides and industrial sources, photon cross sections, build-up factors, specific dose constants, physical properties of elements, usual scintillation detectors and shielding materials. It allows the determination of the most suited emitter, as well as a precise characterisation of a given emitter, including required source activity, expected counting rates, dose rates, etc. It has been extended to X rays generators, voltage and current intensity replacing in this case the energy and activity of the source. Information supplied by JANU has been validated by applications developed during the past 30 years. Its choices have always revealed most judicious and in general, numerical results in good agreement with experiments. Thus, it has become an essential and reliable tool for gauge designers. (author)

Perturbative Quantum Gravity from Gauge Theory

Science.gov (United States)

Carrasco, John Joseph

In this dissertation we present the graphical techniques recently developed in the construction of multi-loop scattering amplitudes using the method of generalized unitarity. We construct the three-loop and four-loop four-point amplitudes of N = 8 supergravity using these methods and the Kawaii, Lewellen and Tye tree-level relations which map tree-level gauge theory amplitudes to tree-level gravity theory amplitudes. We conclude by extending a tree-level duality between color and kinematics, generic to gauge theories, to a loop level conjecture, allowing the easy relation between loop-level gauge and gravity kinematics. We provide non-trivial evidence for this conjecture at three-loops in the particular case of maximal supersymmetry.

Precision contact level gauge

International Nuclear Information System (INIS)

Krejci, M.; Pilat, M.; Stulik, P.

1977-01-01

Equipment was developed measuring the heavy water level in the TR-0 reactor core within an accuracy of several hundredths of a millimeter in a range of around 3.5 m and at a temperature of up to 90 degC. The equipment uses a vibrating needle contact as a high sensitivity level gauge and a servomechanical system with a motion screw carrying the gauge for monitoring and measuring the level in the desired range. The advantage of the unique level gauge consists in that that the transducer converts the measured level position to an electric signal, ie., pulse width, with high sensitivity and without hysteresis. (Kr)

Nonequilibrium formulation of abelian gauge theories

Energy Technology Data Exchange (ETDEWEB)

Zoeller, Thorsten

2013-09-01

This work is about a formulation of abelian gauge theories out-of-equilibrium. In contrast to thermal equilibrium, systems out-of-equilibrium are not constant in time, and the interesting questions in such systems refer to time evolution problems. After a short introduction to quantum electrodynamics (QED), the two-particle irreducible (2PI) effective action is introduced as an essential technique for the study of quantum field theories out-of-equilibrium. The equations of motion (EOMs) for the propagators of the theory are then derived from it. It follows a discussion of the physical degrees of freedom (DOFs) of the theory, in particular with respect to the photons, since in covariant formulations of gauge theories unphysical DOFs are necessarily contained. After that the EOMs for the photon propagator are examined more closely. It turns out that they are structurally complicated, and a reformulation of the equations is presented which for the untruncated theory leads to an essential structural simplification of the EOMs. After providing the initial conditions which are necessary in order to solve the EOMs, the free photon EOMs are solved with the help of the reformulated equations. It turns out that the solutions diverge in time, i.e. they are secular. This is a manifestation of the fact that gauge theories contain unphysical DOFs. It is reasoned that these secularities exist only in the free case and are therefore ''artificial''. It is however emphasized that they may not be a problem in principle, but certainly are in practice, in particular for the numerical solution of the EOMs. Further, the origin of the secularities, for which there exists an illustrative explanation, is discussed in more detail. Another characteristic feature of 2PI formulations of gauge theories is the fact that quantities calculated from approximations of the 2PI effective action, which are gauge invariant in the exact theory as well as in an approximated theory at

Linear bosonic and fermionic quantum gauge theories on curved spacetimes

International Nuclear Information System (INIS)

Hack, Thomas-Paul; Schenkel, Alexander

2012-05-01

We develop a general setting for the quantization of linear bosonic and fermionic field theories subject to local gauge invariance and show how standard examples such as linearized Yang-Mills theory and linearized general relativity fit into this framework. Our construction always leads to a well-defined and gauge-invariant quantum field algebra, the centre and representations of this algebra, however, have to be analysed on a case-by-case basis. We discuss an example of a fermionic gauge field theory where the necessary conditions for the existence of Hilbert space representations are not met on any spacetime. On the other hand, we prove that these conditions are met for the Rarita-Schwinger gauge field in linearized pure N=1 supergravity on certain spacetimes, including asymptotically flat spacetimes and classes of spacetimes with compact Cauchy surfaces. We also present an explicit example of a supergravity background on which the Rarita-Schwinger gauge field can not be consistently quantized.

Linear bosonic and fermionic quantum gauge theories on curved spacetimes

Energy Technology Data Exchange (ETDEWEB)

Hack, Thomas-Paul [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Schenkel, Alexander [Bergische Univ., Wuppertal (Germany). Fachgruppe Physik

2012-05-15

We develop a general setting for the quantization of linear bosonic and fermionic field theories subject to local gauge invariance and show how standard examples such as linearized Yang-Mills theory and linearized general relativity fit into this framework. Our construction always leads to a well-defined and gauge-invariant quantum field algebra, the centre and representations of this algebra, however, have to be analysed on a case-by-case basis. We discuss an example of a fermionic gauge field theory where the necessary conditions for the existence of Hilbert space representations are not met on any spacetime. On the other hand, we prove that these conditions are met for the Rarita-Schwinger gauge field in linearized pure N=1 supergravity on certain spacetimes, including asymptotically flat spacetimes and classes of spacetimes with compact Cauchy surfaces. We also present an explicit example of a supergravity background on which the Rarita-Schwinger gauge field can not be consistently quantized.

Weakly Isolated horizons: first order actions and gauge symmetries

Science.gov (United States)

Corichi, Alejandro; Reyes, Juan D.; Vukašinac, Tatjana

2017-04-01

The notion of Isolated Horizons has played an important role in gravitational physics, being useful from the characterization of the endpoint of black hole mergers to (quantum) black hole entropy. With an eye towards a canonical formulation we consider general relativity in terms of connection and vierbein variables and their corresponding first order actions. We focus on two main issues: (i) The role of the internal gauge freedom that exists, in the consistent formulations of the action principle, and (ii) the role that a 3  +  1 canonical decomposition has in the allowed internal gauge freedom. More concretely, we clarify in detail how the requirement of having well posed variational principles compatible with general weakly isolated horizons (WIHs) as internal boundaries does lead to a partial gauge fixing in the first order descriptions used previously in the literature. We consider the standard Hilbert-Palatini action together with the Holst extension (needed for a consistent 3  +  1 decomposition), with and without boundary terms at the horizon. We show in detail that, for the complete configuration space—with no gauge fixing—, while the Palatini action is differentiable without additional surface terms at the inner WIH boundary, the more general Holst action is not. The introduction of a surface term at the horizon—that renders the action for asymptotically flat configurations differentiable—does make the Holst action differentiable, but only if one restricts the configuration space and partially reduces the internal Lorentz gauge. For the second issue at hand, we show that upon performing a 3  +  1 decomposition and imposing the time gauge, there is a further gauge reduction of the Hamiltonian theory in terms of Ashtekar-Barbero variables to a U(1)-gauge theory on the horizon. We also extend our analysis to the more restricted boundary conditions of (strongly) isolated horizons as inner boundary. We show that even when the

Weakly Isolated horizons: first order actions and gauge symmetries

International Nuclear Information System (INIS)

Corichi, Alejandro; Reyes, Juan D; Vukašinac, Tatjana

2017-01-01

The notion of Isolated Horizons has played an important role in gravitational physics, being useful from the characterization of the endpoint of black hole mergers to (quantum) black hole entropy. With an eye towards a canonical formulation we consider general relativity in terms of connection and vierbein variables and their corresponding first order actions. We focus on two main issues: (i) The role of the internal gauge freedom that exists, in the consistent formulations of the action principle, and (ii) the role that a 3  +  1 canonical decomposition has in the allowed internal gauge freedom. More concretely, we clarify in detail how the requirement of having well posed variational principles compatible with general weakly isolated horizons (WIHs) as internal boundaries does lead to a partial gauge fixing in the first order descriptions used previously in the literature. We consider the standard Hilbert–Palatini action together with the Holst extension (needed for a consistent 3  +  1 decomposition), with and without boundary terms at the horizon. We show in detail that, for the complete configuration space—with no gauge fixing—, while the Palatini action is differentiable without additional surface terms at the inner WIH boundary, the more general Holst action is not. The introduction of a surface term at the horizon—that renders the action for asymptotically flat configurations differentiable—does make the Holst action differentiable, but only if one restricts the configuration space and partially reduces the internal Lorentz gauge. For the second issue at hand, we show that upon performing a 3  +  1 decomposition and imposing the time gauge, there is a further gauge reduction of the Hamiltonian theory in terms of Ashtekar–Barbero variables to a U (1)-gauge theory on the horizon. We also extend our analysis to the more restricted boundary conditions of (strongly) isolated horizons as inner boundary. We show that even when

Lattice gauge theories and Monte Carlo simulations

International Nuclear Information System (INIS)

Rebbi, C.

1981-11-01

After some preliminary considerations, the discussion of quantum gauge theories on a Euclidean lattice takes up the definition of Euclidean quantum theory and treatment of the continuum limit; analogy is made with statistical mechanics. Perturbative methods can produce useful results for strong or weak coupling. In the attempts to investigate the properties of the systems for intermediate coupling, numerical methods known as Monte Carlo simulations have proved valuable. The bulk of this paper illustrates the basic ideas underlying the Monte Carlo numerical techniques and the major results achieved with them according to the following program: Monte Carlo simulations (general theory, practical considerations), phase structure of Abelian and non-Abelian models, the observables (coefficient of the linear term in the potential between two static sources at large separation, mass of the lowest excited state with the quantum numbers of the vacuum (the so-called glueball), the potential between two static sources at very small distance, the critical temperature at which sources become deconfined), gauge fields coupled to basonic matter (Higgs) fields, and systems with fermions

A geometric view on topologically massive gauge theories

International Nuclear Information System (INIS)

Horvathy, P.A.; Nash, C.

1985-01-01

The topologically massive gauge theory of Deser, Jackiw and Templeton is understood from Souriau's Principle of General Covariance. The non-gauge invariant mass term corresponds to a non-trivial class in the first cohomology group of configuration space, generated by the Chern-Simons secondary characteristic class. Quantization requires this class to be integral

Radionuclides gauges. Gauges designed for permanent installation

International Nuclear Information System (INIS)

1987-06-01

This present norm determines, for radionuclides gauges designed for permanent installation, the characteristics that these gauges should satisfied in their construction and performance to respect the prescriptions. It indicates the testing methods which permit to verify the agreement, gives a classification of gauges and specifies the indications to put on the emitter block [fr

Non-Abelian gauge fields

Science.gov (United States)

Gerbier, Fabrice; Goldman, Nathan; Lewenstein, Maciej; Sengstock, Klaus

2013-07-01

the progress in experimental studies of artificial Abelian and non-Abelian gauge fields in recent years has been simply spectacular. Multiple leading groups are working on this subject and have already obtained a lot of seminal results. The papers in the special issue are ordered according to the date of acceptance. The issue opens with a review article by Zhou et al [1] on unconventional states of bosons with synthetic spin-orbit coupling. Next, the paper by Maldonado-Mundo et al [2] studies ultracold Fermi gases with artificial Rashba spin-orbit coupling in a 2D gas. Anderson and Charles [3], in contrast, discuss a three-dimensional spin-orbit coupling in a trap. Orth et al [4] investigate correlated topological phases and exotic magnetism with ultracold fermions, again in the presence of artificial gauge fields. The paper of Nascimbène [5] does not address the synthetic gauge fields directly, but describes an experimental proposal for realizing one-dimensional topological superfluids with ultracold atomic gases; obviously, this problem is well situated in the general and growing field of topological superfluids, in particular those realized in the presence of non-Abelian gauge fields/spin-orbit coupling. Graß et al [6] consider in their paper fractional quantum Hall states of a Bose gas with spin-orbit coupling induced by a laser. Particular attention is drawn here to the possibility of realizing states with non-Abelian anyonic excitations. Zheng et al [7] study properties of Bose gases with Raman-induced spin-orbit coupling. Kiffner et al [8] in their paper touch on another kind of system, namely ultracold Rydberg atoms. In particular they study the generation of Abelian and non-Abelian gauge fields in dipole-dipole interacting Rydberg atoms. The behaviour of fermions in synthetic non-Abelian gauge potentials is discussed by Shenoy and Vyasanakere [9]. The paper starts with the study of Rashbon condensates (i.e. Bose condensates in the presence of Rashba

Infrared asymptotic behavior of gauge-invariant propagator in quantum electrodynamics

International Nuclear Information System (INIS)

Skachkov, N.B.; Solovtsov, I.L.; Shevchenko, O.Yu.

1987-01-01

A new class of gauge-invariant fields is introduced. The Dyson-Schwinger equations are obtained for the gauge-invariant generalization of the spinor propagator. On the basis of these equations, and also by means of functional methods, it is shown that the gauge-invariant spinor propagator has a singularity in the form of a simple pole in the infrared region

On classical solutions of SU(3) gauge field equations

International Nuclear Information System (INIS)

Chakrabarti, A.

1975-01-01

Static classical solutions of SU(3) gauge field equations are studied. The roles of the O(3) subgroup and of the quadrupole generators are discussed systematically. The general form thus obtained leads, through-out, to a high degree of symmetry in the results. This brings in some simplifying features. An octet of scalar mesons is finally added. Certain classes of exact solutions are given that are singular at the origin. A generalized gauge condition is pointed out. The relation of the general form to known particular cases is discussed [fr

On the WDVV equations in five-dimensional gauge theories

NARCIS (Netherlands)

Hoevenaars, L.K.; Martini, Ruud

2003-01-01

It is well known that the perturbative prepotentials of four-dimensional N = 2 supersymmetric Yang–Mills theories satisfy the generalized WDVV equations, regardless of the gauge group. In this Letter we study perturbative prepotentials of the five-dimensional theories for some classical gauge groups

Vortices, semi-local vortices in gauged linear sigma model

International Nuclear Information System (INIS)

Kim, Namkwon

1998-11-01

We consider the static (2+1)D gauged linear sigma model. By analyzing the governing system of partial differential equations, we investigate various aspects of the model. We show the existence of energy finite vortices under a partially broken symmetry on R 2 with the necessary condition suggested by Y. Yang. We also introduce generalized semi-local vortices and show the existence of energy finite semi-local vortices under a certain condition. The vacuum manifold for the semi-local vortices turns out to be graded. Besides, with a special choice of a representation, we show that the O(3) sigma model of which target space is nonlinear is a singular limit of the gauged linear sigma model of which target space is linear. (author)

Covariant gauges for constrained systems

International Nuclear Information System (INIS)

Gogilidze, S.A.; Khvedelidze, A.M.; Pervushin, V.N.

1995-01-01

The method of constructing of extended phase space for singular theories which permits the consideration of covariant gauges without the introducing of a ghost fields, is proposed. The extension of the phase space is carried out by the identification of the initial theory with an equivalent theory with higher derivatives and applying to it the Ostrogradsky method of Hamiltonian description. 7 refs

Extended Nambu models: Their relation to gauge theories

Science.gov (United States)

Escobar, C. A.; Urrutia, L. F.

2017-05-01

Yang-Mills theories supplemented by an additional coordinate constraint, which is solved and substituted in the original Lagrangian, provide examples of the so-called Nambu models, in the case where such constraints arise from spontaneous Lorentz symmetry breaking. Some explicit calculations have shown that, after additional conditions are imposed, Nambu models are capable of reproducing the original gauge theories, thus making Lorentz violation unobservable and allowing the interpretation of the corresponding massless gauge bosons as the Goldstone bosons arising from the spontaneous symmetry breaking. A natural question posed by this approach in the realm of gauge theories is to determine under which conditions the recovery of an arbitrary gauge theory from the corresponding Nambu model, defined by a general constraint over the coordinates, becomes possible. We refer to these theories as extended Nambu models (ENM) and emphasize the fact that the defining coordinate constraint is not treated as a standard gauge fixing term. At this level, the mechanism for generating the constraint is irrelevant and the case of spontaneous Lorentz symmetry breaking is taken only as a motivation, which naturally bring this problem under consideration. Using a nonperturbative Hamiltonian analysis we prove that the ENM yields the original gauge theory after we demand current conservation for all time, together with the imposition of the Gauss laws constraints as initial conditions upon the dynamics of the ENM. The Nambu models yielding electrodynamics, Yang-Mills theories and linearized gravity are particular examples of our general approach.

Fourier acceleration in lattice gauge theories. I. Landau gauge fixing

International Nuclear Information System (INIS)

Davies, C.T.H.; Batrouni, G.G.; Katz, G.R.; Kronfeld, A.S.; Lepage, G.P.; Wilson, K.G.; Rossi, P.; Svetitsky, B.

1988-01-01

Fourier acceleration is a useful technique which can be applied to many different numerical algorithms in order to alleviate the problem of critical slowing down. Here we describe its application to an optimization problem in the simulation of lattice gauge theories, that of gauge fixing a configuration of link fields to the Landau gauge (partial/sub μ/A/sup μ/ = 0). We find that a steepest-descents method of gauge fixing link fields at β = 5.8 on an 8 4 lattice can be made 5 times faster using Fourier acceleration. This factor will grow as the volume of the lattice is increased. We also discuss other gauges that are useful to lattice-gauge-theory simulations, among them one that is a combination of the axial and Landau gauges. This seems to be the optimal gauge to impose for the Fourier acceleration of two other important algorithms, the inversion of the fermion matrix and the updating of gauge field configurations

Supergravity duals of supersymmetric four dimensional gauge theories

Energy Technology Data Exchange (ETDEWEB)

Bigazzi, F [Abdus Salam International Centre for Theoretical Physics, Trieste (Italy); Cotrone, A L [Centre de Physique Theorique, Ecole Polytechnique, Palaiseau Cedex (France); [INFN, Rome (Italy); Petrini, M [Centre de Physique Theorique, Ecole Polytechnique, Palaiseau (France); Zaffaroni, A [Universita di Milano-Bicocca and INFN, Milan (Italy)

2002-03-01

This article contains an overview of some recent attempts of understanding supergravity and string duals of four dimensional gauge theories using the AdS/CFT correspondence. We discuss the general philosophy underlying the various ways to realize Super Yang-Mills theories in terms of systems of branes. We then review some of the existing duals for N=2 and N=1 theories. We also discuss differences and similarities with realistic theories. (author)

Manifestly gauge invariant discretizations of the Schrödinger equation

International Nuclear Information System (INIS)

Halvorsen, Tore Gunnar; Kvaal, Simen

2012-01-01

Grid-based discretizations of the time dependent Schrödinger equation coupled to an external magnetic field are converted to manifest gauge invariant discretizations. This is done using generalizations of ideas used in classical lattice gauge theory, and the process defined is applicable to a large class of discretized differential operators. In particular, popular discretizations such as pseudospectral discretizations using the fast Fourier transform can be transformed to gauge invariant schemes. Also generic gauge invariant versions of generic time integration methods are considered, enabling completely gauge invariant calculations of the time dependent Schrödinger equation. Numerical examples illuminating the differences between a gauge invariant discretization and conventional discretization procedures are also presented. -- Highlights: ► We investigate the Schrödinger equation coupled to an external magnetic field. ► Any grid-based discretization is made trivially gauge invariant. ► An extension of classical lattice gauge theory.

Ice limit of Coulomb gauge Yang-Mills theory

International Nuclear Information System (INIS)

Heinzl, T.; Ilderton, A.; Langfeld, K.; Lavelle, M.; McMullan, D.

2008-01-01

In this paper we describe gauge invariant multiquark states generalizing the path integral framework developed by Parrinello, Jona-Lasinio, and Zwanziger to amend the Faddeev-Popov approach. This allows us to produce states such that, in a limit which we call the ice limit, fermions are dressed with glue exclusively from the fundamental modular region associated with Coulomb gauge. The limit can be taken analytically without difficulties, avoiding the Gribov problem. This is illustrated by an unambiguous construction of gauge invariant mesonic states for which we simulate the static quark-antiquark potential.

