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We analyze patterns of dynamical symmetry breaking in strongly coupled chiral gauge theories with direct-product gauge groups $G$. If the gauge coupling for a factor group $G_i \subset G$ becomes sufficiently strong, it can produce bilinear fermion condensates that break the $G_i$ symmetry itself and/or break other gauge symmetries $G_j \subset G$. Our comparative study of a number of strongly coupled direct-product chiral gauge theories elucidates how the patterns of symmetry breaking depend on the structure of $G$ and on the relative sizes of the gauge couplings corresponding to factor groups in the direct product., Comment: 25 pages, latex

We present an alternative approach to the problem of classification of first order Hamiltonian operators of differential-geometric type in 2D.

A general formalism to construct and improve supercurrents and source or anomaly superfields in two-derivative N=1 supersymmetric theories is presented. It includes arbitrary gauge and chiral superfields and a linear superfield coupled to gauge fields. These families of supercurrent structures are characterized by their energy-momentum tensors and R currents and they display a specific relation to the dilatation current of the theory. The linear superfield is introduced in order to describe the gauge coupling as a background (or propagating) field. Supersymmetry does not constrain the dependence on this gauge coupling field of gauge kinetic terms and holomorphicity restrictions are absent. Applying these results to an effective (Wilson) description of super-Yang-Mills theory, matching or cancellation of anomalies leads to an algebraic derivation of the all-order NSVZ beta function., Comment: 26 pages; contribution to Planck 2015, Ioannina, Greece, May 2015. Changes in footnotes, references added or updated

We study the mean-field BCS-BEC evolution of a uniform Fermi gas on a single-band triangular lattice, and construct its ground-state phase diagrams, showing a wealth of topological quantum phase transitions between gapped and gapless superfluids that are induced by the interplay of an out-of-plane Zeeman field and a generic non-Abelian gauge field., Comment: 7 pages with 4 figures

We explore field theories of a single p-form with equations of motions of order strictly equal to two and gauge invariance. We give a general method for the classification of such theories which are extensions to the p-forms of the Galileon models for scalars. Our classification scheme allows to compute an upper bound on the number of different such theories depending on p and on the space-time dimension. We are also able to build a non trivial Galileon like theory for a 3-form with gauge invariance and an action which is polynomial into the derivatives of the form. This theory has gauge invariant field equations but an action which is not, like a Chern-Simons theory. Hence the recently discovered no-go theorem stating that there are no non trivial gauge invariant vector Galileons (which we are also able here to confirm with our method) does not extend to other odd p cases., Comment: 29 pages

Totally symmetric continuous spin field propagating in (A)dS is studied. Lagrangian gauge invariant formulation for such field is developed. Lagrangian of continuous spin field is constructed in terms of double traceless tensor fields, while gauge transformations are constructed in terms of traceless gauge transformation parameters. de Donder like gauge condition that leads to simple gauge fixed Lagrangian is found. Gauge-fixed Lagrangian invariant under global BRST transformations is presented. The BRST Lagrangian is used for computation of a partition function. It is demonstrated that the partition function of the continuous spin field is equal to one. Various decoupling limits of the continuous spin field are also studied., Comment: Comments: 14 pages, v2: Formulas (3.24) (3.25), footnotes 1,3,4,5 and references added. Typos in eqs.(4.34) corrected

