SU3noninvariance of the vacuum and the chiral-SU2× SU2-breaking parameter

Abstract

The effect of S${\mathrm{U}}_3$ noninvariance of the vacuum (i.e., $f_{\pi }\ne f_K\ne f_{\eta }$) on the chiral-S${\mathrm{U}}_2$ × S${\mathrm{U}}_2$-breaking parameter of Gell-Mann, Oakes, and Renner, and on the Gell-Mann-Okubo mass formula for the pseudoscalar meson octet is calculated in a nonlinear Lagrangian model of broken chiral S${\mathrm{U}}_3$ × S${\mathrm{U}}_3$ symmetry.