Multiplicative baryon-number conservation and the oscillation of hydrogen into antihydrogen

Abstract

Interactions are considered that would allow the transformation of baryons into leptons with a multiplicative conservation law. One such interaction would transform hydrogen atoms into antihydrogen atoms. It is shown that on the basis of nonobservation of annihilation gamma rays from hydrogen-antihydrogen annihilation in HI regions of our galaxy, an upper limit for the strength of such interactions is ${10}^{-21\mathrm{}}$ $G_F$. Other sources of upper limits on such interactions are presented also.