Статья посвящена методической проблеме придания наглядности одному из абстрактных видов симметрии симметрии относительно локального калибровочного преобразования. Рассматривается бесконечная однородная струна, расположенная в трехмерном пространстве. Пусть сначала струна совершает свободные колебания, описываемые функцией u(x, t) = cos kx exp [−ikct − iF(x, t)]. С точки зрения внешних наблюдателей, каждая точка струны вращается в плоскости Y Z. Добавочная фаза F обусловлена изменением направлений осей Y и Z в пространстве и во времени. На основе стоячей волны u(x, t) с помощью непрерывно выполняемых активных преобразований Пуанкаре (не затрагивающих, однако, функцию F) получена функция U(x, t) = Ψ(x, t) cos Φ(x, t), где Ψ = exp (iS(x, t)), описывающая вынужденные колебания специального вида. Фазу Φ(x, t) = 0 называем "частицей". Показано, что S является действием этой частицы. На основе S определяются полная энергия частицы и ее обобщенный импульс, в состав которых входят потенциальные функции V (x, t), A(x, t). Функция Ψ обращает в тождество уравнение Шредингера с нелокальным гамильтонианом, содержащим функции V , A. Тождество остается в силе при замене F на F − f(x, t), которая эквивалентна локальному калибровочному преобразованию в виде одновременной замены Ψ на exp (if(x, t))Ψ, V на V − ∂tf(x, t) и A на A + ∂xf(x, t). Таким образом, рассматриваемая модель обладает локальной калибровочной симметрией.DOI 10.14258/izvasu(2016)1-04, Our methodological aim is to make easy-tointerpret one of the abstract symmetries symmetry with respect to local gauge transformations. An infinite homogeneous string in three-dimensional space is considered. We first assume that free oscillations of the string are described by the function u(x, t) = cos kx exp [−ikct − iF(x, t)]. From the external observers viewpoint each point of the string rotates in the Y Z plane with an additional phase F due to direction changes of axes Y and Z in space and time. Continuously performing active Poincar´e transformations on the standing wave u(x, t) and not affecting the function F we obtain the function for the forced oscillations of a special kind U(x, t) = Ψ(x, t) cos Φ(x, t), where Ψ= exp (iS(x, t)). The phase Φ(x, t) = 0 is called “particle”. It is shown that S is the action of this particle. The particle total energy and generalized momentum that include the potential functions V, A are derived from S. Ψ reduces to an identity the Schrödinger equation with nonlocal Hamiltonian that contains the functions V, A. The identity remains valid when replacing the F with F − f(x, t). This replacement is equivalent to a local gauge transformation in the form of simultaneous replacement of Ψ with exp (if(x, t))Ψ, of V with V −∂tf(x, t) and of A with A+∂xf(x, t). Thus, the investigated model has local gauge symmetry.DOI 10.14258/izvasu(2016)1-04

Observable states are gauge-invariant. In a non-Abelian gauge theory, these are necessarily composite operators. We investigate the spectrum of these operators in the two-Higgs-doublet model. For this purpose, we are working along the lines of the Fr\"ohlich-Morchio-Strocchi mechanism to relate the physical spectrum to the spectrum of the elementary particles. We also investigate the consequences of spontaneous breaking of the global (custodial) symmetry group. Finally, we briefly comment on how to test the results using lattice methods., Comment: 21 pages, v2:minor changes, version to appear in PRD

We propose a novel general approach to locality of lattice composite fields, which in case of QCD involves locality in both quark and gauge degrees of freedom. The method is applied to gauge operators based on the overlap Dirac matrix elements, showing for the first time their local nature on realistic path-integral backgrounds. The framework entails a method for efficient evaluation of such non-ultralocal operators, whose computational cost is volume-indepenent at fixed accuracy, and only grows logarithmically as this accuracy approaches zero. This makes computation of useful operators, such as overlap-based topological density, practical. The key notion underlying these features is that of exponential insensitivity to distant fields, made rigorous by introducing the procedure of statistical regularization. The scales associated with insensitivity property are useful characteristics of non-local continuum operators., Comment: 34 pages, 10 figures; v2: published version with few remarks added

A new method to solve the Dirac equation on a 3D lattice is proposed, in which the variational collapse problem is avoided by the inverse Hamiltonian method and the fermion doubling problem is avoided by performing spatial derivatives in momentum space with the help of the discrete Fourier transform, i.e., the spectral method. This method is demonstrated in solving the Dirac equation for a given spherical potential in 3D lattice space. In comparison with the results obtained by the shooting method, the differences in single particle energy are smaller than $10^{-4}$~MeV, and the densities are almost identical, which demonstrates the high accuracy of the present method. The results obtained by applying this method without any modification to solve the Dirac equations for an axial deformed, non-axial deformed, and octupole deformed potential are provided and discussed., Comment: 18 pages, 6 figures

