Related papers: Axial Anomaly in the $SU(N)$ Gauge Matrix Model
We study fermions derivatively coupled to axion-like or pseudoscalar fields, and show that the axial vector current of the fermions is not conserved in the limit where the fermion is massless. This apparent violation of the classical chiral…
We critically reconsider the argument based on 't Hooft anomaly matching that aims at proving chiral symmetry breaking in confining four-dimensional QCD-like theories with $N_c>2$ colors and $N_f$ flavors. The main line of reasoning relies…
We propose a six-dimensional regularization of four dimensional chiral gauge theories. We consider a massive Dirac fermion in six dimensions with two different operators having domain-wall profiles in the fifth and the sixth directions,…
We propose a novel modular anomaly equation for the unflavored Schur index in the $\mathcal{N}=4$ $SU(N)$ super-Yang-Mills theory. The vanishing conditions overdetermine the modular ambiguity ansatz from the equation, thus together they are…
We investigate the nature of the finite-temperature chiral transition in QCD with two light flavors, in the case of an effective suppression of the the U(1)_A symmetry breaking induced by the axial anomaly, which implies the symmetry…
It is shown that parity operator plays an interesting role in Dirac equation in (1+2) dimensions and can be used for defining chiral currents. It is shown that the "anomalous" current induced by an external gauge field can be related to the…
Chiral quark model with a broken-U(3) flavor symmetry can be interpreted as the effective theory of the instanton-dominated non-perturbative QCD. This naturally suggests the possibility of a negative singlet/octet coupling ratio, which has…
We study the strong-interaction dynamics of a class of $4D$ chiral $SU(N)$ gauge theories with a fermion in a symmetric second-rank tensor representation and a number of fermions in an anti-antisymmetric tensor representation, extending the…
We find a large class of quantum gauge models with massless fermions where the coupling to the gauge fields is not chirally symmetric and which nevertheless do not suffer from gauge anomalies. To be specific we study two dimensional Abelian…
Recently $SU(2)$ Yang-Mills theory with one massless adjoint Dirac quark flavor emerges as a novel critical theory that can describe the evolution between a trivial insulator and a topological insulator in AIII class in $3+1$ dimensions.…
The flavor SU(3)_f group symmetry of QCD is systematically considered as the heavy c quark limit of SU(4)_f. Within that scheme we argue that the U(1)_A anomaly prevents Gell-Mann's choice for the realization of the su(4)_f (and thereby the…
We present exact results in softly-broken supersymmetric $\text{SU}(N_C)$ chiral gauge theories with charged fermions in one antisymmetric, $N_F$ fundamental, and $N_C+N_F-4$ anti-fundamental representations. We achieve this by considering…
The symmetry breaking pattern of QCD features two seemingly disconnected phenomena: the spontaneous breakdown of the Z(3) center symmetry in the deconfinement transition of pure-gauge QCD, and the spontaneous breaking of chiral…
We present a study of spectroscopy of SU(4) lattice gauge theory coupled to two flavors of Dirac fermions in the anti-symmetric two index representation. The fermion representation is real, and the pattern of chiral symmetry breaking is…
The dynamics at the IR fixed point realized in the $SU(N_c)$ gauge theories with massless Dirac fermions is studied by means of the non-perturbative renormalization group. The analysis includes the IR fixed points with non-trivial Yukawa…
We study IR-renormalon divergences in N=1 supersymmetric Yang Mills gauge theories and in two dimensional non linear sigma models with mass gap. We derive, in both types of theories, a direct connection between IR- renormalons and…
We consider SU(N) Yang-Mills theories in 2n+1 Euclidean dimensions coupled to an even flavour-number of Dirac fermions. After integrating out the fermions the wave functional for the effective Yang-Mills theory inherits a non-trivial…
In order to clarify the connection between {\it current} and {\it constituent} quarks (of u,d,s flavors), several authors have used the lightlike chiral $SU(3)\otimes SU(3)$ algebra as a central concept. This literature is reviewed here…
We consider a U(1) gauge theory, minimally coupled to a massless Dirac field, where a higher-derivative term is added to the pure gauge sector, as in the Lee-Wick models. We find that this term can trigger chiral symmetry breaking at low…
The domain model for the QCD vacuum has previously been developed and shown to exhibit confinement of quarks and strong correlation of the local chirality of quark modes and duality of the background domain-like gluon field. Quark…