User:Abt 12/Jordan german article translation
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Ernst Pascual Jordan (18 October, 1902 in Hannover – 31 July, 1980 in Hamburg) was a German theoretical physicist and politician.
From the middle of the 1920s Pascual Jordan was mainly engaged in the conceptual development and mathematical formulation of quantum mechanics. He also produced ground-laying contributions to quantum field theory.
[edit] Life
Pascual Jordan – the name derives from a Spanish ancestor who settled in Hannover after the Napoleonic wars – begain studying Mathematics, Physics, and Zoology at the Reformgymnasium in Hannover in 1921, and after 1923 at the Univ. Goettingen, where he was graduated in 1924. He was thereafter the student of Max Born, at the time the director of the department of theoretical physics, and his then assistant, Werner Heisenberg; their collaboration became more intense in the following years. The trio published their pioneering results in 1925 in essays known as the „Three-Man Work“ in On Quantum Mechanics I + II (this is is ambiguous to me). After receiving his Doctorate in 1926 on the thesis Toward A Theory of Quantum Radiation he became a post-doc at Hamburg and in 1929 an adjunct professor (??) at the Univ. Rostock. In 1933 Jordan became a member of the NSDAP and the SA. He had already publicized his aggressively nationalalistic and militaristic political outlook in the late 1920s. In 1935 he was given a chair in Theoretical Physics. He also worked in the realm of bio-physics, mostly in the effect of radiation on living cells and organisms.
Despite his nationalistic outlook, he rejected the so-called, „German Physics“ and notably praised the work of Jewish physicists in his pop-science book, Physics of the the 20th Century. Also, his membership in the Nazi party had no obvious advantages for his career during the Nazi years. In 1939 he began working as a meteorologist for the Luftwaffe, and then in a Naval physics lab. In 1944 he became a full professor at Univ. Berlin, succeeding Max von Laues.
After the end of WWII and Nazi reign, his political stance became an obstacle to his academic work. It was only after denazification in 1947 that he received, on the recommendation of Wolfgang Pauli, a visiting professorship in Hamburg, where he became a full professor in 1953 and emeritus in 1971. From 1957-1961, Jordan was a member of the Bundestag for the CDU. He notably voted against the so-called Goettingen 18 (including Born and Heisenberg) on the question of arming the recently re-militarized Federal Republic with atomic weapons. His denunciation of the political judgement of his scientific mentor Max Born led to a split between the two.
[edit] Scientific Work
Together with Max Born, in 1925 Jordan developed the novel ideas of Heisenberg concerning the consistent mathematical formalism of matrix mechanics; among other things, he completed the proofs that Born had laid out for exchange rules of quantum mechanics. Independent of Dirac he presented transformation theory and broke ground in quantum field theory (second quantification). In this formulation, he used a mathematical structure that is known as „Jordan Algebra.“
His attempts in the 30s and 40s to use quantum theory in the realm of biology proved in the end to be unsuccessful.
In the post-war period his focus was on General Relativity (outlawed under the Nazis) and related themes (cosmology, gravitational physics). He contributed greatly to the re-establishment of these as a field of high-level research in Germany.
For his scientific achievements, Jordan was awarded the Max Planck Medal (1943) and the Gauss Medal (1955).