In this article, we explore the low energy structure of a $U(3)$ gauge theory over spaces with fuzzy sphere(s) as extra dimensions. In particular, we determine the equivariant parametrization of the gauge fields, which transform either invariantly or as vectors under the combined action of $SU(2)$ rotations of the fuzzy spheres and those $U(3)$ gauge transformations generated by $SU(2) \subset U(3)$ carrying the spin $1$ irreducible representation of $SU(2)$. The cases of a single fuzzy sphere $S_F^2$ and a particular direct sum of concentric fuzzy spheres, $S_F^{2 \, Int}$, covering the monopole bundle sectors with windings $\pm 1$ are treated in full and the low energy degrees of freedom for the gauge fields are obtained. Employing the parametrizations of the fields in the former case, we determine a low energy action by tracing over the fuzzy sphere and show that the emerging model is abelian Higgs type with $U(1) \times U(1)$ gauge symmetry and possess vortex solutions on ${\mathbb R}^2$, which we discuss in some detail. Generalization of our formulation to the equivariant parametrization of gauge fields in $U(n)$ theories is also briefly addressed., Comment: 27+1 pages

We present numerical details of the evaluation of the so-called Bose-ghost propagator in lattice minimal Landau gauge, for the SU(2) case in four Euclidean dimensions. This quantity has been proposed as a carrier of the confining force in the Gribov-Zwanziger approach and, as such, its infrared behavior could be relevant for the understanding of color confinement in Yang-Mills theories. Also, its nonzero value can be interpreted as direct evidence of BRST-symmetry breaking, which is induced when restricting the functional measure to the first Gribov region Omega. Our simulations are done for lattice volumes up to 120^4 and for physical lattice extents up to 13.5 fm. We investigate the infinite-volume and continuum limits., Comment: 14 pages, 6 tables, 13 figures (16 plots)

Toroidally compactified Yang-Mills theory on the lattice is studied by using the Hybrid Monte Carlo algorithm. When the compact dimensions are small, the theory naturally reduces to Yang-Mills with scalars. We confirm previous analytical and numerical results for pure gauge theory with scalars in (0+1) dimensions and at high temperatures to Super-Yang-Mills in (1+1) dimensions. In (1+1) dimensions, our simulations confirm the previously conjectured phase diagram. Furthermore, we find evidence for the sequential breaking of the center symmetry in (1+1) dimensions as a function of the volume. In (3+1) dimensions we present first simulation results for the eigenvalue distribution of the Polyakov and Wilson loops, finding localized, non-uniform and center-symmetric configurations as a function of the lattice coupling., Comment: 30 pages, 13 figures; v2: minor changes; v3: minor changes

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 pertubative 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 $\mathbb{Z}_{3}$ 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.

The three gluon one particle irreducible function is investigated using lattice QCD simulations over a large region of momentum in the Landau gauge for four dimensional pure Yang-Mills equations and the SU(3) gauge group. The results favor a zero crossing of the gluon form factor for momenta in the range $220 - 260$ MeV. This zero crossing is required to happen in order to have a properly defined set of Dyson-Schwinger equations. It is also shown that in the high momentum region the lattice results are compatible with the predictions of renormalisation group improved perturbation theory., Comment: 8 pages, 6 figures

We study the behavior of center sectors in pure SU(4) lattice gauge theory at finite temperature. The center sectors are defined as spatial clusters of neighboring sites with values of their local Polyakov loops near the same center elements. We study the connectedness and percolation properties of the center clusters across the deconfinement transition. We show that for SU(4) gauge theory deconfinement cannot be described as a percolation transition of center clusters, a finding which is different from pure SU(2) or pure SU(3) Yang Mills theory, where the percolation description even allows for a continuum limit., Comment: Three figures and discussion added. Final version to appear in Physics Letters B

The nature of the set of free fields that represent the system at the critical point has been revealed by studying the correlation functions of the degrees of freedom of the gauge supersymmetric Ising model on the cubic lattice. The same set of free fields represents the continuous supersymmetric Abelian gauge theory. Thus, the name of the lattice system is appropriate. Comparison with the two-dimensional Ising model is given.

