Solutions to large B and L breaking in the Randall-Sundrum model

摘要

The stability of proton and neutrino masses are discussed in theRandall-Sundrum model. We show that relevant operators should be suppressed, ifthe hierarchical Yukawa matrices are explained only by configurations ofwavefunctions for fermions and the Higgs field along the extra dimension. Weassume a $Z_N$ discrete gauge symmetry to suppress those operators. In theDirac neutrino case, there is an infinite number of symmetries which may forbidthe dangerous operators. In the Majorana neutrino case, the discrete gaugesymmetries should originate from $U(1)_X$ gauge symmetries which are broken onthe Planck brane. We also comment on the $n-\bar{n}$ oscillation as aphenomenon which can distinguish those discrete gauge symmetries.