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arXiv · 1807.10143

Lattice Boltzmann study of the one-dimensional boost-invariant expansion with anisotropic initial conditions

Victor E. Ambrus·Calin Guga-Rosian
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Abstract

A numerical algorithm for the implementation of anisotropic distributions in the frame of the relativistic Boltzmann equation is presented. The implementation relies on the expansion of the Romatschke-Strickland distribution with respect to orthogonal polynomials, which is evolved using the lattice Boltzmann algorithm. The validation of our proposed scheme is performed in the context of the one-dimensional boost invariant expansion (Bjorken flow) at various values of the ratio $η/ s$ of the shear viscosity to the entropy density. This study is limited to the case of massless particles obeying Maxwell-Jüttner statistics.

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Victor E. Ambrus, Calin Guga-Rosian. 2019-02-05. Lattice Boltzmann study of the one-dimensional boost-invariant expansion with anisotropic initial conditions. https://doi.org/10.1063/1.5090061

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