Speaker
Description
One of the greatest outstanding mysteries in physics is the observed baryon asymmetry of the Universe. Experimental constraints have made it clear that neither CP asymmetry in the quark sector, nor CP asymmetry in the lepton sector, are sufficient to explain the size of the observed baryon asymmetry. One viable explanation is the leptogenesis mechanism of Fukugita and Yanagida wherein lepton asymmetry originates in the early universe through out-of-equillibrium decays of heavy right handed neutrinos. This is then in turn converted into baryon asymmetry via the sphaleron process. We present an leptonic mass Lagrangian containing 3 heavy right handed neutrinos which leads to the required degenerate Majorana mass matrix neccescary for leptogenesis. It is also constructed so that it is diagonalizeable by a PMNS matrix whose value’s magnitudes are within 1-sigma of current experimental values. This is done by deviating from a Lagrangian whose mass matrix diagonalable by TM2. We then investigate some of the phenomenological consequences of this model.
