Person: Hasse, Helmut
Helmut Hasse did fundamental work in algebra and number theory. He is e.g. known for Hasse diagrams.
Mathematical Profile (Excerpt):
- Helmut studied for two years at the Fichte-Gymnasium in Berlin before volunteering for naval service during World War I.
- In the academic year 1917/18 Hasse was stationed at Kiel on his naval duties and he was able to attend the lectures of Otto Toeplitz.
- He was most influenced by Hecke despite the fact that Hecke left Göttingen to take up an appointment in Hamburg only a few months after Hasse arrived in Göttingen.
- It might be supposed that Hasse would have followed Hecke to Hamburg but he did not take this route, going to study under Hensel at Marburg in 1920.
- Hensel's work on ppp-adic numbers was to have a major influence on the direction of Hasse's research.
- In October 1920 Hasse discovered the 'local-global' principle which shows that a quadratic form that represents 0 non-trivially over the ppp-adic numbers for each prime ppp, and over the real numbers, represents 0 non-trivially over the rationals.
- The importance of this result, now known as the Hasse principle, is that both the representability of a number by a given form and whether two forms are equivalent can be decided using only local information.
- In 1922 Hasse was appointed a lecturer at the University of Kiel, then three years later he was appointed professor at Halle.
- During his time at Kiel, Hasse kept in close contact with the mathematicians at Hamburg including Artin, Hecke, Ostrowski and Schreier.
- At Halle Hasse obtained fundamental results on the structure of central simple algebras over local fields.
- In 1930 Hensel retired from Marburg and Hasse was appointed to fill his chair.
- The year 1933 was to be significant for all of Germany and for Hasse in particular.
- When Weyl resigned from his professorship in Göttingen, Hasse received an offer as his successor.
- At one point, Hasse hoped to increase his influence with the authorities and so he applied for membership in the Nazi Party.
- But one of Hasse's antecendents was a Jew and, therefore, membership was not granted.
- From 1939 until 1945 Hasse was on war leave from Göttingen and he returned to naval duty, working in Berlin on problems in ballistics.
- In May 1949, Hasse was appointed professor at the Humboldt University in East Berlin.
- In 1950 Hasse was appointed to Hamburg where he continued to teach until he retired in 1966.
- This reference to editorial work is made because Hasse was editor of Crelle's Journal for 50 years.
- Hasse was honoured by many organisations during his life.
Born 25 August 1898, Kassel, Germany. Died 26 December 1979, Ahrensburg (near Hamburg), Germany.
View full biography at MacTutor
Tags relevant for this person:
Origin Germany
Thank you to the contributors under CC BY-SA 4.0! 
- Github:
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- non-Github:
- @J-J-O'Connor
- @E-F-Robertson
References
Adapted from other CC BY-SA 4.0 Sources:
- O’Connor, John J; Robertson, Edmund F: MacTutor History of Mathematics Archive
