Philipp Lenard

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Philipp Lenard (around 1905)

Philipp Eduard Anton von Lenard (born June 7, 1862 in Preßburg , † May 20, 1947 in Messelhausen ) was an Austro-Hungarian , German physicist from 1907 . For his work on cathode rays and the development of electron theory, he was awarded the Nobel Prize in Physics in 1905 . From 1907 director of the Institute for Physics and Radiology at the Ruprecht-Karls-Universität Heidelberg , he became a propagandist of nationalism and anti-Semitism during the First World War and in the fight against the revolution in physics by Albert Einstein . From 1924 he publicly stood up for the leaders of the Hitler coup and the NSDAP . With the thesis: "Science is like everything what people produce, racially , by blood due", he became the spokesman of a " German physics ".

Life

Earlier career

Lenard was born in Pressburg in 1862 as the son of a Tyrolean wine merchant . The family was granted the hereditary title of nobility in 1722, but the descendants no longer used it from the end of the 19th century. Philipp Lenard attended the Royal Hungarian High School in Pressburg, where he was taught in Hungarian. In his youth, Lenard was a Hungarian nationalist. His preferred language was Hungarian, and he vehemently refused to use the German geographical names for the predominantly Hungarian province in which he lived. He usually wrote his name as Fülöp Lenard or Lenardi. In 1880 he studied science for two semesters in Budapest and Vienna , but then preferred to work in his father's wine shop in Pressburg. In 1883 he continued his studies in Heidelberg with Georg Hermann Quincke and Robert Bunsen . After a semester of study with Hermann von Helmholtz in Berlin , he finally received his doctorate in Heidelberg in 1886 with Georg Quincke with a thesis “About the vibration of falling drops”. Then he was assistant to Quincke in the physics institute of the Ruprecht-Karls-Universität Heidelberg until 1889 , where he continued his investigations into phosphorescence . In the decades that followed, pioneering work was carried out on the lighting mechanisms of so-called Lenard phosphors .

Cathode rays

After brief stopovers in London and Wroclaw began in April 1891 as an assistant to Heinrich Hertz in Bonn to work, where he in 1892 with his work, about the electricity of the waterfalls habilitated . In the following years he devoted numerous publications to waterfall electricity and thunderstorm electricity. After Hertz's early death in 1894, he published his collected works, including the well-known “Principles of Mechanics”. In Bonn Lenard also dealt with cathode rays , in particular with their passage through thin metal layers. Lenard wrote about it a widely acclaimed treatise "About cathode rays in gases of atmospheric pressure and in the extreme vacuum", which he submitted in 1893 and which appeared in 1894 in Poggendorf's Annalen der Physik. On the advice of Hertz, he no longer used mica as the exit window of his tube , but aluminum foil, which was, however, 8 times as thick as normal. He examined almost all materials that the laboratory showed for their behavior under the influence of the emerging radiation. Particularly noteworthy are his observations under Paragraph 9 “Cathode rays are photographically effective”, in which he described that even darkened photographic layers were blackened by these rays and objects brought into the beam were shown on the photo plate. The magnetic deflectability of the rays is also described, as is the fact that these rays could not be generated in completely evacuated tubes. A residual pressure is required, which was later confirmed with the operation of X-ray tubes . With the development of the discharge tube named after him in 1892 and the " Lenard window ", the possibility arose for the first time of examining cathode rays independently of the discharge process. His experiments helped to clarify the corpuscular nature of the cathode rays, with the priority of the discovery of the electron to his bitterness in 1897 with Joseph John Thomson . He also procured a discharge tube and a Lenard window for Conrad Röntgen from his own inventory, which were indispensable for the discovery of X-rays in 1895. After Röntgen became famous for discovering X-rays, Lenard accused him of robbing him of the discovery.
The argument about it smoldered for decades and flared up again at the end of the 1930s. E. Brüche and A. Recknagel, as editors of die electron devices , which gave the Lenard tube adequate space next to the X-ray tube, felt compelled to make comments: “Nevertheless, we want the fundamental relationship between Lenard and X-ray tubes by treating both devices together and underlining take uniform viewpoints into account, without wishing to interfere in the dispute that unfortunately recently took place over Röntgen's great discovery ”(p. 189). But also: "[...] In this regard, the X-ray tube could be viewed as a special case of the Lenard tube." (P. 190)

