Recent developments in SU(3) covariant baryon chiral perturbation theory

TL;DR

This paper reviews recent advances in covariant baryon chiral perturbation theory (BChPT), highlighting its development, challenges, and applications in understanding low-energy QCD phenomena involving strangeness.

Contribution

It provides a comprehensive overview of the latest progress in covariant BChPT, emphasizing the use of the EOMS scheme and its improved convergence and consistency.

Findings

Covariant BChPT with EOMS scheme satisfies all symmetry constraints.

Enhanced convergence compared to non-relativistic approaches.

Applications to three-flavor sector deepen understanding of strangeness in QCD.

Abstract

Baryon chiral perturbation theory (BChPT), as an effective field theory of low-energy quantum chromodynamics (QCD), has played and is still playing an important role in our understanding of non-perturbative strong interaction phenomena. In the past two decades, inspired by the rapid progress in lattice QCD simulations and the new experimental campaign to study the strangeness sector of low-energy QCD, many efforts have been made to develop a fully covariant BChPT and to test its validity in all scenarios. These new endeavours have not only deepened our understanding of some long-standing problems, such as the power-counting-breaking problem and the convergence problem, but also resulted in theoretical tools that can be confidently applied to make robust predictions. Particularly, the manifestly covariant BChPT supplemented with the extended-on-mass-shell (EOMS) renormalization scheme has been shown to satisfy all analyticity and symmetry constraints and converge relatively faster compared to its non-relativistic and infrared counterparts. In this article, we provide a brief review of the fully covariant BChPT and its latest applications in the $u$, $d$, and $s$ three-flavor sector.