A supertask consists in the performance of an infinite number of actions in a finite time. I show that any attempt to carry out a supertask will produce a divergence of the curvature of spacetime, resulting in the formation of a black hole. I maintain that supertasks, contrarily to a popular view among philosophers, are physically impossible. Supertasks, literally, collapse under their own weight.
Categories: physics.hist-ph gr-qc