Retrocausality is claimed to occur in some psychic phenomena such as precognition. J. W. Dunne 's 1927 book An Experiment with Time studied precognitive dreams and has become a definitive classic. Parapsychologist J. B. Rhine and colleagues made intensive investigations during the mid-twentieth century. His successor Helmut Schmidt presented quantum mechanical justifications for retrocausality, eventually claiming that experiments had demonstrated the ability to manipulate radioactive decay through retrocausal psychokinesis. Such results and their underlying theories have been rejected by the mainstream scientific community and are widely accepted as pseudoscience, although they continue to have some support from fringe science sources.