Photoelectric effect

After further stops in Breslau , Aachen and Heidelberg, he became a full professor at the Christian Albrechts University in Kiel in 1898 . Here for the first time he had unlimited experimental work opportunities. In 1900 he continued the investigations of the photoelectric effect by Heinrich Hertz (1886) and Wilhelm Hallwachs (1887 Hallwax effect ) and discovered the fundamental laws in the same year: With increasing light intensity, the number of electrons increases, but not their energy, which is exclusively depends on the frequency of the incident light. However, it was only Albert Einstein who succeeded in interpreting it in 1905 using the light quantum hypothesis .

Atomic model

From measurements of the absorption of cathode rays he developed his “ dynamide model ” of the atom in 1903 , according to which the atom ultimately had to be weightless and the centers of activity were only concentrated in a fraction of the space. With this, Lenard broke for the first time with the idea of ​​the atom as a massive structure and provided an important forerunner of the atomic model developed by Ernest Rutherford in 1910/1911 through scattering experiments with alpha particles .

Nobel Prize in Physics 1905

The years in Kiel were the most productive and creative in Lenard's life. In 1905 Lenard received the Nobel Prize in Physics for his work on cathode rays . He also dealt with the ionization of air by ultraviolet light (Lenard effect), the basis of which was his earlier work on waterfall and thunderstorm electricity, as well as arc and metal spectra and meteorological topics.

Radiological Institute Heidelberg

In 1907, after a long, serious illness, he succeeded his teacher Quincke in Heidelberg as professor of physics and director of the physical institute. In 1913 he set up the Radiological Institute, one of the most modern and largest physical institutes in Germany at the time; he headed it until his retirement in 1932. In Heidelberg, however, the focus of his scientific activities increasingly shifted from experimental research to the creation of summarizing representations. In the war years 1914–1918 he wrote numerous articles for the Handbuch der Physik .

Much of his anti-Semitic credentials arose during his tenure in Heidelberg.

Lenard and German Physics

End of research

Under the influence of World War I , the Treaty of Versailles and the Weimar Republic , the staunch monarchist, who signed the Manifesto of 93 in September 1914 , increasingly turned to anti-Semitic views. The theory of relativity and the quantum mechanics he did not understand. He rejected them as abstract and unrealistic. However, due to a widespread anti-relativism discussion, he was not alone in this stance. Lenard worked on an ether theory that the Michelson-Morley experiment or the perihelion of Mercury, which were then interpreted with the help of the theory of relativity, tried to interpret in the context of classical physics. He also attacked Albert Einstein's person in newspaper articles and lectures with violent polemics . The highlight was the public debate with Einstein on September 23, 1920 about the general theory of relativity at the renowned conference of natural scientists and doctors in Bad Nauheim , the Nauheim Discussion. From then on Lenard referred to the general theory of relativity as "Jewish fraud". Lenard's Heidelberg student Emil Rupp , who received his doctorate summa cum laude in 1920, turned to the theory of relativity and completed his habilitation in 1926 with a work on canal rays written behind Lenard's back , which allegedly experimentally confirmed Einstein's theory of wave-particle dualism . In a letter to Wilhelm Wien in 1927, Lenard doubted that this experiment had even been carried out in his laboratory. Rupp was exposed as a forger in 1935.

