4 research outputs found
Quantum Fluctuations around the Electroweak Sphaleron
We present an analysis of the quantum fluctuations around the electroweak
sphaleron and calculate the associated determinant which gives the 1--loop
correction to the sphaleron transition rate. The calculation differs in various
technical aspects from a previous analysis by Carson et al. so that it can be
considered as independent. The numerical results differ also -- by several
orders of magnitude -- from those of this previous analysis; we find that the
sphaleron transition rate is much less suppressed than found previously.Comment: DO-TH-93/19 39 pages, 5 figures (available on request as Postscript
files or via Fax or mail), LaTeX, no macros neede
Models of Neutrino Masses and Baryogenesis
Majorana masses of the neutrino implies lepton number violation and is
intimately related to the lepton asymmetry of the universe, which gets related
to the baryon asymmetry of the universe in the presence of the sphalerons
during the electroweak phase transition. Assuming that the baryon asymmetry of
the universe is generated before the electroweak phase transition, it is
possible to dicriminate different classes of models of neutrino masses. While
see-saw mechanism and the triplet higgs mechanism are preferred, the Zee-type
radiative models and the R-parity breaking models requires additional inputs to
generate baryon asymmetry of the universe during the electroweak phase
transition.Comment: 27 pages including 5 figures; Review article for Pramana: the Indian
Journal of Physic
Structure of the Quark Propagator at High Temperature
In the high temperature, chirally invariant phase of QCD, the quark
propagator is shown to have two sets of poles with different dispersion
relations. A reflection property in momentum space relates all derivatives at
zero-momentum of the particle and hole energies, the particle and hole damping
rates, and the particle and hole residues. No use is made of perturbation
theory.Comment: 8 pages, Latex twocolum