Seminarium Teorii Względności i Grawitacji

Quantum cosmological models are commonly described by means of semiclassical approximations that may smooth out important effects to include which a more detailed treatment is needed. I will first try to define the general framework of primordial fields in quantum spacetimes that may be employed in theories of the origin of primordial structures in the Universe. Then I will discuss the role of quantum uncertainties of the background geometry in the propagation of fields. I will investigate the extent to which the uncertainties may affect the primordial amplitude of gravitational waves. Making use of the WKB approximation I will derive an analytical formula for the amplitude spectrum as a function of the quantum dispersion of the background spacetime. Zoom Meeting ID: 814 7211 6408 Passcode: 795365