Hans Geiger (physicist)

Johannes Geiger is a redirect to this article. For other people see Johann Geiger .

Hans Geiger (1928)

Johannes "Hans" Wilhelm Geiger (born September 30, 1882 in Neustadt an der Haardt ; †  September 24, 1945 in Potsdam ) was a German physicist . He became famous and named by him after he along with his doctoral Walther Müller developed Geiger counter (also Geiger-Müller counter called).

Life

Geiger counter, 1932. Science Museum London .

From 1902 Hans Geiger studied physics and mathematics in Erlangen , where he was a member of the Bubenreuth fraternity and in the first two semesters did his one-year military service on the side. In 1904 he also spent a semester at the Ludwig Maximilians University in Munich . In 1906 he passed his second state examination and received his doctorate in Erlangen under Eilhard Wiedemann with the work of radiation, temperature and potential measurements in discharge tubes with strong currents . After graduating, he became assistant to Arthur Schuster of Manchester and remained so from 1907 under his successor Ernest Rutherford , whose 1,911-positioned atomic model was partly based on Geiger's discoveries (see Rutherford scattering ). In addition to Rutherford, he also worked with Ernest Marsden, among others . At the end of his time in Manchester in 1912, Geiger was considered an international authority for measurements of radioactivity, which was also reflected in a book with Wilhelm Makower.

In 1912 Geiger went back to Germany to the Physikalisch-Technische Reichsanstalt in Berlin -Charlottenburg, where he set up a laboratory for radioactivity and worked with James Chadwick , who had followed him from Manchester and whom he also supported during his internment during the First World War , as well as with Walther Bothe . During the First World War he served as an artillery officer and worked in Fritz Haber's gas troops (the 35th Pioneer Regiment ) for the gas war. After completing his habilitation in Berlin in 1924, Geiger switched to the Christian Albrechts University in Kiel in 1925 as a professor . From 1924 to 1925 he and Bothe introduced the method of coincidence measurement , which they used to study the Compton effect . For this experiment, Bothe later received the Nobel Prize - after Geiger's death. Among other things, with their experiment they also showed the validity of the conservation laws of energy and momentum at the atomic level, which was at times doubted (by Niels Bohr among others ). Together with his doctoral student Walther Müller, he developed the Geiger-Müller counter tube in Kiel in 1928 (commonly known as the "Geiger counter"), which was presented to the public in 1929.

In 1929 Geiger moved to the Eberhard Karls University in Tübingen and finally became director of the Physics Institute at the Technical University of Berlin in 1936 as the successor to Gustav Hertz, who had been forced out of office by the National Socialists . There he dealt in particular with cosmic rays .

Karl Scheel and Hans Geiger (1928)

Geiger was founding editor of the Zeitschrift für Physik with Karl Scheel in 1920 and was one of the editors until 1945. After Scheel's death, he was editor-in-chief from 1936. In 1926 he was editor of the handbook of physics in Springer Verlag.

In 1939 he took part in the founding meetings of the Uranium Association and his advice to intensify research into nuclear energy was of decisive importance at their meeting in September. At the meeting of the Reich Research Council in 1942 on further support for nuclear energy research, he spoke out against further continuation of the work.

Hans Geiger died on September 24, 1945, shortly after his house in Potsdam had been vacated (it was in the restricted area of ​​the conference of the victorious allied powers in Potsdam) in a hospital. He had already retired from his scientific posts in 1942 due to a serious rheumatic disease.

Hans Geiger was buried in the New Cemetery in Potsdam . His grave has been preserved. The family who moved to West Berlin had a second tombstone erected in the Grunewald cemetery , which has also been preserved.

In 1929 he received the Hughes Medal of the Royal Society , in 1937 the Duddell Medal of the London Physical Society and in 1934 the Arrhenius Prize of the Academic Publishing Association Leipzig. Since 1932 he was a corresponding member of the Saxon Academy of Sciences and since 1936 a member of the Prussian Academy of Sciences . From 1936 he was a member of the board of the German Physical Society . In 1935 he was elected a member of the Leopoldina and in 1937 a corresponding member of the Göttingen Academy of Sciences .