The paper investigates the spontaneous breaking of gauge symmetries in gauge theories from a philosophical angle. Local gauge symmetry itself cannot break spontaneously in quantized gauge theories according to Elitzur's theorem---even though the notion of a spontaneously broken local gauge symmetry is widely employed in textbook expositions of the Higgs mechanism, the standard account of mass generation for the weak gauge bosons in the standard model. Nevertheless, gauge symmetry can be broken in gauge theories, namely, in the form of the breaking of remnant subgroups of the original local gauge group under which the theories typically remain invariant after gauge fixing. The paper discusses the relation between these instances of symmetry breaking and phase transitions and draws some more general conclusions for the philosophical interpretation of gauge symmetries and their breaking.

A general method for treating non-Gaussian wave functionals in quantum field theory is presented and applied to the Hamiltonian approach to Yang–Mills theory in Coulomb gauge in order to include a three-gluon kernel in the exponential of the vacuum wave functional. The three-gluon and ghost–gluon vertices are calculated using the propagators found in the variational approach with a Gaussian trial wave functional as input.

In this Letter we use the Julia–Toulouse approach for condensation of defects in order to obtain an effective confinement theory for external chromoelectric probe charges in SU ( 3 ) gauge theory in the regime with condensed chromomagnetic monopoles. We use the Cho decomposition of the non-Abelian connection in order to reveal the Abelian sector of the non-Abelian gauge theory and the associated topological defects (monopoles) without resorting to any gauge fixing procedure. Using only the Abelian sector of the theory, we construct a hydrodynamic effective theory for the regime with condensed defects in such a way that it is compatible with the Elitzurʼs theorem. The resulting effective theory describes the interaction between external chromoelectric probe charges displaying a short-range Yukawa interaction plus a linear confining term that governs the long distance physics.

I will review results obtained recently within the Hamilton approach to QCD in Coulomb gauge.

Generating functions of BPS invariants for $\CN=4$ $U(r)$ gauge theory on aHirzebruch surface with $r\leq 3$ are computed. The BPS invariantsprovide the Betti numbers of moduli spaces of semi-stable sheaves.The generating functions for $r=2$ are expressed in terms of higher level Appellfunctions for a certain polarization of the surface. The level corresponds to the self-intersection of the basecurve of the Hirzebruch surface. The non-holomorphic functions aredetermined, which added to the holomorphic generating functions providefunctions, which transform as a modular form.

We generalize the two-loop renormalization group equations for the parameters of the softly broken SUSY gauge theories given in the literature to the most general case when the gauge group contains more than a single Abelian gauge factor. The complete method is illustrated at two-loop within a specific example and compared to some of the previously proposed partial treatments.

Generalized Hamiltonian model can give dynamics mechanism of inner parameters connected, however, it will meet many difficult while an actual physical system is converted to Generalized Hamiltonian model. And due to complexity of the structure matrix and damping matrix of high order Hamiltonian system, analysis and application to inner parameters connected mechanism is not ease and convenience. In this paper one kind of Hamiltonian model, four order and single input affine nonlinear system, is given basic form, it is a formulation formulize form, that is generalize Hamiltonian model can be directly derived by formulate calculation. The hydro turbine Hamiltonian model is taken as case to introduce this modeling method. At last, a simulation simplified method based-physical background is proposed, and used to simplify the hydro turbine Hamiltonian model.

