Seminar of Theoretical Physics - Peter Mészáros (10.3.2020)
Tuesday 10.3.2020, at 14:00 hod., Lecture room F2/125
Peter Mészáros:
Nonlinear effects in creation of primordial cosmological perturbations
Abstract:
Primordial gravitational waves have not been directly detected in polarization of the cosmic microwave background yet. However, they can leave an imprint on other perturbations, providing an alternative way of their detection. I will talk about nonlinear effects leading to formation of this imprint and elaborate on its observability. This is related to relations for perturbations in relativistic cosmology analogous to Ward-Takahashi identities known in quantum electrodynamics. In the second part I will briefly explain how to calculate the mentioned effect, as well as other nonlinear effects influencing cosmological perturbations in the early universe. Finally, I will summarize results of such calculations on one specific model of cosmological inflation.