Time reversal may refer to:

• In physics, T-symmetry - the study of thermodynamics and the symmetry of certain physical laws where the concept of time is reversed — ie. where a mirror (reverse) transformation is applied to a forward direction time state.

• Time Reversal Signal Processing - a signal processing technique popular in acoustics, and currently being applied to electromagnetics, that results from the reversal in time of a system's response signal.

• Time travel - theorised and speculative concepts about travelling physically through time.

This disambiguation page lists articles associated with the same title. If an internal link led you here, you may wish to change the link to point directly to the intended article.