In analogy to the pions in chiral perturbation theory, the transverse fluctuations of a confining string in Yang–Mills theory are described by a systematic low-energy effective field theory. The predictions of the effective theory at the two-loop level are in quantitative agreement with high-precision Monte Carlo data obtained from lattice gauge theory. The decay and ultimate breaking of strings connecting charges in higher-dimensional representations of the gauge group are also investigated.

The Dyson-Schwinger equation for the ghost-gluon vertex of the Hamiltonian approach to Yang-Mills theory in Coulomb gauge is solved at one-loop level using as input the non-perturbative ghost and gluon propagators previously determined within the variational approach. The obtained ghost-gluon vertex is IR finite but IR enhanced compared to the bare one by 15% to 25%, depending on the kinematical momentum regime., Comment: 7 pages, 5 eps figures

Vacuum characteristics quantifying dynamical tendency toward self-duality in gauge theories could be used to judge the relevance of classical solutions or the viability of classically motivated vacuum models. Here we decompose the field strength of equilibrium gauge configurations into self-dual and anti-self-dual parts, and apply absolute X-distribution method to the resulting polarization dynamics in order to construct such characteristics. Using lattice regularization and focusing on pure-glue SU(3) gauge theory at zero temperature, we find evidence for positive but very small dynamical tendency for self-duality of vacuum in the continuum limit., Comment: 11 pages, 4 figures

We derive constraints on the color-ordered amplitudes of the L-loop four-point function in SU(N) gauge theories that arise solely from the structure of the gauge group. These constraints generalize well-known group theory relations, such as U(1) decoupling identities, to all loop orders., 12 pages, no figures; v2: added references, minor corrections; v3: minor clarifications, published version

Hamiltonian function is different, the internal structure relation given by generalized Hamiltonian model is different, and thus Hamiltonian function is core issue for generalized Hamiltonian modeling. In this paper, three principles of selecting Hamiltonian function are proposed, interface principle, energy principle and stability principle. For the class of system with single input and single output, applied methods of three principles are given. At last, the Hamiltonian modelling for nonlinear hydro turbine is taken as case to introduce its application.

Recently we have studied the instant-form quantization (IFQ) and the light-front quantization (LFQ) of the conformally gauge-fixed Polyakov D1 brane action using the Hamiltonian and path integral formulations. The IFQ is studied in the equal world-sheet time framework on the hyperplanes defined by the world- sheet time σ0 = τ = constant and the LFQ in the equal light-cone world-sheet time framework, on the hyperplanes of the light-front defined by the light-cone world-sheet time . The light-front theory is seen to be a constrained system in the sense of Dirac in contrast to the instant-form theory. However, owing to the gauge anomalous nature of these theories, both of these theories are seen to lack the usual string gauge symmetries defined by the world-sheet reparametrization invariance (WSRI) and the Weyl invariance (WI). In the present work we show that these theories when considered in the presence of background gauge fields such as the NSNS 2-form gauge field or in the presence of gauge field and the constant scalar axion field , then they are seen to possess the usual string gauge symmetries (WSRI and WI). In fact, these background gauge fields are seen to behave as the Wess-Zumino/Stueckelberg fields and the terms containing these fields are seen to behave as Wess-Zumino or Stueckelberg terms for these theories.

Kalb-Ramond gauge theory on a \(D_5\)-brane in presence of a background open string metric is studied to construct a geometric torsion in a second order formalism. Interestingly, an absorption of KR field in the CFT is shown to describe a vacuum created gravitational pair of \((4{\bar{4}})\)-brane underlying an effective torsion curvature in space-time. We obtain quantum Schwarzschild like geometries in the string-brane setup. In a low energy limit a quantum black hole is shown to describe the Einstein vacuum.

We propose a digital quantum simulator of non-Abelian pure-gauge models with a superconducting circuit setup. Within the framework of quantum link models, we build a minimal instance of a pure $SU(2)$ gauge theory, using triangular plaquettes involving geometric frustration. This realization is the least demanding, in terms of quantum simulation resources, of a non-Abelian gauge dynamics. We present two superconducting architectures that can host the quantum simulation, estimating the requirements needed to run possible experiments. The proposal establishes a path to the experimental simulation of non-Abelian physics with solid-state quantum platforms.

