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

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 ${\eta }^{\prime }$ 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.

Comments: Invited lecture to appear in the proceedings of the 3rd International Conference on New Frontiers in Physics, Kolymbari, Crete, 2014. 20 pages, 5 figures, 3 tables; v2: minor corrections, references added