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arXiv · 1301.3796

On holographic thermalization and gravitational collapse of tachyonic scalar fields

Bin Wu
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Abstract

In this paper we study the thermalization of a spatially homogeneous system in a strongly coupled CFT. The non-equilibrium initial state is created by switching on a relevant perturbation in the CFT vacuum during Delta t >= t >= -Delta t. Via AdS/CFT, the thermalization process corresponds to the gravitational collapse of a tachyonic scalar field (m^2 = -3) in the Poincare patch of AdS_5. In the limit Delta t < 0.02/T, the thermalization time t_T is found to be quantitatively the same as that of a non-equilibrium state created by a marginal perturbation discussed in Ref. [5]. In the case Delta t >= 1/T, we also obtain double-collapse solutions but with a non-equilibrium intermediate state at t = 0. In all the cases our results show that the system thermalizes in a typical time t_T ~ O(1)/T. Besides, a conserved energy-moment current in the bulk is found, which helps understand the qualitative difference of the collapse process in the Poincare patch from that in global AdS[9, 10].

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Bin Wu. 2013-03-24. On holographic thermalization and gravitational collapse of tachyonic scalar fields. https://doi.org/10.1007/jhep04(2013)044

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