46 CFR 52.01-110 - Water-level indicators, water columns, gauge-glass connections, gauge cocks, and pressure gauges...

Science.gov (United States)

2010-10-01

... § 52.01-110 Water-level indicators, water columns, gauge-glass connections, gauge cocks, and pressure... 46 Shipping 2 2010-10-01 2010-10-01 false Water-level indicators, water columns, gauge-glass connections, gauge cocks, and pressure gauges (modifies PG-60). 52.01-110 Section 52.01-110 Shipping COAST...

Gauge invariant fractional electromagnetic fields

International Nuclear Information System (INIS)

Lazo, Matheus Jatkoske

2011-01-01

Fractional derivatives and integrations of non-integers orders was introduced more than three centuries ago but only recently gained more attention due to its application on nonlocal phenomenas. In this context, several formulations of fractional electromagnetic fields was proposed, but all these theories suffer from the absence of an effective fractional vector calculus, and in general are non-causal or spatially asymmetric. In order to deal with these difficulties, we propose a spatially symmetric and causal gauge invariant fractional electromagnetic field from a Lagrangian formulation. From our fractional Maxwell's fields arose a definition for the fractional gradient, divergent and curl operators. -- Highlights: → We propose a fractional Lagrangian formulation for fractional Maxwell's fields. → We obtain gauge invariant fractional electromagnetic fields. → Our generalized fractional Maxwell's field is spatially symmetrical. → We discuss the non-causality of the theory.

Gauge invariance properties and singularity cancellations in a modified PQCD

CERN Document Server

Cabo-Montes de Oca, Alejandro; Cabo, Alejandro; Rigol, Marcos

2006-01-01

The gauge-invariance properties and singularity elimination of the modified perturbation theory for QCD introduced in previous works, are investigated. The construction of the modified free propagators is generalized to include the dependence on the gauge parameter $\\alpha $. Further, a functional proof of the independence of the theory under the changes of the quantum and classical gauges is given. The singularities appearing in the perturbative expansion are eliminated by properly combining dimensional regularization with the Nakanishi infrared regularization for the invariant functions in the operator quantization of the $\\alpha$-dependent gauge theory. First-order evaluations of various quantities are presented, illustrating the gauge invariance-properties.

Gauge theories

International Nuclear Information System (INIS)

Lee, B.W.

1976-01-01

Some introductory remarks to Yang-Mills fields are given and the problem of the Coulomb gauge is considered. The perturbation expansion for quantized gauge theories is discussed and a survey of renormalization schemes is made. The role of Ward-Takahashi identities in gauge theories is discussed. The author then discusses the renormalization of pure gauge theories and theories with spontaneously broken symmetry. (B.R.H.)

Nucleonic gauging

International Nuclear Information System (INIS)

Bond, A.

1977-01-01

The present position of nucleonic techniques for process measurements, is considered from the technical and cost viewpoints. Systems considered include level, density, thickness (including coating thickness), moisture, and sulphur in hydrocarbons gauges and also belt weighers. The advantages of such systems are discussed and the cost-benefit position considered. The combination of nucleonic measuring equipment with a microcomputer is examined. (U.K.)

Nucleonic gauges

International Nuclear Information System (INIS)

Sowerby, B.D.

1982-01-01

Techniques employed in nuclear gauges for the measurement of level, thickness, density and moisture are described. The gauges include both transmission and backscatter gauges and utilize alpha particles, beta particles, neutrons or gamma radiation

Gauge properties of the guiding center variational symplectic integrator

International Nuclear Information System (INIS)

Squire, J.; Tang, W. M.; Qin, H.

2012-01-01

Variational symplectic algorithms have recently been developed for carrying out long-time simulation of charged particles in magnetic fields [H. Qin and X. Guan, Phys. Rev. Lett. 100, 035006 (2008); H. Qin, X. Guan, and W. Tang, Phys. Plasmas (2009); J. Li, H. Qin, Z. Pu, L. Xie, and S. Fu, Phys. Plasmas 18, 052902 (2011)]. As a direct consequence of their derivation from a discrete variational principle, these algorithms have very good long-time energy conservation, as well as exactly preserving discrete momenta. We present stability results for these algorithms, focusing on understanding how explicit variational integrators can be designed for this type of system. It is found that for explicit algorithms, an instability arises because the discrete symplectic structure does not become the continuous structure in the t→0 limit. We examine how a generalized gauge transformation can be used to put the Lagrangian in the “antisymmetric discretization gauge,” in which the discrete symplectic structure has the correct form, thus eliminating the numerical instability. Finally, it is noted that the variational guiding center algorithms are not electromagnetically gauge invariant. By designing a model discrete Lagrangian, we show that the algorithms are approximately gauge invariant as long as A and φ are relatively smooth. A gauge invariant discrete Lagrangian is very important in a variational particle-in-cell algorithm where it ensures current continuity and preservation of Gauss’s law [J. Squire, H. Qin, and W. Tang (to be published)].

Gravitationally induced zero modes of the Faddeev-Popov operator in the Coulomb gauge for Abelian gauge theories

Science.gov (United States)

Canfora, Fabrizio; Giacomini, Alex; Oliva, Julio

2010-08-01

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.

Multigrid methods for the computation of propagators in gauge fields

International Nuclear Information System (INIS)

Kalkreuter, T.

1992-11-01

In the present work generalizations of multigrid methods for propagators in gauge fields are investigated. We discuss proper averaging operations for bosons and for staggered fermions. An efficient algorithm for computing C numerically is presented. The averaging kernels C can be used not only in deterministic multigrid computations, but also in multigrid Monte Carlo simulations, and for the definition of block spins and blocked gauge fields in Monte Carlo renormalization group studies of gauge theories. Actual numerical computations of kernels and propagators are performed in compact four-dimensional SU(2) gauge fields. (orig./HSI)

Gauge theory of amorphous magnets

International Nuclear Information System (INIS)

Nesterov, A.I.; Ovchinnikov, S.G.

1989-01-01

A gauge theory of disordered magnets as a field theory in the principal fiber bundle with structure group SL(3, R) is constructed. The gauge field interacting with a vector field (the magnetization) is responsible for the disorder. A complete system of equations, valid for arbitrary disordered magnets, is obtained. In the limiting case of a free gauge field the proposed approach leads to the well-known Volovik-Dzyaloshinskii theory, which describes isotropic spin glasses. In the other limiting case when the curvature is zero the results of Ignatchenko and Iskhakov for weakly disordered ferromagnets are reproduced

Vacuum gauges

International Nuclear Information System (INIS)

Power, B.D.; Priestland, C.R.D.

1978-01-01

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)

Quantum communication, reference frames, and gauge theory

International Nuclear Information System (INIS)

Enk, S. J. van

2006-01-01

We consider quantum communication in the case that the communicating parties not only do not share a reference frame but use imperfect quantum communication channels, in that each channel applies some fixed but unknown unitary rotation to each qubit. We discuss similarities and differences between reference frames within that quantum communication model and gauge fields in gauge theory. We generalize the concept of refbits and analyze various quantum communication protocols within the communication model

Some new applications of nucleonic gauges in Russia

International Nuclear Information System (INIS)

Fedorkov, V.G.

2000-01-01

Russia has been a big producer of nucleonic gauges for many years. There are still some institutions that design and manufacture nucleonic gauges for industry, like level gauges, density gauges and thickness gauges. Industrial demands for NCS (especially after the Chernobyl accident) have been decreasing. Examples of recent development are given in this paper. Substantial improvements in the hardware, source and detectors system, are being undertaken. The potential for new applications is large, also, there is a good capability of local researchers for increasing the quality and quantity of nucleonic gauges in industry to meet local needs and to compete better in the international scale and market. (author)

Review of lattice supersymmetry and gauge-gravity duality

International Nuclear Information System (INIS)

Joseph, Anosh

2015-12-01

We review the status of recent investigations on validating the gauge-gravity duality conjecture through numerical simulations of strongly coupled maximally supersymmetric thermal gauge theories. In the simplest setting, the gauge-gravity duality connects systems of D0-branes and black hole geometries at finite temperature to maximally supersymmetric gauged quantum mechanics at the same temperature. Recent simulations show that non-perturbative gauge theory results give excellent agreement with the quantum gravity predictions, thus proving strong evidence for the validity of the duality conjecture and more insight into quantum black holes and gravity.

Jet quenching parameters in strongly coupled nonconformal gauge theories

International Nuclear Information System (INIS)

Buchel, Alex

2006-01-01

Recently Liu, Rajagopal, and Wiedemann (LRW) [H. Liu, K. Rajagopal, and U. A. Wiedemann, hep-ph/0605178.] proposed a first principle, nonperturbative quantum field theoretic definition of 'jet quenching parameter' q-circumflex used in models of medium-induced radiative parton energy loss in nucleus-nucleus collisions at RHIC. Relating q-circumflex to a short-distance behavior of a certain lightlike Wilson loop, they used gauge theory-string theory correspondence to evaluate q-circumflex for the strongly coupled N=4 SU(N c ) gauge theory plasma. We generalize analysis of LRW to strongly coupled nonconformal gauge theory plasma. We find that a jet quenching parameter is gauge theory specific (not universal). Furthermore, it appears its value increases as the number of effective adjoint degrees of freedom of a gauge theory plasma increases

Numerical techniques for lattice gauge theories

International Nuclear Information System (INIS)

Creutz, M.

1981-01-01

The motivation for formulating gauge theories on a lattice is reviewed. Monte Carlo simulation techniques are then discussed for these systems. Finally, the Monte Carlo methods are combined with renormalization group analysis to give strong numerical evidence for confinement of quarks by non-Abelian gauge fields

Fluctuations around classical solutions for gauge theories in Lagrangian and Hamiltonian approach

International Nuclear Information System (INIS)

Miskovic, Olivera; Pons, Josep M

2006-01-01

We analyse the dynamics of gauge theories and constrained systems in general under small perturbations around a classical solution in both Lagrangian and Hamiltonian formalisms. We prove that a fluctuations theory, described by a quadratic Lagrangian, has the same constraint structure and number of physical degrees of freedom as the original non-perturbed theory, assuming the non-degenerate solution has been chosen. We show that the number of Noether gauge symmetries is the same in both theories, but that the gauge algebra in the fluctuations theory becomes Abelianized. We also show that the fluctuations theory inherits all functionally independent rigid symmetries from the original theory and that these symmetries are generated by linear or quadratic generators according to whether the original symmetry is preserved by the background or is broken by it. We illustrate these results with examples

Lattice gauge theory approach to quantum chromodynamics

International Nuclear Information System (INIS)

Kogut, J.B.

1983-01-01

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

Gauge invariant fractional electromagnetic fields

Energy Technology Data Exchange (ETDEWEB)

Lazo, Matheus Jatkoske, E-mail: matheuslazo@furg.br [Instituto de Matematica, Estatistica e Fisica - FURG, Rio Grande, RS (Brazil)

2011-09-26

Fractional derivatives and integrations of non-integers orders was introduced more than three centuries ago but only recently gained more attention due to its application on nonlocal phenomenas. In this context, several formulations of fractional electromagnetic fields was proposed, but all these theories suffer from the absence of an effective fractional vector calculus, and in general are non-causal or spatially asymmetric. In order to deal with these difficulties, we propose a spatially symmetric and causal gauge invariant fractional electromagnetic field from a Lagrangian formulation. From our fractional Maxwell's fields arose a definition for the fractional gradient, divergent and curl operators. -- Highlights: → We propose a fractional Lagrangian formulation for fractional Maxwell's fields. → We obtain gauge invariant fractional electromagnetic fields. → Our generalized fractional Maxwell's field is spatially symmetrical. → We discuss the non-causality of the theory.

The string unification of gauge couplings and gauge kinetic mixings

International Nuclear Information System (INIS)

Hattori, Chuichiro; Matsuda, Masahisa; Matsuoka, Takeo; Mochinaga, Daizo.

1993-01-01

In the superstring models we have not only the complete 27 multiplets of E 6 but also extra incomplete (27+27-bar) chiral supermultiplets being alive at low energies. Associated with these additional multiplets, when the gauge symmetry contains more than one U(1) gauge group, there may exist gauge kinetic mixings among these U(1) gauge groups. In such cases the effect of gauge kinetic mixings should be incorporated into the study of unification of gauge couplings. We study these interesting effects systematically in these models. The string threshold effect is also taken into account. It is found that in the four-generation models we do not have an advisable solution of string unification of gauge couplings consistent with experimental values at the electroweak scale. We also discuss the possible scenarios to solve this problem. (author)

Second quantization, projective modules, and local gauge invariance

Energy Technology Data Exchange (ETDEWEB)

Selesnick, S A [Missouri Univ., St. Louis (USA)

1983-01-01

Bundles and bundle structures have gained wide currency in modern approaches to certain topics in quantum physics, significant applications appearing in connection with gauge theories, theories of geometric quantization, and in numerous other contexts. It is argued that such structures can already be discerned in the most elementary notions of second quantization. An examination of the methods traditionally used by physicists in dealing quantum mechanically with systems exhibiting an infinite number of degrees of freedom reveals the implicit use of module structures over algebras of functions. By making these structures explicit and adapting some results of perturbation theory an association between bare particles and finitely generated projective modules is arrived at. In particular, rank one modules emerge naturally, for algebraic reasons, as the appropriate descriptors of bosons in this association. As a first application of the formalism the existence of phononlike excitations in general many-fermion systems is shown. When these ideas are further specialized (local) gauge theoretical notions arise in a natural way out of a consideration of the bundles.

Beltrami parametrization and gauging of Virasoro and w-infinity algebras

International Nuclear Information System (INIS)

Tatar, L.

1992-07-01

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

Derivation of the Finslerian gauge field equations

International Nuclear Information System (INIS)

Asanov, G.S.

1984-01-01

As is well known the simplest way of formulating the equations for the Yang-Mills gauge fields consists in taking the Lagrangian to be quadratic in the gauge tensor, whereas the application of such an approach to the gravitational field yields equations which are of essentially more complicated structure than the Einstein equations. On the other hand, in the gravitational field theory the Lagrangian can be constructed to be of forms which may be both quadratic and linear in the curvature tensor, whereas the latter possibility is absent in the current gauge field theories. In previous work it has been shown that the Finslerian structure of the space-time gives rise to certain gauge fields provided that the internal symmetries may be regarded as symmetries of a three-dimensional Riemannian space. Continuing this work we show that appropriate equations for these gauge fields can be formulated in both ways, namely on the basis of the quadratic Lagrangian or, if a relevant generalization of the Palatini method is applied, on the basis of a Lagrangian linear in the gauge field strength tensor. The latter possibility proves to result in equations which are similar to the Einstein equations, a distinction being that the Finslerian Cartan curvature tensor rather then the Riemann curvature tensor enters the equations. (author)

Gauge Theories of Vector Particles

Science.gov (United States)

Glashow, S. L.; Gell-Mann, M.

1961-04-24

The possibility of generalizing the Yang-Mills trick is examined. Thus we seek theories of vector bosons invariant under continuous groups of coordinate-dependent linear transformations. All such theories may be expressed as superpositions of certain "simple" theories; we show that each "simple theory is associated with a simple Lie algebra. We may introduce mass terms for the vector bosons at the price of destroying the gauge-invariance for coordinate-dependent gauge functions. The theories corresponding to three particular simple Lie algebras - those which admit precisely two commuting quantum numbers - are examined in some detail as examples. One of them might play a role in the physics of the strong interactions if there is an underlying super-symmetry, transcending charge independence, that is badly broken. The intermediate vector boson theory of weak interactions is discussed also. The so-called "schizon" model cannot be made to conform to the requirements of partial gauge-invariance.

Introduction to lattice gauge theories

International Nuclear Information System (INIS)

La Cock, P.

1988-03-01

A general introduction to Lattice Gauge Theory (LGT) is given. The theory is discussed from first principles to facilitate an understanding of the techniques used in LGT. These include lattice formalism, gauge invariance, fermions on the lattice, group theory and integration, strong coupling methods and mean field techniques. A review of quantum chromodynamics on the lattice at finite temperature and density is also given. Monte Carlo results and analytical methods are discussed. An attempt has been made to include most relevant data up to the end of 1987, and to update some earlier reviews existing on the subject. 224 refs., 33 figs., 14 tabs

Gauge theories, duality relations and the tensor hierarchy

International Nuclear Information System (INIS)

Bergshoeff, Eric A.; Hohm, Olaf; Hartong, Jelle; Huebscher, Mechthild; OrtIn, Tomas

2009-01-01

We compute the complete 3- and 4-dimensional tensor hierarchies, i.e. sets of p-form fields, with 1 ≤ p ≤ D, which realize an off-shell algebra of bosonic gauge transformations. We show how these tensor hierarchies can be put on-shell by introducing a set of duality relations, thereby introducing additional scalars and a metric tensor. These so-called duality hierarchies encode the equations of motion of the bosonic part of the most general gauged supergravity theories in those dimensions, including the (projected) scalar equations of motion. We construct gauge-invariant actions that include all the fields in the tensor hierarchies. We elucidate the relation between the gauge transformations of the p-form fields in the action and those of the same fields in the tensor hierarchy.

A finite size scaling test of an SU(2) gauge-spin system

International Nuclear Information System (INIS)

Tomiya, M.; Hattori, T.

1984-01-01

We calculate the correlation functions in the SU(2) gauge-spin system with spins in the fundamental representation. We analyze the result making use of finite size scaling. There is a possibility that there are no second order phase transition lines in this model, contrary to previous assertions. (orig.)

A strain gauge

DEFF Research Database (Denmark)

2016-01-01

The invention relates to a strain gauge of a carrier layer and a meandering measurement grid positioned on the carrier layer, wherein the strain gauge comprises two reinforcement members positioned on the carrier layer at opposite ends of the measurement grid in the axial direction....... The reinforcement members are each placed within a certain axial distance to the measurement grid with the axial distance being equal to or smaller than a factor times the grid spacing. The invention further relates to a multi-axial strain gauge such as a bi-axial strain gauge or a strain gauge rosette where each...... of the strain gauges comprises reinforcement members. The invention further relates to a method for manufacturing a strain gauge as mentioned above....

Gauge theory of things alive and universal dynamics

International Nuclear Information System (INIS)

Mack, G.

1994-10-01

Positing complex adaptive systems made of agents with relations between them that can be composed, it follows that they can be described by gauge theories similar to elementary particle theory and general relativity. By definition, a universal dynamics is able to determine the time development of any such system without need for further specification. The possibilities are limited, but one of them - reproduction fork dynamics - describes DNA replication and is the basis of biological life on earth. It is a universal copy machine and a renormalization group fixed point. A universal equation of motion in continuous time is also presented. (orig.)

Remarks on gauge variables and singular Lagrangians

International Nuclear Information System (INIS)

Chela-Flores, J.; Janica-de-la-Torre, R.; Kalnay, A.J.; Rodriguez-Gomez, J.; Rodriguez-Nunez, J.; Tascon, R.

1977-01-01

The relevance is discussed of gauge theory, based on a singular Lagrangian density, to the foundations of field theory. The idea that gauge transformations could change the physics of systems where the Lagrangian is singular is examined. (author)

Superaxial gauges

International Nuclear Information System (INIS)

Kummer, W.; Mistelberger, H.; Schaller, P.; Schweda, M.

1989-01-01

Supersymmetric gauge theories can be suitably quantized in non-supersymmetric 'superaxial' gauges without abolishing the basic advantages of the superfield technique. In this review the state of the art is presented. It includes the proof of renormalization and the proof of gauge independence and supersymmetry of observable physical quantities. (author)

Schwinger mechanism in linear covariant gauges

Science.gov (United States)

Aguilar, A. C.; Binosi, D.; Papavassiliou, J.

