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Quenched divergences in the deconfined phase of SU(2) gauge theory

Joe Kiskis·Rajamani Narayanan
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Abstract

The spectrum of the overlap Dirac operator in the deconfined phase of quenched gauge theory is known to have three parts: exact zeros arising from topology, small nonzero eigenvalues that result in a non-zero chiral condensate, and the dense bulk of the spectrum, which is separated from the small eigenvalues by a gap. In this paper, we focus on the small nonzero eigenvalues in an SU(2) gauge field background at $β=2.4$ and $N_T=4$. This low-lying spectrum is computed on four different spatial lattices ($12^3$, $14^3$, $16^3$, and $18^3$). As the volume increases, the small eigenvalues become increasingly concentrated near zero in such a way as to strongly suggest that the infinite volume condensate diverges.

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Joe Kiskis, Rajamani Narayanan. 2001-09-07. Quenched divergences in the deconfined phase of SU(2) gauge theory. https://doi.org/10.1103/physrevd.64.117502

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