Experimental Tests of BrokenŨ(12)and ApproximateU(6)×U(6)

Abstract

Broken $\tilde{U}\mathrm{}\left(12\right)\mathrm{}$ and the Dashen-Gell-Mann nonchiral $U\left(6\right)\mathrm{}\times U\left(6\right)\mathrm{}$ symmetry are shown to lead to equivalent predictions for a large number of processes. Predictions based on invariance under certain subgroups of $\tilde{U}\mathrm{}\left(12\right)\mathrm{}$ are shown to be valid in $\tilde{U}\mathrm{}\left(12\right)\mathrm{}$ calculations which include symmetry breaking to all orders by momentum spurions. New predictions from the $W$-spin collinear group include $M1\mathrm{}$ dominance for $N^{*}$ photo-production and electroproduction and justify the Stodolsky-Sakurai assumption of $M1\mathrm{}$ dominance in vector-meson-exchange peripheral reactions.