Is holographic quark-gluon plasma homogeneous?

TL;DR

This paper provides evidence from holographic models that the quark-gluon plasma may exhibit spatial inhomogeneities due to a universal instability driven by the Chern-Simons term, especially at low densities.

Contribution

It demonstrates a universal spatially modulated instability in holographic models of quark-gluon plasma, linked to flavor anomalies, and suggests inhomogeneous phases could exist in the crossover region.

Findings

Evidence of spatially modulated instability in holographic models.

Instability driven by Chern-Simons term related to flavor anomalies.

Occurs at low densities within the crossover region.

Abstract

We present evidence for a spatially modulated instability within the deconfined quark-gluon plasma phase of QCD. This evidence is based on robust predictions from generic holographic models, accurately fitted to lattice data, where the instability is driven by the Chern-Simons term mandated by the flavor anomalies of QCD. Such an instability occurs universally across holographic models at surprisingly low densities, within the crossover region amenable to lattice and experimental studies, therefore inviting further explorations of inhomogeneous phases in this region.