Ordinarily, a single beta decay permits a neutron to assume a less energetic state.
Having already uncovered a profound link between the electromagnetic force that governs electricity and magnetism and the weak force that acts in such processes as beta decay, physicists have been constructing so-called grand unified theories that go even further.
The effect of this in beta decay would not show up in first order in the weak interaction either.
Limits on the CP-Violating Coupling Constants From Beta Decay Experiments
LR]-interaction can be represented for beta decay by contact nonderivative four-fermion interactions.