Testing S-duality with non-orientable surfaces

TL;DR

This paper tests S-duality in gauge theory by analyzing reductions on non-orientable surfaces, exploring branes, fluxes, and quantization of Hitchin moduli spaces, providing new insights into mirror symmetry and dualities.

Contribution

It introduces a novel approach to testing S-duality using non-orientable surface reductions and examines the associated branes, fluxes, and quantization in this context.

Findings

Verification of mirror symmetry on branes as predicted by S-duality.

Comparison of topological fluxes in 4D and 2D theories.

Quantization of Hitchin moduli space via non-orientable surfaces.

Abstract

Kapustin and Witten showed that a twisted version of N=4 gauge theory in four dimensions compactifies to a two-dimensional sigma-model whose target space is the Hitchin moduli space. In this talk, I consider the reduction of the gauge theory on a four dimensional orientable spacetime manifold which is not a global product of two surfaces but contains embedded non-orientable surfaces. The low energy theory is a sigma-model on a two dimensional worldsheet whose boundary components end on branes constructed from the Hitchin moduli space associated to a non-orientable surface. I will also compare the discrete topological fluxes in four and two dimensional theories and verify the mirror symmetry on branes as predicted by the S-duality in gauge theory. This provides another non-trivial test of $S$-duality using reduction along possibly non-orientable surfaces. Finally, I consider the quantisation of the Hitchin moduli space from a non-orientable surface as an example of quantisation via branes and mirror symmetry.