Universal Short-Range Repulsion in the Baryon System Originating from the Confinement --Approach in String-Junction Model--

TL;DR

This paper proposes a unified understanding of short-range repulsion in baryon interactions and neutron star matter using the string-junction model, linking confinement effects to repulsive forces.

Contribution

It introduces a confinement-based approach in the string-junction model to explain universal short-range repulsion in baryon systems, supported by lattice QCD insights.

Findings

Numerical results support the confinement-origin of repulsion.

The model explains the repulsive core in baryon-baryon interactions.

Implications for neutron star equation of state are discussed.

Abstract

We show a way to unifiedly understand the origins of the repulsive core of baryon-baryon interaction and the universal repulsion of three-baryon interaction needed to avoid dramatic softening of the equation of state of neutron stars due to hyperon mixing. For this aim we adopt the string-junction model which embodies the essential aspects of the confinement in the baryon system confirmed by recent lattice QCD calculations. Key concept of this study lies in the recognition that baryonic short-range repulsion appears as the latent effect implying the energy necessary for full overlap of baryons, for the confinement to persist at such situation. Numerical results are shown and related problems are discussed.