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arXiv · 1512.05347

Weak and strong coupling equilibration in nonabelian gauge theories

Liam Keegan·Aleksi Kurkela·Paul Romatschke·Wilke van der Schee·Yan Zhu
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Abstract

We present a direct comparison studying equilibration through kinetic theory at weak coupling and through holography at strong coupling in the same set-up. The set-up starts with a homogeneous thermal state, which then smoothly transitions through an out-of-equilibrium phase to an expanding system undergoing boost-invariant flow. This first apples-to-apples comparison of equilibration provides a benchmark for similar equilibration processes in heavy-ion collisions, where the equilibration mechanism is still under debate. We find that results at weak and strong coupling can be smoothly connected by simple, empirical power-laws for the viscosity, equilibration time and entropy production of the system.

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Liam Keegan, Aleksi Kurkela, Paul Romatschke, Wilke van der Schee, Yan Zhu. 2015-12-16. Weak and strong coupling equilibration in nonabelian gauge theories. https://doi.org/10.1007/jhep04(2016)031

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