Disregard for state mourning for Walther Rathenau

After the murder of Walther Rathenau on June 24, 1922 Lenard refused to obey the state mourning ordered by the state of Baden and the closure ordered by the rectorate of the university. At the Physics Institute he did not flag up mourning, ignored the public rest day and demonstratively held a seminar: Because of a dead Jew, the professor had said, he would not let his students go idle. When this became known in the city, an angry crowd protested in front of the institute on June 27th. She was attacked from inside the building with water from fire hoses. Among the demonstrators was also the Social Democrat Carlo Mierendorff , who, according to Zuckmayer, entered Lenard's institute with a group of workers and took the professor into protective custody. “The institute was closed according to the ordinance without any act of violence occurring, and the professor was released after a few hours. Apart from this brief suspension, nothing happened to him. "

A judicial charge of trespassing was brought against Mierendorff, and shortly before his doctorate he was threatened with eviction from the university. "In both cases he achieved an unconditional acquittal through his brilliant defense and the positive opinion of all liberal professors." Lenard, on the other hand, was suspended from duty by the minister responsible, Willy Hellpach . He responded with a request for dismissal. After interventions by colleagues and students, the suspension and resignation were withdrawn. In the same year Lenard lost all his fortune as a result of inflation , and his only son died. The scientific community was also disappointed when Albert Einstein was awarded the Nobel Prize for the quantum-theoretical interpretation of the photoelectric effect, to which Lenard himself had made an experimental contribution. However, Lenard enthusiastically accepted Hans FK Günther's “ Rassenkunde des Deutschen Volkes ” and turned to National Socialism .

Support of the NSDAP

With Adolf Hitler Lenard took the first time in a letter dated 27 September 1923 contact. In it he offered Hitler to mediate contacts with the Pan-German Association . This letter was passed on to Hitler by Johannes Stark .

Johannes Stark and Lenard were the first well-known scientists to publicly advocate the NSDAP . In their joint appeal "Hitlergeist und Wissenschaft", which appeared in the "Großdeutsche Zeitung" on May 8, 1924, they committed themselves to the party program of the NSDAP and to the leaders of the coup attempt of November 9, 1923 six months ago : Hitler, Erich Ludendorff and Ernst Pöhner .

In 1926 there was a personal meeting with Hitler in Heidelberg. In 1928 Lenard became a public sponsor of the ethnically -minded, anti-Semitic National Socialist Society for German Culture , which was re-established in 1931 as a fighting association for German culture and Lenard was one of its founding members. In 1929 Lenard became an honorary member of the Association of Völkischer Teachers . After his retirement in 1932, Lenard received numerous honors as a leading representative of physics in the National Socialist regime , including the eagle shield of the German Reich in 1933 . However, its influence decreased during World War II. In 1935 the Physics Institute at Heidelberg University was renamed the “Philipp Lenard Institute”. From 1933 to 1946 he was a member of the Senate of the Kaiser Wilhelm Society .

Lenard became a member of the Reich Institute for the History of New Germany , where he was active as a member of the so-called " Research Department Jewish Question ". Lenard did not join the NSDAP until 1937 and was honored with the Golden Party Badge . The co-ordinated Prussian Academy of Sciences , of which he was a corresponding member since 1909, made Lenard an honorary member in 1942. This award was revoked on June 30, 1946. In 1909 he was elected a full member of the Heidelberg Academy of Sciences , from which he left in 1934.

Initiator of "Aryan physics"

Philipp Lenard (1942)

In the years that followed, a group of around 30 physicists represented " German Physics " alongside him and Johannes Stark . They rejected parts of modern theoretical physics as "dogmatic-dialectical" production. In Lenard's view, knowledge of nature is racially conditioned, and the Aryan race has the best prerequisites for this. In the history of the natural sciences, Italy was widely considered to be the birthplace of modern physics. The clarity of the models was required, and the experiment should be at the center of physics. Theoretical considerations should be based "on solid ground in classical physics". Quantum theory was rejected by Lenard, but accepted by other representatives of "German Physics", while the theory of relativity developed by Albert Einstein was largely ignored. However, the Lorentz contraction was considered by some supporters of German physics as an explanation for the negative outcome of the Michelson experiment.

In 1936 Lenard's textbook German Physics appeared in four volumes . It only describes areas of classical physics and does not deal with relativity theory or quantum mechanics. Discoveries of modern physics are instead explained by the ether theory and an atomic model of Johannes Stark. In the foreword of his textbook is the following passage, which is understood as the informal program of German physics: “German physics?” One will ask. I could also have said Aryan physics or the physics of people of Nordic nature, the physics of the explorers of reality, the seekers of truth, the physics of those who founded natural research. [...] In reality, science, like everything that humans produce, is racial and blood-based. In contrast to Johannes Stark , he remained the intellectual part within the German Physics movement and hardly took part in political activities.