2017-02-01

In this work we explore the applicability of a special gluon mass generating mechanism in the context of the linear covariant gauges. In particular, the implementation of the Schwinger mechanism in pure Yang-Mills theories hinges crucially on the inclusion of massless bound-state excitations in the fundamental nonperturbative vertices of the theory. The dynamical formation of such excitations is controlled by a homogeneous linear Bethe-Salpeter equation, whose nontrivial solutions have been studied only in the Landau gauge. Here, the form of this integral equation is derived for general values of the gauge-fixing parameter, under a number of simplifying assumptions that reduce the degree of technical complexity. The kernel of this equation consists of fully dressed gluon propagators, for which recent lattice data are used as input, and of three-gluon vertices dressed by a single form factor, which is modeled by means of certain physically motivated Ansätze. The gauge-dependent terms contributing to this kernel impose considerable restrictions on the infrared behavior of the vertex form factor; specifically, only infrared finite Ansätze are compatible with the existence of nontrivial solutions. When such Ansätze are employed, the numerical study of the integral equation reveals a continuity in the type of solutions as one varies the gauge-fixing parameter, indicating a smooth departure from the Landau gauge. Instead, the logarithmically divergent form factor displaying the characteristic "zero crossing," while perfectly consistent in the Landau gauge, has to undergo a dramatic qualitative transformation away from it, in order to yield acceptable solutions. The possible implications of these results are briefly discussed.

N=2 vacua in electrically gauged N=4 supergravities

Energy Technology Data Exchange (ETDEWEB)

Horst, Christoph

2013-06-15

In this thesis we study N= 2 vacua in gauged N=4 supergravity theories in fourdimensional spacetime. Using the embedding tensor formalism that describes general consistent magnetic gaugings of an ungauged N=4 matter-coupled supergravity theory in a symplectic frame with SO(1,1) x SO(6,n) off-shell symmetry we formulate necessary conditions for partial supersymmetry breaking and find that the Killing spinor equations can be solved for the embedding tensor components. Subsequently, we show that the classification of theories that allow for vacua with partial supersymmetry amounts to solving a system of purely algebraic quadratic equations. Then, we restrict ourselves to the class of purely electric gaugings and explicitly construct a class of consistent super-Higgs mechanisms and study its properties. In particular, we find that the spectrum fills complete N=2 supermultiplets that are either massless or BPS. Furthermore, we demonstrate that (modulo an abelian Lie algebra) arbitrary unbroken gauge Lie algebras can be realized provided that the number of N=4 vector multiplets is sufficiently large. Finally, we compute the relevant terms of the effective action below the scale of partial supersymmetry breaking and argue that the special Kaehler manifold for the scalars of the N=2 vector multiplets has to be in the unique series of special Kaehler product manifolds.

Towards a unified picture for gauge and Higgs fields

International Nuclear Information System (INIS)

Mecklenburg, W.

1981-01-01

A scheme for a geometrical unification of gauge and Higgs fields, previously given for SU 2 , is generalized to include arbitrary semisimple gauge groups. Gauge and physical Higgs fields appear as different components of the same tensor in a high dimensional manifold, the higher dimensions being comprised by the group coordinates. Their respective inhomogeneous transformation behaviour is derived from the same principle. The number of Higgs fields is restricted. The form of the Higgs potential is fixed and the mass of the Higgs particle is predicted in terms of the vector boson mass. (author)

Gauge fixing and classical dynamical r-matrices in (2+1)-gravity

International Nuclear Information System (INIS)

Schoenfeld, Torsten

2012-01-01

We apply the Dirac gauge fixing procedure to the combinatorial description of the moduli space of flat ISO(2,1)-connections. This is motivated by two goals: one originates from physics while the other is of a mathematical nature. The first goal is to investigate the application of gauge fixing in Lorentzian (2+1)-gravity with vanishing cosmological constant, whose phase space is closely related to the moduli space of flat ISO(2,1)-connections. To this end, we first show that specifying gauge fixing conditions amounts to introducing an observer into the theory. Then we determine explicit expressions for the Dirac brackets of specific sets of gauge fixing conditions and give a physical interpretation of the results in terms of the geometry of spacetimes and their effective symmetries. To investigate the mathematical structures underlying the Dirac gauge fixing procedure we then consider general gauge fixing conditions. We first show that the resulting Dirac brackets are in one-to-one correspondence with solutions of the classical dynamical Yang-Baxter equation. We then analyze the relation between the Dirac brackets associated with two different sets of gauge fixing conditions. We find that this relation is given by the action of certain dynamical Poincare transformations which generalize the gauge transformations of classical dynamical r-matrices. Using these transformations, we give a classification of all resulting Dirac brackets and the associated solutions of the classical dynamical Yang-Baxter equation.

Gauge fixing and classical dynamical r-matrices in (2+1)-gravity

Energy Technology Data Exchange (ETDEWEB)

Schoenfeld, Torsten

2012-11-20

We apply the Dirac gauge fixing procedure to the combinatorial description of the moduli space of flat ISO(2,1)-connections. This is motivated by two goals: one originates from physics while the other is of a mathematical nature. The first goal is to investigate the application of gauge fixing in Lorentzian (2+1)-gravity with vanishing cosmological constant, whose phase space is closely related to the moduli space of flat ISO(2,1)-connections. To this end, we first show that specifying gauge fixing conditions amounts to introducing an observer into the theory. Then we determine explicit expressions for the Dirac brackets of specific sets of gauge fixing conditions and give a physical interpretation of the results in terms of the geometry of spacetimes and their effective symmetries. To investigate the mathematical structures underlying the Dirac gauge fixing procedure we then consider general gauge fixing conditions. We first show that the resulting Dirac brackets are in one-to-one correspondence with solutions of the classical dynamical Yang-Baxter equation. We then analyze the relation between the Dirac brackets associated with two different sets of gauge fixing conditions. We find that this relation is given by the action of certain dynamical Poincare transformations which generalize the gauge transformations of classical dynamical r-matrices. Using these transformations, we give a classification of all resulting Dirac brackets and the associated solutions of the classical dynamical Yang-Baxter equation.

Representation of a gauge field via intrinsic “BRST” operator

Energy Technology Data Exchange (ETDEWEB)

Batalin, Igor A., E-mail: batalin@lpi.ru [P.N. Lebedev Physical Institute, Leninsky Prospect 53, 119 991 Moscow (Russian Federation); Tomsk State Pedagogical University, Kievskaya St. 60, 634061 Tomsk (Russian Federation); Lavrov, Peter M., E-mail: lavrov@tspu.edu.ru [Tomsk State Pedagogical University, Kievskaya St. 60, 634061 Tomsk (Russian Federation); National Research Tomsk State University, Lenin Ave. 36, 634050 Tomsk (Russian Federation)

2015-11-12

We show that there exists a representation of a matrix-valued gauge field via intrinsic “BRST” operator assigned to matrix-valued generators of a gauge algebra. In this way, we reproduce the standard formulation of the ordinary Yang–Mills theory. In the case of a generating quasigroup/groupoid, we give a natural counterpart to the Yang–Mills action. The latter counterpart does also apply as to the most general case of an involution for matrix-valued gauge generators.

Manipulating novel quantum phenomena using synthetic gauge fields

Science.gov (United States)

Zhang, Shao-Liang; Zhou, Qi

2017-11-01

The past few years have seen fascinating progress in the creation and utilization of synthetic gauge fields for charge-neutral ultracold atoms. Whereas the synthesis of gauge fields in itself is readily interesting, it is more exciting to explore the new era that will be brought by the interplay between synthetic gauge fields and many other degrees of freedom of highly tunable ultracold atoms. This topical review surveys recent developments in using synthetic gauge fields to manipulate novel quantum phenomena that are not easy to access in other systems. We first summarize current experimental methods of creating synthetic gauge fields, including the use of Raman schemes, shaken lattices, and Raman-dressed lattices. We then discuss how synthetic gauge fields bring new physics to non-interacting systems, including degenerate single-particle ground states, quartic dispersions, topological band structures in lattices, and synthetic dimensions. As for interacting systems, we focus on novel quantum many-body states and quantum macroscopic phenomena induced by interactions in the presence of unconventional single-particle dispersions. For bosons, we discuss how a quartic dispersion leads to non-condensed bosonic states at low temperatures and at the ground state. For fermions, we discuss chiral superfluids in the presence of attractive s-wave interaction, where high partial-wave interactions are not required. Finally, we discuss the challenges in current experiments, and conclude with an outlook for what new exciting developments synthetic gauge fields may bring us in the near future.

Gauged Supergravities and Spontaneous Supersymmetry Breaking from the Double Copy Construction

Science.gov (United States)

Chiodaroli, M.; Günaydin, M.; Johansson, H.; Roiban, R.

2018-04-01

Supergravities with gauged R symmetry and Minkowski vacua allow for spontaneous supersymmetry breaking and, as such, provide a framework for building supergravity models of phenomenological relevance. In this Letter, we initiate the study of double copy constructions for these supergravities. We argue that, on general grounds, we expect their scattering amplitudes to be described by a double copy of the type (spontaneously broken gauge theory)⊗ (gauge theory with broken supersymmetry). We present a simple realization in which the resulting supergravity has U (1 )R gauge symmetry, spontaneously broken N =2 supersymmetry, and massive gravitini. This is the first instance of a double copy construction of a gauged supergravity and of a theory with spontaneously broken supersymmetry. The construction extends in a straightforward manner to a large family of gauged Yang-Mills-Einstein supergravity theories with or without spontaneous gauge-symmetry breaking.

Interplay of infrared divergences and gauge-dependence of the effective potential

International Nuclear Information System (INIS)

Espinosa, J.R.; Garny, M.; Konstandin, T.

2016-07-01

The perturbative effective potential suffers infrared (IR) divergences in gauges with massless Goldstones in their minima (like Landau or Fermi gauges) but the problem can be fixed by a suitable resummation of the Goldstone propagators. When the potential minimum is generated radiatively, gauge-independence of the potential at the minimum also requires resummation and we demonstrate that the resummation that solves the IR problem also cures the gauge-dependence issue, showing this explicitly in the Abelian Higgs model in Fermi gauge. In the process we find an IR divergence (in the location of the minimum) specific to Fermi gauge and not appreciated in recent literature. We show that physical observables can still be computed in this gauge and we further show how to get rid of this divergence by a field redefinition. All these results generalize to the Standard Model case.

Interplay of Infrared Divergences and Gauge-Dependence of the Effective Potential

CERN Document Server

Espinosa, J.R.; Konstandin, T.

2016-01-01

The perturbative effective potential suffers infrared (IR) divergences in gauges with massless Goldstones in their minima (like Landau or Fermi gauges) but the problem can be fixed by a suitable resummation of the Goldstone propagators. When the potential minimum is generated radiatively, gauge-independence of the potential at the minimum also requires resummation and we demonstrate that the resummation that solves the IR problem also cures the gauge-dependence issue, showing this explicitly in the Abelian Higgs model in Fermi gauge. In the process we find an IR divergence (in the location of the minimum) specific to Fermi gauge and not appreciated in recent literature. We show that physical observables can still be computed in this gauge and we further show how to get rid of this divergence by a field redefinition. All these results generalize to the Standard Model case.

Revisiting entanglement entropy of lattice gauge theories

Energy Technology Data Exchange (ETDEWEB)

Hung, Ling-Yan [Department of Physics and Center for Field Theory and Particle Physics, Fudan University,220 Handan Lu, Shanghai 200433 (China); Collaborative Innovation Center of Advanced Microstructures, Fudan University,220 Handan Lu, Shanghai 200433 (China); Wan, Yidun [Perimeter Institute for Theoretical Physics,31 Caroline Street, Waterloo, ON N2L 2Y5 (Canada)

2015-04-22

It is realized recently that the entanglement entropy in gauge theories is ambiguous because the Hilbert space cannot be expressed as a simple direct product of Hilbert spaces defined on the two regions; different ways of dividing the Hilbert spaces near the boundary leads to significantly different result, to the extreme that it could annihilate the otherwise finite topological entanglement entropy between two regions altogether. In this article, we first show that the topological entanglement entropy in the Kitaev model http://dx.doi.org/10.1016/S0003-4916(02)00018-0 which is not a true gauge theory, is free of ambiguity. Then, we give a physical interpretation, from the perspectives of what can be measured in an experiment, to the purported ambiguity of true gauge theories, where the topological entanglement arises as redundancy in counting the degrees of freedom along the boundary separating two regions. We generalize these discussions to non-Abelian gauge theories.

Effective lagrangian description on discrete gauge symmetries

International Nuclear Information System (INIS)

Banks, T.

1989-01-01

We exhibit a simple low-energy lagrangian which describes a system with a discrete remnant of a spontaneously broken continuous gauge symmetry. The lagrangian gives a simple description of the effects ascribed to such systems by Krauss and Wilczek: black holes carry discrete hair and interact with cosmic strings, and wormholes cannot lead to violation of discrete gauge symmetries. (orig.)

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

International Nuclear Information System (INIS)

Mitrut, Alexandru

2002-01-01

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)

Finite Element Model of the Strain Gauge For Determining Uniaxial Tension

Directory of Open Access Journals (Sweden)

Vladimír GOGA

2013-12-01

Full Text Available Strain gauge is device used to measure the mechanical strains of solid bodies. Deformation of the strain gauge element causes changes its electrical resistance. This resistance change, usually measured using a Wheatstone bridge, is related to the strain by the quantity known as the gauge factor. When the stains are known, it is possible to determined state of stress at a point of measured body using generalized Hooke`s law and Mohr`s circle. Finite element analysis of strain gauge measurement using ANSYS software is subject of this article.

Monte Carlo studies of non-Abelian gauge theories

International Nuclear Information System (INIS)

Creutz, M.

1980-05-01

After some general remarks on the efficiency of various Monte Carlo algorithms for gauge theories, the calculation of the asymptotic freedom scales of SU(2) and SU(3) gauge theories in the absence of quarks was discussed. There are large numerical factors between these scales when defined in terms of the bare coupling of the lattice theory or when defined in terms of the physical force between external sources

Kinetic mixing and the supersymmetric gauge hierarchy

International Nuclear Information System (INIS)

Dienes, K.R.; Kolda, C.; March-Russell, J.

1997-01-01

The most general Lagrangian for a model with two U(1) gauge symmetries contains a renormalizable operator which mixes their gauge kinetic terms. Such kinetic mixing can be generated at arbitrarily high scales but will not be suppressed by large masses. In models whose supersymmetry (SUSY)-breaking hidden sectors contain U(1) gauge factors, we show that such terms will generically arise and communicate SUSY breaking to the visible sector through mixing with hypercharge. In the context of the usual supergravity- or gauge-mediated communication scenarios with D-terms of order the fundamental scale of SUSY breaking, this effect can destabilize the gauge hierarchy. Even in models for which kinetic mixing is suppressed or the D-terms are arranged to be small, this effect is a potentially large correction to the soft scalar masses and therefore introduces a new measurable low-energy parameter. We calculate the size of kinetic mixing both in field theory and in string theory, and argue that appreciable kinetic mixing is a generic feature of string models. We conclude that the possibility of kinetic mixing effects cannot be ignored in model building and in phenomenological studies of the low-energy SUSY spectra. (orig.)

Generalized Slavnov-Taylor, BRST and covariance identities from the geometry of the gauge surface. (corrigendum)

International Nuclear Information System (INIS)

Jarvis, P.D.; Thompson, G.

1987-04-01

We establish the equivalence between the extended BRST invariances, and the conventional Slavnov-Taylor transformations together with a new ''dual'' analogue. However, the latter (a non-local gauge transformation, generating an A-dependent translation of the gauge-fixing surface) is not an invariance of the Faddeev-Popov determinant, contrary to the published claim. (author)

Some observations on interpolating gauges and non-covariant gauges

Indian Academy of Sciences (India)

We discuss the viability of using interpolating gauges to define the non-covariant gauges starting from the covariant ones. We draw attention to the need for a very careful treatment of boundary condition defining term. We show that the boundary condition needed to maintain gauge-invariance as the interpolating parameter ...

On the hyperbolicity of Einstein's and other gauge field equations

International Nuclear Information System (INIS)

Friedrich, H.

1985-01-01

It is shown that Einstein's vacuum field equations (respectively the conformal vacuum field equations) in a frame formalism imply a symmetric hyperbolic system of ''reduce'' propagation equations for any choice of coordinate system and frame field (and conformal factor). Certain freely specifiable ''gauge source'' functions occurring in the reduced equations reflect the choice of gauge. Together with the initial data they determine the gauge uniquely. Their choice does not affect the isometry class (conformal class) of a solution of an initial value problem. By the same method symmetric hyperbolic propagation equations are obtained from other gauge field equations, irrespective of the gauge. Using the concept of source functions one finds that Einstein's field equation, considered as second order equations for the metric coefficients, are of wave equation type in any coordinate system. (orig.)

Gauge invariance over a group as the first principle of interacting string dynamics

International Nuclear Information System (INIS)

Gervais, J.L.

1986-01-01

It is stressed that the basic principle of the standard gauge theories is the invariance under internal symmetry transformations that do not commute with translations. This concept is generalized to the case where the translation group is replaced by an arbitrarily given non-abelian group G. The generalized Yang-Mills theory, called gauge theory over G, is an attractive extension of the standard formalism. The gauge theory over the conformal group is proposed as the fundamental theory of bosonic strings. As is usual in gauge theories, the interaction is uniquely specific by the invariance properties. For strings, overlap conditions between string positions come out in a natural way. The powerful machinery of Yang-Mills theories is fully applicable to the gauge theories over groups. In particular, an example of the Higgs-Kibble mechanism is given. (orig.)

Spin Gauge Theory of Gravity in Clifford Space

International Nuclear Information System (INIS)

Pavsic, Matej

2006-01-01

A theory in which 16-dimensional curved Clifford space (C-space) provides a realization of Kaluza-Klein theory is investigated. No extra dimensions of spacetime are needed: 'extra dimensions' are in C-space. We explore the spin gauge theory in C-space and show that the generalized spin connection contains the usual 4-dimensional gravity and Yang-Mills fields of the U(1) x SU(2) x SU(3) gauge group. The representation space for the latter group is provided by 16-component generalized spinors composed of four usual 4-component spinors, defined geometrically as the members of four independent minimal left ideals of Clifford algebra

Theory and application of a gauge invariant effective action to the multi-loop renormalization of non-Abelian gauge theories

International Nuclear Information System (INIS)

Hart, C.F.

1981-01-01

A gauge invariant effective action which generalizes the usual background field method is applied to quantum non-Abelian gauge theories. The gauge properties of the theory as well as its equivalence to the conventional theory are presented. Solutions to the new effective field equations are found to be physical and it is shown how S-matrix elements may be computed in terms of this new effective action. Feynman rules are given and the renormalization theory is discussed using minimal subtraction and dimensional regularization. The resulting computation of counterterms is found to be simpler than that of the usual method. A complete two-loop calculation of the β function for pure Yang-Mills theory is given as a specific example of this approach

Dark matter annihilations into two light fermions and one gauge boson. General analysis and antiproton constraints

International Nuclear Information System (INIS)

Garny, Mathias; Ibarra, Alejandro; Vogl, Stefan

2011-12-01

We study in this paper the scenario where the dark matter is constituted by Majo- rana particles which couple to a light Standard Model fermion and an extra scalar via a Yukawa coupling. In this scenario, the annihilation rate into the light fermions with the mediation of the scalar particle is strongly suppressed by the mass of the fermion. Nevertheless, the helicity suppression is lifted by the associated emission of a gauge boson, yielding annihilation rates which could be large enough to allow the indirect detection of the dark matter particles. We perform a general analysis of this scenario, calculating the annihilation cross section of the processes χχ → f anti fV when the dark matter particle is a SU(2) L singlet or doublet, f is a lepton or a quark, and V is a photon, a weak gauge boson or a gluon. We point out that the annihilation rate is particularly enhanced when the dark matter particle is degenerate in mass to the intermediate scalar particle, which is a scenario barely constrained by collider searches of exotic charged or colored particles. Lastly, we derive upper limits on the relevant cross sections from the non-observation of an excess in the cosmic antiproton-to-proton ratio measured by PAMELA. (orig.)

