Mesonic quasinormal modes of the Sakai-Sugimoto model at high temperature

TL;DR

This paper investigates the thermal mesonic spectrum in the high-temperature phase of the Sakai-Sugimoto holographic QCD model by calculating quasinormal modes of scalar and vector mesons using numerical methods.

Contribution

It introduces a coordinate transformation that simplifies the calculation of quasinormal modes and analyzes the impact of finite momentum on the spectra.

Findings

Identified quasinormal frequencies for scalar and vector mesons at high temperature.

Demonstrated the effectiveness of a new coordinate change for numerical analysis.

Showed how finite momentum affects mesonic quasinormal modes.

Abstract

We examine the mesonic thermal spectrum of the Sakai-Sugimoto model of holographic QCD by finding the quasinormal frequencies of the supergravity dual. If flavour is added using D8 and anti-D8 branes there exist embeddings where the D-brane worldvolume contains a black hole. For these embeddings (the high-temperature phase of the Sakai-Sugimoto model) we determine the quasinormal spectra of scalar and vector mesons arising from the worldvolume DBI action of the D-brane. We stress the importance of a coordinate change that makes the in-falling quasinormal modes regular at the horizon allowing a simple numerical shooting technique. Finally we examine the effect of finite spatial momentum on quasinormal spectra.