scholarly journals Strong anomaly and phases of chiral gauge theories

2021 ◽  
Vol 2021 (8) ◽  
Author(s):  
Stefano Bolognesi ◽  
Kenichi Konishi ◽  
Andrea Luzio
Keyword(s):  
Large Class ◽  
Effective Action ◽  
Degrees Of Freedom ◽  
Gauge Theories ◽  
Low Energy ◽  
Composite Fermions ◽  
Simple Argument ◽  
Strongly Coupled ◽  
Basic Criterion ◽  
The One

Abstract We present a simple argument which seems to favor, when applied to a large class of strongly-coupled chiral gauge theories, a dynamical-Higgs-phase scenario, characterized by certain bifermion condensates. Flavor symmetric confining vacua described in the infrared by a set of baryonlike massless composite fermions saturating the conventional ’t Hooft anomaly matching equations, appear instead disfavored. Our basic criterion is that it should be possible to write a strong-anomaly effective action, analogous to the one used in QCD to describe the solution of the U(1)A problem in the low-energy effective action, by using the low-energy degrees of freedom in the hypothesized infrared theory. We also comment on some well-known ideas such as the complementarity and the large N planar dominance in the context of these chiral gauge theories. Some striking analogies and contrasts between the massless QCD and chiral gauge theories seem to emerge from this discussion.

scholarly journals On the component structure of one-loop effective actions in 6D, 𝒩 = (1,0) and 𝒩 = (1,1) supersymmetric gauge theories

2019 ◽  
Vol 35 (09) ◽  
pp. 2050060 ◽  
Author(s):  
I. L. Buchbinder ◽  
A. S. Budekhina ◽  
B. S. Merzlikin
Keyword(s):  
Effective Potential ◽  
Effective Action ◽  
Gauge Theories ◽  
Scalar Fields ◽  
Low Energy ◽  
Supersymmetric Gauge Theories ◽  
Component Structure ◽  
Yang Mills ◽  
Supersymmetric Gauge ◽  
The One

We study the six-dimensional [Formula: see text] and [Formula: see text] supersymmetric Yang–Mills (SYM) theories in the component formulation. The one-loop divergencies of effective action are calculated. The leading one-loop low-energy contributions to bosonic sector of effective action are found. It is explicitly demonstrated that the contributions to effective potential for the constant background scalar fields are absent in the [Formula: see text] SYM theory.

scholarly journals STRONGLY COUPLED N=1 SUPERSYMMETRIC SO(Nc) GAUGE THEORIES WITHOUT MAGNETIC DEGREES OF FREEDOM

2004 ◽  
Vol 19 (25) ◽  
pp. 4323-4354
Author(s):  
MASAKI YASUÈ
Keyword(s):  
Symmetry Breaking ◽  
Degrees Of Freedom ◽  
Gauge Theories ◽  
Low Energy ◽  
Flavor Symmetry ◽  
Correct Description ◽  
Strongly Coupled ◽  
Energy Physics

In strongly coupled supersymmetric SO (Nc) gauge theories with Nf-quarks for Nc-2≤Nf(≤3(Nc-2)/2), their low-energy physics can be described by Nambu–Goldstone superfields associated with dynamical flavor symmetry breaking, which should be compared with the absence of flavor symmetry breaking in the conventional description in terms of magnetic degrees of freedom. The presence of the flavor symmetry breaking is confirmed by the well-known instanton effects in SO (Nc) with Nf=Nc-2, which are also described by our proposed effective superpotential. For Nf≥Nc-1, our effective superpotentials utilize baryonic configurations as well as mesons composed of two quarks. The baryonic configurations are supplied by "diquarks" made of Nc-1 quarks for Nf=Nc-1 and by baryons composed of Nc quarks for Nc≥Nf. It is argued that our effective superpotentials exhibit the holomorphic decoupling property, the anomaly-matching property and correct description of instanton effects in SO (Nc) when Nf-Nc+2 quarks become massive if Nf≥Nc-1.

scholarly journals MAGNETIC ZN SYMMETRY IN 2+1 DIMENSIONS

2002 ◽  
Vol 17 (16) ◽  
pp. 2113-2164 ◽  
Author(s):  
A. KOVNER
Keyword(s):  
Degrees Of Freedom ◽  
Gauge Theories ◽  
Chiral Symmetry Breaking ◽  
Low Energy ◽  
Effective Theory ◽  
Spontaneous Breaking ◽  
Range Interaction ◽  
Strongly Coupled ◽  
Effective Lagrangian ◽  
Magnetic Symmetry

