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arXiv · 1712.03248

Anomalous dynamics triggered by a non-convex equation of state in relativistic flows

J. M. Ibáñez·A. Marquina·S. Serna·M. A. Aloy
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Abstract

The non-monotonicity of the local speed of sound in dense matter at baryon number densities much higher than the nuclear saturation density ($n_0 \approx 0.16\,$fm$^{-3}$) suggests the possible existence of a non-convex thermodynamics which will lead to a non-convex dynamics. Here, we explore the rich and complex dynamics that an equation of state (EoS) with non-convex regions in the pressure-density plane may develop as a result of genuinely relativistic effects, without a classical counterpart. To this end, we have introduced a phenomenological EoS, whose parameters can be restricted heeding to causality and thermodynamic stability constraints. This EoS shall be regarded as a toy-model with which we may mimic realistic (and far more complex) EoS of practical use in the realm of Relativistic Hydrodynamics.

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J. M. Ibáñez, A. Marquina, S. Serna, M. A. Aloy. 2018-01-07. Anomalous dynamics triggered by a non-convex equation of state in relativistic flows. https://doi.org/10.1093/mnras%2Fsty137

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