Stringy NJL and Gross-Neveu models at finite density and temperature

TL;DR

This paper investigates the phase structure of string-inspired nonlocal NJL and Gross-Neveu models at finite density and temperature using holographic duality, revealing both qualitative agreements and disagreements with local models.

Contribution

It introduces a holographic approach to analyze nonlocal stringy models at finite density and temperature, including off-shell Landau potential construction.

Findings

Qualitative agreement with local models in some phase features

Disagreement with local models in other phase aspects

Method for constructing off-shell Landau potentials

Abstract

Nonlocal stringy versions of the Nambu-Jona-Lasinio and Gross-Neveu models arise in a certain limit of holographic QCD. We analyze the phase structure at finite density and temperature at strong coupling in terms of probe branes in the gravity dual. Comparison with the phase structure of the local field theory models shows qualitative agreement with some aspects, and disagreement with others. Finally, we explain how to construct the Landau potentials for these models by taking the probe branes off-shell.