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arXiv · 2105.04535

Insights on the peak in the speed of sound of ultradense matter

Maurício Hippert·Eduardo S. Fraga·Jorge Noronha
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Abstract

In this work we investigate the minimal physical requirements needed for generating a speed of sound that surpasses its asymptotic conformal limit. It is shown that a peak in the speed of sound of homogeneous matter naturally emerges in the transition from a phase with broken chiral symmetry to one with a gapped Fermi surface. We argue that this could be relevant for understanding the peak in the speed of sound displayed by some of the current models for cold ultradense matter. A minimal model implementation of this mechanism is presented, based on the spontaneous breakdown of an approximate particle-antiparticle symmetry, and its thermodynamic properties are determined.

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Maurício Hippert, Eduardo S. Fraga, Jorge Noronha. 2021-05-10. Insights on the peak in the speed of sound of ultradense matter. https://doi.org/10.1103/physrevd.104.034011

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