Practically stable proton in the SU-5 model

Permutations and mixing of the fermion right comonents from different generations, in the SU5-model with an additional Higgs 45-let, could lead to substantial changes of both the proton lifetime and the relationships between the probabilities of proton decay different channels. In the presence of solely three known fermian generations the upper limit of the proton lifetime, tausub(p)sup(max) approximately equal to 1034 to 10 37 years, is defined by the Kobayashi-Maskava angles and their experimental errors. At this the dominant channel is a difficulty detectable p → #betta#X channel. The ultimate versions of mixing correspond to the longest proton lifetime and sUppression of readily detectable decay modes. In view of principial difficulties of revealing the proton instability with tausub(p) > or approximately 1034 years, the lifetimes for the ultimate versions imply a practically stable proton. By varying the mixing angles one could obtain an arbitrary proton lifetime between the prediction of both the standard SU5 model and ultimate versions. All conclusions drawn to apply to the neutron decay with the baryonic number violation as well