ESI Workshop — Lensing and Wave Optics in Strong Gravity

Gravitational lensing represents a characteristic feature of astrophysical systems in strong gravitational fields, such as the supermassive black holes recently observed by the Event Horizon Telescope. On the other hand, strong gravitational fields are also being probed by the LIGO-Virgo-KAGRA observations of gravitational waves. With the rapidly increasing number of observed gravitational waves, it is expected that a small portion of these events will be gravitationally lensed. This workshop aims to bring together members of the astrophysical community working on lensing and wave effects in strong gravitational fields and to discuss physics relevant for both the Event Horizon Telescope and LIGO-Virgo-KAGRA observations. We plan to discuss the current open problems and perspectives in the field, facilitate the transfer of techniques between the much more mature field of lensing of electromagnetic waves towards novel studies in the lensing of gravitational waves, as well as to see how wave effects beyond the standard lensing approaches could be incorporated.