HOLOGRAPHIC EQUILIBRATION IN CONFINING GAUGE THEORIES
Tuna Demircik
Physics, Doctor of Philosophy Thesis, 2017
Thesis Jury
Prof. Dr. Cihan Saçlıoğlu (Thesis Supervisor),
Assoc. Prof. Dr. Umut Gürsoy, Prof. Dr. Zafer Gedik,
Assoc. Prof. Dr. O. Teoman Turgut, Assoc. Prof. Dr. Kağan Kurşungöz
Date & Time: 9th, June 2017 – 14.00
Place: FENS G029
Keywords : AdS/CFT, Holographic QCD, Quasinormal modes, Equilibration
Abstract
We investigate the effect of external magnetic fields on equilibration in the improved holographic QCD theory in the deconfined phase using the gauge/gravity duality. In particular we calculate the quasinormal mode spectra in the corresponding black brane solutions and study their dependence on temperature, momentum and magnetic field, both in the scalar and the shear channels. We find complex patterns in the motion of quasinormal modes on the complex plane, including certain cross overs between the lowest lying modes under varying magnetic field, momentum and temperature. We also discover a critical value of the magnetic field Bc above which the hydrodynamic approximation breaks down, as the imaginary part of the first excited quasi-normal mode in the shear channel becomes smaller than that of the hydro mode. This thesis is mainly based on the published research [Nuclear Physics B 919 (2017) 384–403].