HEP Theory2026-06-151 minarXiv:2606.16986expressHow to Weigh a Black Hole Through the Geometry of Its ShadowA black hole is not just a dark spot in the sky. It is a complex object whose properties depend on the geometry of spacetime around it.Davide Cassani·Enrico TurettaFirst law of black hole mechanicsBekenstein-Hawking entropyJacob BekensteinStephen HawkingAdam Riessblack holeblack hole merger👍👎☆SimplePopularAdvanced