When: Wednesday, November 15, 2023, 3:30 PM - 5:00 PMWhere: Physics (G. O. Jones building) Room 516, Mile End
Speaker: Subodh Patil (Leiden)
Divergences arise all the time in statistical and quantum field theoretic settings and we have a very well defined prescription how to deal with them on time independent backgrounds. This prescription also transposes to time dependent backgrounds, provided we're mindful of a range of important caveats. Following through on this in detail, however, can throw up some surprises which I will discuss in this talk, with cautionary implications for: The uses (and abuses) of effective potentials in cosmology, the size of loop corrections during inflation, the role played by the beginning and end of inflation vis a vis divergences, and important caveats on how vacuum tensor perturbations imprint on cosmological observables.