Wigner symmetry in the limit of large scattering lengths

TL;DR

This paper explores how Wigner's SU(4) symmetry emerges in nucleon-nucleon interactions when the scattering lengths become infinitely large, affecting effective field theory descriptions and certain scattering processes.

Contribution

It demonstrates that in the limit of infinite scattering lengths, the leading terms of the NN interaction are invariant under Wigner's SU(4) symmetry, providing new insights into nuclear force symmetries.

Findings

Wigner symmetry emerges at infinite scattering lengths.

Radiation pion effects vanish in this limit.

Implications for NN to NN axion and gamma d to n p processes.

Abstract

We note that in the limit where the NN 1S0 and 3S1 scattering lengths, a^(1S0) and a^(3S1), go to infinity, the leading terms in the effective field theory for strong NN interactions are invariant under Wigner's SU(4) spin-isospin symmetry. This explains why the leading effects of radiation pions on the S-wave NN scattering amplitudes vanish as a^(1S0) and a^(3S1) go to infinity. The implications of Wigner symmetry for NN to NN axion and gamma d to n p are also considered.