Large N Gauge Theories from Orientifolds with NS-NS B-flux

TL;DR

This paper explores how turning on a quantized NS-NS B-field in non-compact orientifold setups modifies the resulting large N gauge theories, affecting brane configurations and supersymmetry, and demonstrates explicit constructions with various supersymmetries.

Contribution

It provides explicit construction of large N gauge theories from orientifolds with non-zero B-field backgrounds, revealing changes in brane configurations and supersymmetry properties.

Findings

Number of D7-branes reduced from 8 to 4 with B-field

Large N correlation functions match those of parent ${ m N}=4$ theory

Constructs theories with ${ m N}=2,1,0$ supersymmetry

Abstract

We consider D-branes and orientifold planes embedded in non-compact (orbifolded) space-time. We point out that even in the non-compact cases we can turn on non-zero (quantized) NS-NS antisymmetric B-field. In particular, we study the effect of the B-field on four dimensional large N gauge theories from orientifolds. Thus, in theories with both D3- and D7-branes, the effect of the B-field is non-trivial: the number of D7-branes (of each species) is reduced from 8 (which is the required number if the B-field is trivial) to 4. This results in a different orientifold string theory, and, subsequently, the corresponding large N gauge theory is also different. We explicitly construct large N gauge theories from orientifolds with non-zero B-field backgrounds with ${\cal N}=2,1,0$ supersymmetries. These theories, just as their counterparts without the B-field, have the property that in the large N limit computation of any M-point correlation function reduces to the corresponding computation in the parent ${\cal N}=4$ supersymmetric theory with a unitary gauge group.