Dark matter annihilations into two light fermions and one gauge boson. General analysis and antiproton constraints

Energy Technology Data Exchange (ETDEWEB)

Garny, Mathias [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Ibarra, Alejandro; Vogl, Stefan [Technische Univ. Muenchen, Garching (Germany). Physik-Department

2011-12-15

We study in this paper the scenario where the dark matter is constituted by Majo- rana particles which couple to a light Standard Model fermion and an extra scalar via a Yukawa coupling. In this scenario, the annihilation rate into the light fermions with the mediation of the scalar particle is strongly suppressed by the mass of the fermion. Nevertheless, the helicity suppression is lifted by the associated emission of a gauge boson, yielding annihilation rates which could be large enough to allow the indirect detection of the dark matter particles. We perform a general analysis of this scenario, calculating the annihilation cross section of the processes {chi}{chi} {yields} f anti fV when the dark matter particle is a SU(2){sub L} singlet or doublet, f is a lepton or a quark, and V is a photon, a weak gauge boson or a gluon. We point out that the annihilation rate is particularly enhanced when the dark matter particle is degenerate in mass to the intermediate scalar particle, which is a scenario barely constrained by collider searches of exotic charged or colored particles. Lastly, we derive upper limits on the relevant cross sections from the non-observation of an excess in the cosmic antiproton-to-proton ratio measured by PAMELA. (orig.)

Inflation and gauge mediation in supersymmetric gauge theory

International Nuclear Information System (INIS)

Nakai, Yuichiro; Sakai, Manabu

2011-01-01

We propose a simple high-scale inflationary scenario based on a phenomenologically viable model with direct gauge mediation of low-scale supersymmetry breaking. Hybrid inflation occurs in a hidden supersymmetry breaking sector. Two hierarchical mass scales to reconcile both high-scale inflation and gauge mediation are necessary for the stability of the metastable supersymmetry breaking vacuum. Our scenario is also natural in light of the Landau pole problem of direct gauge mediation. (author)

Gauge symmetry breaking

International Nuclear Information System (INIS)

Weinberg, S.

1976-01-01

The problem of how gauge symmetries of the weak interactions get broken is discussed. Some reasons why such a heirarchy of gauge symmetry breaking is needed, the reason gauge heirarchies do not seem to arise in theories of a given and related type, and the implications of theories with dynamical symmetry breaking, which can exhibit a gauge hierarchy

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

International Nuclear Information System (INIS)

Jiang Qingquan; Wu Shuangqing

2007-01-01

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

Gravitation SL(2,C) gauge theory and conservation laws

CERN Document Server

Carmeli, Moshe; Nissani, Noah

1990-01-01

This monograph gives a comprehensive presentation of the SL(2,C) Gauge Theory of Gravitation along with some recent developments in the problem of Conservation Laws in General Relativity. Emphasis is put on quadratic Lagrangians which yield the Einstein field equations, as compared with Hilbert's original linear Langrangian, thus gravitation follows the other Gauge Fields all of which are derived from nonlinear Lagrangians.

Solution of the gauge identities in the axial gauge

International Nuclear Information System (INIS)

Delbourgo, R.

1981-01-01

Starting from the spectral representation of the two-point functions in the axial gauge, the gauge identities are solved so as to express the higher-point Green functions linearly in terms of the two-point spectral function. The four-point functions are an important input for investigations of scalar electrodynamics and vector chromodynamics based on the gauge technique. (author)

The current status of nucleonic gauge activity in China

International Nuclear Information System (INIS)

Liye Zhou

2000-01-01

The nucleonic gauge technology in China is in full development. The nucleonic gauges are widely used, mainly in metallurgy, coal, cement and rubber industries. The simple first generation of nucleonic gauge is locally designed and manufactured in industrial scale by many institutions and enterprises. The local market is large and far from being saturated. The quality and reliability of nucleonic gauges and their integration into the control system are still concern. Research and development is going on to improve the quality and to design and produce second generation of multibeam and multienergy nucleonic gauges. (author)

Novel symmetries in Weyl-invariant gravity with massive gauge field

Energy Technology Data Exchange (ETDEWEB)

Abhinav, K. [S.N. Bose National Centre for Basic Sciences, Salt Lake, Kolkata (India); Shukla, A.; Panigrahi, P.K. [Indian Institute of Science Education and Research Kolkata, Mohanpur (India)

2016-11-15

The background field method is used to linearize the Weyl-invariant scalar-tensor gravity, coupled with a Stueckelberg field. For a generic background metric, this action is found not to be invariant, under both a diffeomorphism and generalized Weyl symmetry, the latter being a combination of gauge and Weyl transformations. Interestingly, the quadratic Lagrangian, emerging from a background of Minkowski metric, respects both transformations independently. The Becchi-Rouet-Stora-Tyutin symmetry of scalar-tensor gravity coupled with a Stueckelberg-like massive gauge particle, possessing a diffeomorphism and generalized Weyl symmetry, reveals that in both cases negative-norm states with unphysical degrees of freedom do exist. We then show that, by combining diffeomorphism and generalized Weyl symmetries, all the ghost states decouple, thereby removing the unphysical redundancies of the theory. During this process, the scalar field does not represent any dynamic mode, yet modifies the usual harmonic gauge condition through non-minimal coupling with gravity. (orig.)

Vacuum-assisted breast biopsy: A comparison of 11-gauge and 8-gauge needles in benign breast disease

Directory of Open Access Journals (Sweden)

Kraemer Bernhard

2008-05-01

Full Text Available Abstract Background Minimal invasive breast biopsy is standard care for the diagnosis of suspicious breast lesions. There are different vacuum biopsy (VB systems in use. The aim of the study was to determine the differences between the 8-gauge and the 11-gauge needle with respect to a diagnostic reliability, b complication rate and c subjective perception of pain when used for vacuum-assisted breast biopsy. Methods Between 01/2000 and 09/2004, 923 patients at St. Josefs-Hospital Wiesbaden underwent VB using the Mammotome® (Ethicon Endosurgery, Hamburg. Depending on preoperative detection, the procedure was performed under sonographic or mammographic guidance under local anaesthesia. All patients included in the study were followed up both clinically and using imaging techniques one week after the VB and a second time after a median of 41 months. Excisional biopsy on the ipsilateral breast was an exclusion criteria. Subjective pain scores were recorded on a scale of 0 – 10 (0 = no pain, 10 = unbearable pain. The mean age of the patients was 53 years (30 – 88. Results 123 patients were included in the study in total. 48 patients were biopsied with the 8-gauge needle and 75 with the 11-gauge needle. The use of the 8-gauge needle did not show any significant differences to the 11-gauge needle with regard to diagnostic reliability, complication rate and subjective perception of pain. Conclusion Our data show that there are no relevant differences between the 8-gauge and 11-gauge needle when used for VB. Under sonographic guidance, the use of the 8-gauge needle is recommended for firm breast tissue due to its sharp scalpel point and especially for complete removal of benign lesions. We did not find any advantages in the use of the larger 8-gauge needle compared to the 11-gauge needle in the mammography setting. The utilisation costs of the 8-gauge needle are somewhat higher.

Scalar-vector unitarity mixing in ξ gauge

International Nuclear Information System (INIS)

Kaloshin, A.E.; Radzhabov, A.E.

2003-01-01

The effect of unitary mixing of scalar and vector fields in general ξ gauge is studied. This effect takes place for nonconserved vector currents and ξ gauge generates some additional problems with unphysical scalar field. Solutions of Dyson-Schwinger equations and performed the renormalization of full propagators are obtained. The key feature of renormalization is the usage of Ward identity which relates some different Green functions. It is found that using of Ward identity leads to disappearing of ξ dependence in renormalization matrix element [ru

Elastic Gauge Fields in Weyl Semimetals

Science.gov (United States)

Cortijo, Alberto; Ferreiros, Yago; Landsteiner, Karl; Hernandez Vozmediano, Maria Angeles

We show that, as it happens in graphene, elastic deformations couple to the electronic degrees of freedom as pseudo gauge fields in Weyl semimetals. We derive the form of the elastic gauge fields in a tight-binding model hosting Weyl nodes and see that this vector electron-phonon coupling is chiral, providing an example of axial gauge fields in three dimensions. As an example of the new response functions that arise associated to these elastic gauge fields, we derive a non-zero phonon Hall viscosity for the neutral system at zero temperature. The axial nature of the fields provides a test of the chiral anomaly in high energy with three axial vector couplings. European Union structural funds and the Comunidad de Madrid MAD2D-CM Program (S2013/MIT-3007).

Lattice gauge theory

International Nuclear Information System (INIS)

Mack, G.

1982-01-01

After a description of a pure Yang-Mills theory on a lattice, the author considers a three-dimensional pure U(1) lattice gauge theory. Thereafter he discusses the exact relation between lattice gauge theories with the gauge groups SU(2) and SO(3). Finally he presents Monte Carlo data on phase transitions in SU(2) and SO(3) lattice gauge models. (HSI)

Gauge symmetry breaking in gauge theories -- in search of clarification

NARCIS (Netherlands)

Friederich, Simon

2013-01-01

The paper investigates the spontaneous breaking of gauge symmetries in gauge theories from a philosophical angle, taking into account the fact that the notion of a spontaneously broken local gauge symmetry, though widely employed in textbook expositions of the Higgs mechanism, is not supported by

Atomic quantum simulation of the lattice gauge-Higgs model: Higgs couplings and emergence of exact local gauge symmetry.

Science.gov (United States)

Kasamatsu, Kenichi; Ichinose, Ikuo; Matsui, Tetsuo

2013-09-13

Recently, the possibility of quantum simulation of dynamical gauge fields was pointed out by using a system of cold atoms trapped on each link in an optical lattice. However, to implement exact local gauge invariance, fine-tuning the interaction parameters among atoms is necessary. In the present Letter, we study the effect of violation of the U(1) local gauge invariance by relaxing the fine-tuning of the parameters and showing that a wide variety of cold atoms is still a faithful quantum simulator for a U(1) gauge-Higgs model containing a Higgs field sitting on sites. The clarification of the dynamics of this gauge-Higgs model sheds some light upon various unsolved problems, including the inflation process of the early Universe. We study the phase structure of this model by Monte Carlo simulation and also discuss the atomic characteristics of the Higgs phase in each simulator.

Gauge field theories an introduction with applications

CERN Document Server

Guidry, Mike

1991-01-01

Acquaints readers with the main concepts and literature of elementary particle physics and quantum field theory. In particular, the book is concerned with the elaboration of gauge field theories in nuclear physics; the possibility of creating fundamental new states of matter such as an extended quark-gluon plasma in ultra-relativistic heavy ion collisions; and the relation of gauge theories to the creation and evolution of the universe. Divided into three parts, it opens with an introduction to the general principles of relativistic quantum field theory followed by the essential ingredients of gauge fields for weak and electromagnetic interactions, quantum chromodynamics and strong interactions. The third part is concerned with the interface between modern elementary particle physics and "applied disciplines" such as nuclear physics, astrophysics and cosmology. Includes references and numerous exercises

Unified models of interactions with gauge-invariant variables

International Nuclear Information System (INIS)

Zet, Gheorghe

2000-01-01

A model of gauge theory is formulated in terms of gauge-invariant variables over a 4-dimensional space-time. Namely, we define a metric tensor g μν ( μ , ν = 0,1,2,3) starting with the components F μν a and F μν a tilde of the tensor associated to the Yang-Mills fields and its dual: g μν = 1/(3Δ 1/3 ) (ε abc F μα a F αβ b tilde F βν c ). Here Δ is a scale factor which can be chosen of a convenient form so that the theory may be self-dual or not. The components g μν are interpreted as new gauge-invariant variables. The model is applied to the case when the gauge group is SU(2). For the space-time we choose two different manifolds: (i) the space-time is R x S 3 , where R is the real line and S 3 is the three-dimensional sphere; (ii) the space-time is endowed with axial symmetry. We calculate the components g μν of the new metric for the two cases in terms of SU(2) gauge potentials. Imposing the supplementary condition that the new metric coincides with the initial metric of the space-time, we obtain the field equations (of the first order in derivatives) for the gauge fields. In addition, we determine the scale factor Δ which is introduced in the definition of g μν to ensure the property of self-duality for our SU(2) gauge theory, namely, 1/(2√g)(ε αβστ g μα g νβ F στ a = F μν a , g = det (g μν ). In the case (i) we show that the space-time R x S 3 is not compatible with a self-dual SU(2) gauge theory, but in the case (ii) the condition of self-duality is satisfied. The model developed in our work can be considered as a possible way to unification of general relativity and Yang-Mills theories. This means that the gauge theory can be formulated in the close analogy with the general relativity, i.e. the Yang-Mills equations are equivalent to Einstein equations with the right-hand side of a simple form. (authors)

One-loop renormalization of Lee-Wick gauge theory

International Nuclear Information System (INIS)

Grinstein, Benjamin; O'Connell, Donal

2008-01-01

We examine the renormalization of Lee-Wick gauge theory to one-loop order. We show that only knowledge of the wave function renormalization is necessary to determine the running couplings, anomalous dimensions, and vector boson masses. In particular, the logarithmic running of the Lee-Wick vector boson mass is exactly related to the running of the coupling. In the case of an asymptotically free theory, the vector boson mass runs to infinity in the ultraviolet. Thus, the UV fixed point of the pure gauge theory is an ordinary quantum field theory. We find that the coupling runs more quickly in Lee-Wick gauge theory than in ordinary gauge theory, so the Lee-Wick standard model does not naturally unify at any scale. Finally, we present results on the beta function of more general theories containing dimension six operators which differ from previous results in the literature.

Geometro-stochastic quantization of gauge fields in curved space-time

International Nuclear Information System (INIS)

Prugovecki, E.

1988-01-01

It is shown that the geometro-stochastic method of quantization of massive fields in curved space-time can be extended to the massless cases of electromagnetic fields and general Yang-Mills fields. The Fock fibres of the massive case are replaced in the present context by fibres with indefinite inner products, such as Gupta-Bleuler fibres in the electromagnetic case. The quantum space-time form factor used in the massive case gives rise in the present case to quantum gauge frames whose elements are generalized coherent states corresponding to pseudounitary spin-one representations of direct products of the Poincare group with the U(1), SU(N) or other internal gauge groups. Quantum connections are introduced on bundles of second-quantized frames, and the corresponding parallel transport is expressed in terms of path integrals for quantum frame propagators. In the Yang-Mills case, these path integral make use of Faddeev-Popov quantum frames. It is shown, however, that in the present framework the ghost fields that give rise to these frames possess a geometric interpretation related to the presence of a super-gauge group that, in addition to the external Poincare and Yang-Mills gauge degrees of freedom, involves also the internal ones related to choices of gauge bases within the quantum fibres

On spontaneous parity breaking in three-dimensional gauge-Higgs systems

International Nuclear Information System (INIS)

Ambjoern, J.; Farakos, K.; Shaposhnikov, M.E.

1991-04-01

We address the question of spontaneous breaking of parity in three-dimensional euclidian SU(2) gauge-Higgs theory by Monte Carlo simulations. We observe no sign of spontaneous parity breaking in the behaviour of local gauge invariant operators. However, the presence of parity odd terms in the action can induce a phase transition to a parity odd ground state. (orig.)

Effective potential for spontaneously broken gauge theories and gauge hierarchies

International Nuclear Information System (INIS)

Hagiwara, T.; Ovrut, B.

1979-01-01

The Appelquist-Carazzone effective-field-theory method, where one uses effective light-field coupling constants dependent on the heavy-field sector, is explicitly shown to be valid for the discussion of the gauge-hierarchy problem in grand unified gauge models. Using the method of functionals we derive an expression for the one-loop approximation to the scalar-field effective potential for spontaneously broken theories in an arbitrary R/sub xi/ gauge. We argue that this potential generates, through its derivatives, valid zero-momentum, one-particle-irreducible vertices for any value of xi (not just the xi→infinity Landau gauge). The equation that the one-loop vacuum correction must satisfy is presented, and we solve this equation for a number of spontaneously broken theories including gauge theories with gauge groups U(1) and SO(3). We find that a one-loop vacuum shift in a massless, non-Goldstone direction occurs via the Coleman-Weinberg mechanism with an effective coupling constant dependent on the heavy-field sector

Reducing the rank of gauge groups in orbifold compactification

International Nuclear Information System (INIS)

Sato, H.

1989-01-01

The Wilson-line mechanism in orbifold compactification is investigated for both Abelian and non-Abelian embedding of the Z 3 group in the E 8 x E 8 . The authors give general argument in the fermionic formulation for the gauge degrees of freedom and show that the rank of the gauge group is reduced by introducing nondiagonal Wilson-line matrix in the fermionic boundary conditions

Gauge invariance and equations of motion for closed string modes

Directory of Open Access Journals (Sweden)

B. Sathiapalan

2014-12-01

Full Text Available We continue earlier discussions on loop variables and the exact renormalization group on the string world sheet for closed and open string backgrounds. The world sheet action with a UV regulator is written in a generally background covariant way by introducing a background metric. It is shown that the renormalization group gives background covariant equations of motion – this is the gauge invariance of the graviton. Interaction is written in terms of gauge invariant and generally covariant field strength tensors. The basic idea is to work in Riemann normal coordinates and covariantize the final equation. It turns out that the equations for massive modes are gauge invariant only if the space–time curvature of the (arbitrary background is zero. The exact RG equations give quadratic equations of motion for all the modes including the physical graviton. The level (2,2¯ massive field equations are used to illustrate the techniques. At this level there are mixed symmetry tensors. Gauge invariant interacting equations can be written down. In flat space an action can also be written for the free theory.

Extended monopoles in gauge field theories

International Nuclear Information System (INIS)

Horvath, Z.; Palla, L.

1977-04-01

The paper gives a review of the 't Hooft monopole and briefly discusses the general topological considerations connected with monopoles. A method is presented for constructing explicit monopole solutions in any gauge theory. Some stability questions and time-dependent problems are also considered

Blockspin and multigrid for staggered fermions in non-abelian gauge fields

International Nuclear Information System (INIS)

Kalkreuter, T.; Mack, G.; Speh, M.

1991-07-01

We discuss blockspins for staggered fermions, i.e. averaging and interpolation procedures which are needed in a real space renormalization group approach to gauge theories with staggered fermions and in a multigrid approach to the computation of gauge covariant propagators. The discussion starts from the requirement that the symmetries of the free action should be preserved by the blocking procedure in the limit of a pure gauge. A definition of an averaging kernel as a solution of a gauge covariant eigenvalue equation is proposed, and the properties of a corresponding interpolation kernel are examined in the light of general criteria for good choices of blockspins. Some results of multigrid computation of bosonic propagation in an SU(2) gauge field in 4 dimensions are also presented. (orig.)

Hopf-algebraic renormalization of QED in the linear covariant gauge

Energy Technology Data Exchange (ETDEWEB)

Kißler, Henry, E-mail: kissler@physik.hu-berlin.de

2016-09-15

In the context of massless quantum electrodynamics (QED) with a linear covariant gauge fixing, the connection between the counterterm and the Hopf-algebraic approach to renormalization is examined. The coproduct formula of Green’s functions contains two invariant charges, which give rise to different renormalization group functions. All formulas are tested by explicit computations to third loop order. The possibility of a finite electron self-energy by fixing a generalized linear covariant gauge is discussed. An analysis of subdivergences leads to the conclusion that such a gauge only exists in quenched QED.

Gauge equivalence of σ models with non-compact Grassmannian manifolds

International Nuclear Information System (INIS)

Kundu, A.

