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arXiv · hep-ph/9606459

Cool Pions move at less than the speed of light

Robert D. Pisarski·Michel Tytgat
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Abstract

At nonzero temperature, pions propagate through a thermal medium at less than the speed of light. About low temperature, this effect begins not at $\sim T^2$, but at next to leading order, $\sim T^4$. We also derive the generalization of the relation of Gell-Mann, Oakes, and Renner to nonzero temperature.

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Robert D. Pisarski, Michel Tytgat. 1996-06-27. Cool Pions move at less than the speed of light. https://arxiv.org/abs/hep-ph/9606459

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