Alfred Bucherer

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Alfred Bucherer

Alfred Heinrich Bucherer (born July 9, 1863 in Cologne , † April 16, 1927 in Bonn ) was a German physicist who was best known for his experiments on relativistic mass . Bucherer was also the first to use the term “Einstein's theory of relativity” literally .

Training and work

Alfred Bucherer studied from 1884 to 1899 at the Leibniz University of Hanover , the Johns Hopkins University of Baltimore , the University of Strasbourg and the University of Leipzig . He completed his habilitation in 1899 at the Rheinische Friedrich-Wilhelms-Universität Bonn . Subsequently he taught physics and mathematics there until 1923.

In 1903 Alfred Bucherer published the first book to be published in German that dealt exclusively with the representation of vector calculation .

Like Henri Poincaré (1895 and 1900), Alfred Bucherer (1903b) also believed in the validity of the principle of relativity , i.e. all descriptions of electrodynamic effects may only contain relative movements of the body, not of the ether. However, he went one step further and deduced from this the non-existence of the ether . The theory that he developed based on this in 1906 also included the assumption that space has a geometry . However, his theory was formulated very vaguely, and in 1908 Walter Ritz was able to show that it also turned out to be contradictory. In contrast to Albert Einstein's theory of relativity , Alfred Bucherer did not draw any conclusions from the rejection of the aether with regard to the relativity of time. In 1906 Alfred Bucherer was the first to use the term “relativity theory” for Einstein's theory in a critical way, by changing Max Planck's term “relative theory” for the “Lorentz-Einstein theory”. In 1908, however, he soon rejected his own version of the principle of relativity and became a supporter of the “Lorentz-Einstein theory”.

His electron model , developed in 1904 , according to which the electron contracts in the direction of movement and expands perpendicular to it, was also of importance; independently of him, Paul Langevin had set up a very similar model in 1905. The "Bucherer-Langevin model" was an alternative:

  • on the electron model by Hendrik Antoon Lorentz (1899), Henri Poincaré (1905 and 1906) and Albert Einstein (1905), according to which the electron also contracts due to the length contraction, but does not expand perpendicular to it ,
  • and Max Abraham's model , according to which the electron is to be regarded as rigid.

All three models predicted that an electron's mass would increase the closer it gets to the speed of light . After the "Bucherer-Langevin model" was rejected relatively quickly, it was a matter of distinguishing between the Abrahamic and the Lorentz-Einsteinian formula. Particularly important in this context were Bucherer's experiments (1908), in which he repeated Walter Kaufmann's experiments on the velocity dependence of mass in an improved manner. While Kaufmann was the first (1901-1903) to show that mass varied with speed, he believed that the data from his more recent experiments (1905) tended to support Abraham's theory. Bucherer, on the other hand, believed that his own experiments had confirmed the Lorentz-Einstein model and thus the principle of relativity. Following this, Bucherer's measurements (which were repeated by Neumann in 1914, for example) were interpreted as confirmation of the special theory of relativity and relativistic mass and as a refutation of Abraham's theory in many presentations (however, this was immediately questioned by Adolf Bestelmeyer ). Much later (1938) it was found that the Kaufmann-Bucherer-Neumann experiments generally confirmed the velocity dependence of the mass, but were not accurate enough to distinguish between the various competing models. It was only in 1940 that this was achieved in favor of the theory of relativity.

Alfred Bucherer criticized (1923 and 1924) the general theory of relativity in some works . However, this criticism was rejected by Wenzl, who pointed to a misinterpretation of the principle of equivalence by Bucherer.

Honors

Publications

  • Addendum to: The effect of magnetism on the electromotive force . In: Annals of Physics . 295, No. 12, 1896, pp. 735-741. doi : 10.1002 / andp.18962951208 .
  • On the theory of the thermoelectricity of electrolytes . In: Annals of Physics . 308, No. 10, 1900, pp. 204-209. doi : 10.1002 / andp.19003081004 .
  • Elements of vector analysis with examples from theoretical physics . Teubner, Leipzig 1903.
  • Mathematical introduction to electron theory . Teubner, Leipzig 1904.
  • The deformed electron and the theory of electromagnetism . In: Physikalische Zeitschrift . 6, 1905, pp. 833-834.
  • An attempt to represent electromagnetism on the basis of relative movement . In: Physikalische Zeitschrift . 7, 1906, pp. 553-557.
  • On a new Principle of Relativity in Electromagnetism . In: Philosophical Magazine . 13, 1907, pp. 413-421.
  • The Action of Uniform Electric and Magnetic Fields on Moving Electrons . In: Philosophical Magazine . 13, 1907, p. 721.
  • On the Principle of Relativity and on the Electromagnetic Mass of the Electron. A Reply to Mr. Cunningham . In: Philosophical Magazine . 15, 1908, pp. 316-318.
  • The experimental confirmation of the principle of relativity . In: Annals of Physics . 333, No. 3, 1909, pp. 513-536. doi : 10.1002 / andp.19093330305 .
  • Addendum to my work: "Confirmation of the principle of relativity" . In: Annals of Physics . 334, No. 10, 1909, p. 1063. doi : 10.1002 / andp.19093341011 .
  • Answer to the criticism of Mr. E. Bestelmeyer regarding my experimental confirmation of the principle of relativity . In: Annals of Physics . 335, No. 15, 1909, pp. 974-986. doi : 10.1002 / andp.19093351506 .
  • The latest determinations of the specific charge of the electron . In: Annals of Physics . 342, No. 3, 1912, pp. 597-598. doi : 10.1002 / andp.19123420311 .
  • Correction to the work “The role of the location in the theory of relativity” . In: Annals of Physics . 379, No. 9, 1924, p. 104. doi : 10.1002 / andp.19243790906 .

literature

Individual evidence

  1. ^ MJ Crowe: A History of Vector Analysis: The Evolution of the Idea of ​​a Vectorial System . University of Notre Dame Press, Notre Dame 1967.
  2. ↑ Olivier Darrigol: Bucherer's theory . In: Electrodynamics from Ampère to Einstein . Clarendon Press, Oxford 2000, ISBN 0-19-850594-9 , pp. 369-372.
  3. ↑ Max Planck: The Kaufmann measurements of the deflectability of β-rays and their significance for the dynamics of electrons . In: Physikalische Zeitschrift . 7, 1906, pp. 753-761.
  4. ^ AI Miller: Albert Einstein's special theory of relativity. Emergence (1905) and early interpretation (1905-1911) . Addison-Wesley, Reading 1981, ISBN 0-201-04679-2 .
  5. ↑ M. Janssen, M. Mecklenburg: From classical to relativistic mechanics: Electromagnetic models of the electron . In: VF Hendricks et.al. (Ed.): Interactions: Mathematics, Physics and Philosophy . Springer, Dordrecht 2007, p. 65-134 .
  6. ↑ M. Wenzl: Against a misunderstanding of the equivalence hypothesis . In: Annals of Physics . tape 377 , 1923, pp. 457-460 .
  7. ↑ APS Fellow Archive. Retrieved February 9, 2020 .
  8. ^ Alfred-Bucherer-Strasse in the Bonn street cadastre

See also

Web links

Commons : Alfred Bucherer  - Collection of Images
Wikisource: Alfred Heinrich Bucherer  - Sources and full texts
personal data
SURNAME Bucherer, Alfred
ALTERNATIVE NAMES Bucherer, Alfred Heinrich (full name)
BRIEF DESCRIPTION German physicist
DATE OF BIRTH July 9, 1863
PLACE OF BIRTH Cologne
DATE OF DEATH April 16, 1927
Place of death Bonn