Related papers: $\theta=\pi$ in $SU(N)/\mathbb{Z}_N$ gauge theorie…
Recent studies on the 't Hooft anomaly matching condition have suggested a nontrivial phase structure in 4D SU($N$) gauge theory at $\theta=\pi$. In the large-$N$ limit, it has been found that CP symmetry at $\theta=\pi$ is broken in the…
$SU(N)$ gauge theory is time reversal invariant at $\theta=0$ and $\theta=\pi$. We show that at $\theta=\pi$ there is a discrete 't Hooft anomaly involving time reversal and the center symmetry. This anomaly leads to constraints on the…
The spontaneous breaking of CP symmetry in 4D SU($N$) pure Yang-Mills theory at $\theta=\pi$ has recently attracted much attention in the context of the higher-form symmetry and the 't Hooft anomaly matching condition. Here we use Monte…
Assuming that a quantum field theory with a $\theta$-vacuum term in the action shows non-trivial $\theta$-dependence and provided that some reasonable properties of the probability distribution function of the order parameter hold, we argue…
It has been speculated that the CP symmetry of 4D SU(3) Yang-Mills theory at $\theta=\pi$ is spontaneously broken in the confined phase, and it is recovered precisely at the deconfining temperature. The direct simulation of the theory at…
We discuss the deconfinement and the CP-breaking phase transitions at $\theta=\pi$ in Yang-Mills theories. The 't Hooft anomaly matching prohibits the confined phase with CP symmetry and requires $T_{dec}(\theta=\pi) \le T_{CP}$, where…
We consider gauge theories of non-Abelian $finite$ groups, and discuss the 1+1 dimensional lattice gauge theory of the permutation group $S_N$ as an illustrative example. The partition function at finite $N$ can be written explicitly in a…
We investigate the possibility of the spontaneous breaking of CP symmetry in 4D SU(2) Yang-Mills at $\theta=\pi$, which has recently attracted much attention in the context of the higher-form symmetry and the 't Hooft anomaly matching…
We investigate the dependence of four-dimensional SU(N) gauge theories on the topological theta term at finite temperature and, in particular, across the deconfinement transition. For this purpose, we exploit the lattice formulation of the…
We explore 4-dimensional SU(N) gauge theory with a Weyl fermion in an irreducible self-conjugate representation. This theory, in general, has a discrete chiral symmetry. We use 't Hooft anomaly matching condition of the center symmetry and…
By using the standard perturbation theory we study the mass as well as $\theta$ parameter dependence of the Seiberg-Witten theory with $SU(2)$ gauge group, supplemented with a $N=1$ supersymmetric as well as a smaller nonsupersymmetric…
We examine the phase structure of a QCD-like theory at $\bar\theta =\pi$ obtained from supersymmetric $SU(N)$ QCD perturbed by a small amount of supersymmetry breaking via anomaly mediation (AMSB QCD). The spectrum of this theory matches…
The theta dependent of pure gauge theories in four dimensions can be studied using a duality of large N gauge theories with string theory on a certain spacetime. Via this duality, one can argue that for every theta, there are infinitely…
We present recent results on the theta-dependence of four-dimensional SU(N) gauge theories, where theta is the coefficient of the CP-violating topological term in the Lagrangian. In particular, we study the scaling behavior of these…
We study the large-$N$ scaling behavior of the $\theta$ dependence of the ground-state energy density $E(\theta)$ of four-dimensional (4D) $SU(N)$ gauge theories and two-dimensional (2D) $CP^{N-1}$ models, where $\theta$ is the parameter…
We study the phase diagram of an $SU(N)$ gauge theory in terms of the number of colors $N$ and flavors $N_f$ with emphasis on the confinement and chiral symmetry breaking phases. We argue that as opposed to SUSY QCD there is a small region…
Symmetries in Quantum Field Theory may have 't Hooft anomalies. If the symmetry is unbroken in the vacuum, the anomaly implies a nontrivial low-energy limit, such as gapless modes or a topological field theory. If the symmetry is…
The phase structure of QCD-like gauge theories with fermions in various representations is an interesting but generally analytically intractable problem. One way to ensure weak coupling is to define the theory in a small finite volume, in…
We review recent results on the theta dependence of the ground-state energy and spectrum of four-dimensional SU(N) gauge theories, where theta is the coefficient of the CP-violating topological term F-Fdual in the Lagrangian. In particular,…
We calculate the $\theta$ dependence in a cousin of QCD, where the vacuum structure can be analyzed exactly. The theory is $\mathcal{N}=2$ $SU(2)$ gauge theory with $N_F=0,1,2,3$ flavors of fundamentals, explicitly broken to $\mathcal{N}=1$…