Speaker
Description
Gravitational lensing, i.e. the deflection of propagating signals by spacetime curvature is one key prediction of General Relativity. Besides this intrinsic interest as a fundamental prediction, this effect has become one crucial probe used by the cosmology community to identify and map dark matter.
Relying on the idea that the propagation of both electromagnetic and gravitational waves (GW) signals is analogous, it is tempting to think that these two types of signals obey the same type of gravitational lensing. However, I will argue why this idea is insufficient when wave-optics effects are taken into account, e.g. diffraction. I will illustrate how GW lensing differs from the usual lensing formalism and discuss its relevance, challenges and opportunities for cosmology with GW.
