Recently, the LIGO-Virgo-KAGRA collaboration hosted one of its biannual meetings in Barcelona from September 23-26, 2024. The goal was to gather many members of the collaboration working on a vast variety of topics from theory to instrumentation to discuss the progress of the ongoing fourth observing run, and plans for the future of the detectors.

Throughout the meeting, Strong Group members Juno Chan, Jose Maria Ezquiaga, Rico Lo, Elisa Maggio and Luka Vujeva participated in a variety of activities, such as chairing sessions, giving presentations and presenting posters. We discussed tests of general relativity, the detection of strongly lensed gravitational waves, as well as how these detections are affected by the structure of the lenses. During the poster session, Luka Vujeva’s poster received an honorable mention from the selection committee in the theory section.