Collective description of low energy mesonic states

TL;DR

This paper presents a non-perturbative, collective approach to describing low-energy mesonic states in QCD using quasiparticles and the random phase approximation, effectively capturing meson phenomenology up to a few GeV.

Contribution

It introduces a novel non-perturbative scheme treating quarks as quasiparticles and describes mesons as collective quasiparticle-pair states, extending understanding of low-energy hadronic states.

Findings

Scheme successfully describes meson states up to a few GeV.

Quasiparticle approach captures essential features of low-energy mesons.

Random phase approximation provides a viable framework for this phenomenology.

Abstract

The phenomenology of hadronic states at high energy is well described in the framework of Quantum Chromodynamics. The theory, well established by now, cannot be applied to the description of quark-antiquark states at low energy unless their degrees of freedom are treated as effective ones, a condition resulting from confinement. Own to the similarities with other quantum many-body systems we have adopted a non-perturbative scheme where quarks are treated as quasiparticles, which further interact between them, allowing meson-like states to be described as collective superposition of quasiparticle-pairs. The results of the calculations, performed in the context of the random phase approximation method, show that this scheme is a suitable one to describe meson states up to energies of the order of couple of GeV.