Complex Saddles in Two-dimensional Gauge Theory
High Energy Physics - Theory
2016-04-13 v2 High Energy Physics - Lattice
Abstract
We study numerically the saddle point structure of two-dimensional (2D) lattice gauge theory, represented by the Gross-Witten-Wadia unitary matrix model. The saddle points are in general complex-valued, even though the original integration variables and action are real. We confirm the trans-series/instanton gas structure in the weak-coupling phase, and identify a new complex-saddle interpretation of non-perturbative effects in the strong-coupling phase. In both phases, eigenvalue tunneling refers to eigenvalues moving off the real interval, into the complex plane, and the weak-to-strong coupling phase transition is driven by saddle condensation.
Cite
@article{arxiv.1512.09021,
title = {Complex Saddles in Two-dimensional Gauge Theory},
author = {P. V. Buividovich and Gerald V. Dunne and S. N. Valgushev},
journal= {arXiv preprint arXiv:1512.09021},
year = {2016}
}
Comments
4+4 pages RevTeX, 9 figures; v2: version published in PRL