Glueballs and the Yang-Mills plasma in a $T$-matrix approach

TL;DR

This paper investigates the existence of glueballs in the Yang-Mills plasma using a non-perturbative $T$-matrix approach, showing they remain bound up to 1.3 times the critical temperature and computing the equation of state consistent with lattice data.

Contribution

It introduces a $T$-matrix formalism to analyze glueball bound states and plasma properties in Yang-Mills theories, including large-$N$ and $G_2$ gauge groups, based on lattice-QCD potentials.

Findings

Glueballs are bound up to 1.3 T_c.

The plasma equation of state matches lattice data.

Analytical results for large-$N$ gauge groups.

Abstract

The strongly coupled phase of Yang-Mills plasma with arbitrary gauge group is studied in a $T$-matrix approach. The existence of lowest-lying glueballs, interpreted as bound states of two transverse gluons (quasi-particles in a many-body set up), is analyzed in a non-perturbative scattering formalism with the input of lattice-QCD static potentials. Glueballs are actually found to be bound up to 1.3 $T_c$. Starting from the $T$-matrix, the plasma equation of state is computed by resorting to Dashen, Ma and Bernstein's formulation of statistical mechanics and favorably compared to quenched lattice data. Special emphasis is put on SU($N$) gauge groups, for which analytical results can be obtained in the large-$N$ limit, and predictions for a $G_2$ gauge group are also given within this work.