In 1936 Lenard was awarded the NSDAP Prize for Art and Science by Adolf Hitler .

In November 1940 there was a debate, now known as the “Munich Religious Discussion”, between representatives of German physics ( Rudolf Tomaschek , the experimental physicists Alfons Bühl, Ludwig Wesch and Wilhelm Müller ) and modern physics (including Carl Ramsauer , Georg Joos , Hans Kopfermann and Carl Friedrich von Weizsäcker ). In it, the representatives of German Physics should publicly acknowledge scientifically immovable facts of modern physics and stop political attacks against them. The written agreement stated the following:

  1. The theoretical physics with all the mathematical tools is a necessary part of the overall physics.
  2. The facts of experience summarized in the special theory of relativity are an integral part of physics. However, the certainty of applying the special theory of relativity is not so great that further checking is unnecessary.
  3. The four-dimensional representation of natural processes is a useful mathematical aid; but it does not mean the introduction of a new view of space and time.
  4. Any connection between the theory of relativity and general relativism is rejected.
  5. Quantum and wave mechanics is the only currently known tool for the quantitative recording of atomic processes. It is desirable to advance beyond the formalism and its interpretative rules to a deeper understanding of the atoms.

With this declaration, German physics lost its influence and was ultimately no longer relevant. Lenard himself did not see his ideas adequately represented and assessed the declaration as treason. The representatives of modern physics, on the other hand, could live with this list of things that are taken for granted.

In 1944 part of his physical institute was relocated to Messelhausen in Baden. Lenard's bond with the institute was so strong that he went along with it. In 1945 the Americans spared him denazification measures because of his old age . He died in Messelhausen in 1947. His estate is now in the Deutsches Museum in Munich.

Honors

Lenard was honored with awards from many academies. In 1896 he received the Rumford Medal of the Royal Society and Matteucci Medal of the Italian Society of Sciences. In 1897 the French Academy of Sciences awarded him the Prix La Caze and in 1932 he received the American Franklin Medal. He was the first recipient of the Prize for Art and Knowledge awarded by the NSDAP as a German substitute for the Nobel Prize in 1936. Streets that were named after him were later renamed. B. 1966 Lenardstrasse in the Munich settlement Alte Heide in Domagkstrasse, Philipp-Lenard-Strasse in Lemgo 2006 in James-Franck -Strasse , Philipp-Lenard-Gasse in Klagenfurt 2008 in Karl-Landsteiner- Strasse. In 2015, the city of Gatineau in the Canadian province of Quebec renamed a Rue Philipp Lenard to Rue Marie Curie. There is a street named after Lenard (Lenardova ulica) in Lenard's birthplace Pressburg (Bratislava) in the Petržalka district .

The lunar crater Lenard is named after him.

Fonts

  • Great Naturalists: A History of Natural Research in Biographies. JF Lehmanns Verlag , Munich 1929 (digitized 6th edition, 1943) .
  • German physics in four volumes. JF Lehmanns Verlag, Munich 1936–1937. (Several editions) (digitized 4th edition, 1944) .
  • Notional continental barrier. Rather , Munich 1940 (reprint of his brochure England and Germany at the Time of the Great War , which was published in 1914, for political reasons ).
  • Scientific papers from the years 1886–1932. 3 volumes. Hirzel, Leipzig 1942–44.
  • Scientific treatises. Volume 4. Edited and commented by Charlotte Schönbeck. GNT-Verlag, Diepholz / Berlin 2003, ISBN 3-928186-35-3 .