One of his doctoral students is Otto Haxel , who was also his assistant at the TH Berlin.

A moon crater was named after him in 1970 and the asteroid (14413) Geiger in 2000 . The Hans-Geiger-Gymnasium in Kiel-Ellerbek and a lecture hall of the physics center of the Christian Albrechts University in Kiel are also named after him, as well as a primary school and a street in his birthplace Neustadt; in other cities new roads are named after him.

Familiar

Hans Geiger was the son of the grammar school teacher and later professor for Indology and Iranian Studies Wilhelm Geiger and the brother of the climatologist Rudolf Geiger . Geiger was married to Elisabeth Heffter, daughter of the Berlin pharmacologist Arthur Heffter , and had three sons: Jürgen, Klaus and Roland.

politics

Until his death in 1945, Geiger never spoke publicly for or against the Nazis. He was not a friend of German physics and was rejected by Philipp Lenard in 1927 as an "Anglophiler" as a successor to his chair. Wolff writes that Geiger together with Max Wien and Werner Heisenberg with a memorandum, quote: "[...] opposed German physics [...]".

There are also indications that Hans Geiger stood up for colleagues and students who had problems because of the Nuremberg Laws . Lieselott Herforth , a student who took the diploma examination with Hans Geiger, comments: "... he also took my college friend, who as a" half-Jewish "was only allowed to be registered as a listener (only because her father was a doctor during the First World War) , as a graduate student. And that in 1939/40! As an external student, she was able to take the diploma examination with me in 1940. " Ernst Stuhlinger remarks: “It was only much later that it became known that Professor Geiger helped some of his unfortunate colleagues who were forced to emigrate to establish a new existence abroad through his close and very friendly relations with Lord Rutherford and other influential Englishmen has " . After the war ended, Soviet soldiers confiscated Geiger's house in Potsdam . Swinne comments on this fact: "In June 1945 Geiger's house was confiscated and sealed off because the Potsdam Conference was being held nearby."

But Geiger did not always advocate the interests of colleagues. Hans Bethe , who was dismissed from civil service due to the Nuremberg Laws (his mother was Jewish) and who was currently in Tübingen for a professorship in theoretical physics, asked Geiger for his help, which Geiger refused. Bethe wrote to Sommerfeld “[...] in any case, when asked what was going to happen, I received the enclosed letter from Geiger, the brevity of which I actually find almost offensive and according to the wording I no longer believe that I would have to say many more words in Tübingen I have to talk. ”The exact content of the letter is not known. In an oral history interview with Charles Weiner in 1967, Bethe expressed her disappointment with Geiger's reaction, but without mentioning him by name.

Bunsentagung Münster 1932, Hans Geiger seated 2nd from the left, behind him his wife

Fonts (selection)

• with Walter Makower Practical measurements in radioactivity , Longmans, Green and Co., 1912 (French edition Gauthier-Villars 1919), German edition: Measurement methods in the field of radioactivity , Vieweg 1920
• Negative and positive rays , Springer 1927
• Editor of the Handbook of Physics, 24 vols., Springer 1926/27

