George Szekeres
George Szekeres , born György Szekeres (born May 29, 1911 in Budapest , † August 28, 2005 in Adelaide ) was a Hungarian-Australian mathematician who dealt with combinatorics .
Life
Szekeres studied chemistry at the Technical University of Budapest and then worked for six years as a chemical analyst in Budapest. In 1937 he married the mathematician Esther Klein . Szekeres showed mathematical talent even at school. In Hungary he had contact with Paul Turán and Paul Erdős , with whom he a. a. published from 1935. During the Second World War, the family evaded persecution as Jews in Shanghai (from 1939). In 1948, because of his publications, he was offered a lectureship in mathematics at the University of Adelaide . In 1963 he became a professor at the University of New South Wales in Sydney , where he stayed until his retirement in 1975.
He is known for the "Happy Ending Theorem" proposed by his girlfriend and later wife Esther Klein in 1933: Given five points on the plane in general position (that is, no two are identical and not three on a straight line), then there are four points below that form the corners of a convex quadrilateral. At that time, Esther Klein gave evidence in the discussion. The theorem was then published in a generalized form in 1935 by Erdős and Szekeres ( A combinatorial problem in geometry. Compositio Mathematica Vol. 2, 1935, p. 463): A sufficiently large number of points in the plane (in general position) contains a convex one Polygon with corner points. A problem that is only partially solved is to find estimates of the minimum number of points to which the theorem applies. In the same work Erdős and Szekeres' theorem about monotonous subsequences was proved: Every sequence of real numbers with a minimum length of contains either a monotonically increasing sequence of length or a monotonically decreasing sequence of length .
In combinatorics, he also worked on graph theory and on partitions. He is also known for contributions to general relativity , the Kruskal-Szekeres coordinates in the Schwarzschild solution of the field equations. He had a keen interest in algorithms and computers since the early 1960s. In numerical analysis, he was particularly concerned with the evaluation of multidimensional integrals. In function theory , he examined fractional iteration in particular, whereby the -th iterates of a function for non-integer values are defined with the help of Schröder's or Abelian functional equation.
He received the Order of Australia in 2002. The Australian Mathematical Society has awarded him the George Szekeres Medal every two years since 2002 .
George and Esther Szekeres died half an hour apart on the same day, August 28, 2005.
Web links
- John J. O'Connor, Edmund F. Robertson : George Szekeres. In: MacTutor History of Mathematics archive .
- Erdős, Szekeres: A combinatorial problem in geometry. Compositio Mathematica 1935.
Individual evidence
- ^ On the singularities of a Riemannian Manifold , Pub. Math. Debrecen, Volume 7, 1960, p. 285, reprinted in George FR Ellis , Malcolm AH MacCallum, Andrzej Krasinski (Eds.) Golden Oldies in General Relativity. Hidden Gems , Springer Verlag 2013
- ^ Obituary , The Sydney Morning Herald
| personal data | |
|---|---|
| SURNAME | Szekeres, George |
| ALTERNATIVE NAMES | Szekeres, György |
| BRIEF DESCRIPTION | Hungarian-Australian mathematician |
| DATE OF BIRTH | May 29, 1911 |
| PLACE OF BIRTH | Budapest |
| DATE OF DEATH | August 28, 2005 |
| Place of death | Adelaide |