Testing General Relativity with Black Holes

Abstract

The theory of General Relativity has successfully passed a large number of observational tests. The theory has been extensively tested in the weak-field regime with experiments in the Solar System and observations of binary pulsars. The past 10 years have seen significant advancements in the study of the strong-field regime, which can now be tested with gravitational waves, X-ray data, and black hole imaging. Here I summarize the state-of-the-art of the tests of General Relativity with black hole X-ray data and I briefly discuss the long-term vision of the possibility of an interstellar mission to the closest black hole for more precise and accurate tests.

arXiv comment9 pages, 2 figures. v2: refereed version. Talk given at the International Conference on Theoretical Physics and Astrophysics (ICTPA-2025), 24-28 March 2025, Tashkent, Uzbekistan

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