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arXiv · 1610.08987

Holographic Isotropisation in Gauss-Bonnet Gravity

Tomas Andrade·Jorge Casalderrey-Solana·Andrej Ficnar
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Abstract

We study holographic isotropisation of homogeneous, strongly coupled, non-Abelian plasmas in Gauss-Bonnet gravity with a negative cosmological constant. We focus on small values of the Gauss-Bonnet coupling parameter $λ_{GB}$ and linearise the equations of motion around a time-dependent background solution with $λ_{GB}=0$. We numerically solve the linearised equations and show that the entire time evolution of the pressure anisotropy can be well approximated by the linear in $λ_{GB}$ corrections to the quasinormal mode expansion, even in the cases of high anisotropy. We finally show that, quite generally, the time evolution of the pressure anisotropy with the Gauss-Bonnet term is approximately {\it shifted} with respect to the evolution without it, with the sign of the shift being directly related to the sign of the $λ_{GB}$ parameter. This suggests that finite coupling corrections generically {\it increase} the isotropisation time of strongly coupled plasmas.

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Tomas Andrade, Jorge Casalderrey-Solana, Andrej Ficnar. 2016-11-30. Holographic Isotropisation in Gauss-Bonnet Gravity. https://doi.org/10.1007/jhep02(2017)016

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