dr Adam Smetana (Institute of Experimental and Applied Physics, CTU in Prague)

Role of neutrinos in the electroweak symmetry breaking

The condensation of known fermions is an appealing idea for explaining the electroweak symmetry breaking (EWSB) already since early eighties. It is natural to treat the top-quark condensate as the only non-negligible source of EWSB as the top quark dominates the fermion mass spectrum. However many realistic models of this kind have failed in reproducing the correct spectrum of masses of the top-quark and of the W, Z and Higgs bosons. We study the role of neutrino condensation. If a seesaw mechanism applies for the neutrino masses, the Dirac mass and the corresponding neutrino condensate may be significantly strong source of the electroweak symmetry breaking comparable to that of top-quark. Within the simplistic model we show that the number of right-handed neutrinos needed for meeting phenomenological requirements is very large, O(100).