Evan James Williams
Evan James Williams , mostly quoted EJ Williams, (born August 8, 1903 in Cwmsychpant near Llanybydder in Carmarthenshire , Wales ; † 1945 ) was a Welsh physicist.
Life
Williams attended Llandysul County School (where he excelled in both literature and science) and studied on a scholarship won in 1919 at the University of Wales at Swansea , where he made his master's degree in 1924. He then went to William Lawrence Bragg at the University of Manchester (with whom he later published) and then to Cambridge University , where he received his doctorate in 1929 (Ph.D.). In 1930 he also received a D.Sc. the University of Wales. In 1933 he was at the Niels Bohr Institute in Copenhagen , where he worked with Milton Plesset , among others . After returning to the UK, he became an Assistant Lecturer at the University of Manchester and then a Senior Lecturer at the University of Liverpool . In 1938 he became a professor at the University of Wales at Aberystwyth , where he remained until his death. During the Second World War he worked for the Department of Aviation and the British Admiralty in anti-submarine defense.
plant
Williams worked both experimentally and theoretically. He discovered the decay of the muon (observations in a bubble chamber with G. E. Roberts) and is known for the Weizsäcker-Williams method (with Carl Friedrich von Weizsäcker , who published it independently in 1934 before Williams and whom Williams also met in Copenhagen in 1933 near Bohr ) for the treatment of bremsstrahlung, for example, fast electrons in matter, in which the electric field is replaced by virtual photons. Williams was particularly interested in the scattering problem in quantum mechanics, which he wanted to deal with as clearly as possible using classical methods. In 1948, Niels Bohr wrote a review article on the interaction of high-energy charged particles with matter, which, as he wrote in the article, he originally wanted to write with Williams, which prevented Williams' early death.
In 1939 he became a Fellow of the Royal Society .
Web links
- Biography and photo on the BBC
- Brief biography on a page from archives in Wales
- John David Jackson: Examples of the zeroth theorem in the history of Physics . 2007, with a biography of Williams, arxiv : 0708.4249
Individual evidence
- ^ Roberts, Williams: Evidence for the Transformation of mesontrons into electrons . In: Nature , Volume 145, 1940, p. 102, 818. The mesotron means the muon, which at that time was not exactly differentiated from other particles called mesons. Shortly thereafter, Japanese physicists and Robert Marshak postulated that there were several mesons . See, for example, Owen Lock: Discovery of the Pion . In: CERN Courier, 1997.
- ↑ Williams: Nature of high energy particles of penetrating radiation and status of ionization and radiation formula . In: Physical Review , Volume 45, 1934, p. 729
- ↑ Jackson pointed out that Enrico Fermi used the basic principle of the method as early as 1924
- ^ Williams: Application of ordinary space-time concepts in collision problems and relation of classical theory to Born's approximation . In: Reviews of Modern Physics , Volume 17, 1945, pp. 217-226
| personal data | |
|---|---|
| SURNAME | Williams, Evan James |
| ALTERNATIVE NAMES | William, EJ |
| BRIEF DESCRIPTION | Welsh physicist |
| DATE OF BIRTH | August 8, 1903 |
| PLACE OF BIRTH | Cwmsychpant at Llanybydder , Carmarthenshire , Wales |
| DATE OF DEATH | 1945 |