Strings on pp-waves and Hadrons in (softly broken) N=1 gauge theories

TL;DR

This paper explores the string spectrum and hadron properties in softly broken N=1 gauge theories via Penrose limits of Type IIB dual backgrounds, revealing non-perturbative effects and thermodynamic characteristics.

Contribution

It provides the first detailed analysis of string spectra on pp-wave backgrounds derived from deformed supergravity duals of N=1 gauge theories, highlighting non-perturbative corrections.

Findings

String zero-point energy is nontrivial and negative, affecting hadron mass spectrum.

Non-perturbative corrections are present due to loss of worldsheet supersymmetry.

Calculated Hagedorn temperatures indicate thermodynamic limits of the models.

Abstract

We study the Penrose limit of Type IIB duals of softly broken N=1 SU(N) gauge theories in four dimensions, obtained as deformations of the Maldacena-Nunez and Klebanov-Strassler backgrounds. We extract the string spectrum on the resulting pp-wave backgrounds and discuss some properties of the conjectured dual gauge theory hadrons, the so called "Annulons". The string zero-point energy on the light-cone is nontrivial, due to the loss of linearly realized worldsheet supersymmetry, and negative, even in the unbroken supersymmetric case. This causes the appearance of non-perturbative corrections to the hadronic mass spectrum. We briefly discuss the thermodynamic behavior of these string models, calculating the corresponding Hagedorn temperatures.