The Ideal Liquid Discovered by RHIC, Infrared Slavery Above and Hadronic Freedom Below $T_c$

TL;DR

This paper explores the nature of matter near and below the QCD critical temperature, revealing a transition from strongly bound mesons to a hadronic freedom regime with zero interactions, supported by RHIC data.

Contribution

It introduces a detailed description of the matter's evolution across the phase transition, combining infrared slavery and hidden local symmetry to explain meson properties and interactions.

Findings

Near $T_c$, mesons are extremely strongly bound with small size and zero energy.

Below $T_c$, mesons have zero mass and interactions vanish, indicating hadronic freedom.

Experimental evidence from STAR supports the zero-interaction regime below $T_c$.

Abstract

We construct the nature of the matter found in RHIC when its temperature has dropped down close to, and below, $T_c$. Just above $T_c$ it is composed of extremely strongly bound quark-antiquark pairs forming chirally restored mesons of the quantum numbers of the $\pi, S, \rho$ and $a_1$ with very small size and zero energy and just below $T_c$, it is composed of mesons of the same quantum numbers with zero mass. We invoke infrared slavery for the former and the vector manifestation (VM) of hidden local symmetry for the latter. As the temperature drops below $T_c$, the strongly bound quark-antiquark pairs are ejected into what is basically a region of "hadronic freedom" in which the interactions are zero. Experimental evidences for this are seen in the STAR data.