two-state vector formalism

The two-state vector formalism provides a time-symmetric description of quantum mechanics, and is constructed such as to be time-reversal invariant.

The two-state vector formalism has similarities with the transactional interpretation of quantum mechanics proposed by John G. Cramer in 1986.

This work was motivated by Aharonov's long time quest to experimentally verify his theory that apparently random events in quantum mechanics are caused by events in the future (two-state vector formalism).

The transactional interpretation has similarities with the two-state vector formalism (TSVF) which has its origin in work by Yakir Aharonov, Peter Bergmann and Joel Lebowitz of 1964.

The two-state vector formalism (TSVF) is a description of quantum mechanics in terms of a causal relation in which the present is caused by quantum states of the past and of the future taken in combination.

The foundations for the two-state vector formalism were laid by Yakir Aharonov, Peter Bergmann and Joel Lebowitz in 1964, who considered measurements that were performed between other measurements, the results of which were known.