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| notable_students = Freeman Dyson | known_for = | prizes = | spouse = | signature = Hans Bethe (signature).jpg | footnotes = }} Hans Albrecht Bethe (; July 2, 1906 – March 6, 2005) was a German and American nuclear physicist who, in addition to making important contributions to astrophysics, quantum electrodynamics and solid-state physics, won the 1967 Nobel Prize in Physics for his work on the theory of stellar nucleosynthesis. For most of his career, Bethe was a professor at Cornell University.〔Available at www.JamesKeckCollectedWorks.org () are the class notes taken by one of his students at Cornell from the graduate courses on Nuclear Physics and on Applications of Quantum Mechanics he taught in the spring of 1947.〕 During World War II, he was head of the Theoretical Division at the secret Los Alamos laboratory which developed the first atomic bombs. There he played a key role in calculating the critical mass of the weapons and developing the theory behind the implosion method used in both the Trinity test and the "Fat Man" weapon dropped on Nagasaki in August 1945. After the war, Bethe also played an important role in the development of the hydrogen bomb, though he had originally joined the project with the hope of proving it could not be made. Bethe later campaigned with Albert Einstein and the Emergency Committee of Atomic Scientists against nuclear testing and the nuclear arms race. He helped persuade the Kennedy and Nixon administrations to sign, respectively, the 1963 Partial Nuclear Test Ban Treaty and 1972 Anti-Ballistic Missile Treaty (SALT I). His scientific research never ceased and he was publishing papers well into his nineties, making him one of the few scientists to have published at least one major paper in his field during every decade of his careerwhich, in Bethe's case, spanned nearly seventy years. Freeman Dyson, once one of his students, called him the "supreme problem-solver of the 20th century". == Early years == Bethe was born in Strasbourg, which was then part of Germany, on July 2, 1906, the only child of Anna (née Kuhn) and Albrecht Bethe, a ''privatdozent'' of physiology at the University of Strasbourg. Although his mother, the daughter of a professor at the University of Strasbourg, was Jewish, he was raised a Protestant like his father. Despite having a religious background, he was not religious in later life, and described himself as an atheist. His father accepted a position as professor and director of the Institute of Physiology at the University of Kiel in 1912, and the family moved into the director's apartment at the Institute. He was initially schooled privately by a professional teacher as part of a group of eight girls and boys. The family moved again in 1915 when his father became the head of the new Institute of Physiology at the University of Frankfurt am Main. Bethe attended the Goethe-Gymnasium in Frankfurt, Germany. His education was interrupted in 1916, when he contracted tuberculosis, and he was sent to Bad Kreuznach to recuperate. By 1917, he had recovered sufficiently to attend the local ''realschule'', and the following year he was sent to the ''Odenwaldschule'', a private, coeducational boarding school. He attended the ''Goethe-Gymnasium'' again for his final three years of secondary schooling, from 1922 to 1924. Having passed his ''abitur'', Bethe entered the University of Frankfurt in 1924. He decided to major in chemistry. The instruction in physics was poor, and while there were distinguished mathematicians in Frankfurt like Carl Ludwig Siegel and Otto Szász, Bethe disliked their approaches, which presented mathematics without reference to the other sciences. Bethe found that he was a poor experimentalist who destroyed his lab coat by spilling sulfuric acid on it, but he found the advanced physics taught by the associate professor, Walter Gerlach, more interesting. Gerlach left in 1925, and was replaced by Karl Meissner, who advised Bethe that he should go to a university with a better school of theoretical physics, specifically the University of Munich, where he could study under Arnold Sommerfeld. Bethe entered the University of Munich in April 1926, where Sommerfeld took him on as a student on Meissner's recommendation. Sommerfeld taught an advanced course on differential equations in physics, which Bethe enjoyed. Because he was such a renowned scholar, Sommerfeld frequently received advance copies of scientific papers, which he put up for discussion at weekly evening seminars. When Bethe arrived, Sommerfeld had just received Erwin Schrödinger's papers on wave mechanics. For his PhD thesis, Sommerfeld suggested that Bethe examine electron diffraction in crystals. As a starting point, Sommerfeld suggested Paul Ewald's 1914 paper on X-ray diffraction in crystals. Bethe later recalled that he became too ambitious, and, in pursuit of greater accuracy, his calculations became unnecessarily complicated. When he met Wolfgang Pauli for the first time, Pauli told him: "After Sommerfeld's tales about you, I had expected much better from you than your thesis." "I guess from Pauli," Bethe later recalled, "that was a compliment." 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Hans Bethe」の詳細全文を読む スポンサード リンク
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