**Advances in theoretical mathematics **

Professor Richard Rado, FRS, Emeritus Professor of Pure Mathematics in the University of Reading, who died on December 23 at the age of 83, made outstanding theoretical contributions to his subject over a period of more than 50 years.

Rado was particularly known for his work in combinatorics, the study of the different ways certain operations can be performed a subject vastly developed over the last three decades. His name is often associated with Ramsey's Theory but Rado's paper, *Studien Zur Kombinatorik*, which appeared in 1933 is nowadays seen as a landmark and precursor of many subsequent developments.

Many of these developments were expounded in *Combinatorial Set Theory: Partition Relations for Cardinals* which Rado co-authored with three others and published in 1984. The full range and influence of Rado's work is, however, very much wider. For his contributions to pure mathematics also included set theory, classical analysis, number theory, algebra, the geometry of convex sets and measure theory. He displayed a versatility few have achieved this century. Born in Berlin on April 26, 1906, he was educated at the Universities of Göttingen and Berlin, and was one of many academics who left Nazi Germany during the 1930s. He continued his research at Cambridge, was a lecturer there and at the University of Sheffield. In 1947 he was appointed Reader in Mathematics at King's College, London, before going in 1954 as Professor of Mathematics at Reading. He retired from the chair in 1971.

In 1978, some felt belatedly, Rado was elected a Fellow of the Royal Society "for his work in combinatorics, including abstract independence structures, transversal theory and extensions of Ramsey's Theory (the partition calculus)". Perhaps the tribute which provided the most moving experience of his life, however, was his visit to the Free University of Berlin in October 1981 to lecture and receive an honorary doctorate.

The London Mathematical Society, on whose council he had served from 1948 to 1957 and of which he was successively secretary and vice-president, awarded him the senior Berwick Prize in 1972 for his work on partition relations. Royalties received from *Studies in Mathematics* (ed. L Mirsky, 1971), the Festschrift presented to him on his 65th birthday, went to endow the Richard Rado Prize at Reading University.

His health suffered after a road accident in 1983 and so in that year he ended his chairmanship of the British Combinatorial Committee, which he had founded in 1977.

He is survived by his wife, Luise, and one son.

Copyright (C) The Times, 1990