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Harold Davenport

Born	30 October 1907 Huncoat, Lancashire, England
Died	9 June 1969 Cambridge, England
Residence	UK
Nationality	English
Field	Mathematician
Institution	University of Wales University College London University of Cambridge
Alma mater	University of Manchester University of Cambridge
Academic advisor	J. E. Littlewood
Notable students	John Horton Conway Alan Baker
Known for	Number theory

Harold Davenport (30 October 1907 - 9 June 1969) was an English mathematician, known for his extensive work in number theory. He was born in Huncoat, Lancashire.

Contents 1 Early life 2 First steps in research 3 Later career 4 Influence 5 Books 6 Notes 7 References 8 External link

He was educated at Accrington Grammar School, the University of Manchester, where he graduated in 1927, and Trinity College, Cambridge. He became a research student of J. E. Littlewood, working on the question of the distribution of quadratic residues.

The attack on the distribution question leads quickly to problems that are now seen to be special cases of those on local zeta-functions, for the particular case of some special hyperelliptic curves such as

Y² = X(X − 1) (X − 2) ... (X − k).

Bounds for the zeroes of the local zeta-function immediately imply bounds for sums

Σ χ( x(x − 1) (x − 2) ... (x − k)).

where χ is the Legendre symbol modulo a prime number p, and the sum is taken over a complete set of residues mod p.

In the light of this connection it was appropriate that, with a Trinity research fellowship, Davenport in 1932–1933 spent time in Marburg and Göttingen working with Helmut Hasse, an expert on the algebraic theory. This produced the work on the Hasse-Davenport relations for Gauss sums, and contact with Hans Heilbronn, with whom Davenport would later collaborate. In fact, as Davenport later admitted, his inherent prejudices against algebraic methods ("what can you do with algebra?") probably limited the amount he learned, in particular in the 'new' algebraic geometry and Artin/Noether approach to abstract algebra.

He took an appointment at the University of Manchester in 1937, just at the time when Louis Mordell had recruited emigrés from continental Europe to build an outstanding department. He moved into the areas of diophantine approximation and geometry of numbers. These were fashionable, and complemented the technical expertise he had in the Hardy-Littlewood circle method; he was later, though, to let drop the comment that he wished he'd spent more time on the Riemann hypothesis.

He was President of the London Mathematical Society from 1957 to 1959.^[1] After professorial positions at the University of Wales and University College London, he was appointed to the Rouse Ball Chair of Mathematics in Cambridge in 1958. There he remained until his death, of lung cancer.

From about 1950 he was the obvious leader of a 'school', somewhat unusually in the context of British mathematics. If it was the successor to the school of mathematical analysis of G. H. Hardy and J. E. Littlewood, it was also more narrowly devoted to number theory, and indeed to its analytic side, as had flourished in the 1930s. This implied problem-solving, and hard-analysis methods. The outstanding works of Klaus Roth and Alan Baker exemplify what this can do, in diophantine approximation. Two reported sayings, "the problems are there", and "I don’t care how you get hold of the gadget, I just want to know how big or small it is", sum up the attitude, and could be transplanted today into any discussion of combinatorics.

Indeed, the whole approach was in firm opposition to Bourbaki, as understood anyway around 1960 across the English Channel. This amounted to a schism, based on lack of mutual comprehension, the consequences of which can be traced in detail, though the simplistic outlines are not so useful.

• The higher arithmetic (1952)
• Analytic methods for Diophantine equations and Diophantine inequalities (1962)
• Multiplicative number theory (1967)
• The collected works of Harold Davenport (1977) in four volumes, edited by B. J. Birch, H. Halberstam, C. A. Rogers

1. ^ P.R. Cooper. Presidents of the London Mathematical Society. Retrieved on February 22, 2007.

• C.A. Rogers, B.J. Birch, H. Halberstam, D.A. Burgess, "Harold Davenport. 1907-1969," Biographical Memoirs of Fellows of the Royal Society, Vol. 17, 1971, pp. 159-192.

• O'Connor, John J., and Edmund F. Robertson. "Harold Davenport". MacTutor History of Mathematics archive.