MSGSS
Admissible Black Hole and Cosmological Geometries in Teleparallel Gravity
Einstein taught us that gravity is geometry: matter curves spacetime, and light and planets follow the straightest possible paths. His theory has passed a remarkable range of tests, but puzzles like dark energy and dark matter have inspired alternatives. Before these theories can resolve those puzzles, they must answer a fundamental question: can they describe the black holes and the universe we observe? In this talk, I explore teleparallel gravity, where torsion provides an alternative description of gravity. Because the field equations are difficult to solve directly, I turn the problem around: starting from observations and geometric features shared with Einstein’s theory, I ask which theories admit geometries with those features. The answer depends on a hidden part of the geometry that ordinary distances do not reveal. I will show how this structure determines which black hole and cosmological geometries are allowed, and which theories cannot accommodate them.