Wilson Loop in Classical Lattice Gauge Theory and the Thermal Width of Heavy Quarkonium

TL;DR

This paper estimates the imaginary part of the finite temperature static potential using classical lattice gauge theory, linking it to heavy quarkonium spectral functions and comparing classical and HTL simulation results.

Contribution

It introduces a method to extract the imaginary part of the static potential from Wilson loop evolution and compares classical and HTL simulation outcomes.

Findings

Classical lattice gauge theory can estimate the static potential's imaginary part.

Results are consistent with resummed perturbation theory.

Comparison shows agreement between classical and HTL simulations.

Abstract

We present an estimate for the imaginary part of the recently introduced finite temperature real-time static potential. It can be extracted from the time evolution of the Wilson loop in classical lattice gauge theory. The real-time static potential determines, through a Schroedinger-type equation and a subsequent Fourier-transform of its solution, the spectral function of heavy quarkonium in finite-temperature QCD. We also compare the results of the classical simulations with those of Hard Thermal Loop improved simulations, as well as with analytic expectations based on resummed perturbation theory.