As a member of the LIGO-Virgo-KAGRA (LVK) collaboration, a network of terrestrial gravitational wave observatories, L2IT actively participated (through Vasco Gennari, PhD student at the University of Toulouse and member of L2IT) in the analysis of an exceptionally noisy gravitational wave signal detected in 2025, 10 years after the first gravitational wave detections. The origin of this signal is attributed to two black holes slowly spiraling together until they merged to form a single black hole.
The clarity of the detected signal made it possible to observe the system even during the phase following the merger, thereby pushing back the limits of our knowledge of gravity. The results of the analysis of this merger, published in the renowned journal Physical Review Letters [1], show that Stephen Hawking’s theorem predicting that a black hole cannot decrease in its area is consistent with the properties measured in this observation. Further analysis also suggests, 60 years after its proposal, that Kerr’s description of Einstein’s theory of general relativity remains valid under conditions of extreme gravity. An article by the LVK collaboration, of which Vasco was one of the main authors, has been submitted for publication in the same journal.
To accompany LVK’s latest analyses, the Gravitational Wave Open Science Center, developed in part by L2IT (through Mathieu Dubois, CNRS research engineer and member of L2IT), has been updated with the latest gravitational wave data and the tools to analyze it [2]. Feel free to explore yourself!
[1] https://journals.aps.org/prl/abstract/10.1103/kw5g-d732
[2] https://www.virgo-gw.eu/news/gwtc-4-0-updated-gravitational-wave-catalog-released/
Image credit: Aurore Simonnet (SSU/EdEon)/LVK/URI
