Ephraim Fischbach (born 1942) is an American physicist and a professor at Purdue University. He is best known for his attempts to find a fifth force of nature[1] and his research relating to the detection of neutrinos.[2] He has also done work relating to the prediction of solar flares[3] and the detection of radiation by cell phones.[4]
Fischbach studies variation in radioactive decay rates, suggesting that neutrino emission from the Sun reduces the rate of nuclear decay.[5] He reanalysed the Eötvös experiment, which he saw as evidence for a fifth physical force.[6] However, in 1992, he and Carrick Talmadge conducted an experiment which found no compelling evidence for a fifth force.[7]