HE Seminar - 10/20/23 - Soubhik Kumar - New York University

This week's High Energy Lunchtime Seminar was presented by Dr. Soubhik Kumar from New York Univerity. The title of his talk is, “Rare Processes during Inflation: CMB Hotspots
and Early Galaxies.”

Abstract: Superheavy particles can be produced during the inflationary era of the primordial Universe. Owing to their large mass, they are produced rarely. However, once produced, they can give rise to significant perturbations in the spacetime metric around their locations. Such perturbations eventually would give rise to overdensities in the primordial plasma. I will describe two late-time signatures of such overdensities: (i) hotspots on the cosmic microwave background, and (ii) anomalously massive early galaxies. I will also demonstrate that novel search strategies are required to look for such signatures and those would constitute one of the unique probes of particle physics at very high energies.