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arXiv · 2103.15889

Causality violations in realistic simulations of heavy-ion collisions

Christopher Plumberg·Dekrayat Almaalol·Travis Dore·Jorge Noronha·Jacquelyn Noronha-Hostler
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Abstract

Causality is violated in the early stages of state-of-the-art heavy-ion hydrodynamic simulations. Such violations are present in up to 75% of the fluid cells in the initial time and only after 2-3 fm/$c$ of evolution do we find that 50% of the fluid cells are definitely causal. Superluminal propagation reaches up to 15% the speed of light in some of the fluid cells. The inclusion of pre-equilibrium evolution significantly reduces the number of acausal cells. Our findings suggests that relativistic causality may place constraints on the available parameter space of heavy-ion collision simulations when factored into more thorough statistical analyses.

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Christopher Plumberg, Dekrayat Almaalol, Travis Dore, Jorge Noronha, Jacquelyn Noronha-Hostler. 2021-03-29. Causality violations in realistic simulations of heavy-ion collisions. https://doi.org/10.1103/physrevc.105.l061901

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