literature

  • Andreas Kleinert , Charlotte Schönbeck: Lenard and Einstein: Their correspondence and their relationship before the Nauheim discussion of 1920. In: Gesnerus . Volume 35, No. 3/4, 1973, pp. 318-333.
  • Ernst Brüche, Hugo Marx: The Philipp Lenard Case: Man and "Politician". In: Physical sheets . Volume 23, Issue 6, 1967, pp. 262-267.
  • Arne Schirrmacher: Philipp Lenard: memories of a natural scientist, memories of a natural scientist who experienced the German Empire, the rule of the Jews and Hitler. Critical annotated edition of the original typoscript from 1931/1943. Springer, Berlin 2010, ISBN 978-3-540-89047-8 .
  • Rudolf Tomaschek: Philipp Lenard: On his 80th birthday on June 7, 1942. In: Völkischer Beobachter . 6./7. June 1942, No. 157/158, p. 5.
  • Sören Flachowsky: Lenard Philipp . In: Wolfgang Benz (Hrsg.): Handbook of Antisemitism - Anti-Semitism in Past and Present. Volume 2/1, de Gruyter, Berlin 2009, ISBN 978-3-598-24072-0 , p. 468f. partly also available online p. 468 f. books.google last accessed on December 16, 2013.
  • Christian Peters, Arno Weckbecker: On the way to power. On the history of the Nazi movement in Heidelberg 1920–1934. Documents and analyzes . With a foreword by Hartmut Soell . Zeitsprung, Heidelberg 1983, ISBN 3-924085-00-5 .
  • Klaus Hentschel (Ed.): Physics and National Socialism. An Anthology of Primary Sources. Birkhäuser, Basel 1996, ISBN 978-3-7643-5312-4 . 2nd edition 2011. ( Further information on the book from the publisher )
  • Andreas Kleinert: From Pressburg to Heidelberg: Philipp Lenard and the difficulties of a biography . In: Peter Zigmann (Ed.): The biographical trace in the history of culture and science. Jena 2006, ISBN 978-3-938203-45-3 , pp. 195-203.