1986-01-01

The gauge equivalence (GE) of σ models associated with non-compact Grassmannian manifolds is investigated with emphasis on the necessary restrictions for the choice of gauge elements in such cases. The importance of GE in solving a non-linear system with the help of inverse scattering data of its gauge related counterpart is demonstrated. The gauge relations between generalised Landau-Lifshitz (LL) and non-linear Schroedinger (NLS) type equations and also between non-linear σ models and generalised 'sine-sinh-Gordon' equations for non-compact SU(p,q)/S(U(u,v) x U(s,t)) manifolds are established. Using H-gauge invariance of LL the GE is extended to some higher-order specific non-linear systems. The gauge connection among various LL and NLS equations are schematically represented. Along with the recovery of earlier results important new results, some with significant non-compact structures, are discovered. (author)

Fundamental problems of gauge field theory

International Nuclear Information System (INIS)

Velo, G.; Wightman, A.S.

1986-01-01

As a result of the experimental and theoretical developments of the last two decades, gauge field theory, in one form or another, now provides the standard language for the description of Nature; QCD and the standard model of the electroweak interactions illustrate this point. It is a basic task of mathematical physics to provide a solid foundation for these developments by putting the theory in a physically transparent and mathematically rigorous form. The lecture notes collected in this volume concentrate on the many unsolved problems which arise here, and on the general ideas and methods which have been proposed for their solution. In particular, the use of rigorous renormalization group methods to obtain control over the continuum limit of lattice gauge field theories, the exploration of the extraordinary enigmatic connections between Kac-Moody-Virasoro algebras and string theory, and the systematic use of the theory of local algebras and indefinite metric spaces to classify the charged C* states in gauge field theories are mentioned

The gauge-independent QCD effective charge

International Nuclear Information System (INIS)

Watson, N.J.

1999-01-01

It is shown how the QCD concept of a gauge-, scale-and scheme-independent one-loop effective charge can be extended directly at the diagrammatic level to QCD, thus justifying explicitly the 'naive non-abelialization' prescription used in renormalon calculus. It is first argued that, for one-shell external fields and at the strictly one-loop level, the required gluon self-energy-like function is precisely that obtained from S-matrix elements via the pinch technique. The generalization of the pinch technique to explicitly off-shell processes is then introduced. It is shown how, as a result of a fundamental cancellation among conventional perturbation theory diagrams encoded in the QCD Ward identities, the pinch technique one-loop gluon self-energy iΠ μν ab (q) remains gauge-independent and universal regardless of the fact that the 'external' fields in the given process are off-shell. This demonstration involves a simple technique enabling the isolation in a arbitrary gauge, of iΠ μν ab (q) from subclasses of up to several hundreds diagrams at once. Furthermore, it is shown how this one-loop cancellation mechanism iterates for the subclasses of n-loop diagrams containing implicitly the Dyson chains of n-loop self energies iΠ μν ab (q). The gauge cancellation required for the Dyson summation of iΠ μν ab (q) is thus demonstrated explicitly in the class of ghost-free gauges for all orders n. (authors)

Space-time and Local Gauge Symmetries

Indian Academy of Sciences (India)

Home; Journals; Resonance – Journal of Science Education; Volume 6; Issue 2. Symmetries of Particle Physics: Space-time and Local Gauge Symmetries. Sourendu Gupta. General Article Volume 6 Issue 2 February 2001 pp 29-38. Fulltext. Click here to view fulltext PDF. Permanent link:

Enhanced symmetries of gauge theory and resolving the spectrum of local operators

International Nuclear Information System (INIS)

Kimura, Yusuke; Ramgoolam, Sanjaye

2008-01-01

Enhanced global non-Abelian symmetries at zero coupling in Yang Mills theory play an important role in diagonalizing the two-point functions of multimatrix operators. Generalized Casimirs constructed from the iterated commutator action of these enhanced symmetries resolve all the multiplicity labels of the bases of matrix operators which diagonalize the two-point function. For the case of U(N) gauge theory with a single complex matrix in the adjoint of the gauge group we have a U(N) x4 global symmetry of the scaling operator at zero coupling. Different choices of commuting sets of Casimirs, for the case of a complex matrix, lead to the restricted Schur basis previously studied in connection with string excitations of giant gravitons and the Brauer basis studied in connection with brane-antibrane systems. More generally these remarks can be extended to the diagonalization for any global symmetry group G. Schur-Weyl duality plays a central role in connecting the enhanced symmetries and the diagonal bases.

Gauge field models

International Nuclear Information System (INIS)

Becchi, C.; Rouet, A.; Stora, R.

1975-10-01

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

Hermiticity and gauge invariance

International Nuclear Information System (INIS)

Treder, H.J.

1987-01-01

In the Theory of Hermitian Relativity (HRT) the postulates of hermiticity and gauge invariance are formulated in different ways, due to a different understanding of the idea of hermiticity. However all hermitian systems of equations have to satisfy Einstein's weak system of equations being equivalent to Einstein-Schroedinger equations. (author)

Infrared behavior of gluons and ghosts in ghost-antighost symmetric gauges

International Nuclear Information System (INIS)

Alkofer, R.; Fischer, C.S.; Reinhardt, H.; Smekal, L. von

2003-01-01

To investigate the possibility of a ghost-antighost condensate, the coupled Dyson-Schwinger equations for the gluon and ghost propagators in Yang-Mills theories are derived in general covariant gauges, including ghost-antighost symmetric gauges. The infrared behavior of these two-point functions is studied in a bare-vertex truncation scheme which has proven to be successful in the Landau gauge. In all linear covariant gauges the same infrared behavior as in the Landau gauge is found: The gluon propagator is infrared-suppressed whereas the ghost propagator is infrared-enhanced. This infrared singular behavior provides an indication against a ghost-antighost condensate. In the ghost-antighost symmetric gauges we find that the infrared behavior of the gluon and ghost propagators cannot be determined when replacing all dressed vertices by bare ones. The question of a BRS invariant dimension-2 condensate remains to be further studied

Zero energy gauge fields and the phases of a gauge theory

International Nuclear Information System (INIS)

Guendelman, E.I.

1990-01-01

A new approach to the definition of the phases of a Poincare invariant gauge theory is developed. It is based on the role of gauge transformations that change the asymptotic value of the gauge fields from zero to a constant. In the context of theories without Higgs fields, this symmetry can be spontaneously broken when the gauge fields are massless particles, explicitly broken when the gauge fields develop a mass. Finally, the vacuum can be invariant under this transformation, this last case can be achieved when the theory has a violent infrared behavior, which in some theories can be connected to a confinement mechanism

Gauge fixing conditions for the SU(3) gauge theory

International Nuclear Information System (INIS)

Ragiadakos, Ch.; Viswanathan, K.S.

1979-01-01

SU(3) gauge theory is quantized in the temporal gauge A 0 =0. Gauge fixing conditions are imposed completely on the electric field components, conjugate to the vector potential Ssub(i) that belongs to the subalgebra SO(3) of SU(3). The generating functional in terms of the independent variables is derived. It is ghost-free and may be regarded as a theory of (non-relativistic) spin-0, 1, 2, and 3 fields. (Auth.)

Gauge invariance and the quark-antiquark static potential

International Nuclear Information System (INIS)

Cahill, K.; Stump, D.R.

1979-01-01

We calculate the quark-antiquark static potential to order g 4 in temporal-gauge quantum chromodynamics by constructing a suitably general family of gauge-invariant qq-bar states and then selecting the one whose energy is minimal for a given qq-bar separation r. Our results agree with those of conventional perturbation theory. We study various ways in which quark confinement might arise from nonperturbative effects related to the Gribov ambiguity. We find that the presence of long-range gauge fields can change the asymptotic behavior of the Coulomb Green's function from r -1 to r/sup -1/2/. We illustrate this possibility by a simple example. After making some simplifying assumptions, we obtain a minimally confining potential V (r) that rises logarithmically for large r

A non-perturbative study of massive gauge theories

DEFF Research Database (Denmark)

Della Morte, Michele; Hernandez, Pilar

2013-01-01

and the lightest degrees of freedom are spin one vector particles with the same quantum numbers as the conserved current, we argue that the most general effective theory describing their low-energy dynamics must be a massive gauge theory. We present results of a exploratory numerical simulation of the model......We consider a non-perturbative formulation of an SU(2) massive gauge theory on a space-time lattice, which is also a discretised gauged non-linear chiral model. The lattice model is shown to have an exactly conserved global SU(2) symmetry. If a scaling region for the lattice model exists...... and find indications for the presence of a scaling region where both a triplet vector and a scalar remain light....

Residual gauge invariance of Hamiltonian lattice gauge theories

International Nuclear Information System (INIS)

Ryang, S.; Saito, T.; Shigemoto, K.

1984-01-01

The time-independent residual gauge invariance of Hamiltonian lattice gauge theories is considered. Eigenvalues and eigenfunctions of the unperturbed Hamiltonian are found in terms of Gegengauer's polynomials. Physical states which satisfy the subsidiary condition corresponding to Gauss' law are constructed systematically. (orig.)

Propagators for gauge-invariant observables in cosmology

Science.gov (United States)

Fröb, Markus B.; Lima, William C. C.

2018-05-01

We make a proposal for gauge-invariant observables in perturbative quantum gravity in cosmological spacetimes, building on the recent work of Brunetti et al (2016 J. High Energy Phys. JHEP08(2016)032). These observables are relational, and are obtained by evaluating the field operator in a field-dependent coordinate system. We show that it is possible to define this coordinate system such that the non-localities inherent in any higher-order observable in quantum gravity are causal, i.e. the value of the gauge-invariant observable at a point x only depends on the metric and inflation perturbations in the past light cone of x. We then construct propagators for the metric and inflaton perturbations in a gauge adapted to that coordinate system, which simplifies the calculation of loop corrections, and give explicit expressions for relevant cases: matter- and radiation-dominated eras and slow-roll inflation.

Abelian gauge symmetries in F-theory and dual theories

Science.gov (United States)

Song, Peng

In this dissertation, we focus on important physical and mathematical aspects, especially abelian gauge symmetries, of F-theory compactifications and its dual formulations within type IIB and heterotic string theory. F-theory is a non-perturbative formulation of type IIB string theory which enjoys important dualities with other string theories such as M-theory and E8 x E8 heterotic string theory. One of the main strengths of F-theory is its geometrization of many physical problems in the dual string theories. In particular, its study requires a lot of mathematical tools such as advanced techniques in algebraic geometry. Thus, it has also received a lot of interests among mathematicians, and is a vivid area of research within both the physics and the mathematics community. Although F-theory has been a long-standing theory, abelian gauge symmetry in Ftheory has been rarely studied, until recently. Within the mathematics community, in 2009, Grassi and Perduca first discovered the possibility of constructing elliptically fibered varieties with non-trivial toric Mordell-Weil group. In the physics community, in 2012, Morrison and Park first made a major advancement by constructing general F-theory compactifications with U(1) abelian gauge symmetry. They found that in such cases, the elliptically-fibered Calabi-Yau manifold that F-theory needs to be compactified on has its fiber being a generic elliptic curve in the blow-up of the weighted projective space P(1;1;2) at one point. Subsequent developments have been made by Cvetic, Klevers and Piragua extended the works of Morrison and Park and constructed general F-theory compactifications with U(1) x U(1) abelian gauge symmetry. They found that in the U(1) x U(1) abelian gauge symmetry case, the elliptically-fibered Calabi-Yau manifold that F-theory needs to be compactified on has its fiber being a generic elliptic curve in the del Pezzo surface dP2. In chapter 2 of this dissertation, I bring this a step further by

Kaluza–Klein-type models of de Sitter and Poincaré gauge theories of gravity

International Nuclear Information System (INIS)

Lu Jiaan; Huang Chaoguang

2013-01-01

We construct Kaluza–Klein-type models with a de Sitter or Minkowski bundle in the de Sitter or Poincaré gauge theory of gravity, respectively. A manifestly gauge-invariant formalism has been given. The gravitational dynamics is constructed by the geometry of the de Sitter or Minkowski bundle and a global section which plays an important role in the gauge-invariant formalism. Unlike the old Kaluza–Klein-type models of gauge theory of gravity, a suitable cosmological term can be obtained in the Lagrangian of our models and the models in the spin-current-free and torsion-free limit will come back to general relativity with a corresponding cosmological term. We also generalize the results to the case with a variable cosmological term. (paper)

Gauge fixing, BRS invariance and Ward identities for randomly stirred flows

International Nuclear Information System (INIS)

Berera, Arjun; Hochberg, David

2009-01-01

The Galilean invariance of the Navier-Stokes equation is shown to be akin to a global gauge symmetry familiar from quantum field theory. This symmetry leads to a multiple counting of infinitely many inertial reference frames in the path integral approach to randomly stirred fluids. This problem is solved by fixing the gauge, i.e., singling out one reference frame. The gauge fixed theory has an underlying Becchi-Rouet-Stora (BRS) symmetry which leads to the Ward identity relating the exact inverse response and vertex functions. This identification of Galilean invariance as a gauge symmetry is explored in detail, for different gauge choices and by performing a rigorous examination of a discretized version of the theory. The Navier-Stokes equation is also invariant under arbitrary rectilinear frame accelerations, known as extended Galilean invariance (EGI). We gauge fix this extended symmetry and derive the generalized Ward identity that follows from the BRS invariance of the gauge-fixed theory. This new Ward identity reduces to the standard one in the limit of zero acceleration. This gauge-fixing approach unambiguously shows that Galilean invariance and EGI constrain only the zero mode of the vertex but none of the higher wavenumber modes.

Gauge fixing, BRS invariance and Ward identities for randomly stirred flows

Energy Technology Data Exchange (ETDEWEB)

Berera, Arjun [School of Physics and Astronomy, University of Edinburgh, Edinburgh, EH9 3JZ (United Kingdom)], E-mail: ab@ph.ed.ac.uk; Hochberg, David [Centro de Astrobiologia (CSIC-INTA), Ctra. Ajalvir Km. 4, 28850 Torrejon de Ardoz, Madrid (Spain)], E-mail: hochbergd@inta.es

2009-06-21

The Galilean invariance of the Navier-Stokes equation is shown to be akin to a global gauge symmetry familiar from quantum field theory. This symmetry leads to a multiple counting of infinitely many inertial reference frames in the path integral approach to randomly stirred fluids. This problem is solved by fixing the gauge, i.e., singling out one reference frame. The gauge fixed theory has an underlying Becchi-Rouet-Stora (BRS) symmetry which leads to the Ward identity relating the exact inverse response and vertex functions. This identification of Galilean invariance as a gauge symmetry is explored in detail, for different gauge choices and by performing a rigorous examination of a discretized version of the theory. The Navier-Stokes equation is also invariant under arbitrary rectilinear frame accelerations, known as extended Galilean invariance (EGI). We gauge fix this extended symmetry and derive the generalized Ward identity that follows from the BRS invariance of the gauge-fixed theory. This new Ward identity reduces to the standard one in the limit of zero acceleration. This gauge-fixing approach unambiguously shows that Galilean invariance and EGI constrain only the zero mode of the vertex but none of the higher wavenumber modes.

Regularization of the light-cone gauge gluon propagator singularities using sub-gauge conditions

Energy Technology Data Exchange (ETDEWEB)

Chirilli, Giovanni A.; Kovchegov, Yuri V.; Wertepny, Douglas E. [Department of Physics, The Ohio State University,191 W Woodruff Ave, Columbus, OH 43210 (United States)

2015-12-21

Perturbative QCD calculations in the light-cone gauge have long suffered from the ambiguity associated with the regularization of the poles in the gluon propagator. In this work we study sub-gauge conditions within the light-cone gauge corresponding to several known ways of regulating the gluon propagator. Using the functional integral calculation of the gluon propagator, we rederive the known sub-gauge conditions for the θ-function gauges and identify the sub-gauge condition for the principal value (PV) regularization of the gluon propagator’s light-cone poles. The obtained sub-gauge condition for the PV case is further verified by a sample calculation of the classical Yang-Mills field of two collinear ultrarelativistic point color charges. Our method does not allow one to construct a sub-gauge condition corresponding to the well-known Mandelstam-Leibbrandt prescription for regulating the gluon propagator poles.

Gauge theories of the weak interactions

International Nuclear Information System (INIS)

Quinn, H.

1978-08-01

Two lectures are presented on the Weinberg--Salam--Glashow--Iliopoulos--Maiani gauge theory for weak interactions. An attempt is made to give some impressions of the generality of this model, how it was developed, variations found in the literature, and the status of the standard model. 21 references

2 + 1 dimensional de Sitter universe emerging from the gauge structure of a nonlinear quantum system.

Science.gov (United States)

Kam, Chon-Fai; Liu, Ren-Bao

2017-08-29

Berry phases and gauge structures are fundamental quantum phenomena. In linear quantum mechanics the gauge field in parameter space presents monopole singularities where the energy levels become degenerate. In nonlinear quantum mechanics, which is an effective theory of interacting quantum systems, there can be phase transitions and hence critical surfaces in the parameter space. We find that these critical surfaces result in a new type of gauge field singularity, namely, a conic singularity that resembles the big bang of a 2 + 1 dimensional de Sitter universe, with the fundamental frequency of Bogoliubov excitations acting as the cosmic scale, and mode softening at the critical surface, where the fundamental frequency vanishes, causing a causal singularity. Such conic singularity may be observed in various systems such as Bose-Einstein condensates and molecular magnets. This finding offers a new approach to quantum simulation of fundamental physics.

Nonlocal gauge theories

International Nuclear Information System (INIS)

Krasnikov, N.V.

1987-01-01

Nonlocal gauge theories including gravity are considered. It is shown that the introduction of the additional nonlocal interaction makes γ 5 -anomalous theories meaningful. The introduction of such interaction leads to macrocausal unitary theory, which describes the interaction of massive vector fields with fermion fields. It is shown that nonlocal gauge theories with nonlocal scale Λ nl ≤(1-10) TeV can solve the gauge hierarchy problem. An example of nonlinear grand unified gauge model in which topologically nontrivial finite energy monopole solutions are absent is found

Search for new heavy charged gauge bosons

International Nuclear Information System (INIS)

Magass, Carsten Martin

2007-01-01

The TEVATRON proton-antiproton collider at FERMILAB (near Chicago/USA) is operating at a center-of-mass energy of √(s)=1.96 TeV since March 2001. This analysis uses data taken with the DOe detector until February 2006 corresponding to an integrated luminosity of about ∫Ldt=1 fb -1 . Using this dataset, a search for a new heavy charged gauge boson W ' and its subsequent decay into an electron and a neutrino is performed: p anti p→W ' +X→eν+X. Additional gauge bosons (including the equivalent to the Z, the Z ' ) are introduced in many extensions to the Standard Model of particle physics. Assuming the most general case, the new gauge group can comprise a new mixing angle and new couplings. Here, the Altarelli Reference Model is considered which represents a generalization of the Manifest Left-Right Symmetric Model with light right-handed neutrinos. This model makes the assumptions that the new gauge boson W ' has the same couplings as the Standard Model W boson and that there is no mixing. Hence, the W ' is a heavy copy of the Standard Model W boson. The clear decay signature (in analogy to the decay of the W) contains an isolated electron with extreme high energy which is important for triggering. The neutrino can not be detected, but it gives rise to missing energy in the detector. The Jacobian peak in the transverse mass distribution stemming from the W decay is used for calibration, whereas the tail of the transverse mass distribution is searched for a possible W ' signal. The data agrees with the expectation from background processes. For instance, in the data 37 events are reconstructed with transverse masses above 300 GeV compared to a prediction of 37.1±2.1(stat) +6.0 -3.7 (sys) background events. Since no significant excess is found in the data, an upper limit is set on the production cross section for heavy charged gauge bosons decaying into electron and neutrino, σ W ' x Br(W ' →eν). Using this limit, a lower bound on the mass of the new gauge

Entanglement entropy and nonabelian gauge symmetry

International Nuclear Information System (INIS)

Donnelly, William

2014-01-01

Entanglement entropy has proven to be an extremely useful concept in quantum field theory. Gauge theories are of particular interest, but for these systems the entanglement entropy is not clearly defined because the physical Hilbert space does not factor as a tensor product according to regions of space. Here we review a definition of entanglement entropy that applies to abelian and nonabelian lattice gauge theories. This entanglement entropy is obtained by embedding the physical Hilbert space into a product of Hilbert spaces associated to regions with boundary. The latter Hilbert spaces include degrees of freedom on the entangling surface that transform like surface charges under the gauge symmetry. These degrees of freedom are shown to contribute to the entanglement entropy, and the form of this contribution is determined by the gauge symmetry. We test our definition using the example of two-dimensional Yang–Mills theory, and find that it agrees with the thermal entropy in de Sitter space, and with the results of the Euclidean replica trick. We discuss the possible implications of this result for more complicated gauge theories, including quantum gravity. (paper)

The light-cone gauge at two loops: The scalar anomalous dimension

International Nuclear Information System (INIS)

Capper, D.M.; Suzuki, A.T.; Jones, D.R.T.

