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arXiv · 2210.14385

Bump of sound velocity in dense 2-color QCD

Etsuko Itou·Kei Iida
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Abstract

We obtain the equation of state (EoS) and the sound velocity for 2-color QCD at low temperature and high density and find that in the superfluid phase, $c_s^2/c^2 >1/3$, where $1/3$ is the value at the relativistic limit. Several independent Monte Carlo studies on 2-color QCD have been conducted intensively in recent years. These works have shown a clear evidence of phase transition between hadronic and superfluid phases. In our paper[1], we have investigated the EoS and sound velocity in both phases. Our result is consistent with chiral perturbation theory in a low $\mu$ regime of the superfluid phase including the Bose-Einstein condensed phase, and shows a peak of sound velocity in the high-density BCS phase. We also give detailed simulation results and a comment on the holography bound in this proceedings.

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Etsuko Itou, Kei Iida. 2022-10-25. Bump of sound velocity in dense 2-color QCD. https://arxiv.org/abs/2210.14385

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