Phases of a two dimensional large N gauge theory on a torus

TL;DR

This paper analyzes the phase structure of a two-dimensional large N gauge theory on a torus, identifying phase boundaries, transition orders, and proposing a dual gravity description, connecting gauge theory and string theory insights.

Contribution

It provides a nonperturbative phase diagram of the 2D large N gauge theory on a torus using a 1/D expansion and links it to higher-dimensional Yang-Mills theories and gravity duals.

Findings

Identified phase boundaries and transition orders in the gauge theory.

Matched gauge theory phases with lattice calculations and gravity duals.

Proposed a gravity dual based on Scherk-Schwarz compactification.

Abstract

We consider two-dimensional large N gauge theory with D adjoint scalars on a torus, which is obtained from a D+2 dimensional pure Yang-Mills theory on T^{D+2} with D small radii. The two dimensional model has various phases characterized by the holonomy of the gauge field around non-contractible cycles of the 2-torus. We determine the phase boundaries and derive the order of the phase transitions using a method, developed in an earlier work (arxiv:0910.4526), which is nonperturbative in the 'tHooft coupling and uses a 1/D expansion. We embed our phase diagram in the more extensive phase structure of the D+2 dimensional Yang-Mills theory and match with the picture of a cascade of phase transitions found earlier in lattice calculations (arxiv:0710.0098). We also propose a dual gravity system based on a Scherk-Schwarz compactification of a D2 brane wrapped on a 3-torus and find a phase structure which is similar to the phase diagram found in the gauge theory calculation.