Holographic phase transition of QCD with back-reaction of flavors

TL;DR

This paper investigates the confinement/deconfinement transition in holographic QCD by incorporating the back-reaction of a scalar field related to chiral symmetry breaking, analyzing how quark mass and flavor number affect the critical temperature.

Contribution

It introduces a deformed AdS black hole solution accounting for back-reaction of the scalar field, providing a more realistic holographic model of QCD phase transitions.

Findings

Critical temperature depends on quark mass and flavor number.

Unphysical phases from previous models are eliminated with back-reaction.

Results align with lattice QCD observations.

Abstract

We revisit confinement/deconfinement transition in holographic QCD to consider the back-reaction of a bulk scalar field. The bulk scalar field is dual to a quark bi-linear operator $\bar qq$, and it encodes explicit and spontaneous chiral symmetry breaking of QCD. To perform the Hawking-Page transition analysis with the back-reaction, we first obtain a deformed AdS black hole solution due to a finite quark mass. Through the Hawking-Page analysis with the back-reacted geometry, we study the flavor number $N_f$ and finite quark mass dependence of the critical temperature of the QCD confinement/deconfinement transition. In addition, we confirm that unphysical QCD phase haunting around in a previous study disappears with the back-reaction. We discuss our results in the light of lattice QCD observations.