Instanton Bags, High Density Holographic QCD and Chiral Symmetry Restoration

TL;DR

This paper introduces an instanton bag model in holographic QCD, demonstrating how high-density baryonic states can restore chiral symmetry through non-diluted multi-instanton configurations.

Contribution

It presents the simplest example of an instanton bag in Euclidean space and connects it to high-density baryonic matter and chiral symmetry restoration in holographic QCD.

Findings

Instanton bag exhibits finite instanton density in three dimensions.

High-density baryonic states correspond to non-diluted multi-instanton solutions.

Chiral symmetry is restored in the instanton bag state.

Abstract

We describe the simplest example of an instanton bag in Euclidean space. It consists of a monopole wall and a Kaluza-Klein monopole wall, lifted to one higher dimension, trapping the instanton charge in the middle. This object has finite instanton density in a three-dimensional volume. Baryon physics in holographic QCD models gets translated into a multi-instanton problem in the bulk, and a state with a high density baryonic charge consists of a non-diluted multi-instanton solution. The instanton bag is a good candidate for this high-density state. We compute its parameters via moduli stabilization. Chiral symmetry restoration is exhibited by this state, and it is a direct consequence of its non-diluted features.