Speaker
Digesh Raut
(University of Delaware)
Description
We propose a $SU(5) \times U(1)_{PQ}$ Majoron-axion model free of the axion domain wall, axion dark matter isocurvature, and $SU(5)$ monopole problems. The vectorlike fermions in the model are essential to achieving successful unification of the SM gauge couplings as well as the viability of the inflation scenarios. The $SU(5)$ symmetry is broken at $M_{GUT} \simeq (4-7)\times 10^{15}$ GeV and the proton lifetime $\tau_p$ is estimated to be well within the expected sensitivity of the future Hyper-Kamiokande experiment, $\tau_p \lesssim 1.3 \times 10^{35}$ years. Meanwhile, the CASPEr experiment can search for the axion.
