Fluctuations of conserved charges, chiral spin symmetry and deconfinement in an SU(2)_color subgroup of SU(3)_color above T_c

TL;DR

This paper investigates the behavior of conserved charge fluctuations, chiral spin symmetry, and deconfinement phenomena in an SU(2) subgroup of SU(3) color above the critical temperature, revealing complex quark interactions.

Contribution

It demonstrates the emergence of chiral spin symmetry and the absence of interquark interactions in certain channels, reconciling empirical observations with a deconfined SU(2) subgroup.

Findings

Fluctuations behave as free particles above T_c

Chiral spin symmetry emerges between T_c and 3T_c

Evidence of deconfinement in SU(2) subgroup

Abstract

Above a pseudocritical temperature of chiral symmetry restoration T_c the energy and the pressure are very far from the quark-gluon-plasma limit (i.e. ideal gas of free quarks and gluons). At the same time very soon above T_c fluctuations of conserved charges behave as if quarks were free particles. Within the T_c - 3T_c interval a chiral spin symmetry emerges in QCD which is not consistent with free quarks and suggests that degrees of freedom are chirally symmetric quarks bound into the color-singlet objects by the chromoelectric field. Here we analyse temporal and spatial correlators in this interval and demonstrate that they indicate simultaneously the chiral spin symmetry as well as absence of the interquark interactions in channels constrained by a current conservation. The latter channels are responsible for both fluctuations of conserved charges and for dileptons. Assuming that a SU(2)_color subgroup of SU(3)_color is deconfined soon above T_c but confinement persits in SU(3)_color/SU(2)_color in the interval T_c - 3T_c we are able to reconcile all empirical facts listed above.