Brane Dynamics and Chiral non-Chiral Transitions

TL;DR

This paper explores brane configurations in supersymmetric gauge theories, revealing transitions between chiral and non-chiral models linked to instanton phenomena, and introduces specific brane setups with superpotentials.

Contribution

It introduces new brane configurations, including a 'cross' and 'fork' setup, to realize chiral matter and study chiral/non-chiral transitions in supersymmetric theories.

Findings

Identification of a superpotential in the 'cross' brane configuration.

Demonstration of chiral to non-chiral transitions related to instanton effects.

Analysis of orientifold projections affecting gauge group structures.

Abstract

We study brane realizations of chiral matter in N=1 supersymmetric gauge theories in four dimensions. A "cross" configuration which leads to "flavor doubling" is found to have a superpotential. The main example is realized using a special "fork" configuration. Many of the results are found by studying a SU times SU product gauge group first. The chiral theory is then an orientifold projection of the product gauge group. An interesting observation in the brane picture is that there are transitions between chiral and non chiral models. These transitions are closely related to small instanton transitions in six dimensions.