We investigate the low energy continuum limit theory for electrons in a graphene sheet under strain. We use the quantum field theory in curved spaces to analyze the effect of the system deformations into an effective gauge field. We study both in-plane and out-of-plane deformations and obtain a closed expression for the effective gauge field due to arbitrary nonuniform sheet deformations. The obtained results reveal a remarkable relation between the local-pseudo magnetic field and the Riemann curvature, so far overlooked., 8 pages, 4 figures

The dynamics of symplectic gauge fields provides a consistent framework for fundamental interactions based on spin three gauge fields. One remarkable property is that symplectic gauge fields only have minimal couplings with gravitational fields and not with any other field of the Standard Model. Interactions with ordinary matter and radiation can only arise from radiative corrections. In spite of the gauge nature of symplectic fields they acquire a mass by the Coleman-Weinberg mechanism which generates Higgs-like mass terms where the gravitational field is playing the role of a Higgs field. Massive symplectic gauge fields weakly interacting with ordinary matter are natural candidates for the dark matter component of the Universe., Comment: 16 pages

The following is meant to give an overview over our special volume. The first three Sects. 1–3 are intended to give a general overview over the physical motivations behind this direction of research, and some of the developments that initiated this project.

In this note we continue to pursue the question whether gauge theories can be represented in terms of effective "scalar" degrees of freedom. We provide such a consistent representation for a free photon theory in 3+1 dimensions. Building on results of [1] we construct a Lagrangian with a four derivative kinetic term, and demonstrate that despite seeming nonlinearity of the theory it is equivalent to a theory of a free photon., 7 pages

In this letter, we revise the QED gauge invariance for the hadron tensor of Drell-Yan type processes with the transversely polarized hadron. We perform our analysis within the Feynman gauge for gluons and make a comparison with the results obtained within the light-cone gauge. We demonstrate that QED gauge invariance leads, first, to the need of a non-standard diagram and, second, to the absence of gluon poles in the correlators $\langle\bar\psi\gamma_\perp A^+\psi\rangle$ related traditionally to $dT(x,x)/dx$. As a result, these terms disappear from the final QED gauge invariant hadron tensor. We also verify the absence of such poles by analysing the corresponding light-cone Dirac algebra., Comment: 5 pages, 2 figures. The improved version. Accepted for publication in PLB

The equivalence between a higher derivative extension of Maxwell–Chern–Simons–Proca model and some gauge invariant theories from the point of view of the Hamiltonian path integral quantization in the framework of the gauge-unfixing approach is investigated. The Hamiltonian path integrals of the first-class systems take manifestly Lorentz-covariant forms.

This chapter discusses how to treat the case of a perturbation which depends on time. It also discusses the case of the so-called real-time evolution and the adiabatic process which has received more recent attention because of experiments on quantum dynamics in trapped cold atoms.

A minimal quasiparticle approach for describing QGP at temperatures much higher than the critical one is discussed. It involves an ideal-gas framework in which quark and gluon masses depend on temperature. This model is able to reproduce the recent equations of state computed in lattice QCD for temperatures typically higher than 2 Tc, in a range in which it is reasonable to neglect interactions between quasiparticles. In addition, the equations of state for a generic gauge theory with gauge groups SU(Nc) and quarks in an arbitrary representation are studied. The gauge independence in the pure glue sector and the large-Nc equivalence between the gauge groups SU(Nc) and SO(2Nc) in a full plasma is finally shown for normalized thermodynamic quantities.

We study an SU(2) lattice gauge field system on a 104 symmetric and on a 103 × 2 asymmetric lattice in order to learn about the equation of state.

