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arXiv · 0906.4423

Boost-invariant early time dynamics from AdS/CFT

Guillaume Beuf·Michal P. Heller·Romuald A. Janik·Robi Peschanski
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Abstract

Boost-invariant dynamics of a strongly-coupled conformal plasma is studied in the regime of early proper-time using the AdS/CFT correspondence. It is shown, in contrast with the late-time expansion, that a scaling solution does not exist. The boundary dynamics in this regime depends on initial conditions encoded in the bulk behavior of a Fefferman-Graham metric coefficient at initial proper-time. The relation between the early-time expansion of the energy density and initial conditions in the bulk of AdS is provided. As a general result it is proven that a singularity of some metric coefficient in Fefferman-Graham frame exists at all times. Requiring that this singularity at tau = 0 is a mere coordinate singularity without the curvature blow-up gives constraints on the possible boundary dynamics. Using a simple Pade resummation for solutions satisfying the regularity constraint, the features of a transition to local equilibrium, and thus to the hydrodynamical late-time regime, have been observed. The impact of this study on the problem of thermalization is discussed.

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Guillaume Beuf, Michal P. Heller, Romuald A. Janik, Robi Peschanski. 2009-10-16. Boost-invariant early time dynamics from AdS/CFT. https://doi.org/10.1088/1126-6708%2F2009%2F10%2F043

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