1985-01-01

We demonstrate that the light-cone gauge is a feasible tool for multi-loop computations by using it to evaluate the two-loop scalar anomalous dimension, γsup((2)), in a general gauge theory. In the special case of supersymmetry we obtain agreement with previous results which were derived using nonlight-cone techniques. (orig.)

URBAN RAIN GAUGE SITING SELECTION BASED ON GIS-MULTICRITERIA ANALYSIS

Directory of Open Access Journals (Sweden)

Y. Fu

2016-06-01

Full Text Available With the increasingly rapid growth of urbanization and climate change, urban rainfall monitoring as well as urban waterlogging has widely been paid attention. In the light of conventional siting selection methods do not take into consideration of geographic surroundings and spatial-temporal scale for the urban rain gauge site selection, this paper primarily aims at finding the appropriate siting selection rules and methods for rain gauge in urban area. Additionally, for optimization gauge location, a spatial decision support system (DSS aided by geographical information system (GIS has been developed. In terms of a series of criteria, the rain gauge optimal site-search problem can be addressed by a multicriteria decision analysis (MCDA. A series of spatial analytical techniques are required for MCDA to identify the prospective sites. With the platform of GIS, using spatial kernel density analysis can reflect the population density; GIS buffer analysis is used to optimize the location with the rain gauge signal transmission character. Experiment results show that the rules and the proposed method are proper for the rain gauge site selection in urban areas, which is significant for the siting selection of urban hydrological facilities and infrastructure, such as water gauge.

Test of gauge invariance and unitarity of the quantized Einstein theory of gravity

International Nuclear Information System (INIS)

Hsu, J.P.; Underwood, J.A.

1975-01-01

Explicit calculations at the 1-loop level verify that the usual quantized Einstein theory of gravity is indeed gauge independent and unitary for all values of the gauge parameter α. This lends nontrivial support to a general formal proof

Canonical Yang-Mills field theory with invariant gauge-families

International Nuclear Information System (INIS)

Yokoyama, Kan-ichi

1978-01-01

A canonical Yang-Mills field theory with indefinite metric is presented on the basis of a covariant gauge formalism for quantum electrodynamics. As the first step of the formulation, a many-gauge-field problem, in which many massless Abelian-gauge fields coexist, is treated from a new standpoint. It is shown that only a single pair of a gaugeon field and its associated one can govern the gauge structure of the whole system. The result obtained is further extended to cases of non-Abelian gauge theories. Gauge parameters for respective components of the Yang-Mills fields are introduced as a group vector. There exists a q-number local gauge transformation which connects relevant fields belonging to the same invariant gauge family with one another in a manifestly covariant way. In canonical quantization, the Faddeev-Popov ghosts are introduced in order to guarantee the existence of a desirable physical subspace with positive semi-definite metric. As to treatment of the Faddeev-Popov ghosts, Kugo and Ojima's approach is adopted. Three supplementary conditions which are consistent with one another constrain the physical subspace. (author)

Non Abelian T-duality in Gauged Linear Sigma Models

Science.gov (United States)

Bizet, Nana Cabo; Martínez-Merino, Aldo; Zayas, Leopoldo A. Pando; Santos-Silva, Roberto

2018-04-01

Abelian T-duality in Gauged Linear Sigma Models (GLSM) forms the basis of the physical understanding of Mirror Symmetry as presented by Hori and Vafa. We consider an alternative formulation of Abelian T-duality on GLSM's as a gauging of a global U(1) symmetry with the addition of appropriate Lagrange multipliers. For GLSMs with Abelian gauge groups and without superpotential we reproduce the dual models introduced by Hori and Vafa. We extend the construction to formulate non-Abelian T-duality on GLSMs with global non-Abelian symmetries. The equations of motion that lead to the dual model are obtained for a general group, they depend in general on semi-chiral superfields; for cases such as SU(2) they depend on twisted chiral superfields. We solve the equations of motion for an SU(2) gauged group with a choice of a particular Lie algebra direction of the vector superfield. This direction covers a non-Abelian sector that can be described by a family of Abelian dualities. The dual model Lagrangian depends on twisted chiral superfields and a twisted superpotential is generated. We explore some non-perturbative aspects by making an Ansatz for the instanton corrections in the dual theories. We verify that the effective potential for the U(1) field strength in a fixed configuration on the original theory matches the one of the dual theory. Imposing restrictions on the vector superfield, more general non-Abelian dual models are obtained. We analyze the dual models via the geometry of their susy vacua.

Gauge-fields and integrated quantum-classical theory

International Nuclear Information System (INIS)

Stapp, H.P.

1986-01-01

Physical situations in which quantum systems communicate continuously to their classically described environment are not covered by contemporary quantum theory, which requires a temporary separation of quantum degrees of freedom from classical ones. A generalization would be needed to cover these situations. An incomplete proposal is advanced for combining the quantum and classical degrees of freedom into a unified objective description. It is based on the use of certain quantum-classical structures of light that arise from gauge invariance to coordinate the quantum and classical degrees of freedom. Also discussed is the question of where experimenters should look to find phenomena pertaining to the quantum-classical connection. 17 refs

Gauge fields in algebraically special space-times

International Nuclear Information System (INIS)

Torres del Castillo, G.F.

1985-01-01

It is shown that in an algebraically special space-time which admits a congruence of null strings, a source-free gauge field aligned with the congruence is determined by a matrix potential which has to satisfy a second-order differential equation with quadratic nonlinearities. The Einstein--Yang--Mills equations are then reduced to a scalar and two matrix equations. In the case of self-dual gauge fields in a self-dual space-time, the existence of an infinite set of conservation laws, of an associated linear system, and of infinitesimal Baecklund transformations is demonstrated. All the results apply for an arbitrary gauge group

Investigation of the dual-gauge principle for eliminating measurement interference in nuclear density and moisture gauges

International Nuclear Information System (INIS)

Dunn, W.L.

1974-07-01

The development of mathematical models for an application of the dual-gauge principle to surface neutron moisture content gauges were made under an Agency co-ordinated research programme. The response of a detector (such as a BF 3 proportional counter) to low-energy neutrons is dependent on the hydrogen present in the sample in the form of water. Other factors which affect the gauge response are sample density, composition (particularly with regard to the presence of strong thermal neutron absorbers), and bound hydrogen content. In this work mathematical models for epicadmium and bare BF 3 detector response have been developed for surface neutron moisture content gauges. These models are based on epithermal and thermal line and area flux models obtained from Diffusion Theory and Transport Theory, where flux as a function of radial distance, r, from the source is phi(r), line flux ∫ phi (r) dr, and area flux is ∫ phi (r)rdr. All models have been checked by calculation and comparison to experimental results except for the Transport Theory thermal flux models. The computer calculations were made on an IBM 370/165 system. In addition, the dual-gauge principle was applied and demonstrated as a means of minimizing the composition measurement interference

Gauge theory and elementary particles

International Nuclear Information System (INIS)

Zwirn, H.

1982-01-01

The present orientation of particle physics, founded on local gauge invariance theories and spontaneous symmetry breaking is described in a simple formalism. The application of these ideas to the latest theories describing electromagnetic and weak interactions (Glashow, Weinberg, Salam models) and strong interactions, quantum chromodynamics, is presented so as to give a general picture of the mechanisms subtending these theories [fr

Monte Carlo analysis of thermal transpiration effects in capacitance diaphragm gauges with helicoidal baffle system

International Nuclear Information System (INIS)

Vargas, M; Stefanov, S; Wüest, M

2012-01-01

The Capacitance Diaphragm Gauge (CDG) is one of the most widely used vacuum gauges in low and middle vacuum ranges. This device consists basically of a very thin ceramic or metal diaphragm which forms one of the electrodes of a cap acitor. The pressure is determined by measuring the variation in the capacitance due to the deflection of the diaphragm caused by the pressure difference established across the membrane. In order to minimize zero drift, some CDGs are operated keeping the sensor at a higher temperature. This difference in the temperature between the sensor and the vacuum chamber makes the behaviour of the gauge non-linear due to thermal transpiration effects. This effect becomes more significant when we move from the transitional flow to the free molecular regime. Besides, CDGs may incorporate different baffle systems to avoid the condensation on the membrane or its contamination. In this work, the thermal transpiration effect on the behaviour of a rarefied gas and on the measurements in a CDG with a helicoidal baffle system is investigated by using the Direct Simulation Monte Carlo method (DSMC). The study covers the behaviour of the system under the whole range of rarefaction, from the continuum up to the free molecular limit and the results are compared with empirical results. Moreover, the influence of the boundary conditions on the thermal transpiration effects is investigated by using Maxwell boundary conditions.

Quantum and classical gauge symmetries

International Nuclear Information System (INIS)

Fujikawa, Kazuo; Terashima, Hiroaki

2001-01-01

The use of the mass term of the gauge field as a gauge fixing term, which was discussed by Zwanziger, Parrinello and Jona-Lasinio in a large mass limit, is related to the non-linear gauge by Dirac and Nambu. We have recently shown that this use of the mass term as a gauge fixing term is in fact identical to the conventional local Faddeev-Popov formula without taking a large mass limit, if one takes into account the variation of the gauge field along the entire gauge orbit. This suggests that the classical massive vector theory, for example, could be re-interpreted as a gauge invariant theory with a gauge fixing term added in suitably quantized theory. As for massive gauge particles, the Higgs mechanics, where the mass term is gauge invariant, has a more intrinsic meaning. We comment on several implications of this observation. (author)

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

Energy Technology Data Exchange (ETDEWEB)

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

2012-09-26

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

Topologically massive gauge theories and their dual factorized gauge-invariant formulation

International Nuclear Information System (INIS)

Bertrand, Bruno; Govaerts, Jan

2007-01-01

There exists a well-known duality between the Maxwell-Chern-Simons theory and the 'self-dual' massive model in (2 + 1) dimensions. This dual description may be extended to topologically massive gauge theories (TMGT) for forms of arbitrary rank and in any dimension. This communication introduces the construction of this type of duality through a reparametrization of the 'master' theory action. The dual action thereby obtained preserves the full gauge symmetry structure of the original theory. Furthermore, the dual action is factorized into a propagating sector of massive gauge-invariant variables and a decoupled sector of gauge-variant variables defining a pure topological field theory. Combining the results obtained within the Lagrangian and Hamiltonian formulations, a completed structure for a gauge-invariant dual factorization of TMGT is thus achieved. (fast track communication)

Microprocessor isotope gauges for measurement of coating thickness and of air dust pollution

International Nuclear Information System (INIS)

Machaj, B.; Zrudelny, F.; Sikora, A.; Jaszczuk, J.

1986-01-01

The article describes a coating thickness gauge based on measurement of backscattered beta particles, and an air dust pollution gauge based on measurement of dust deposited from known volume of ambient air passed through a filter, by attenuation of beta radiation. In both cases to control the gauges and to process head signals microcomputer system based on Intel 8080 microprocessor is employed. Algorithms for processing and control of the gauges and corresponding flow charts are presented. Block diagram of microcomputer system used is presented, as well as the manner of operation of the gauges. (author)

Faddeev-Senjanovic quantization of SU(n) N=2 supersymmetric gauge field system with a non-Abelian Chern-Simons topological term and its fractional spin

International Nuclear Information System (INIS)

Huang Yongchang; Huo Qiuhong

2008-01-01

Using Faddeev-Senjanovic path integral quantization for constrained Hamilton system, we quantize SU(n) N=2 supersymmetric gauge field system with non-Abelian Chern-Simons topological term in 2+1 dimensions. We use consistency of Coulomb gauge condition to naturally deduce a new gauge condition. Furthermore, we obtain the generating functional of Green function in phase space, deduce the angular momentum based on the global canonical Noether theorem at quantum level, obtain the fractional spin of this supersymmetric system, and show that the total angular momentum is the sum of the orbital angular momentum and spin angular momentum of the non-Abelian gauge field. Finally, we obtain the anomalous fractional spin and discover that the fractional spin has the contributions of both the group superscript components and A 0 s (x) charge

Gauge symmetry from decoupling

Directory of Open Access Journals (Sweden)

C. Wetterich

2017-02-01

Full Text Available Gauge symmetries emerge from a redundant description of the effective action for light degrees of freedom after the decoupling of heavy modes. This redundant description avoids the use of explicit constraints in configuration space. For non-linear constraints the gauge symmetries are non-linear. In a quantum field theory setting the gauge symmetries are local and can describe Yang–Mills theories or quantum gravity. We formulate gauge invariant fields that correspond to the non-linear light degrees of freedom. In the context of functional renormalization gauge symmetries can emerge if the flow generates or preserves large mass-like terms for the heavy degrees of freedom. They correspond to a particular form of gauge fixing terms in quantum field theories.

The light-front gauge-invariant energy-momentum tensor

International Nuclear Information System (INIS)

Lorce, Cedric

2015-01-01

In this study, we provide for the first time a complete parametrization for the matrix elements of the generic asymmetric, non-local and gauge-invariant canonical energy-momentum tensor, generalizing therefore former works on the symmetric, local and gauge-invariant kinetic energy-momentum tensor also known as the Belinfante-Rosenfeld energy-momentum tensor. We discuss in detail the various constraints imposed by non-locality, linear and angular momentum conservation. We also derive the relations with two-parton generalized and transverse-momentum dependent distributions, clarifying what can be learned from the latter. In particular, we show explicitly that two-parton transverse-momentum dependent distributions cannot provide any model-independent information about the parton orbital angular momentum. On the way, we recover the Burkardt sum rule and obtain similar new sum rules for higher-twist distributions

A new method for automated dynamic calibration of tipping-bucket rain gauges

Science.gov (United States)

Humphrey, M.D.; Istok, J.D.; Lee, J.Y.; Hevesi, J.A.; Flint, A.L.

1997-01-01

Existing methods for dynamic calibration of tipping-bucket rain gauges (TBRs) can be time consuming and labor intensive. A new automated dynamic calibration system has been developed to calibrate TBRs with minimal effort. The system consists of a programmable pump, datalogger, digital balance, and computer. Calibration is performed in two steps: 1) pump calibration and 2) rain gauge calibration. Pump calibration ensures precise control of water flow rates delivered to the rain gauge funnel; rain gauge calibration ensures precise conversion of bucket tip times to actual rainfall rates. Calibration of the pump and one rain gauge for 10 selected pump rates typically requires about 8 h. Data files generated during rain gauge calibration are used to compute rainfall intensities and amounts from a record of bucket tip times collected in the field. The system was tested using 5 types of commercial TBRs (15.2-, 20.3-, and 30.5-cm diameters; 0.1-, 0.2-, and 1.0-mm resolutions) and using 14 TBRs of a single type (20.3-cm diameter; 0.1-mm resolution). Ten pump rates ranging from 3 to 154 mL min-1 were used to calibrate the TBRs and represented rainfall rates between 6 and 254 mm h-1 depending on the rain gauge diameter. All pump calibration results were very linear with R2 values greater than 0.99. All rain gauges exhibited large nonlinear underestimation errors (between 5% and 29%) that decreased with increasing rain gauge resolution and increased with increasing rainfall rate, especially for rates greater than 50 mm h-1. Calibration curves of bucket tip time against the reciprocal of the true pump rate for all rain gauges also were linear with R2 values of 0.99. Calibration data for the 14 rain gauges of the same type were very similar, as indicated by slope values that were within 14% of each other and ranged from about 367 to 417 s mm h-1. The developed system can calibrate TBRs efficiently, accurately, and virtually unattended and could be modified for use with other

Localizability and local gauge symmetry in quantum theory

International Nuclear Information System (INIS)

Leveille, J.P.

1976-01-01

An attempt is made to generalize a theorem of Jauch on the equivalence of local gauge symmetry and Galilean symmetry to relativistic theories. One first proves a converse to Jauch's theorem deriving the Galilei algebra from a locality postulate. When generalized to the relativistic case the locality postulate leads one to the relativistic dynamical group g 5 . A possible physical interpretation of g 5 as a relativistic dynamical group is given. An attempt to describe the dynamics solely in Minkowski space-time leads, in conjunction with the locality postulate, to a new relativistic dynamical algebra. We found that this new algebra is realized by field theoretical examples which exclude quantum electrodynamics, however, and other known gauge theories. This latter development forces one to seriously question the validity of the locality postulate. One concludes by proving a general theorem about the nonimplementability of local transformations by global operators independent of space-time in field theory

A laboratory evaluation of the influence of weighing gauges performance on extreme events statistics

Science.gov (United States)

Colli, Matteo; Lanza, Luca

2014-05-01

The effects of inaccurate ground based rainfall measurements on the information derived from rain records is yet not much documented in the literature. La Barbera et al. (2002) investigated the propagation of the systematic mechanic errors of tipping bucket type rain gauges (TBR) into the most common statistics of rainfall extremes, e.g. in the assessment of the return period T (or the related non-exceedance probability) of short-duration/high intensity events. Colli et al. (2012) and Lanza et al. (2012) extended the analysis to a 22-years long precipitation data set obtained from a virtual weighing type gauge (WG). The artificial WG time series was obtained basing on real precipitation data measured at the meteo-station of the University of Genova and modelling the weighing gauge output as a linear dynamic system. This approximation was previously validated with dedicated laboratory experiments and is based on the evidence that the accuracy of WG measurements under real world/time varying rainfall conditions is mainly affected by the dynamic response of the gauge (as revealed during the last WMO Field Intercomparison of Rainfall Intensity Gauges). The investigation is now completed by analyzing actual measurements performed by two common weighing gauges, the OTT Pluvio2 load-cell gauge and the GEONOR T-200 vibrating-wire gauge, since both these instruments demonstrated very good performance under previous constant flow rate calibration efforts. A laboratory dynamic rainfall generation system has been arranged and validated in order to simulate a number of precipitation events with variable reference intensities. Such artificial events were generated basing on real world rainfall intensity (RI) records obtained from the meteo-station of the University of Genova so that the statistical structure of the time series is preserved. The influence of the WG RI measurements accuracy on the associated extreme events statistics is analyzed by comparing the original intensity

D-instantons on orbifolds and gauge/gravity correspondence

International Nuclear Information System (INIS)

Tanzini, Alessandro

2002-01-01

D-instantons are used to probe the near-horizon geometry of D3-branes systems on orbifold spaces. For fractional D3-branes, D-instanton calculus correctly reproduces the gauge β-function and U(1) R anomaly of the corresponding N=2 non-conformal Super Yang-Mills theories. For D3-branes wrapping the orbifold singularity, D-instantons can be identified with gauge instantons on ALE space, providing evidence of AdS/CFT duality for gauge theories on curved spaces. (Abstract Copyright[2002], Wiley Periodicals, Inc.)

