Bounds from a Gaussian Universe

by Subodh Patil (CERN)

Monday 24 Nov 2014, 14:00 → 15:00 Europe/Zurich

EPFL, Cubotron 727

Although detecting primordial non-Gaussianity (NG) would provide an incredibly rich window onto the interaction physics of the inflaton, one might wonder what we could conclude about its nature if all we end up observing is consistent with adiabatic, Gaussian, scale invariant initial conditions. In this talk we highlight how in principle, one can still infer a great deal. If one were to assume nothing other than adiabaticity in the early universe, we discuss how one can use the absence of primordial NG to place bounds on primordial expansion history, allowing us in principle to rule out certain non-standard models of the early universe. More interestingly from a phenomenological perspective, the absence of primordial NG can furthermore be used to place bounds on various hidden sector scenarios that become more and more meaningful the more stringent the observational bounds become. We discuss the implications for various string theoretic and supersymmetric phenomenological scenarios and prospects from future observations.