Joseph L. Walsh | |
|---|---|
 | |
| Born | September 21, 1895 |
| Died | December 6, 1973 (aged 78) |
| Nationality | American |
| Alma mater | Harvard University |
| Known for | Walsh function Walsh code Walsh matrix Walsh–Lebesgue theorem |
| Scientific career | |
| Fields | Mathematics |
| Institutions | Harvard University |
| Doctoral advisor | Maxime Bôcher George David Birkhoff |
| Doctoral students | Joseph Leo Doob Orin J. Farrell Maurice Heins Donald J. Newman Theodore J. Rivlin Edward B. Saff Richard S. Varga |
Joseph Leonard Walsh (September 21, 1895 – December 6, 1973) was an American mathematician who worked mainly in the field of analysis. The Walsh function and the Walsh–Hadamard code are named after him. The Grace–Walsh–Szegő coincidence theorem is important in the study of the location of the zeros of multivariate polynomials.[1][2]
He became a member of the National Academy of Sciences in 1936 and served 1949–51 as president of the American Mathematical Society. Altogether he published 279 articles (research and others) and seven books, and advised 31 PhD students.
For most of his professional career he studied and worked at Harvard University. He received a B.S. in 1916 and a PhD in 1920. The Advisor of his PhD was Maxime Bôcher. Walsh started to work as lecturer in Harvard afterwards and became a full professor in 1935. He was an Invited Speaker of the ICM in 1920 at Strasbourg.[3] With two different scholarships he was able to study in Paris under Paul Montel (1920–21) and in Munich under Constantin Carathéodory (1925–26). From 1937 to 1942 he served as chairman of his department at Harvard. During World War II he served as an officer in the US navy and was promoted to captain right after end of the war. After his retirement from Harvard in 1966 he accepted a position at the University of Maryland where he continued to work up to a few months before his death.
- ^ Brändén, Petter; Wagner, David G. (18 Sep 2008). "A Converse to the Grace–Walsh–Szegő Theorem". Mathematical Proceedings of the Cambridge Philosophical Society. 147 (2): 447. arXiv:0809.3225. Bibcode:2009MPCPS.147..447B. doi:10.1017/S0305004109002424. S2CID 16180254.
- ^ Van Vleck, E. B. (1929). "On the location of roots of polynomials and entire functions". Bull. Amer. Math. Soc. 35 (5): 643–683. doi:10.1090/s0002-9904-1929-04794-3. MR 1561789.
- ^ "On the location of the roots of the derivative of a polynomial by J. L. Walsh". Comptes rendus du Congrès international des mathématiciens tenu à Strasbourg du 22 au 30 Septembre 1920. ICM proceedings. University of Toronto Press. 1921. pp. 339–342.