Geitel Hans-Friedrich Wolfenbüttel GroßeSchule (2a)

Hans Friedrich Karl Geitel (16 July 1855 in

Braunschweig Braunschweig () or Brunswick ( , from Low German ''Brunswiek'' , Braunschweig dialect: ''Bronswiek'') is a city in Lower Saxony, Germany, north of the Harz Mountains at the farthest navigable point of the river Oker, which connects it to the Nor ...

– 15 August 1923 in

Wolfenbüttel Wolfenbüttel (; nds, Wulfenbüddel) is a town in Lower Saxony, Germany, the administrative capital of Wolfenbüttel District. It is best known as the location of the internationally renowned Herzog August Library and for having the largest c ...

) was a German physicist. He is credited with coining the phrase "atomic energy."

Biography

Through the relocation of his family, his father was a

forester A forester is a person who practises forestry, the science, art, and profession of managing forests. Foresters engage in a broad range of activities including ecological restoration and management of protected areas. Foresters manage forests to ...

, Hans Geitel came to

Blankenburg Blankenburg may refer to: Places * Blankenburg am Harz, a German town in the district of Harz, Saxony-Anhalt * Blankenburg Castle (Harz), the castle in Blankenburg am Harz (see above) * Bad Blankenburg, a German town in the Saalfeld-Rudolstadt dis ...

in 1861 and grew up in close proximity to

Julius Elster Julius Johann Phillipp Ludwig Elster (24 December 1854 in Blankenburg – 6 April 1920) was a teacher and physicist. Biography Elster and Hans Friedrich Geitel, the son of a Forester, Forstmeister who had moved to Bad Blankenburg, Blankenburg with ...

. He attended school and high school together with Elster. A lifelong friendship developed between the two of them, their interest in science became a shared field of activity. During their studies both spent two years in Heidelberg and Berlin. In 1879 Geitel got his teaching degree in Braunschweig and accepted a position as teacher at the then called Herzogliche Große Schule (translation: Ducal Great School) in

. In 1881 Geitel succeeded in getting Julius Elster to the school as well. There they intensified their joint researches. Karl Bergwitz (1875–1958), who continued their research, was one of their students there. In 1892 Geitel was elected a member of the

German Academy of Sciences Leopoldina The German National Academy of Sciences Leopoldina (german: Deutsche Akademie der Naturforscher Leopoldina – Nationale Akademie der Wissenschaften), short Leopoldina, is the national academy of Germany, and is located in Halle (Saale). Founded ...

Publications

Geitel and Elster published works on

meteorology Meteorology is a branch of the atmospheric sciences (which include atmospheric chemistry and physics) with a major focus on weather forecasting. The study of meteorology dates back millennia, though significant progress in meteorology did not ...

nuclear physics Nuclear physics is the field of physics that studies atomic nuclei and their constituents and interactions, in addition to the study of other forms of nuclear matter. Nuclear physics should not be confused with atomic physics, which studies the ...

, and the

photoelectric effect The photoelectric effect is the emission of electrons when electromagnetic radiation, such as light, hits a material. Electrons emitted in this manner are called photoelectrons. The phenomenon is studied in condensed matter physics, and solid st ...

s. Geitel recognized the law of

radioactive decay Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is consid ...

in 1899 and coined the term atomic energy. In 1893 he invented the

photocell Photodetectors, also called photosensors, are sensors of light or other electromagnetic radiation. There is a wide variety of photodetectors which may be classified by mechanism of detection, such as photoelectric or photochemical effects, or by ...

Journals

* Elster, Julius and Geitel, Hans: Experiments on Hyperphosphorescenz. addenda to the annals of Physics and Chemistry, 21:455, 1897. * Elster, Julius and Geitel, Hans: Via the influence of a magnetic field on the Becquerel rays caused by the conductivity of the air negotiations of the German Physical Society, 1:136-138 May, 1899. * Elster, Julius and Geitel, Hans: About Ozone formation of glowing platinum surfaces and Electrical conductivity of ozonized by phosphorus air. Annals of Physics and Chemistry, 275:321-331, in 1890. * Elster, Julius and Geitel, Hans: Experiments on Becquerel. Annals of Physics and Chemistry, 302:735-740, in 1898.

Awards

In 1899, Geitel was awarded an honorary doctorate at the

University of Göttingen The University of Göttingen, officially the Georg August University of Göttingen, (german: Georg-August-Universität Göttingen, known informally as Georgia Augusta) is a public research university in the city of Göttingen, Germany. Founded ...

. In 1915 he was, along with Elster, awarded an

honorary degree An honorary degree is an academic degree for which a university (or other degree-awarding institution) has waived all of the usual requirements. It is also known by the Latin phrases ''honoris causa'' ("for the sake of the honour") or ''ad hono ...

of the

Braunschweig University of Technology Braunschweig () or Brunswick ( , from Low German ''Brunswiek'' , Braunschweig dialect: ''Bronswiek'') is a city in Lower Saxony, Germany, north of the Harz Mountains at the farthest navigable point of the river Oker, which connects it to the No ...

References

;Literature * Rudolf G. A. Fricke: J. Elster & H. Geitel - ''Jugendfreunde, Gymnasiallehrer, Wissenschaftler aus Passion, Döring Druck, Brunswick, 1992. * Horst-Rüdiger Jarck, Günter Scheel (Eds.): ''Braunschweigisches Biographisches Lexikon. 19. und 20. Jahrhundert'' (''Brunswick Biographical Dictionary. 19th and 20th Century''), Hanover, 1996, pp. 203–204. * Martin Weiser: Geitel Hans. In: New German Biography (NDB). Volume 6, Duncker & Humblot, Berlin, 1964, , p 164 (digitized). {{DEFAULTSORT:Geitel, Hans Friedrich 1855 births 1923 deaths 20th-century German physicists Scientists from Braunschweig People from the Duchy of Brunswick 19th-century German physicists

Biography

Publications

Journals

Awards

See also

References