The role of monopoles in a Gluon Plasma

TL;DR

This paper investigates magnetic monopoles in a high-temperature gluon plasma, revealing their significant impact on transport properties despite their rarity, which influences the plasma's viscosity and hydrodynamic behavior.

Contribution

It provides the first detailed analysis of gluon-monopole scattering and demonstrates monopoles' crucial role in QGP transport properties at high temperatures.

Findings

Monopoles have a large transport cross section, surpassing pQCD gluon-gluon scattering.

Monopoles significantly influence QGP viscosity and hydrodynamic applicability.

Gluon-monopole scattering was solved for the first time.

Abstract

We study the role of magnetic monopoles at high enough temperature $T>2T_c$, when they can be considered heavy, rare objects embedded into matter consisting mostly of the usual "electric" quasiparticles, quarks and gluons. We review available lattice results on monopoles at finite temperatures. Then we proceed to classical and quantum charge-monopole scattering, solving the problem of gluon-monopole scattering for the first time. We find that, while this process hardly influences thermodynamic quantities, it does produce a large transport cross section, significantly exceeding that for pQCD gluon-gluon scattering up to quite high $T$. Thus, in spite of their relatively small density at high $T$, monopoles are extremely important for QGP transport properties, keeping viscosity small enough for hydrodynamics to work at LHC.