Gauge models with right-handed currents, neutrino interactions, andKL−KSmass difference

We discuss weak interaction models with new right-handed charm-changing currents and $\Delta I=\frac{1}{2}$ rule within the SU(2) X U(1) X G and ${\mathrm{SU}\mathrm{}\left(2\right)\mathrm{}}_A\times {\mathrm{SU}\mathrm{}\left(2\right)\mathrm{}}_B\times {\mathrm{SU}\mathrm{}\left(4\right)\mathrm{}}^{\prime }$ gauge theory framework and point out that $\Delta S=2\mathrm{}$ transitions do not provide at present too much of a constraint on these models. We suggest that neutral-current interactions and high-energy neutrino cross sections will test the validity of these theories.