Chakravarti, KabirKabirChakravartiGhosh, RajesRajesGhoshSarkar, SudiptaSudiptaSarkar2025-08-222025-08-222022-01-012331-8422http://arxiv.org/abs/2201.08700https://d8.irins.org/handle/IITG2025/18431Recent gravitational wave observation based on the data from GW150914 has firmly confirmed Hawking's area theorem and estimated the increase in total horizon area during a merger process of two Kerr black holes. We use this result to obtain the first observational bound on the 4D topological Gauss-Bonnet coupling as γ≲γmax≈2.804+3.739−2.804×109m2 at 90% credibility.en-USBoundingBoundlessGauss-Bonnet CouplingGeneral RelativityQuantum Cosmologye-Printe-Print123456789/615