ABSTRACT
Certain experiments seem to have established the existence of a meson with a mass of about 725 MeV, along with the corresponding antiparticle. This chapter suggests that the isotopic doublet forms part of a unitary triplet in the eightfold way, along with a neutral isotopic singlet. Y. Nambu and J. J. Sakurai have discussed the possibility that κ(725) does not belong to a supermultiplet in the scheme; instead, its existence is supposed to be a manifestation of the mechanism that breaks the degeneracy of supermultiplets. The small width of κ(725) is then explained; its low production rates in many processes can be attributed, at least partially, to the absence or smallness of many pole terms. If one assumes the general correctness of the broken eightfold way scheme of approximate higher symmetry, it is interesting to speculate about the relation to the scheme of the new meson κ(725).
