Val Logsdon FitchVal Logsdon Fitch 1923
– is an American nuclear physicist. Fitch and co-researcher James Watson Cronin
were awarded the 1980 Nobel Prize in Physics
for a 1964 experiment that proved that certain subatomic reactions do not adhere to fundamental symmetry principles. Specifically, they proved, by examining the decay of K-mesons, that a reaction run in reverse does not merely retrace the path of the original reaction, which showed that the reactions of subatomic particles are not indifferent to time.