Web links

Commons : Philipp Lenard  - Collection of images, videos and audio files

Individual evidence

  1. ^ A b Philipp Lenard: German Physics in Four Volumes , Munich 1936, Vol. I, Foreword p. IX; at the same time u. a. also published in the magazine “Volk im Werden”, issue 7 from 1936, p. 414, special issue of the Heidelberg student body for the 550th university anniversary; completely reproduced in Joseph Braunbeck: The other physicist - The life of Felix Ehrenhaft , Technisches Museum Wien 2003, p. 66 f.
    "German Physics"? one will ask. - I could also have said Aryan physics or the physics of people of Nordic nature, the physics of the explorers of reality, the seekers of truth, the physics of those who founded natural research. - “Science is and will remain international!” You will want to object to me.
    But this is based on an error. In reality, like everything that humans create, science is racial, blood-based. A semblance of internationality can arise if the general validity of the events of natural science is wrongly inferred from a general origin or if it is overlooked that the peoples of different countries have provided science of the same or a related kind as the German people, this only for this reason and to the extent that they were or were also predominantly of Nordic racial mix.
  2. ↑ Ph. Lenard: About cathode rays in gases of atmospheric pressure and in an extreme vacuum ; Annals of Physics and Chemistry, Ed. G. u. E. Wiedemann, founded by Poggendorf, Vol. 51, Issue 2, pp. 225 - 267, Leipzig 1894, Vlg. Joh. Ambrosius Barth
  3. ↑ Peters / Weckbecker p. 61.
  4. ↑ E. Brüche, A. Recknagel: electron devices , Springer Vlg., 1941, pp. 188 ff.
  5. ↑ Jörg Willer: Didactics in the Third Reich using the example of physics. In: Medical historical messages. Journal for the history of science and specialist prose research. Volume 34, 2015, ISBN 978-3-86888-118-9 , pp. 105–121, here: p. 105.
  6. ↑ Philipp Lenard: About ethers and urethers. 2nd edition, with a warning to German naturalists. Leipzig 1922.
  7. ↑ Soren Flachowsky: Lenard Philipp . In: Wolfgang Benz (Hrsg.): Handbook of Antisemitism - Anti-Semitism in Past and Present. Volume 2/1, de Gruyter, Berlin 2009, ISBN 978-3-598-24072-0 , p. 468f.
  8. ^ Philipp Lenard to Wilhelm Wien, January 9, 1927, WN. (= Vienna estate?), In: van Dongen: Emil Rupp, Albert Einstein and the Canal Ray Experiments on Wave-Particle Duality: Scientific Fraud and Theoretical Bias. (PDF file; 1.07 MB), p. 38ff.
  9. ^ A b c Carl Zuckmayer: As if it were a piece by me , licensed edition for the Bertelsmann Group, Gütersloh, 1966, pp. 302–303
  10. ↑ Written grounds for the judgment in the disciplinary criminal case against Carl Mierendorff from Grossenhain for disrupting the morals and order of academic life, Heidelberg, August 13, 1923 (Heidelberg University Archives, B-8910 Mierendorff). Printed in: Peters / Weckbecker pp. 70–72.
  11. ↑ See also Wilhelm Güde, The proceedings before the Disciplinary Court of the University of Heidelberg against Carlo Mierendorff because of his involvement in the storming of the University's Physics Institute. In: Legal history and other tours. Festschrift for Detlev Fischer. Edited by Ulrich Falk, Markus Gehrlein, Gerhard Kreft and Markus Obert. Karlsruhe 2018, pp. 207-218.
  12. ^ Georg Franz-Willing: Putsch and period of prohibition of the Hitler movement, November 1923 - February 1925. KW Schütz-Verlag , Preußisch Oldendorf 1977, ISBN 3-87725-085-8 .
  13. ↑ a b c d Ernst Klee : The dictionary of persons on the Third Reich. Who was what before and after 1945 . 2nd updated edition. Fischer Taschenbuch Verlag, Frankfurt am Main 2005, ISBN 3-596-16048-0 , p. 366.
  14. ↑ Wolfgang U. Eckart , Volker Sellin , Eike Wolgast : The University of Heidelberg under National Socialism , here on Philipp Lenard: Charlotte Schönbeck: Physik, Springer Heidelberg Berlin 2006, pp. 1087–1151, ISBN 978-3-540-21442-7 .
  15. ^ Members of the HAdW since it was founded in 1909. Philipp Lenard. Heidelberg Academy of Sciences, accessed on June 23, 2016 .
  16. ^ Woldemar Voigt: Physical research and teaching in Germany during the last hundred years , speech on behalf of the Georg-August University at the university's annual celebration on June 5, 1912, Göttingen 1912.
  17. ↑ Grimsehl-Tomaschek: Textbook of Physics (Grimsehl's Textbook of Physics, revised by Rudolf Tomaschek), Volume II, Part 2: Materie und Äther , Leipzig / Berlin 1938, 8th edition, p. 229 ff.
  18. ↑ Grimsehl-Tomaschek: Textbook of Physics (Grimsehl's Textbook of Physics re-edited by Rudolf Tomaschek), Volume II, Part 2: Materie und Äther , Leipzig / Berlin 1938, 8th edition, p. 430.
  19. ↑ Arne Schirrmacher: Philipp Lenard: Memories of a natural scientist. Critical annotated edition of the original typescript from 1931/1943. 2010, p. 8.
  20. ↑ Jörg Willer: Didactics in the Third Reich using the example of physics. In: Medical historical messages. Journal for the history of science and specialist prose research. Volume 34, 2015 (2016), ISBN 978-3-86888-118-9 , pp. 105–121, here: p. 105.
  21. ↑ Jörg Willer: Didactics in the Third Reich using the example of physics. 2015 (2016), p. 108.
  22. ↑ Seefeld 1942–1943. Meeting Notes and Reports, Samuel A. Goudsmit Papers, Series IV, Box 25, Folder 12: Alsos Mission , online on the American Institute of Physics website , Niels Bohr Library & Archives.
personal data
SURNAME Lenard, Philipp
ALTERNATIVE NAMES Lenard, Philipp Eduard Anton von (full name)
BRIEF DESCRIPTION German physicist, Nobel Prize in Physics 1905
DATE OF BIRTH June 7, 1862
PLACE OF BIRTH Bratislava (Pressburg)
DATE OF DEATH May 20, 1947
Place of death Messelhausen