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Which chiral symmetry is restored in hot QCD?

Edward Shuryak
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Abstract

We review the current status of the problem of chiral symmetry restoration, discussing an open question of whether at the $SU(N_f)_A$ restoration point $T=T_c$ the $U(1)_A$ chiral symmetry is or is not (approximately) restored. New lattice and instanton-based studies are considered, and some new calculations are suggested to clarify the issue. We also speculate on possible experimental manifestations of two possible scenarios.

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Edward Shuryak. 1993-10-08. Which chiral symmetry is restored in hot QCD?. https://arxiv.org/abs/hep-ph/9310253

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