Stereotactic core biopsy: Comparison of 11 gauge with 8 gauge vacuum assisted breast biopsy

Energy Technology Data Exchange (ETDEWEB)

Venkataraman, Shambhavi, E-mail: svenkata@bidmc.harvard.edu [Department of Radiology, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA 02215 (United States); Dialani, Vandana [Department of Radiology, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA 02215 (United States); Gilmore, Hannah L. [Department of Pathology, UH Case Medical Center, 11100 Euclid Ave, Cleveland, OH 44106 (United States); Mehta, Tejas S. [Department of Radiology, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA 02215 (United States)

2012-10-15

Purpose: The compare the performance and ability to obtain a correct diagnosis on needle biopsy between 11 gauge and 8 gauge vacuum assisted biopsy devices. Materials and methods: Hospital records of all consecutive stereotactic core biopsies performed over five years were retrospectively reviewed in compliance Health Insurance Portability and Accountability Act (HIPPA) policy and with approval from the hospital institutional review board (IRB). Pathology from core biopsy was compared with surgical pathology and/or imaging follow-up. A histological underestimation was defined if the surgical excision yielded a higher grade on pathology which changed management. Results: 828 needle core biopsies (47.5%, 393/828 with 11 gauge and 52.5%, 435/828 with 8 gauge) yielded 471 benign, 153 high risk and 204 malignant lesions. 30/193 (15.5%) 11 gauge lesions and 16/185 (8.6%) 8 gauge lesions demonstrated higher grade pathology on surgical excision. The difference in the rates of the number of correct diagnoses on core needle biopsy between 11 gauge (363/393, 92.4%) and 8 gauge (419/435, 96.3%) based on either surgical or clinical/imaging follow up and the difference in the number of discordant benign core biopsies between 11 (17/217, 7.8%) and 8 gauge (4/254, 1.6%) necessitating a surgical biopsy was significant (P = 0.013; P = 0.001). Although there were more underestimations with the 11 gauge (25/193, 13.0%) than 8 gauge (15/185, 8.1%) needle, this was not significant. Conclusion: Our study demonstrates improved performance and increased diagnostic ability of 8 gauge needle over 11 gauge in obtaining a correct diagnosis on needle biopsy.

Extended pure Yang-Mills gauge theories with scalar and tensor gauge fields

International Nuclear Information System (INIS)

Gabrielli, E.

1991-01-01

The usual abelian gauge theory is extended to an interacting Yang-Mills-like theory containing vector, scalar and tensor gauge fields. These gauge fields are seen as components along the Clifford algebra basis of a gauge vector-spinorial field. Scalar fields φ naturally coupled to vector and tensor fields have been found, leading to a natural φ 4 coupling in the lagrangian. The full expression of the lagrangian for the euclidean version of the theory is given. (orig.)

Global Gauge Anomalies in Two-Dimensional Bosonic Sigma Models

Science.gov (United States)

Gawȩdzki, Krzysztof; Suszek, Rafał R.; Waldorf, Konrad

2011-03-01

We revisit the gauging of rigid symmetries in two-dimensional bosonic sigma models with a Wess-Zumino term in the action. Such a term is related to a background closed 3-form H on the target space. More exactly, the sigma-model Feynman amplitudes of classical fields are associated to a bundle gerbe with connection of curvature H over the target space. Under conditions that were unraveled more than twenty years ago, the classical amplitudes may be coupled to the topologically trivial gauge fields of the symmetry group in a way which assures infinitesimal gauge invariance. We show that the resulting gauged Wess-Zumino amplitudes may, nevertheless, exhibit global gauge anomalies that we fully classify. The general results are illustrated on the example of the WZW and the coset models of conformal field theory. The latter are shown to be inconsistent in the presence of global anomalies. We introduce a notion of equivariant gerbes that allow an anomaly-free coupling of the Wess-Zumino amplitudes to all gauge fields, including the ones in non-trivial principal bundles. Obstructions to the existence of equivariant gerbes and their classification are discussed. The choice of different equivariant structures on the same bundle gerbe gives rise to a new type of discrete-torsion ambiguities in the gauged amplitudes. An explicit construction of gerbes equivariant with respect to the adjoint symmetries over compact simply connected simple Lie groups is given.

Performance of modern tide gauges: towards mm-level accuracy

Directory of Open Access Journals (Sweden)

Belén Martín Míguez

2012-09-01

Full Text Available Considerable efforts are being made worldwide to upgrade tide gauge networks using new technologies. Because of the unique location of the Kerguelen Islands, the measurement of sea level there has received particular attention, with up to four systems equipped with modern sensors functioning simultaneously (two pressure tide gauges, a radar tide gauge, and a GPS-equipped buoy. We analysed and compared the sea level data obtained with these systems from 2003 to 2010, together with a time series of tide pole observations. This is the first time that a multi-comparison study with tide gauges has been undertaken over such a long time span and that the stability of modern radar tide gauges has been examined. The multi-comparison enabled us to evaluate the performance of the tide gauges in several frequency ranges, identify errors and estimate their magnitude. The drift of the pressure sensors (up to 8.0 mm/yr was found to be one of the most relevant sources of systematic error. Other sources of difference such as clock drift, scale error and different locations of the instruments were also detected. After correcting the time series of sea level for these errors we estimated an upper bound for the radar instrumental error in field condition at ~0.3 cm.

Gauging of 1D-space translations for nonrelativistic matter - Geometric bags

International Nuclear Information System (INIS)

Stichel, P.C.

2000-01-01

We develop in a systematic fashion the idea of gauging 1D-space translations with fixed Newtonian time for nonrelativistic matter (particles and fields). By starting with a nonrelativistic free theory we obtain its minimal gauge invariant extension by introducing two gauge fields with a Maxwellian self interaction. We fix the gauge so that the residual symmetry group is the Galilei group and construct a representation of the extended Galilei algebra. The reduced N-particle Lagrangian describes geodesic motion in a (N-1)-dimensional (Pseudo-) Riemannian space. The singularity of the metric for negative gauge coupling leads in classical dynamics to the formation of geometric bags in the case of two or three particles. The ordering problem within the quantization scheme for N-particles is solved by canonical quantization of a pseudoclassical Schroedinger theory obtained by adding to the continuum generalization of the point-particle Lagrangian an appropriate quantum correction. We solve the two-particle bound state problem for both signs of the gauge coupling. At the end we speculate on the possible physical relevance of the new interaction induced by the gauge fields

Second-order gauge-invariant perturbations during inflation

International Nuclear Information System (INIS)

Finelli, F.; Marozzi, G.; Vacca, G. P.; Venturi, G.

2006-01-01

The evolution of gauge invariant second-order scalar perturbations in a general single field inflationary scenario are presented. Different second-order gauge-invariant expressions for the curvature are considered. We evaluate perturbatively one of these second order curvature fluctuations and a second-order gauge-invariant scalar field fluctuation during the slow-roll stage of a massive chaotic inflationary scenario, taking into account the deviation from a pure de Sitter evolution and considering only the contribution of super-Hubble perturbations in mode-mode coupling. The spectra resulting from their contribution to the second order quantum correlation function are nearly scale-invariant, with additional logarithmic corrections with respect to the first order spectrum. For all scales of interest the amplitude of these spectra depends on the total number of e-folds. We find, on comparing first and second order perturbation results, an upper limit to the total number of e-folds beyond which the two orders are comparable

W∞ gauge theory and the quantum Hall effect

International Nuclear Information System (INIS)

Shizuya, K.

1994-05-01

It is shown that a planar system of Hall electrons coupled to an applied electromagnetic field is written in the form of a W ∞ gauge theory. The associated W ∞ gauge field is expressed nonlinearly in terms of an infinite set of multipoles of the electromagnetic field. The W ∞ transformations generate mixing among the Landau levels. They provide a systematic way to classify the electromagnetic characteristics of the Hall system according to the resolution of external probes. In particular, an exact long-wavelength connection is derived between the carrier density and the Hall conductance in the presence of electron-electron interactions. Our approach is complementary to an earlier one and reveals a dual role the W ∞ gauge symmetry plays in the Hall dynamics. (author)

Yang-Mills theories in axial and light-cone gauges, analytic regularization and Ward identities

International Nuclear Information System (INIS)

Lee, H.C.

1984-12-01

The application of the principles of generalization and analytic continuation to the regularization of divergent Feynman integrals is discussed. The technique, or analytic regularization, which is a generalization of dimensional regularization, is used to derive analytic representations for two classes of massless two-point integrals. The first class is based on the principal-value prescription and includes integrals encountered in quantum field theories in the ghost-free axial gauge (n.A=0), reducing in a special case to integrals in the light-cone gauge (n.A=0,n 2 =0). The second class is based on the Mandelstam prescription devised espcially for the light-cone gauge. For some light-cone gauge integrals the two representations are not equivalent. Both classes include as a subclass integrals in the Lorentz covariant 'zeta-gauges'. The representations are used to compute one-loop corrections to the self-energy and the three-vertex in Yang-Mills theories in the axial and light-cone gauges, showing that the two- and three-point Ward identities are satisfied; to illustrate that ultraviolet and infrared singularities, indistinguishable in dimensional regularization, can be separated analytically; and to show that certain tadpole integrals vanish because of an exact cancellation between ultraviolet and infrared singularities. In the axial gauge, the wavefunction and vertex renormalization constants, Z 3 and Z 1 , are identical, so that the β-function can be directly derived from Z 3 the result being the same as that computed in the covariant zeta-gauges. Preliminary results suggest that the light-cone gauge in the Mandelstam prescription, but not in the principal value prescription, has the same renormalization property of the axial gauge

Gauge invariance and Nielsen identities

International Nuclear Information System (INIS)

Lima, A.F. de; Bazaia, D.

1989-01-01

The one-loop contribution to the effective potential and mass are computed within the context of scalar electrodynamics for the class of general R gauges in the MS scheme. These calculations are performed in order to construct a non-trivial verification of the corresponding Nielsen identities within the context of the Higgs model. Some brief comments on the Coleman-Weinberg model are also included. (author) [pt

Nucleonic gauges in Poland and new approach to their calibration

International Nuclear Information System (INIS)

Urbanski, P.

2000-01-01

The current status of manufacturing and application of radioisotope gauges in Poland is presented. Metrological performance of the gauges is briefly described and their expected future prospects on the market of the industrial measuring instruments are discussed. Progress in electronic engineering and common use of the microprocessor systems in the radioisotope gauges made possible application of the sophisticated methods of signal processing and data treatment, as for example statistical multivariate analysis. Some examples of the multivariate calibration of nucleonic gauges are presented. Application of the partial least square regression (PLS) and artificial neural network (ANN) for calibration of the gauges has been shown. (author)

Cluster-enriched Yang-Baxter equation from SUSY gauge theories

Science.gov (United States)

Yamazaki, Masahito

2018-04-01

We propose a new generalization of the Yang-Baxter equation, where the R-matrix depends on cluster y-variables in addition to the spectral parameters. We point out that we can construct solutions to this new equation from the recently found correspondence between Yang-Baxter equations and supersymmetric gauge theories. The S^2 partition function of a certain 2d N=(2,2) quiver gauge theory gives an R-matrix, whereas its FI parameters can be identified with the cluster y-variables.

Chiral gauged Wess-Zumino-Witten theories and coset models in conformal field theory

International Nuclear Information System (INIS)

Chung, S.; Tye, S.H.

1993-01-01

The Wess-Zumino-Witten (WZW) theory has a global symmetry denoted by G L direct-product G R . In the standard gauged WZW theory, vector gauge fields (i.e., with vector gauge couplings) are in the adjoint representation of the subgroup H contained-in G. In this paper, we show that, in the conformal limit in two dimensions, there is a gauged WZW theory where the gauge fields are chiral and belong to the subgroups H L and H R where H L and H R can be different groups. In the special case where H L =H R , the theory is equivalent to vector gauged WZW theory. For general groups H L and H R , an examination of the correlation functions (or more precisely, conformal blocks) shows that the chiral gauged WZW theory is equivalent to (G/H L ) L direct-product(G/H R ) R coset models in conformal field theory

Chemical potentials in gauge theories

International Nuclear Information System (INIS)

Actor, A.; Pennsylvania State Univ., Fogelsville

1985-01-01

One-loop calculations of the thermodynamic potential Ω are presented for temperature gauge and non-gauge theories. Prototypical formulae are derived which give Ω as a function of both (i) boson and/or fermion chemical potential, and in the case of gauge theories (ii) the thermal vacuum parameter Asub(O)=const (Asub(μ) is the euclidean gauge potential). From these basic abelian gauge theory formulae, the one-loop contribution to Ω can readily be constructed for Yang-Mills theories, and also for non-gauge theories. (orig.)

Doses from portable gauges

International Nuclear Information System (INIS)

Linauskas, S.H.

1988-08-01

Field studies to measure actual radiation exposures of operators of commercial moisture-density gauges were undertaken in several regions of Canada. Newly developed bubble detector dosimeter technology and conventional dosimetry such as thermoluminescent dosimeters (TLDs), integrating electronic dosimeters (DRDs), and CR-39 neutron track-etch detectors were used to estimate the doses received by 23 moisture-density gauge operators and maintenance staff. These radiation dose estimates were supported by mapping radiation fields and accounting for the time an operator was near a gauge. Major findings indicate that gauge maintenance and servicing workers were more likely than gauge operators to receive exposures above the level of 5 mSv, and that neutron doses were roughly the same as gamma doses. Gauge operators receive approximately 75% of their dose when transporting and carrying the gauge. Dose to their hands is similar to the dose to their trunks, but the dose to their feet area is 6 to 30 times higher. Gamma radiation is the primary source of radiation contributing to operator dose

Chiral symmetry breaking in gauge theories from Reggeon diagram analysis

International Nuclear Information System (INIS)

White, A.R.

1991-01-01

It is argued that reggeon diagrams can be used to study dynamical properties of gauge theories containing a large number of massless fermions. SU(2) gauge theory is studied in detail and it is argued that there is a high energy solution which is analogous to the solution of the massless Schwinger model. A generalized winding-number condensate produces the massless pseudoscalar spectrum associated with chiral symmetry breaking and a ''trivial'' S-Matrix

BMN gauge theory as a quantum mechanical system

DEFF Research Database (Denmark)

Beisert, N.; Kristjansen, C.; Plefka, J.

2003-01-01

We rigorously derive an effective quantum mechanical Hamiltonian from N = 4 gauge theory in the BMN limit. Its eigenvalues yield the exact one-loop anomalous dimensions of scalar two-impurity BMN operators for all genera. It is demonstrated that this reformulation vastly simplifies computations. ...

The gauge-invariant canonical energy-momentum tensor

Science.gov (United States)

Lorcé, Cédric

2016-03-01

The canonical energy-momentum tensor is often considered as a purely academic object because of its gauge dependence. However, it has recently been realized that canonical quantities can in fact be defined in a gauge-invariant way provided that strict locality is abandoned, the non-local aspect being dictacted in high-energy physics by the factorization theorems. Using the general techniques for the parametrization of non-local parton correlators, we provide for the first time a complete parametrization of the energy-momentum tensor (generalizing the purely local parametrizations of Ji and Bakker-Leader-Trueman used for the kinetic energy-momentum tensor) and identify explicitly the parts accessible from measurable two-parton distribution functions (TMDs and GPDs). As by-products, we confirm the absence of model-independent relations between TMDs and parton orbital angular momentum, recover in a much simpler way the Burkardt sum rule and derive three similar new sum rules expressing the conservation of transverse momentum.

The gauge-invariant canonical energy-momentum tensor

International Nuclear Information System (INIS)

Lorce, C.

2016-01-01

The canonical energy-momentum tensor is often considered as a purely academic object because of its gauge dependence. However, it has recently been realized that canonical quantities can in fact be defined in a gauge-invariant way provided that strict locality is abandoned, the non-local aspect being dictated in high-energy physics by the factorization theorems. Using the general techniques for the parametrization of non-local parton correlators, we provide for the first time a complete parametrization of the energy-momentum tensor (generalizing the purely local parametrizations of Ji and Bakker-Leader-Trueman used for the kinetic energy-momentum tensor) and identify explicitly the parts accessible from measurable two-parton distribution functions (TMD and GPD). As by-products, we confirm the absence of model-independent relations between TMDs and parton orbital angular momentum, recover in a much simpler way the Burkardt sum rule and derive 3 similar new sum rules expressing the conservation of transverse momentum. (author)

Search for new heavy charged gauge bosons

Energy Technology Data Exchange (ETDEWEB)

Magass, Carsten Martin

2007-11-02

The TEVATRON proton-antiproton collider at FERMILAB (near Chicago/USA) is operating at a center-of-mass energy of {radical}(s)=1.96 TeV since March 2001. This analysis uses data taken with the DOe detector until February 2006 corresponding to an integrated luminosity of about {integral}Ldt=1 fb{sup -1}. Using this dataset, a search for a new heavy charged gauge boson W{sup '} and its subsequent decay into an electron and a neutrino is performed: p anti p{yields}W{sup '}+X{yields}e{nu}+X. Additional gauge bosons (including the equivalent to the Z, the Z{sup '}) are introduced in many extensions to the Standard Model of particle physics. Assuming the most general case, the new gauge group can comprise a new mixing angle and new couplings. Here, the Altarelli Reference Model is considered which represents a generalization of the Manifest Left-Right Symmetric Model with light right-handed neutrinos. This model makes the assumptions that the new gauge boson W{sup '} has the same couplings as the Standard Model W boson and that there is no mixing. Hence, the W{sup '} is a heavy copy of the Standard Model W boson. The clear decay signature (in analogy to the decay of the W) contains an isolated electron with extreme high energy which is important for triggering. The neutrino can not be detected, but it gives rise to missing energy in the detector. The Jacobian peak in the transverse mass distribution stemming from the W decay is used for calibration, whereas the tail of the transverse mass distribution is searched for a possible W{sup '} signal. The data agrees with the expectation from background processes. For instance, in the data 37 events are reconstructed with transverse masses above 300 GeV compared to a prediction of 37.1{+-}2.1(stat){sup +6.0}{sub -3.7}(sys) background events. Since no significant excess is found in the data, an upper limit is set on the production cross section for heavy charged gauge bosons decaying into electron and neutrino, {sigma}{sub W

Search for new heavy charged gauge bosons

Energy Technology Data Exchange (ETDEWEB)

Magass, Carsten Martin

2007-11-02

The TEVATRON proton-antiproton collider at FERMILAB (near Chicago/USA) is operating at a center-of-mass energy of {radical}(s)=1.96 TeV since March 2001. This analysis uses data taken with the DOe detector until February 2006 corresponding to an integrated luminosity of about {integral}Ldt=1 fb{sup -1}. Using this dataset, a search for a new heavy charged gauge boson W{sup '} and its subsequent decay into an electron and a neutrino is performed: p anti p{yields}W{sup '}+X{yields}e{nu}+X. Additional gauge bosons (including the equivalent to the Z, the Z{sup '}) are introduced in many extensions to the Standard Model of particle physics. Assuming the most general case, the new gauge group can comprise a new mixing angle and new couplings. Here, the Altarelli Reference Model is considered which represents a generalization of the Manifest Left-Right Symmetric Model with light right-handed neutrinos. This model makes the assumptions that the new gauge boson W{sup '} has the same couplings as the Standard Model W boson and that there is no mixing. Hence, the W{sup '} is a heavy copy of the Standard Model W boson. The clear decay signature (in analogy to the decay of the W) contains an isolated electron with extreme high energy which is important for triggering. The neutrino can not be detected, but it gives rise to missing energy in the detector. The Jacobian peak in the transverse mass distribution stemming from the W decay is used for calibration, whereas the tail of the transverse mass distribution is searched for a possible W{sup '} signal. The data agrees with the expectation from background processes. For instance, in the data 37 events are reconstructed with transverse masses above 300 GeV compared to a prediction of 37.1{+-}2.1(stat){sup +6.0}{sub -3.7}(sys) background events. Since no significant excess is found in the data, an upper limit is set on the production cross section for heavy charged gauge bosons decaying into electron

High accuracy step gauge interferometer

Science.gov (United States)

Byman, V.; Jaakkola, T.; Palosuo, I.; Lassila, A.

