The Witten-Sakai-Sugimoto model: A brief review and some recent results

TL;DR

This paper reviews the Witten-Sakai-Sugimoto holographic model of low-energy QCD, discussing its predictions for meson spectra, glueballs, and the QCD phase diagram, with recent results relevant to future experimental research.

Contribution

It provides a concise overview of the model's predictions and presents new results on glueball spectra and QCD phase diagram under various conditions.

Findings

Predicted meson spectra and gluon condensate align with experimental data.

Calculated glueball decay rates into pions.

Mapped the QCD phase diagram at finite temperature, density, and magnetic field.

Abstract

A brief review of the Witten-Sakai-Sugimoto model is given, which is a top-down holographic model of low-energy QCD with chiral quarks derived from type-IIA superstring theory. The main predictions of the model, in particular concerning meson spectra, the gluon condensate, the QCD string tension, the mass of the $\eta'$ and of baryons are discussed and compared quantitatively with available experimental and/or lattice results. Then some recent results of potential interest to the physics program at the future FAIR facility are presented: The spectrum of glueballs and their decay rates into pions, and the phase diagram of QCD at finite temperature, density, and magnetic field strength.