Investigations on the nature of light showed that, depending on the kind of experiment performed, light must be described by electromagnetic waves or by particles (photons). Thus the wave aspect appears in the context of diffraction and interference phenomena, whereas the particulate aspect shows up most distinctly in the photoelectric effect. So for light, the relations describing wave-particle duality are already known. But what about material particles? Their particulate nature is rather obvious; do they also possess a wave aspect?
KeywordsPermeability Manifold Sine Tate Azimuth
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- de Broglie, Prince Louis Victor, French physicist, 1892–1987, professor of theoretical physics at the Institut Henri Poincaré. He founded with his Ph.D. thesis “Recherches sur la Théorie des Quants” (1924) the theory of matter waves (de Broglie waves) and was awarded the Nobel Prize in Physics for it in 1929. Later he worked mainly on the development of the quantum theory of elementary particles (neutrino theory of light, wave theory of elementary particles) and proposed a new method for the treatment of wave equations with higher spin, the so-called fusion method. Google Scholar
- Davisson, Clinton Joseph, American physicist, * Bloomington (IL), 22.10.1881, † Charlottesville (VA), 1.2.1958. From 1917 to 1946 D. was a scientist at Bell Telephone Laboratories; then, until 1954, he was a professor at the University of Virginia in Charlottesville. In 1927 D. and L.H. Germer measured electron diffraction by crystals, a decisive proof of the wave nature of matter. In 1937 he was awarded the Nobel Prize in Physics.Google Scholar
- Laue, Max von, German physicist, * Pfaffendorf (near Koblenz, Germany), 9.10.1879, † Berlin, 24.4.1960. v.L. was a student of M. Planck, a professor in Zurich, Frankfurt, Berlin and, from 1946, Director of the Institut für Physikalische Chemie und Elektrochemie in Berlin-Dahlem. v.L. was the first director of the Institut für Theoretische Physik in Frankfurt (from 1914 until 1919), his successor being M. Born. His proposal to irradiate crystals with X-rays was performed by Walther Friedrich and Paul Knipping in late April 1912. L.’s immediate explanation of the X-ray interferences detected in this experiment won him the Nobel Prize in Physics in 1914. With this, the wave nature of X-rays as well as the spatial grating structure of crystals was established. As early as 1911, v.L. wrote a book about the theory of relativity, which was widely read, and in which he later included general relativity. He also worked on the applications of relativity, e.g. on thermodynamics. Further treatises covered superconductivity, glow-electron emission and the mechanism of amplifier valves. After 1933 v.L. tried, often successfully, to oppose the influence of national socialism on science in Germany.Google Scholar
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- Hilbert, David, * Königsberg, Germany (now USSR) 23.1.1862, † Göttingen 14.2.1943. H., son of a lawyer, studied in Königsberg and Heidelberg and became a professor in Königsberg in 1886. From 1895 on, he contributed to making Göttingen a world centre of mathematical research. The most important living mathematican, H. proved himself as a world-wide authority in his famous talk given in Paris in 1900, where he proposed 23 mathematical problems which interest mathematicians even today. H. contributed to many fields that have deeply influenced modern mathematical research, e.g. on the theory of invariants, group theory and the theory of algebraic manifolds. His investigations on number theory culminated in 1897 in his report, “Die Theorie der algebraischen Zahlkörper” and in his proof of War-ring’s Problem. In the field of geometry he introduced strictly axiomatic concepts in “Die Grundlagen der Geometrie” (1899). His works on the theory of integral equations and on the calculus of variations strongly influenced modern analysis. H. also worked successfully on problems of theoretical physics, especially on kinetic gas theory and relativity. As a consequence of the development of set theory and the problems arising in the foundations of mathematics, H. created his proof theory and thereby became one of the leaders of the axiomatic branch of the foundation of mathematics.Google Scholar
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