Arthur Erich Haas (April 30, 1884, in

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– February 20, 1941, in

Chicago Chicago is the List of municipalities in Illinois, most populous city in the U.S. state of Illinois and in the Midwestern United States. With a population of 2,746,388, as of the 2020 United States census, 2020 census, it is the List of Unite ...

) was an

Austria Austria, formally the Republic of Austria, is a landlocked country in Central Europe, lying in the Eastern Alps. It is a federation of nine Federal states of Austria, states, of which the capital Vienna is the List of largest cities in Aust ...

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate cau ...

, noted for a 1910 paper he submitted in support of his

habilitation Habilitation is the highest university degree, or the procedure by which it is achieved, in Germany, France, Italy, Poland and some other European and non-English-speaking countries. The candidate fulfills a university's set criteria of excelle ...

as '' Privatdocent'' at the

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that outlined a treatment of the hydrogen atom involving quantization of electronic orbitals, thus anticipating the

Bohr model In atomic physics, the Bohr model or Rutherford–Bohr model was a model of the atom that incorporated some early quantum concepts. Developed from 1911 to 1918 by Niels Bohr and building on Ernest Rutherford's nuclear Rutherford model, model, i ...

(1913) by three years. Haas's paper, however, was initially rejected and even ridiculed. As noted in his autobiography, Haas recalls: "When I lectured to the Chemical-Physical Society of Vienna ... Lecher ... referred to the presentation during open discussion as a carnival joke" (the lecture was held during carnival time in Austria, February 1910). Soon thereafter, however, by September 1911 at a physical science convention in

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, former detractors of Haas's work acknowledged it with greater enthusiasm as noted in a footnote: "We do not know what caused change of mind in 1911 and can merely suggest the general trend of thinking at the time: 1910 saw the beginning of a universal shift of opinion of the quantum concept." The significance of Haas's work lay in the establishment of a relationship between the

Planck constant The Planck constant, or Planck's constant, denoted by h, is a fundamental physical constant of foundational importance in quantum mechanics: a photon's energy is equal to its frequency multiplied by the Planck constant, and the wavelength of a ...

and atomic dimensions, having been first to correctly estimate the magnitude of what is today known as the Bohr radius. From 1936 to his death he was professor at the

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Acceptance at the 1911 Solvay Conference

During the proceedings of the first Solvay Conference in 1911 at which Bohr's mentor, Rutherford was present.

Max Planck Max Karl Ernst Ludwig Planck (; ; 23 April 1858 – 4 October 1947) was a German Theoretical physics, theoretical physicist whose discovery of energy quantum, quanta won him the Nobel Prize in Physics in 1918. Planck made many substantial con ...

's lecture ended with this remark: "... atoms or electrons subject to the molecular bond would obey the laws of quantum theory."

Hendrik Lorentz Hendrik Antoon Lorentz ( ; ; 18 July 1853 – 4 February 1928) was a Dutch theoretical physicist who shared the 1902 Nobel Prize in Physics with Pieter Zeeman for their discovery and theoretical explanation of the Zeeman effect. He derive ...

in the discussion of Planck's lecture raised the question of the composition of the atom based on Thompson's model with a great portion of the discussion around the Quantum atom developed by Arthur Erich Haas. Lorentz explained that due to the dimension of the Planck constant, it defined the atom. Haas's model of the atom is mentioned seventeen times during the Proceedings of the Conference. Planck uses Haas's model in his speech, saying: "A. E. Haas, for example, takes as oscillator the uniform sphere of J. J. Thomson, within which an electron can oscillate around the center. The maximum energy for this oscillation, which is reached when the amplitude becomes equal to the radius of the sphere, must be equal to the quantum of energy ''e'' = ''hν''."Original Proceedings of the 1911 Solvay Conference published 1912. THÉORIE DU RAYONNEMENT ET LES QUANTA. RAPPORTS ET DISCUSSIONS DELA Réunion tenue à Bruxelles, du 30 octobre au 3 novembre 1911, Sous les Auspices dk M. E. SOLVAY. Publiés par MM. P. LANGEVIN et M. de BROGLIE. Translated from the French, p. 108.

Works

* . * ''Einführung in die theoretische Physik'' (2 volumes) 1
online
Leipzig: Veit, 1919; 2. Berlin: de Gruyter, 1921. English translation: . * . English translation: . * . English translation: . * . English translation: . * . Revised English translation: . * . * . * (popular scientific).

References

External links

Arthur Erich Haas - FREE Arthur Erich Haas Biography , Encyclopedia.com: Facts, Pictures, Information!
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at the '' aeiou Encyclopedia'' {{DEFAULTSORT:Haas, Arthur Erich 1884 births 1941 deaths Austrian physicists University of Notre Dame faculty Fellows of the American Physical Society

Acceptance at the 1911 Solvay Conference

Works

See also

References

External links