Speaker
Stylianos Papadopoulos
Description
We investigate the generation of gravitational waves from scalar perturbations at second order in a matter-dominated Friedmann–Robertson–Walker (FRW) universe. Since the representation of gravitational waves in perturbation theory is gauge-dependent, identifying gauge-invariant quantities becomes essential for a physically meaningful interpretation. This leads us to define a new tensor amplitude that is both transverse-traceless and gauge-invariant at second order, and can be interpreted as the physical gravitational wave. Finally, we are attempting to study the geometrical interpretation and hypothesize that it acts as a potential for the B-modes of the Weyl tensor.
Primary authors
Ruth Durrer
(DPT Université de Genève)
Stylianos Papadopoulos
