Chiral symmetry in the high-temperature plasma phase of QCD is consistent with at least three qualitatively different quark dispersion relations. The rate for qq → e+e-, with zero total momentum of the e+e- pair in the plasma rest frame is direct measure of the quark dispersion relation. For the three plausible dispersion relations the rates differ by orders of magnitude when the e+e- invariant mass M < 2T.
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I am grateful to S. Rudaz and O. Vails for fruitful discussions. This work was supported by a Summer Research Grant from the Graduate School of the University of Minnesota.