Abstract:
Neutrino oscillation experiments have provided the convincing evidence
for very tiny,but non-zero masses of neutrinos. The origin of neutrino masses
requires new physics beyond the Standard Model of particle physics.
In this colloquium physics of the Standard Model extended by
right-handed neutrinos is discussed. This framework can potentially explain
the origins of neutrino masses, dark matter, and baryon asymmetry of the
Universe at the same time. The typical mass range of right-handed neutrinos
are within the reach of experiments and the direct (and indirect) tests of
the model are possible. We explain the recent progress of this framework and
experimental search for right-handed neutrinos.