Quenched Gauge Theory Research Articles

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

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 $\beta=2.4$ 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.

Chiral condensate in the deconfined phase of quenched gauge theories

We compute the low lying spectrum of the overlap Dirac operator in the deconfined phase of finite-temperature quenched gauge theory. It suggests the existence of a chiral condensate which we confirm with a direct stochastic estimate. We show that the part of the spectrum responsible for the chiral condensate can be understood as arising from a dilute gas of instantons and anti-instantons.

A lattice determination of the slope at q2 = 0 of the topological susceptibility in SU (3) Yang-Mills theory

We determine the slope of the topological susceptibility at q 2 = 0 by Monte Carlo simulations, for an SU(3) quenched gauge theory. The value is consistent with the phenomenological estimates, within the (large) errors.

A lattice determination of the slope of the topological susceptibility at q2=0

The slope of the topological susceptibility at q 2=0 is determined by Monte Carlo simulation for an SU(2) quenched gauge theory. Both the sign and the magnitude agree with the sum rule phenomenological determinations.

Universality and scaling in quenched SU(2) hadronic mass spectrum

We analyze the hadronic mass spectrum of an SU(2) quenched gauge theory in the ( β, β A) plane. We find that, for small β, A < 0, universality holds for ∝ ψ∝ and m ϱ ∝, m πand m ϱ. The ∝ ψ∝ and m ϱ behaviour is consistent with scaling; ƒπ is not constant in physical units.