George Szekeres

George Szekeres (* May 29, 1911 in Budapest, † August 28 2005 in Adelaide ) was a Hungarian- Australian mathematician who worked on combinatorics.

Life and work

Szekeres studied chemistry at the Technical University of Budapest and then worked six years as a chemical analyst in Budapest. In 1937 he married the mathematician Esther Klein. Szekeres showed already at the school talent in mathematics and was in Hungary in contact with Paul Erdős and Paul Turán and published in 1935, inter alia, with Erdős. During the Second World War, the family gave way before the persecution as a Jew ( from 1939 ) to Shanghai from. In 1948 he was offered because of its publications 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 remained until his retirement in 1975.

He is best known for the " Happy Ending Theorem", which suggested his then girlfriend and future wife, Esther Klein, 1933: Given five points in the plane in general position (that is, no two are identical, and not three in a straight line ), then there are four of points that form the vertices of a convex quadrilateral. Esther Klein was then under discussion a proof. The rate then was published in generalized form in 1935 by Erdős and Szekeres (A combinatorial problem- in Compositio Mathematica geometry Vol.2, 1935, S.463. ): Contains a sufficient number of points in the plane ( in general position ) is a convex polygon with vertices. As a partially unsolved problem is to find estimates for the minimum number of points which have satisfied the sentence. In the same paper, the set of Erdős and Szekeres on monotone subsequences was proved: Every sequence of real numbers with a minimum length of either contains a monotonically increasing sequence of length or a monotonically decreasing sequence of length.

In combinatorics, he also worked in graph theory and partitions. He is also known for his contributions to general relativity, the Kruskal- Szekeres coordinates in the Schwarzschild solution of the field equations. He had a strong interest in algorithms and computers since the early 1960s. In the numerical analysis, he has been dealing with the evaluation of multidimensional integrals. In the theory of functions he examined in particular fractional iteration, where the- th iterate of a function for non-integer can be defined with the help of Schröder 's or Abel's functional equation.

He received the 2002 Order of Australia.

George and Esther Szekeres died at a distance of half an hour on the same day, August 28, 2005.

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