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Causal Diffusion and the Survival of Charge Fluctuations in Nuclear Collisions

Mohamed Abdel Aziz·Sean Gavin
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Abstract

Diffusion may obliterate fluctuation signals of the QCD phase transition in nuclear collisions at SPS and RHIC energies. We propose a hyperbolic diffusion equation to study the dissipation of net charge fluctuations. This equation is needed in a relativistic context, because the classic parabolic diffusion equation violates causality. We find that causality substantially limits the extent to which diffusion can dissipate these fluctuations.

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Mohamed Abdel Aziz, Sean Gavin. 2004-04-20. Causal Diffusion and the Survival of Charge Fluctuations in Nuclear Collisions. https://doi.org/10.1103/physrevc.70.034905

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