String Theory seminar - Sravan Kumar Seminar

Abstract: Unitarity and renormalizability are the two most important tools to guide us toward UV completion of gravity. In this view, I will discuss two types of spacetime non-localities that play a crucial role in our understanding of gravity at the short distance scales and at the horizon scales. The first kind of non-locality is associated with non-point-like interactions of fundamental degrees of freedom towards the Planck scales. I will present in detail the implications of this non-locality to the early Universe cosmology and to the primordial gravitational waves. The second non-locality is associated with the nature of quantum fields in curved spacetime. In this regard, I will present a new formulation of a unitary quantum field theory in curved space-time with its observational signatures in the context of inflationary cosmology and its implications for the understanding of black hole evaporation.