Selection Rules in Weak Interaction and Conservation of Fermion Quantum Number

Abstract

Traditionally, in weak interaction, I 3 , Y and four flavour quantum numbers are not conserved but several empirical selection rules work well. Recently, it was found that, in weak interaction, there are three levels of conservation of additive quantum numbers, and fermion quantum number F is conserved in all kinds of interactions. It is known that weak interaction has three types: fermionic, pure hadronic and pure leptonic, corresponding to the first and the second level of conservation of additive quantum numbers respectively. It is demonstrated in this paper that the selection rules in all types of weak interaction can be interpreted by conservation of F , and the formula of relation between Q/e , F and F 0 is more general than Gell-Mann-Nishijima formula. Description of weak interaction becomes simpler, If only we take Q , F 0 and F , based on the conserved physical quantities.