D7 brane embeddings and chiral symmetry breaking

Abstract

We study the embedding of D7 brane probes in five geometries that are deformations of AdS5 × S5. Each case corresponds to the inclusion of quark fields in a dual gauge theory where we are interested in investigating whether chiral symmetry breaking occurs. We use a supersymmetric geometry describing an N = 2 theory on its moduli space and a dilaton driven non-supersymmetric flow to establish criteria for a chiral symmetry breaking embedding. We develop a simple spherical D7 embedding that tests the repulsion of the core of the geometry and signals dynamical symmetry breaking. We then use this tool in more complicated geometries to show that an N = 2* theory and a non-supersymmetric theory with scalar masses do not induce a chiral condensate. Finally we provide evidence that the Yang Mills* geometry does. © SISSA/ISAS 2005.