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arXiv · hep-ph/9702404

Instantons and the Chiral Phase Transition

Thomas Appelquist·Stephen B. Selipsky
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Abstract

We examine the role of instantons in the zero-temperature chiral phase transition in an SU(N) gauge theory. For a range of N_f (the number of fermion flavors) depending on N, the theory exhibits an infrared fixed point at coupling $α_*$. As N_f decreases, $α_*$ increases, and it eventually exceeds a critical value sufficient to trigger chiral symmetry breaking. For the case N = 2, we estimate the critical values of N_f and $α_*$ due to instantons by numerically solving a gap equation with an instanton-generated kernel. We find instanton effects of strength comparable to that of gluon exchange.

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Thomas Appelquist, Stephen B. Selipsky. 1997-02-23. Instantons and the Chiral Phase Transition. https://doi.org/10.1016/s0370-2693(97)00369-9

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