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arXiv · 1006.0387

Investigation of shock waves in the relativistic Riemann problem: A comparison of viscous fluid dynamics to kinetic theory

I. Bouras·E. Molnar·H. Niemi·Z. Xu·A. El·O. Fochler·C. Greiner·D. H. Rischke
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Abstract

We solve the relativistic Riemann problem in viscous matter using the relativistic Boltzmann equation and the relativistic causal dissipative fluid-dynamical approach of Israel and Stewart. Comparisons between these two approaches clarify and point out the regime of validity of second-order fluid dynamics in relativistic shock phenomena. The transition from ideal to viscous shocks is demonstrated by varying the shear viscosity to entropy density ratio $\eta/s$. We also find that a good agreement between these two approaches requires a Knudsen number $Kn < 1/2$.

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I. Bouras, E. Molnar, H. Niemi, Z. Xu, A. El, O. Fochler, C. Greiner, D. H. Rischke. 2010-06-02. Investigation of shock waves in the relativistic Riemann problem: A comparison of viscous fluid dynamics to kinetic theory. https://doi.org/10.1103/physrevc.82.024910

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