On Cabibbo angle from theory

We find an expression for the Cabibbo angle from quark flavour generators of the first two generations. The flavour generators operate on the toroidal components in an intrinsic dynamics for colour degrees of freedom. The generators have led to parton distributions for u and d valence quarks of the proton that compare well with those derived from experiment. The present result $0.974996\ldots$ for the cosine of the Cabibbo angle compares rather well with the experimentally established value for the up-down quark mixing element 0.97420+/−0.00021 of the Cabibbo-Kobayashi-Maskawa matrix