25 Facts About Seth Neddermeyer

Seth Henry Neddermeyer was an American physicist who co-discovered the muon, and later championed the implosion-type nuclear weapon while working on the Manhattan Project at the Los Alamos Laboratory during World War II.

Seth Henry Neddermeyer was born in Richmond, Michigan, on September 16,1907.

Seth Neddermeyer attended Olivet College, a small college that his mother, older sister, and uncle had attended, for two years before his family moved to California.

Seth Neddermeyer transferred to Stanford University, from which received his Bachelor of Arts degree in 1929.

Seth Neddermeyer confirmed the theory espoused by Niels Bohr for this process.

Seth Neddermeyer noted large radiative energy losses of electrons in lead, in agreement with the theory propounded by Hans Bethe and Walter Heitler.

Anderson and Seth Neddermeyer collaborated with Millikan in high altitude studies of cosmic rays, which confirmed Robert Oppenheimer's theory that the air showers produced in the atmosphere by cosmic rays contained electrons.

In early 1941, with World War II raging in Europe but the United States not yet a belligerent, Neddermeyer joined a team led by Charles C Lauritsen and William A Fowler at the Department of Terrestrial Magnetism at the Carnegie Institution of Washington, and then at the National Bureau of Standards in Washington, DC, that worked on the photoelectric proximity fuze.

Seth Neddermeyer was an early advocate for the development of an implosion technique for assembling a critical mass in an atomic bomb.

Unable to find much initial enthusiasm for the concept among his fellow Los Alamos scientists, Seth Neddermeyer presented the first substantial technical analysis of implosion in late April 1943.

Seth Neddermeyer's group became the E-5 Group, which was part of Captain William S Parsons' E Division.

Seth Neddermeyer embarked on an intensive series of experiments testing cylindrical implosions.

Seth Neddermeyer was replaced as the head of the E-5 Group by Kistiakowsky on June 15,1944, but remained a technical adviser to the implosion program, with group leader status.

Seth Neddermeyer was said to have been much embittered by this episode.

In Oppenheimer's August 1944 reorganization of the Los Alamos Laboratory, Seth Neddermeyer's group was renamed X-1, with Norris Bradbury as group leader.

The implosion method championed by Seth Neddermeyer was used in the first atom bomb exploded, the Fat Man bomb dropped on Nagasaki, and almost all modern nuclear weapons.

In 1946, after World War II ended, Seth Neddermeyer left Los Alamos to become an associate professor at the University of Washington, where he would spend the rest of his career.

Seth Neddermeyer resumed his studies of cosmic rays using a cloud chamber and a new device that he invented to measure the speed of charged particles known as a "chronotron".

Seth Neddermeyer was particularly interested in the properties of the muon, and conducted experiments with muons at SLAC.

Seth Neddermeyer participated in the DUMAND Project, for which he helped design large-scale underwater neutrino detectors.

Seth Neddermeyer became interested in parapsychology, insisting, in spite of the skepticism of many colleagues, that it warranted proper scientific investigation.

Seth Neddermeyer retired in 1973, becoming a professor emeritus, but he continued his research activities for as long as his health permitted.

In later life, Seth Neddermeyer was sometimes troubled by the nuclear weapons he had helped to invent.

Seth Neddermeyer died in Seattle on January 29,1988, from complications of Parkinson's disease.

Seth Neddermeyer is portrayed by Colin Bennett in the 1980 BBC series Oppenheimer, by Joe D'Angerio in Fat Man and Little Boy, and by Devon Bostick in the Christopher Nolan-directed film Oppenheimer.