The two-state vector formalism has similarities with the transactional interpretation of quantum mechanics proposed by John G. Cramer in 1986, although Ruth Kastner has argued that the two interpretations (Transactional and Two-State Vector) have important differences as well. It shares the property of time symmetry with the Wheeler–Feynman absorber theory by Richard Feynman and John Archibald Wheeler and with the time-symmetric theories of Kenneth B. Wharton and Michael B. Heaney