From 3d dualities to hadron physics

TL;DR

This paper explores the phase transitions and topological phases in compactified QCD, proposing a dual gauge theory involving mesons near the critical point, and connecting it to level-rank duality in 3D gauge theories.

Contribution

It introduces a novel scenario where mesons form a $U(N_f)$ gauge theory near the critical point, linking chiral symmetry restoration to dual gauge bosons via level-rank duality.

Findings

Identification of topological ordered phase at low energy with a background $ heta$ term.

Proposal of a $U(N_f)$ gauge theory involving mesons near the critical point.

Connection of meson duality to level-rank duality between $SU(N)_{N_f}$ and $U(N_f)_{-N}$ gauge theories.

Abstract

When one of the space-time dimension is compactified on $S^1$, the QCD exhibits the chiral phase transition at some critical radius. When we further turn on a background $\theta$ term which depends on the $S^1$ compactified coordinate, a topological ordered phase appears at low energy via the winding of $\theta$. We discuss what kind of theories can describe the physics near the critical point by requiring the matching of topological field theories in the infrared. As one of the possibilities, we propose a scenario where the $\rho$ and $\omega$ mesons form a $U(N_f)$ gauge theory near the critical point. In the phase where the chiral symmetry is restored, they become the dual gauge boson of the gluon related by the level-rank duality between the three dimensional gauge theories, $SU(N)_{N_f}$ and $U(N_f)_{-N}$.