TITLE : Early universe, primordial black holes and generation of matter-antimatter asymmetry


The universe was extremely hot and dense when its age was less than 10^{-30} seconds. During such a phase, thermodynamic fluctuations naturally produce primordial black holes within causally connected regions of space-time. Primordial black hole production is very different from the black hole generation from astrophysical processes (which are related to the death of massive stars). The masses of primordial black holes created in the early universe are much less compared to the Sun's mass. Moreover, from the point of view of symmetry, one expects that during the big bang, equal amounts of matter and antimatter were created. However, today we see matter to be the only dominant cosmic player on large scales, the observed fraction of anti-matter being negligible. Can one invoke the primordial black holes to be responsible for the observed matter-antimatter asymmetry? In this talk, I will describe the basic physics that underlies the possibility of a net matter production from the evaporation of primordial black holes resulting from Hawking radiation.


Speaker: Prof. Patrick Das Gupta

Venue: Online

Date and Time: October 22nd, 2021, 4:30 pm