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arXiv · hep-ph/0301275

Superluminal pions in a hadronic fluid

Neven Bilic·Hrvoje Nikolic
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Abstract

We study the propagation of pions at finite temperature and finite chemical potential in the framework of the linear sigma model with 2 quark flavors and $N_c$ colors. The velocity of massless pions in general differs from that of light. One-loop calculations show that in the chiral symmetry broken phase pions, under certain conditions, propagate faster than light.

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Neven Bilic, Hrvoje Nikolic. 2003-08-26. Superluminal pions in a hadronic fluid. https://doi.org/10.1103/physrevd.68.085008

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