Webinar
Title: Gravitational waves and proton decay: complementary windows into grand unification
Speaker: Dr. Ye-Ling Zhou (周也铃) (Southampton U., UK)
Time: 15:30 (Beijing Time), Thursday, 2020-6-11
Zoom: https://zoom.us/j/2151583083
Zoom ID:2151583083
Abstract: Proton decay is a smoking gun signature of Grand Unified Theories (GUTs). Neutrino oscillation experiments provide the best constraints to the proton decay and limits on the GUT symmetry breaking scale. Another possible observational consequence of GUTs is the formation of a cosmic string network produced during the GUT breaking. The evolution of such a network in the expanding Universe produces a stochastic gravitational wave (GW) background which will be tested by a number of GW detectors over a wide frequency range. I will discuss the non-trivial complementarity between observing proton decay and GWs produced from cosmic strings in SO(10) GUTs. Searches for proton decay and GWs can set lower and upper bounds of some intermediate scales of GUT breaking, respectively. We show that such observations could exclude SO(10) breaking via flipped SU(5) x U(1) or standard SU(5), while breaking via a Pati-Salam intermediate symmetry, or standard SU(5) x U(1), may be favoured if a large separation of energy scales associated with proton decay and cosmic strings is indicated. Talk based on 2005.13549.
