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arXiv · hep-ph/9609414

On the Physics of a Cool Pion Gas

Robert D. Pisarski·Michel Tytgat
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Abstract

At finite temperature, the Nambu-Goldstone bosons of a spontaneously broken chiral symmetry travel at a velocity $v < 1$. This effect first appears at order $\sim T^4$ in an expansion about low temperature, and can be related to the appearence of two distinct pion decay constants in a thermal bath. We discuss some consequences on the thermodynamics of a gas of massless pions.

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Robert D. Pisarski, Michel Tytgat. 1996-09-19. On the Physics of a Cool Pion Gas. https://arxiv.org/abs/hep-ph/9609414

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