|
This timeline of quantum mechanics shows the key steps, precursors and contributors to the development of quantum mechanics, quantum field theories and quantum chemistry. ==19th century== *1859 – Kirchhoff introduces the concept of a blackbody and proves that its emission spectrum depends only on its temperature.〔 *1860–1900 – Ludwig Eduard Boltzmann, James Clerk Maxwell and others develop the theory of statistical mechanics. Boltzmann argues that entropy is a measure of disorder.〔 * 1877 – Boltzmann suggests that the energy levels of a physical system could be discrete based on statistical mechanics and mathematical arguments; also produces the first circle diagram representation, or atomic model of a molecule (such as an iodine gas molecule) in terms of the overlapping terms α and β, later (in 1928) called molecular orbitals, of the constituting atoms. * 1887 – Heinrich Hertz discovers the photoelectric effect, shown by Einstein in 1905 to involve ''quanta'' of light. * 1888 – Hertz demonstrates experimentally that electromagnetic waves exist, as predicted by Maxwell.〔 * 1888 – Johannes Rydberg modifies the Balmer formula to include all spectral series of lines for the hydrogen atom, producing the Rydberg formula which is employed later by Niels Bohr and others to verify Bohr's first quantum model of the atom. * 1895 – Wilhelm Conrad Röntgen discovers X-rays in experiments with electron beams in plasma.〔 * 1896 – Antoine Henri Becquerel accidentally discovers radioactivity while investigating the work of Wilhelm Conrad Röntgen; he finds that uranium salts emit radiation that resembled Röntgen's X-rays in their penetrating power. In one experiment, Becquerel wraps a sample of a phosphorescent substance, potassium uranyl sulfate, in photographic plates surrounded by very thick black paper in preparation for an experiment with bright sunlight; then, to his surprise, the photographic plates are already exposed before the experiment starts, showing a projected image of his sample.〔 * 1896 – Pieter Zeeman first observes the Zeeman splitting effect by passing the light emitted by hydrogen through a magnetic field. *1896–1897 Marie Curie (née Skłodowska, Becquerel's doctoral student) investigates uranium salt samples using a very sensitive electrometer device that was invented 15 years before by her husband and his brother Jacques Curie to measure electrical charge. She discovers that rays emitted by the uranium salt samples make the surrounding air electrically conductive, and measures the emitted rays' intensity. In April 1898, through a systematic search of substances, she finds that thorium compounds, like those of uranium, emitted "Becquerel rays", thus preceding the work of Frederick Soddy and Ernest Rutherford on the nuclear decay of thorium to radium by three years.〔(Marie Curie and the Science of Radioactivity: Research Breakthroughs (1897–1904) ). Aip.org. Retrieved on 2012-05-17.〕 * 1897 – Ivan Borgman demonstrates that X-rays and radioactive materials induce thermoluminescence. * 1899 to 1903 – Ernest Rutherford, 1st Baron, Lord Rutherford of Nelson, of Cambridge, OM, FRS: During the investigation of radioactivity he coins the terms alpha and beta rays in 1899 to describe the two distinct types of radiation emitted by thorium and uranium salts. Ernest Rutherford is joined at McGill University in 1900 by Frederick Soddy and together they discover nuclear transmutation when they find in 1902 that radioactive thorium is converting itself into radium through a process of nuclear decay and a gas (later found to be ); they report their interpretation of radioactivity in 1903. Sir Ernest Rutherford becomes known as the "father of nuclear physics": with his nuclear atom model of 1911 he leads the exploration of nuclear physics.〔(Ernest Rutherford, Baron Rutherford of Nelson, of Cambridge ). Encyclopædia Britannica on-line. Retrieved on 2012-05-17.〕 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「Timeline of quantum mechanics」の詳細全文を読む スポンサード リンク
|