We investigate the physics of an ensemble of oscillating neutrinos in the primordial plasma of the early Universe. The result is a coupled set of quantum kinetic equations both for the neutrino density operator and the momentum distributions of other species in the plasma. In the appropriate momentum-averaged limit, a comparable set of quantum rate equations arises. For the case of oscillations within the weakly interacting sector we find surprising new contributions to the forward scattering effective potential, as well as new quantum contributions to the kinetic and/or rate equations. The possibility that neutrino oscillations might affect primordial nucleosynthesis is discussed. PACS numberk): 98.80. Cq, 14.60.Lm, 95.30.Cq

No abstract

We show that there is an analogous Aharonov-Casher topological effect on a neutral particle with electric dipole moment interacting with a magnetic field produced by magnetic monopoles.

No abstract

We have made a systematic study of the electric dipole moment (EDM) of neutron Dn in various models of CP violation. We find that (i) in the standard KM model with 3 families, the neutron EDM is in the range 1.4 × 10−33 ≤ |Dn| ≤ 1.6 × 10−31 e.cm , (ii) the two Higgs doublet model has approximately the same value of Dn as the standard model, (iii) Dn in the Weinberg model is predicted to satisfy |Dn| > 10−25 e.cm , (iv) in a class of left-right symmetric models Dn is of the order of 10−26±1 e.cm , (v) in supersymmetric models, Dn is of order 10−22ϕ e.cm with ϕ being the possible phase difference of gluino mass and the gluino-quark-squark mixing matrix, (vi)the strong CP parameter θ is found to be θ < 10−9, using the present experimental limit that |Dn| < 2.6 × 10−25 e.cm with 90% confidence.