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arXiv · 1505.05012

Universal relaxation in quark-gluon plasma at strong coupling

Alex Buchel·Andrew Day
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Abstract

We use top-down gauge theory/string theory correspondence to compute relaxation rates in strongly coupled nonconformal gauge theory plasma. We compare models with difference mechanisms of breaking the scale invariance: "hard breaking" (by relevant operators) and "soft breaking" (by marginal operators). We find that the thermalization time of the transverse traceless fluctuations of the stress-energy tensor is rather insensitive to the mechanisms of breaking the scale invariance over a large range of the scale-breaking parameter $\delta=\frac 13-c_s^2$. We comment on the relevance of the results to QCD quark-gluon plasma.

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Alex Buchel, Andrew Day. 2015-05-19. Universal relaxation in quark-gluon plasma at strong coupling. https://doi.org/10.1103/physrevd.92.026009

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