Chiral Symmetry and Axial Anomaly in Hadron and Nuclear Physics --- a review --

TL;DR

This review discusses the significance of chiral symmetry and axial anomaly in QCD, exploring their roles in nuclear physics, chiral restoration in hot/dense matter, and effective anomaly restoration indicated by eta prime meson behavior.

Contribution

It provides a comprehensive overview of recent developments in understanding chiral symmetry and axial anomaly effects in hot and dense nuclear matter.

Findings

Chiral symmetry plays a crucial role in QCD and nuclear physics.

Evidence suggests possible chiral restoration in hot/dense environments.

Changes in eta prime meson properties indicate effective restoration of axial anomaly.

Abstract

The important role played by chiral symmetry and axial anomaly in QCD in nuclear physics is reviewed. Some recent topics on possible chiral restoration in hot and/or dense matter are picked up. We also discuss so called {\em effective} restoration of chiral anomaly hot and/or dense matter, as may be seen in a character change of $\eta '$ meson.