This review describes the role of magnetic symmetry in (2+1)-dimensional gauge theories. In confining theories without matter fields in fundamental representation the magnetic symmetry is spontaneously broken. Under some mild assumptions, the low-energy dynamics is determined universally by this spontaneous breaking phenomenon. The degrees of freedom in the effective theory are magnetic vortices. Their role in confining dynamics is similar to that played by pions and σ in the chiral symmetry breaking dynamics. I give an explicit derivation of the effective theory in (2+1)-dimensional weakly coupled confining models and argue that it remains qualitatively the same in strongly coupled (2+1)-dimensional gluodynamics. Confinement in this effective theory is a very simple classical statement about the long range interaction between topological solitons, which follows (as a result of a simple direct classical calculation) from the structure of the effective Lagrangian. I show that if fundamentally charged dynamical fields are present the magnetic symmetry becomes local rather than global. The modifications to the effective low energy description in the case of heavy dynamical fundamental matter are discussed. This effective Lagrangian naturally yields a bag like description of baryonic excitations. I also discuss the fate of the magnetic symmetry in gauge theories with the Chern–Simons term.

scholarly journals Quantum information probes of charge fractionalization in large-N gauge theories

2021 ◽  
Vol 2021 (5) ◽  
Author(s):  
Brandon S. DiNunno ◽  
Niko Jokela ◽  
Juan F. Pedraza ◽  
Arttu Pönni
Keyword(s):  
Degrees Of Freedom ◽  
Gauge Theories ◽  
Entanglement Entropy ◽  
Coarse Grained ◽  
Strongly Coupled ◽  
Information Theoretic ◽  
Large N ◽  
Wide Range ◽  
Charge Fractionalization ◽  
Electric Flux

Abstract We study in detail various information theoretic quantities with the intent of distinguishing between different charged sectors in fractionalized states of large-N gauge theories. For concreteness, we focus on a simple holographic (2 + 1)-dimensional strongly coupled electron fluid whose charged states organize themselves into fractionalized and coherent patterns at sufficiently low temperatures. However, we expect that our results are quite generic and applicable to a wide range of systems, including non-holographic. The probes we consider include the entanglement entropy, mutual information, entanglement of purification and the butterfly velocity. The latter turns out to be particularly useful, given the universal connection between momentum and charge diffusion in the vicinity of a black hole horizon. The RT surfaces used to compute the above quantities, though, are largely insensitive to the electric flux in the bulk. To address this deficiency, we propose a generalized entanglement functional that is motivated through the Iyer-Wald formalism, applied to a gravity theory coupled to a U(1) gauge field. We argue that this functional gives rise to a coarse grained measure of entanglement in the boundary theory which is obtained by tracing over (part) of the fractionalized and cohesive charge degrees of freedom. Based on the above, we construct a candidate for an entropic c-function that accounts for the existence of bulk charges. We explore some of its general properties and their significance, and discuss how it can be used to efficiently account for charged degrees of freedom across different energy scales.

scholarly journals NONPERTURBATIVE EFFECTIVE ACTIONS OF (N=2)-SUPERSYMMETRIC GAUGE THEORIES

1996 ◽  
Vol 11 (11) ◽  
pp. 1929-1973 ◽  
Author(s):  
A. KLEMM ◽  
W. LERCHE ◽  
S. THEISEN
Keyword(s):  
Riemann Surface ◽  
Effective Action ◽  
Gauge Theories ◽  
Gauge Coupling ◽  
Low Energy ◽  
Yang Mills ◽  
Hyperelliptic Riemann Surface ◽  
Supersymmetric Gauge ◽  
Energy Quantum ◽  
Appell Functions

We elaborate on our previous work on (N=2)-supersymmetric Yang-Mills theory. In particular, we show how to explicitly determine the low energy quantum effective action for G=SU(3) from the underlying hyperelliptic Riemann surface, and calculate the leading instanton corrections. This is done by solving Picard-Fuchs equations and asymptotically evaluating period integrals. We find that the dynamics of the SU(3) theory is governed by an Appell system of type F4, and compute the exact quantum gauge coupling explicitly in terms of Appell functions.

scholarly journals On the alternative formulation of the three-dimensional noncommutative superspace

2016 ◽  
Vol 31 (10) ◽  
pp. 1650055 ◽  
Author(s):  
F. S. Gama ◽  
J. R. Nascimento ◽  
A. Yu. Petrov
Keyword(s):  
Effective Action ◽  
Three Dimensional ◽  
Low Energy ◽  
Alternative Formulation ◽  
Quantum Calculations ◽  
Point Function ◽  
The One ◽  
Chiral Superfield

In this paper, we propose a new version for the noncommutative superspace in 3D. This version is shown to be convenient for performing quantum calculations. In the paper, we use the theory of the chiral superfield as a prototype for possible generalizations, calculating the one-loop two-point function of a chiral superfield and the one-loop low-energy effective action in this theory.

scholarly journals ON LOW-ENERGY EFFECTIVE ACTION OF NONCOMMUTATIVE HYPERMULTIPLET MODEL

2001 ◽  
Vol 16 (40) ◽  
pp. 2591-2603 ◽  
Author(s):  
I. B. SAMSONOV
Keyword(s):  
Effective Action ◽  
Adjoint Representation ◽  
Low Energy ◽  
Coupling Constants ◽  
Quantum Corrections ◽  
Fundamental Representation ◽  
Harmonic Superspace ◽  
Commutative Case ◽  
The One ◽  
External Gauge

