Elliptic Flow, Kasner Universe and Holographic Dual of RHIC Fireball

TL;DR

This paper develops a holographic model for anisotropic elliptic flow in strongly coupled plasma, linking Kasner spacetime geometry to hydrodynamics and initial conditions, extending previous isotropic models.

Contribution

It introduces a holographic dual of anisotropic plasma expansion incorporating Kasner spacetime, extending Bjorken's model to three dimensions with anisotropy.

Findings

Kasner spacetime constrains the dual geometry and hydrodynamics.

Elliptic flow parameters are expressed in terms of anisotropy parameters.

Hydrodynamic quantities depend on initial conditions and fundamental constants.

Abstract

We consider a holographic dual of hydrodynamics of N=4 SYM plasma that undergoes non-isotropic three-dimensional expansion relevant to RHIC fireball. Our model is a natural extension of the Bjorken's one-dimensional expansion, and it describes an elliptic flow whose v2 and eccentricity are given in terms of anisotropy parameters. Holographic renormalization shows that absence of conformal anomaly in the SYM theory constrains our local rest frame to be a Kasner spacetime. We show that the Kasner spcetime provides a simple description of the anisotropically expanding fluid within a well-controled approximation. We also find that the dual geometry determines some of the hydrodynamic quantities in terms of the initial condition and the fundamental constants.