Hall Droplet Sheets in Holographic QCD

TL;DR

This paper presents a string theory holographic model of baryonic sheets in single-flavor QCD, describing their structure, properties, and associated vortex strings, with explicit calculations of tension, thickness, and effective actions.

Contribution

It introduces a novel holographic description of baryonic sheets as D-brane configurations in the Witten-Sakai-Sugimoto model, including detailed physical properties and boundary structures.

Findings

Computed the tension and thickness of the sheets and vortex strings.

Provided a four-dimensional effective action for the sheets and vortex strings.

Described the structure of baryonic sheets with a gluonic core and mesonic shell.

Abstract

In single-flavor QCD, the low energy description of baryons as Skyrmions is not available. In this case, it has been proposed by Komargodski that baryons can be viewed as kinds of charged quantum Hall droplets, or "sheets". In this paper we propose a string theory description of the sheets in single-flavor holographic QCD, focusing on the Witten-Sakai-Sugimoto model. The sheets have a "hard" gluonic core, described by D6-branes, and a "soft" mesonic shell, dual to non-trivial D8-brane gauge field configurations. We first provide the description of an infinitely extended sheet with massless or moderately massive quarks. Then, we construct a semi-infinite sheet ending on a one-dimensional boundary, a "vortex string". The holographic description allows for the precise calculation of sheet observables. In particular, we compute the tension and thickness of the sheet and the vortex string, and provide their four dimensional effective actions.