Salty popcorn in a homogeneous low-dimensional toy model of holographic QCD

TL;DR

This paper investigates a homogeneous ansatz in a low-dimensional toy model of holographic QCD to validate its use in describing finite baryon density configurations, revealing qualitative agreement with full solutions and identifying new layered transitions.

Contribution

It introduces a homogeneous ansatz in a simplified holographic QCD model, demonstrating its validity and uncovering new layered baryonic popcorn transitions at high density.

Findings

Homogeneous ansatz qualitatively matches full numerical solutions.

Identification of layered popcorn transitions in the model.

Exact solutions show transitions to multiple layers at high density.

Abstract

Recently, a homogeneous ansatz has been used to study cold dense nuclear matter in the Sakai-Sugimoto model of holographic QCD. To justify this homogeneous approximation we here investigate a homogeneous ansatz within a low-dimensional toy version of Sakai-Sugimoto to study finite baryon density configurations and compare it to full numerical solutions. We find the ansatz corresponds to enforcing a dyon salt arrangement in which the soliton solutions are split into half-soliton layers. Within this ansatz we find analogues of the proposed baryonic popcorn transitions, in which solutions split into multiple layers in the holographic direction. The homogeneous results are found to qualitatively match the full numerical solutions, lending confidence to the homogeneous approximations of the full Sakai-Sugimoto model. In addition, we find exact compact solutions in the high density, flat space limit which demonstrate the existence of further popcorn transitions to three layers and beyond.