We consider the noncommutative hypermultiplet model within harmonic superspace approach. The one-loop four-point contributions to the effective action of self-interacting q-hypermultiplet are computed. This model has two coupling constants instead of a single one in commutative case. It is shown that both coupling constants are generated by one-loop quantum corrections in the model of q-hypermultiplet interacting with vector multiplet. The holomorphic effective action of q-hypermultiplet in external gauge superfield is calculated. For the fundamental representation there is no uv/ir-mixing and the holomorphic potential is a ⋆-product generalization of a standard commutative one. For the adjoint representation of U(N) gauge group the leading contributions to the holomorphic effective action are given by the terms respecting for the uv/ir-mixing which are related to U(1) phase of U(N) group.

scholarly journals Scalar field effective action for the spontaneous symmetry breaking in gravity

2019 ◽  
Vol 34 (20) ◽  
pp. 1950156
Author(s):  
Amin Akhavan
Keyword(s):  
Vector Field ◽  
Scalar Field ◽  
Symmetry Breaking ◽  
Path Integral ◽  
Effective Action ◽  
Degrees Of Freedom ◽  
Special Kind ◽  
Canonical Momentum ◽  
Massive Vector ◽  
The One

In this paper, we obtain the quantum effective action for a scalar field which has been used for a special kind of symmetry breaking in gravity. Precisely by making use of some renormalization conditions, we calculate the one-loop path integral of canonical momentum. Moreover, we show that by introducing some new renormalization conditions, one can redefine the new degrees of freedom corresponding to a massive vector field.

scholarly journals EFFECTIVE ACTION OF SPONTANEOUSLY BROKEN GAUGE THEORIES

1998 ◽  
Vol 13 (01) ◽  
pp. 95-124 ◽  
Author(s):  
S.-H. HENRY TYE ◽  
YAN VTOROV-KAREVSKY
Keyword(s):  
Effective Potential ◽  
Effective Action ◽  
Gauge Theories ◽  
Perturbation Expansion ◽  
Gauge Invariant ◽  
Abelian Case ◽  
Covariant Gauge ◽  
The One ◽  
Higgs Fields ◽  
Field Redefinition

The effective action of a Higgs theory should be gauge-invariant. However, the quantum and/or thermal contributions to the effective potential seem to be gauge-dependent, posing a problem for its physical interpretation. In this paper, we identify the source of the problem and argue that in a Higgs theory perturbative contributions should be evaluated with the Higgs fields in the polar basis, not in the Cartesian basis. Formally, this observation can be made from the derivation of the Higgs theorem, which we provide. We show explicitly that, properly defined, the effective action for the Abelian Higgs theory is gauge-invariant to all orders in perturbation expansion when evaluated in the covariant gauge in the polar basis. In particular, the effective potential is gauge-invariant. We also show the equivalence between the calculations in the covariant gauge in the polar basis and the unitary gauge. These points are illustrated explicitly with the one-loop calculations of the effective action. With a field redefinition, we obtain the physical effective potential. The SU(2) non-Abelian case is also discussed.

scholarly journals Harmonic Superspace Approach to the Effective Action in Six-Dimensional Supersymmetric Gauge Theories

Symmetry ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 68 ◽  
Author(s):  
Ioseph Buchbinder ◽  
Evgeny Ivanov ◽  
Boris Merzlikin ◽  
Konstantin Stepanyantz
Keyword(s):  
Effective Action ◽  
Gauge Theories ◽  
Proper Time ◽  
Background Field ◽  
Field Method ◽  
Quantum Corrections ◽  
Supersymmetric Gauge Theories ◽  
Loop Approximation ◽  
Supersymmetric Gauge ◽  
The One

We review the recent progress in studying the quantum structure of 6 D , N = ( 1 , 0 ) , and N = ( 1 , 1 ) supersymmetric gauge theories formulated through unconstrained harmonic superfields. The harmonic superfield approach allows one to carry out the quantization and calculations of the quantum corrections in a manifestly N = ( 1 , 0 ) supersymmetric way. The quantum effective action is constructed with the help of the background field method that secures the manifest gauge invariance of the results. Although the theories under consideration are not renormalizable, the extended supersymmetry essentially improves the ultraviolet behavior of the lowest-order loops. The N = ( 1 , 1 ) supersymmetric Yang–Mills theory turns out to be finite in the one-loop approximation in the minimal gauge. Furthermore, some two-loop divergences are shown to be absent in this theory. Analysis of the divergences is performed both in terms of harmonic supergraphs and by the manifestly gauge covariant superfield proper-time method. The finite one-loop leading low-energy effective action is calculated and analyzed. Furthermore, in the Abelian case, we discuss the gauge dependence of the quantum corrections and present its precise form for the one-loop divergent part of the effective action.

Sign in / Sign up

Export Citation Format

Share Document