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Sir Joseph John Thomson

Cheetham 18.December.1856 - Cambridge 30.August.1940
1897  Discovered of the electron

Physical, well-known for his experimental studies on the electron, in 1906 it obtained the Nobel Prize for his researches for the electric conductibility of the gases. Five years after the formulation of the electronic theory of the matter, Thomson "discovers" the electron. In fact it is not about a true and own discovery, since Thomson was already more than convinced about the validity of the theories relative to the bearers of office, and he tries to make observations that could give numerical values to the parameters of these corpuscles, him definite "elementary atoms"; then it would be more demanded to say that he has demonstrated the existence of the electron. His studies, which are a marriage between complex theories and as complex experiments, in the detail of which we do not enter, continue for many years, and there come all made close to the center of experimental researches of Cambridge, entitled to Lord H.Cavendish, Thomson of which has become a director to suns twenty eight years. His researches leave from the study on the rarefied gases, in which it looks for the correlation between the laws of the electromagnetism and the structure of the matter, investigating the cathode rays that he was keeping, contrarily to the German, material physiques, and able to mark the trajectories of particles of matter, offices of negative electricity. The existence of these particles is verified after a series of experiments. At Thomson the doubt remains nevertheless about the nature of these particles, or rather if there were atoms, or molecules, or something of even less, and in 1897 he leads a series of experiments on the value of the report between the mass and the office of the particles constituted the cathode rays, arriving at the conclusion of the existence of "a new state of the matter, in whom all the matter is of an alone family, and this matter is the substance with whom all the chemical elements are built". In a memory of 1904 it suggests the idea of the atom without nucleus; later on it was refuted by Rutherford with the data of the experiment of Geiger and Marsdem.