Beschreibung
First edition, complete journal issue in original printed wrappers, of Thomson and Reid's experimental confirmation of de Broglie's wave-particle duality, carried out independently of similar experiments by Davisson and Germer at Bell labs in New York. Davisson and Thomson shared the Nobel Prize for Physics in 1937, for the "experimental discovery of the diffraction of electrons by crystals." Born in 1892, the son of the physicist Sir J. J. Thomson, G. P. Thomson studied at Trinity College, Cambridge. Following a post at Cambridge, G. P. became Professor of Natural Philosophy at the University of Aberdeen in 1922 and remained there until 1930. It was at Aberdeen that G. P. began to carry out experiments revealing the phenomena of electron diffraction, assisted by one of his students, Alexander Reid. In this paper, Reid and Thomson describe the rings formed when a beam of cathode rays was sent at normal incidence through a thin film of celluloid and struck a photograph plate placed some distance behind the film. These were attributed to a diffraction of the cathode rays by the film, the cathode rays behaving as waves of wave-length h/mv according to de Broglie's theory of wave mechanics, and regularities in the structure of the film, or in the size of the molecules, making it behave as a kind of diffraction grating (Abstract). "Thomson arrived at his discovery in Aberdeen at about the same time as Davisson in New York. They announced their discoveries simultaneously in the same volume 119 of the journal Nature. However, the experimental approach and the manner in which the diffraction was observed were completely different in the two camps. Davisson's discovery was accidental, whereas Thomson, inspired by the theory of de Broglie, set out from the start to prove the wave nature of the electron . . . Quite opposite to the approach used by Davisson and Germer, who measured a beam of low energy electrons (54 eV) as these deflected off the atomic plane of the crystal surface, Thomson and Reid used a beam of relatively high-energy electrons (20,000 to 60,000 eV), which would pass directly through the crystalline lattice of thin metal foils . . . Thomson thus demonstrated the de Broglie matter wave. The materials tested by Thomson were polycrystalline meaning that the substance is built up of many crystals having different orientations, such as a powdered sample of single crystal grains. The effect of X-ray or electron diffraction of polycrystalline materials is the production of a diffraction pattern consisting of several concentric rings of various diameters about the central spot produced by the electron beam" (L'Annunziata, Radioactivity: Introduction and History, From the Quantum to Quarks, pp. 431-2). 8vo, pp. cxciii-cxcvi, 881-912, cxcvii-cc. Complete journal issue in original printed wrappers (a little soiled, corners a little worn, library ink stamp in upper margin of front wrapper). Bestandsnummer des Verkäufers ABE-1473961242064
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