In 1936 van Stockum solved the Einstein equations for the gravitational field of a rapidly rotating infinite cylinder. It is shown that such a field violates causality, in the sense that it allows a closed timelike line to connect any two events in spacetime. This suggests that a finite rotating cylinder would also act as a time machine.
- Received 6 November 1973
- Published in the issue dated 15 April 1974
© 1974 The American Physical Society