literature

• Ewald Fünfer:  Geiger, Johannes Wilhelm. In: New German Biography (NDB). Volume 6, Duncker & Humblot, Berlin 1964, ISBN 3-428-00187-7 , p. 141 f. ( Digitized version ).
• Otto Haxel: Hans Geiger as a scientist and teacher . In: Lecture Notes in PhysicsVolume . Volume 178, 1983, pp. 1-9 ( doi: 10.1007 / 3-540-12001-7_241 ).
• Otto Haxel: Hans Geiger . In: Wilhelm Treue, Gerhard Hildebrandt (Ed.): Berlinische Lebensbilder. Natural scientist . Volume 1, Berlin 1987, ISBN 3767806975 , pp. 289-297.
• Edgar Swinne: Hans Geiger. Traces from a life for physics (= Berlin contributions to the history of natural sciences and technology . Volume 7). 2nd expanded edition, Sigma, Berlin 1991, ISBN 3928577050 .
• Peter Brix: Hans Geiger and the discovery of the atomic nucleus , Physics in Our Time 1982, No. 5
• Hans Geiger, “Mister Counter”. In: Kendall Haven, Donna Clark: 100 Most Popular Scientists for Young Adults: Biographical Sketches and Professional Paths , Libraries Unlimited, Englewood 1999, ISBN 978-1-56308-674-8 , pp. 211-215
• Thaddeus J. Trenn: Geiger, Hans (Johannes) Wilhelm . In: Charles Coulston Gillispie (Ed.): Dictionary of Scientific Biography . tape 5 : Emil Fischer - Gottlieb Haberlandt . Charles Scribner's Sons, New York 1972, p. 330-333 .

See also

• Geiger-Nuttall rule
• Geiger's range law

Web links

Commons : Hans Geiger  - collection of images, videos and audio files

• Literature by and about Hans Geiger in the catalog of the German National Library
• Biography in the commemorative publication 125 years of the Technical University of Berlin
• Klaus Wiesemann zu Geiger on the occasion of the naming of a lecture hall at the University of Kiel after Geiger in 2008 (PDF; 145 kB)

Individual evidence

1. ↑ Willy Nolte (Ed.): Burschenschafter Stammrolle. List of members of the German Burschenschaft according to the status of the summer semester 1934. Berlin 1934. P. 139.
2. ↑ Arne Schirrmacher: The Physics in the Great War , Physik Journal 13 (2014) No. 7, pp. 43–48.
3. ^ Karlsch: Hitler's bomb. DVA, 2005, p. 34.
4. ^ Karlsch: Hitler's bomb. DVA, 2005, p. 84.
5. ↑ Holger Krahnke: The members of the Academy of Sciences in Göttingen 1751-2001 (= Treatises of the Academy of Sciences in Göttingen, Philological-Historical Class. Volume 3, Vol. 246 = Treatises of the Academy of Sciences in Göttingen, Mathematical-Physical Class. Episode 3, vol. 50). Vandenhoeck & Ruprecht, Göttingen 2001, ISBN 3-525-82516-1 , p. 90.
6. ↑ Hans Geiger (physicist) in the IAU's Gazetteer of Planetary Nomenclature (WGPSN) / USGS
7. ↑ Minor Planet Circ. 41034
8. ↑ Alan D. Beyerchen : Science under Hitler. Kiepenheuer and Witsch, 1977, p. 141.
9. ^ ^{A b} Stefan L. Wolff: Expulsion and Emigration in Physics. In: Physics in Our Time. 24, No. 6, 1993, pp. 267–273, can also be found excerpts under displacement and emigration in physics .
10. ↑ Lieselott Herforth: Memories of my “graduate father” - Hans Geiger would have been 100 years old on September 30th. In: Spectrum. 13, issue 11, 1982, p. 29.
11. ↑ Ernst Stuhlinger: Hans Geiger in memory of 1882–1982. In: Building blocks for the history of the University of Tübingen , Volume 2, Tübingen 1984, p. 167.
12. ↑ Edgar Swinne: Hans Geiger - Traces from a life for physics. Berlin Contributions to the History of Natural Sciences and Technology, 2nd edition, 1991.
13. ↑ Bethe to Sommerfeld of April 11, 1933, SOM, printed in: M. Eckert et al., Privy Councilor Sommerfeld, exhibition catalog Deutsches Museum, pp. 141–144, Munich 1984; Transcription of an interview with Bethe on October 28, 1966, p. 92, AIP.
14. ↑ Bethe Oral History Interview, Niels Bohr Institute , literally said Bethe: Then I wrote a letter to the professor of experimental physics who had been very friendly to me and really had indicated that he liked my work and liked me to be there and so on , and I got back a very stiff letter that presumably the lectures in theoretical physics would have to be arranged differently the next term.