Chang Kee Jung, Professor of Physics, State University of New York at Stony Brook
Abstract:
Matter-antimatter asymmetry is one of the most outstanding mysteries of
the universe that provided a necessary condition to our own existence.
There have been various attempts to solve this mystery including
'Baryogenesis' hypothesis. However, the B-factory experiments
during the last decades showed that the observed CP-violation
in the quark sector is not big enough for baryogenesis
to be a viable solution to the matter-antimatter asymmetry.
This leads us to the 'Leptogenesis' hypothesis,
in which CP-violation in the lepton section plays a crtical role to create
the matter-antimater asymmetry at the onset of the Big Bang.
Thus, experimental observation of CP-violation in the lepton
sector could prove to be tantamount to one of the most important
discoveries in our understanding of the universe.
Recently the T2K experiment published a result that indicates a non-zero
$\theta_{13}$, the last unknown mixing angle in the lepton sector,
at 2.5 sigma level of significance. In this talk I will present the details of
this result and its importance to the possible future CP-violation
measurements in the lepton sector. I will also describe the T2K experiment
in some detail, and present other recent results.