An explicitly gauge invariant strong field theory is introduced and tested using a model laser-atom interaction. The theory relies on a power series in the target potential. Transitions amplitudes are obtained by using a corresponding series in the momentum space wave function. We demonstrate that this approach is explicitly gauge invariant to all orders. A well know 1D delta function potential model is used to test the convergence of the series in the evaluation of total ionization probabilities and ionization spectra. Actually, the convergence is verified when both, the perturbation as well as the order of the expansion, are increased. © 2011 EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg. Fil: Rodríguez Chariarse, Vladimir Daniel. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentina Fil: Barrachina Tejada, Raul Oscar. Universidad Nacional de Cuyo; Argentina

We compute the expectation values of both the time-like and the light-like Wilson loops in a strongly coupled plasma of ( p + 1 ) -dimensional Yang–Mills theories using gravity/gauge theory correspondence. From the time-like Wilson loop we obtain the velocity dependent quark–antiquark potential where the dipole is moving through the plasma with an arbitrary velocity 0 v 1 and also obtain expressions for the screening lengths. When the velocity v → 1 , the Wilson loop becomes light-like and we obtain the form of the jet quenching parameter in those strongly coupled plasma.

A ternary gauge field theory is explicitly constructed based on a totally antisymmetric ternary-bracket structure associated with a 3-Lie algebra. It is shown that the ternary infinitesimal gauge transformations do obey the key closure relations [δ1, δ2] = δ3. Invariant actions for the 3-Lie algebra-valued gauge fields and scalar fields are displayed. We analyze and point out the difficulties in formulating a nonassociative octonionic ternary gauge field theory based on a ternary-bracket associated with the octonion algebra and defined earlier by Yamazaki. It is shown that a Yang–Mills-like quadratic action is invariant under global (rigid) transformations involving the Yamazaki ternary octonionic bracket, and that there is closure of these global (rigid) transformations based on constant antisymmetric parameters Λab = - Λba. Promoting the latter parameters to space–time dependent ones Λab(xμ) allows one to build an octonionic ternary gauge field theory when one imposes gauge covariant constraints on the latter gauge parameters leading to field-dependent gauge parameters and nonlinear gauge transformations. In this fashion one does not spoil the gauge invariance of the quadratic action under this restricted set of gauge transformations and which are tantamount to space–time dependent scalings (homothecy) of the gauge fields.

Two different gauge potential methods are engaged to calculate explicitly the spin Hall conductivity in graphene. The graphene Hamiltonian with spin-orbit interaction is expressed in terms of kinematic momenta by introducing a gauge potential. A formulation of the spin Hall conductivity is established by requiring that the time evolution of this kinematic momentum vector vanishes. We then calculated the conductivity employing the Berry gauge fields. We show that both of the gauge fields can be deduced from the pure gauge field arising from the Foldy-Wouthuysen transformations., Presentation improved. Published version

The Hamiltonian reduction of the Yang-Mills theory with the structure group SU(2) to a nonlocal model of a self-interacting 3 × 3 positive semidefinite matrix field is presented. Analysis of the field transformation properties under the action of the Poincare group is carried out. It is shown that, in the strong coupling limit, the classical dynamics of a reduced system can be described by the local theory of interacting nonrelativistic spin-0 and spin-2 fields. A perturbation theory in powers of the inverse coupling constant g−2/3 that allows calculating the corrections to a leading long-wave approximation is suggested.

We summarize the activities of the lattice gauge theory section of the working group activities in non-perturbative QCD.

We discuss the interpretation of the three-dimensional N = 8 superconformal Chern-Simons-matter theory with the gauge group of volume preserving diffeomorphisms as a model describing a six-dimensional self-dual gauge field coupled to scalars and spinors and its possible relation to the M5-brane

This talk discusses methods of extending lattice computations at finite temperature into regions of finite chemical potential, and the conditions under which such results from the lattice may be compared to experiments. Such comparisons away from a critical point are absolutely essential for quantitative use of lattice QCD in heavy-ion physics. An outline of various arguments which can then be used to locate the critical point is also presented.