Abstract
We investigate the behavior under of the hadron energy density and the closely related question of how the divergences of the axial-vector currents and the strangeness-changing vector currents transform under . We assume that two terms in the energy density break symmetry; under one transforms as a singlet, the other as the member of an octet. The simplest possible behavior of these terms under chiral transformations is proposed: They are assigned to a single (3,)+(,3) representation of and parity together with the current divergences. The commutators of charges and current divergences are derived in terms of a single constant that describes the strength of the -breaking term relative to the chiral symmetry-breaking term. The constant is found not to be small, as suggested earlier, but instead close to the value () corresponding to an symmetry, realized mainly by massless pions rather than parity doubling. Some applications of the proposed commutation relations are given, mainly to the pseudoscalar mesons, and other applications are indicated.
- Received 22 July 1968
DOI:https://doi.org/10.1103/PhysRev.175.2195
©1968 American Physical Society