2018-05-01

Step gauges are convenient transfer standards for the calibration of coordinate measuring machines. A novel interferometer for step gauge calibrations implemented at VTT MIKES is described. The four-pass interferometer follows Abbe’s principle and measures the position of the inductive probe attached to a measuring head. The measuring head of the instrument is connected to a balanced boom above the carriage by a piezo translation stage. A key part of the measuring head is an invar structure on which the inductive probe and the corner cubes of the measuring arm of the interferometer are attached. The invar structure can be elevated so that the probe is raised without breaking the laser beam. During probing, the bending of the probe and the interferometer readings are recorded and the measurement face position is extrapolated to zero force. The measurement process is fully automated and the face positions of the steps can be measured up to a length of 2 m. Ambient conditions are measured continuously and the refractive index of air is compensated for. Before measurements the step gauge is aligned with an integrated 2D coordinate measuring system. The expanded uncertainty of step gauge calibration is U=\\sqrt{{{(64 nm)}2}+{{(88× {{10}-9}L)}2}} .

SU(2) gauge theory in the maximally Abelian gauge without monopoles

International Nuclear Information System (INIS)

Shmakov, S.Yu.; Zadorozhnyj, A.M.

1995-01-01

We present an algorithm for simulation of SU(2) lattice gauge theory under the maximally Abelian (MA) gauge and first numerical results for the theory without Abelian monopoles. The results support the idea that nonperturbative interaction arises between monopoles and residual Abelian field and the other interactions are perturbative. It is shown that the Gribov region for the theory with the MA gauge fixed is non-connected. 12 refs., 1 tab

Concerning Gribov vacuum copies in non-abelian gauge theory

International Nuclear Information System (INIS)

Frampton, P.H.; Palmer, W.F.; Pinsky, S.S.

1978-01-01

Construction of gauge field configurations A/sub μ//sup a/(x) in an SU(2) Yang-Mills theory satisfying everywhere F/sub μν//sup a/(x) = 0 is discussed. Using the method of sections, a field related to the zero-size limit of an instanton is presented. The corresponding limit for a multi-instanton solution requires a generalization of the Landau gauge condition. Finally, an alternative method and explicit solution is given for the case of delta/sub μ/A/sub μ//sup a/ = 0

Non-Abelian gauge theory of fields associated with dyons

International Nuclear Information System (INIS)

Rajput, B.S.; Kumar, S.R.

1983-01-01

A suitable Lorentz invariant non-Abelian gauge theory of the fields associated with dyons has been constructed to describe the dual dynamics between colour isocharges and topological charges. It has been shown that the generalized particle current is gauge covariant and not conserved in non-Abelian theory. It has also been shown that in this theory the unphysical string variables and unphysical charged fields are not needed and that any extra constraint to maintain the dual symmetry of field equation and Lagrangian is also not needed. (author)

Canonical ward identities in generalized QCD

International Nuclear Information System (INIS)

Li Ziping

1995-01-01

The canonical Ward identities for a system with singular higher-order Lagrangian are derived and some application to the generalized QCD are given. The new relations of the Ward identities for gauge ghost field proper vertices are obtained which differ from the usual Ward-Takahashi identities arising from BRS invariance. The expressions for PCAC and generalized PCAC of AVV vertices are also obtained

Algebraic isomorphism in two-dimensional anomalous gauge theories

International Nuclear Information System (INIS)

Carvalhaes, C.G.; Belvedere, L.V.; Filho, H.B.; Natividade, C.P.

1997-01-01

The operator solution of the anomalous chiral Schwinger model is discussed on the basis of the general principles of Wightman field theory. Some basic structural properties of the model are analyzed taking a careful control on the Hilbert space associated with the Wightman functions. The isomorphism between gauge noninvariant and gauge invariant descriptions of the anomalous theory is established in terms of the corresponding field algebras. We show that (i) the Θ-vacuum representation and (ii) the suggested equivalence of vector Schwinger model and chiral Schwinger model cannot be established in terms of the intrinsic field algebra. copyright 1997 Academic Press, Inc

Covariant field equations, gauge fields and conservation laws from Yang-Mills matrix models

International Nuclear Information System (INIS)

Steinacker, Harold

2009-01-01

The effective geometry and the gravitational coupling of nonabelian gauge and scalar fields on generic NC branes in Yang-Mills matrix models is determined. Covariant field equations are derived from the basic matrix equations of motions, known as Yang-Mills algebra. Remarkably, the equations of motion for the Poisson structure and for the nonabelian gauge fields follow from a matrix Noether theorem, and are therefore protected from quantum corrections. This provides a transparent derivation and generalization of the effective action governing the SU(n) gauge fields obtained in [1], including the would-be topological term. In particular, the IKKT matrix model is capable of describing 4-dimensional NC space-times with a general effective metric. Metric deformations of flat Moyal-Weyl space are briefly discussed.

Gauge-invariant on-shell Z1 in QED and QCD

International Nuclear Information System (INIS)

Fleischer, J.; Tarasov, O.V.

1992-01-01

Results of the two-loop calculation of the renormalization constant Z 1 for the on-shell fermion-fermion-vector vertex function of a general gauge theory with one massive fermion and the other particles massless are presented. Computations were performed in n dimensions and for an arbitrary covariant gauge. We found Z 1 to be gauge invariant in a renormalization scheme with simultaneous dimensional regularization of ultraviolet and infrared divergences. The charge renormalization constant in this scheme has ultraviolet and infrared divergences. It is found that infrared divergent terms in one- and two-loop approximation are proportional to be appropriate coefficient of the β function determined by ultraviolet divergences of massless particles, i.e. gluons and massless fermions. (orig.)

Gauge see-saw: A mechanism for a light gauge boson

Energy Technology Data Exchange (ETDEWEB)

Lee, Hye-Sung, E-mail: hlee@ibs.re.kr; Seo, Min-Seok, E-mail: minseokseo@ibs.re.kr

2017-04-10

There has been rapidly growing interest in the past decade in a new gauge boson which is considerably lighter than the standard model Z boson. A well-known example of this kind is the so-called dark photon, and it is actively searched for in various experiments nowadays. It would be puzzling to have a new gauge boson which is neither massless nor electroweak scale, but possesses a rather small yet nonzero mass. We present a mechanism that can provide a light gauge boson as a result of a mass matrix diagonalization.

The application of *-products to noncommutative geometry and gauge theory

International Nuclear Information System (INIS)

Sykora, A.

2004-06-01

Due to the singularities arising in quantum field theory and the difficulties in quantizing gravity it is often believed that the description of spacetime by a smooth manifold should be given up at small length scales or high energies. In this work we will replace spacetime by noncommutative structures arising within the framework of deformation quantization. The ordinary product between functions will be replaced by a *-product, an associative product for the space of functions on a manifold. We develop a formalism to realize algebras defined by relations on function spaces. For this purpose we construct the Weyl-ordered *-product and present a method how to calculate *-products with the help of commuting vector fields. Concepts developed in noncommutative differential geometry will be applied to this type of algebras and we construct actions for noncommutative field theories. In the classical limit these noncommutative theories become field theories on manifolds with nonvanishing curvature. It becomes clear that the application of *-products is very fruitful to the solution of noncommutative problems. In the semiclassical limit every *-product is related to a Poisson structure, every derivation of the algebra to a vector field on the manifold. Since in this limit many problems are reduced to a couple of differential equations the *-product representation makes it possible to construct noncommutative spaces corresponding to interesting Riemannian manifolds. Derivations of *-products makes it further possible to extend noncommutative gauge theory in the Seiberg-Witten formalism with covariant derivatives. The resulting noncommutative gauge fields may be interpreted as one forms of a generalization of the exterior algebra of a manifold. For the Formality *-product we prove the existence of the abelian Seiberg-Witten map for derivations of these *-products. We calculate the enveloping algebra valued non abelian Seiberg-Witten map pertubatively up to second order for

On low rank classical groups in string theory, gauge theory and matrix models

International Nuclear Information System (INIS)

Intriligator, Ken; Kraus, Per; Ryzhov, Anton V.; Shigemori, Masaki; Vafa, Cumrun

2004-01-01

We consider N=1 supersymmetric U(N), SO(N), and Sp(N) gauge theories, with two-index tensor matter and added tree-level superpotential, for general breaking patterns of the gauge group. By considering the string theory realization and geometric transitions, we clarify when glueball superfields should be included and extremized, or rather set to zero; this issue arises for unbroken group factors of low rank. The string theory results, which are equivalent to those of the matrix model, refer to a particular UV completion of the gauge theory, which could differ from conventional gauge theory results by residual instanton effects. Often, however, these effects exhibit miraculous cancellations, and the string theory or matrix model results end up agreeing with standard gauge theory. In particular, these string theory considerations explain and remove some apparent discrepancies between gauge theories and matrix models in the literature

Nonlinear symmetries of black hole entropy in gauged supergravity

Energy Technology Data Exchange (ETDEWEB)

Klemm, Dietmar [Dipartimento di Fisica, Università di Milano,and INFN, Sezione di Milano,Via Celoria 16, I-20133 Milano (Italy); Marrani, Alessio [Museo Storico della Fisica e Centro Studi e Ricerche ‘Enrico Fermi’,Via Panisperna 89A, I-00184 Roma (Italy); Dipartimento di Fisica e Astronomia ‘Galileo Galilei’, Università di Padova,and INFN, Sezione di Padova,Via Marzolo 8, I-35131 Padova (Italy); Petri, Nicolò; Rabbiosi, Marco [Dipartimento di Fisica, Università di Milano,and INFN, Sezione di Milano,Via Celoria 16, I-20133 Milano (Italy)

2017-04-04

Freudenthal duality in N=2, D=4 ungauged supergravity is generated by an anti-involutive operator that acts on the electromagnetic fluxes, and results to be a symmetry of the Bekenstein-Hawking entropy. We show that, with a suitable extension, this duality can be generalized to the abelian gauged case as well, even in presence of hypermultiplets. By defining Freudenthal duality along the scalar flow, one can prove that two configurations of charges and gaugings linked by the Freudenthal operator share the same set of values of the scalar fields at the black hole horizon. Consequently, Freudenthal duality is promoted to a nonlinear symmetry of the black hole entropy. We explicitly show this invariance for the model with prepotential F=−iX{sup 0}X{sup 1} and Fayet-Iliopoulos gauging.

Dynamical supersymmetry breaking and gauge anomalies

International Nuclear Information System (INIS)

Zhang, H.

1991-01-01

Some aspects of supersymmetric gauge theories are discussed. It is shown that dynamical supersymmetry breaking does not occur in supersymmetric QED in higher dimensions. The cancellation of both local (perturbative) and global (non-perturbative) gauge anomalies are also discussed in supersymmetric gauge theories. We argue that there is no dynamical supersymmetry breaking in higher dimensions in any supersymmetric gauge theories free of gauge anomalies. It is also shown that for supersymmetric gauge theories in higher dimensions with a compact connected simple gauge group, when the local anomaly-free condition is satisfied, there can be at most a possible Z 2 global gauge anomaly in extended supersymmetric SO(10) (or spin (10)) gauge theories in D=10 dimensions containing additional Weyl fermions in a spinor representation of SO(10) (or spin (10)). In four dimensions with local anomaly-free condition satisfied, the only possible global gauge anomalies in supersymmetric gauge theories are Z 2 global gauge anomalies for extended supersymmetric SP(2N) (N=rank) gauge theories containing additional Weyl fermions in a representation of SP(2N) with an odd 2nd-order Dynkin index. (orig.)

On the entanglement entropy for gauge theories

International Nuclear Information System (INIS)

Ghosh, Sudip; Soni, Ronak M; Trivedi, Sandip P.

2015-01-01

We propose a definition for the entanglement entropy of a gauge theory on a spatial lattice. Our definition applies to any subset of links in the lattice, and is valid for both Abelian and Non-Abelian gauge theories. For ℤ_N and U(1) theories, without matter, our definition agrees with a particular case of the definition given by Casini, Huerta and Rosabal. We also argue that in general, both for Abelian and Non-Abelian theories, our definition agrees with the entanglement entropy calculated using a definition of the replica trick. Our definition, however, does not agree with some standard ways to measure entanglement, like the number of Bell pairs which can be produced by entanglement distillation.

Spontaneous symmetry breaking in local gauge quantum field theory; the Higgs mechanism

International Nuclear Information System (INIS)

Strocchi, F.

1977-01-01

Spontaneous symmetry breakings in indefinite metric quantum field theories are analyzed and a generalization of the Goldstone theorem is proved. The case of local gauge quantum field theories is discussed in detail and a characterization is given of the occurrence of the Higgs mechanism versus the Goldstone mechanism. The Higgs phenomenon is explained on general grounds without the introduction of the so-called Higgs fields. The basic property is the relation between the local internal symmetry group and the local group of gauge transformations of the second kind. Spontaneous symmetry breaking of c-number gauge transformations of the second kind is shown to always occur if there are charged local fields. The implications about the absence of mass gap in the Wightman functions and the occurrence of massless particles associated with the unbroken generators in the Higgs phenomenon are discussed. (orig.) [de

Transformation properties of the effective action for gauge theories

International Nuclear Information System (INIS)

Otten, C.M.E.

1978-01-01

The main purpose of this thesis is to investigate the gauge invariance properties of the effective action. In fact, the Slavnov-Taylor identities for the effective action are nothing but a compact formulation of the gauge symmetry properties of the theory. Chapter II of this thesis focuses on the derivation of the Slavnov-Taylor identities for a general gauge theory, especially the identities for proper vertices. An analysis of the group- and invariance structure of the effective action is given, using both diagrammatic and functional techniques. Moreover, the Slavnov-Taylor identities are written out explicitely up to the order g 4 , where g is the coupling constant of the theory. The general theory outlined in chapter II is applied to an SU(2) model containing vector bosons, scalar particles and leptons. Specifically, the interplay between finite one-loop effects and the invariance structure of the model is studied in a certain limit (the so-called large Higgs mass limit). It is shown that the results can be fully interpreted on the basis of the Slavnov-Taylor identities for proper vertices. This is done in chapter III. (Auth.)

Restoration of the local gauge symmetry and color confinement in non-Abelian gauge theories

International Nuclear Information System (INIS)

Hata, Hiroyuki

1982-01-01

Restoration of the local gauge symmetry and its connection to color confinement is investigated in non-Abelian gauge theories with covariant gauge fixing. We consider the Noether current J sub(μ,#betta#)sup(a) of the local gauge transformation with transformation functions #betta#sup(b)(x) linear in x sub(μ); #betta#sup(b)(x) = delta sup(ab)x sub(#betta#). This current is conserved only in the physical subspace of the state vector space and in perturbation theory contains a massless pole communicating to the gauge field. We define the local gauge symmetry restoration as the disappearance of this massless ''Goldstone'' pole from J sub(μ,#betta#)sup(a). The restoration condition is obtained and it coincides exactly with the color confinement criterion proposed earlier by Kugo and Ojima. Quarks and other colored particles are shown to be confined in the local gauge symmetry restored phase by using the Ward identities of J sub(μ,#betta#)sup(a). (author)

Extended gauge sectors at future colliders: Report of the New Gauge Boson Subgroup

International Nuclear Information System (INIS)

Rizzo, T.G.

1996-12-01

The author summarizes the results of the New Gauge Boson Subgroup on the physics of extended gauge sectors at future colliders as presented at the 1996 Snowmass workshop. He discusses the direct and indirect search reaches for new gauge bosons at both hadron and lepton colliders as well as the ability of such machines to extract detailed information on the couplings of these particles to the fermions and gauge bosons of the Standard Model. 41 refs., 18 figs., 5 tabs

The gauge in general relativity

International Nuclear Information System (INIS)

Cohn, J.

1975-01-01

The view is taken that the field equations of General Relativity, without a definition of congruence of length and time intervals at different events, are without physical content. The possibility is explored that the customary Einstein field equations are to be used but with a different congruence definition than is customary. When these resulting equations are, in turn, expressed with the customary congruence, they comprise a new set of field equations physically not equivalent to either Einstein's or Brans-Dicke's formulations of general relativity. Similarities with Einstein's and Brans-Dicke's formulations are discussed, and the possibility of experimental confirmation of these new equations is also briefly considered. (author)

Feynman graphs and gauge theories for experimental physicists. 2. rev. ed.

International Nuclear Information System (INIS)

Schmueser, P.

1995-01-01

This book is an introduction to the foundations of quantum field theory with special regards to gauge theory. After a general introduction to relativistic wave equations the concept of Feynman graphs is introduced. Then after an introduction to the phenomenology of weak interactions and the principle of gauge invariance the standard model of the electroweak interaction is presented. Finally quantum chromodynamics is described. Every chapter contains exercise problems. (HSI)

Non-Abelian duality in N = 4 supersymmetric gauge theories

International Nuclear Information System (INIS)

Dorey, Nicholas; Fraser, Christophe; Hollowood, Timithy J.; Kneipp, Marco A.C.

1996-03-01

A semi-classical check of the Goddard-Nuyts-Olive (GNO) generalized duality conjecture for gauge theories with adjoint Higgs fields is performed for the case where the unbroken gauge group is non-Abelian. The monopole solutions of the theory transform under the non-Abelian part of the unbroken global symmetry and the associated component of the moduli space is a Lie group coset space. The well-known problems in introducing collective coordinates for these degrees-of-freedom are solved by considering suitable multi monopole configurations in which the long-range non-Abelian fields cancel. In the context of an N = 4 supersymmetric gauge theory, the multiplicity of BPS saturated states is given by the number of ground-states of a supersymmetric quantum mechanics on the compact internal moduli space. The resulting degeneracy is expressed as the Euler character of the coset space. In all cases the number of states is consistent with the dimensions of the multiplets of the unbroken dual gauge group, and hence the results provide strong support for the GNO conjecture. (author). 39 refs

Parastatistics and gauge symmetries

International Nuclear Information System (INIS)

Govorkov, A.B.

1982-01-01

A possible formulation of gauge symmetries in the Green parafield theory is analysed and the SO(3) gauge symmetry is shown to be on a distinct status. The Greenberg paraquark hypothesis turns out to be not equivalent to the hypothesis of quark colour SU(3)sub(c) symmetry. Specific features of the gauge SO(3) symmetry are discussed, and a possible scheme where it is an exact subgroup of the broken SU(3)sub(c) symmetry is proposed. The direct formulation of the gauge principle for the parafield represented by quaternions is also discussed

High energy behaviour of nonabelian gauge theories

International Nuclear Information System (INIS)

Bartels, J.

1979-10-01

The high energy behavior (in the Regge limit) of nonabelian gauge theories is reviewed. After a general remark concerning the question to what extent the Regge limit can be approached within perturbation theory, we first review the reggeization of elementary particles within nonabelian gauge theories. Then the derivation of a unitary high energy description of a massive (= spontaneously broken) nonabelian gauge model is described, which results in a complete reggeon calculus. There is strong evidence that the zero mass limit of this reggeon calculus exists, thus giving rise to the hope that the Regge behavior in pure Yang-Mills theories (QCD) can be reached in this way. In the final part of these lectures two possible strategies for solving this reggeon calculus (both for the massive and the massless case) are outlined. One of them leads to a geometrical picture in which the distribution of the wee partons obeys a diffusion law. The other one makes contact with reggeon field theory and predicts that QCD in the high energy limit is described by critical reggeon field theory. (orig.)

Chiral rings and anomalies in supersymmetric gauge theory

International Nuclear Information System (INIS)

Cachazo, Freddy; Witten, Edward; Seiberg, Nathan; Douglas, Michael R.

2002-01-01

Motivated by recent work of Dijkgraaf and Vafa, we study anomalies and the chiral ring structure in a supersymmetric U(N) gauge theory with an adjoint chiral superfield and an arbitrary superpotential. A certain generalization of the Konishi anomaly leads to an equation which is identical to the loop equation of a bosonic matrix model. This allows us to solve for the expectation values of the chiral operators as functions of a finite number of 'integration constants'. From this, we can derive the Dijkgraaf-Vafa relation of the effective superpotential to a matrix model. Some of our results are applicable to more general theories. For example, we determine the classical relations and quantum deformations of the chiral ring of N=1 super Yang-Mills theory with SU(N) gauge group, showing, as one consequence, that all supersymmetric vacua of this theory have a nonzero chiral condensate. (author)