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Mean field exponents and small quark masses

Arne Hoell·Pieter Maris·Craig D. Roberts
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Abstract

We demonstrate that the restoration of chiral symmetry at finite-T in a class of confining Dyson-Schwinger equation (DSE) models of QCD is a mean field transition, and that an accurate determination of the critical exponents using the chiral and thermal susceptibilities requires very small values of the current-quark mass: log_{10}(m/m_u) < -5. Other classes of DSE models characterised by qualitatively different interactions also exhibit a mean field transition. Incipient in this observation is the suggestion that mean field exponents are a result of the gap equation's fermion substructure and not of the interaction.

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Arne Hoell, Pieter Maris, Craig D. Roberts. 1998-08-31. Mean field exponents and small quark masses. https://doi.org/10.1103/physrevc.59.1751

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