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arXiv · 1811.04040

Quasinormal modes of magnetic black branes at finite 't Hooft coupling

Sebastian Waeber
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Abstract

The aim of this work is to extend the knowledge about Quasinormal Modes (QNMs) and the equilibration of strongly coupled systems, specifically of a quark gluon plasma (which we consider to be in a strong magnetic background field) by using the duality between $\mathcal{N}=4$ Super Yang-Mills (SYM) theory and type IIb Super Gravity (SUGRA) and including higher derivative corrections. The behaviour of the equilibrating system can be seen as the response of the system to tiny excitations. A quark gluon plasma in a strong magnetic background field, as produced for very short times during an actual heavy ion collision, is described holographically by certain metric solutions to $5\text{D}$ Einstein-Maxwell-(Chern-Simons) theory, which can be obtained from type IIb SUGRA. We are going to compute higher derivative corrections to this metric and consider $\alpha'^3$ corrections to tensor-quasinormal modes in this background geometry. We find indications for a strong influence of the magnetic background field on the equilibration behaviour also and especially when we include higher derivative corrections.

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Sebastian Waeber. 2018-11-09. Quasinormal modes of magnetic black branes at finite 't Hooft coupling. https://doi.org/10.1007/jhep08(2019)006

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