On Dp-Dp+4 systems, QCD dual and phenomenology

TL;DR

This paper explores holographic duals of large N QCD using D-brane systems, investigates supersymmetry breaking mechanisms, and discusses challenges in embedding the Standard Model within this framework.

Contribution

It proposes a candidate D-brane system for a holographic dual of large N QCD and analyzes supersymmetry breaking via D7-anti-D7 condensation.

Findings

A candidate holographic dual system is identified but lacks explicit solutions.

Supersymmetry breaking is achieved through D7-anti-D7 condensation to D5.

Challenges in embedding the Standard Model with appropriate low-energy fields are discussed.

Abstract

D4-D8 and D3-D7 systems are studied and a possible holographic dual of large N QCD (SU(N) gauge fields and fundamental quarks) is sought. A candidate system is found, for which however no explicit solution is available. Susy is broken by having a $D7-\bar{D7}$ condensing to a D5. The mechanism for supersymmetry breaking is then used to try to construct a Standard Model embedding. One can either obtain too few low energy fields or too many. The construction requires TeV scale string theory.