Baryons and Chiral Symmetry

TL;DR

This paper discusses the significance of chiral symmetry in baryon physics, covering its role in nucleon structure, lattice calculations, and the chiral effective theory, highlighting recent theoretical insights.

Contribution

It provides a comprehensive overview of chiral symmetry's impact on baryon properties, including new perspectives on the Roper resonance and lattice results.

Findings

Chiral dynamics are crucial for understanding the Roper resonance.

Chiral symmetry influences lattice calculations of the $ ext{π}N$ sigma term and strangeness.

Chiral $U(1)$ anomaly affects the quark spin and orbital angular momentum evaluations.

Abstract

The relevance of chiral symmetry in baryons is highlighted in three examples in the nucleon spectroscopy and structure. The first one is the importance of chiral dynamics in understanding the Roper resonance. The second one is the role of chiral symmetry in the lattice calculation of $\pi N \sigma$ term and strangeness. The third one is the role of chiral $U(1)$ anomaly in the anomalous Ward identity in evaluating the quark spin and the quark orbital angular momentum. Finally, the chiral effective theory for baryons is discussed.