Orientifolds, M-Theory, and the ABCD's of the Enhancon

TL;DR

This paper explores the emergence of enhancons in various gauge theories using orientifolds, connecting supergravity solutions, M-theory, and monopole moduli spaces, and classifies different types of enhancons based on gauge group symmetries.

Contribution

It extends the concept of enhancons to SO and USp gauge theories, classifies their types, and relates them to M-theory and monopole moduli spaces, providing new insights into their structure and corrections.

Findings

Enhancons appear in SO(2N+1), USp(2N), and SO(2N) gauge theories.

Different enhancon types (A, B, C, D) are distinguished by global and local properties.

Connection established between enhancons, M-theory, and monopole moduli spaces.

Abstract

Supergravity solutions related to large N SU(N) pure gauge theories with eight supercharges have recently been shown to give rise to an ``enhancon'', a new type of hypersurface made of D-branes. We show that enhancons also arise in similar situations pertaining to SO(2N+1), USp(2N) and SO(2N) gauge theories, using orientifolds. Enhancons therefore appear to come in types A, B, C, and D. The latter three differ globally from type A by having an extra Z_2 identification, and are distinguished locally by their subleading behaviour in large N. We focus mainly on 2+1 dimensional gauge theory, where a relation to M-theory and the Atiyah-Hitchin and Taub-NUT manifolds enables the construction of the smooth supergravity solution and the study of some of the 1/N corrections. The role of the enhancon in eleven dimensional supergravity is also uncovered. There is a close relation to certain multi-monopole moduli space problems.