Low-energy theorems and spectral density of the Dirac operator in AdS/QCD

TL;DR

This paper investigates how AdS/QCD models replicate low-energy theorems of QCD, focusing on spectral density of the Dirac operator, and shows their compatibility in the chiral limit through holographic duality.

Contribution

It demonstrates that AdS/QCD models are consistent with QCD low-energy theorems in the chiral limit by analyzing spectral density and partition functions.

Findings

AdS/QCD models reproduce the analytical behavior of low-energy theorems.

Spectral density is expressed via a partition function of a QCD-like theory.

Models are compatible with the theorems as quark mass approaches zero.

Abstract

We study the low-energy theorems of QCD from the point of view of the dual AdS/QCD models and demonstrate that these models are compatible with the theorems in the chiral limit, i.e. the arising expressions have the same analytical behavior at the pole when the quark mass tends to zero. Low-energy theorems are formulated in terms of the spectral density of the Dirac operator. In order to calculate the spectral density in the dual holographic models we express it in terms of a partition function of a QCD-like theory.