John Edensor Littlewood

John Edensor Littlewood
Born	(1885-06-09)9 June 1885 Rochester, Kent, England
Died	Cambridge, England
Residence	United Kingdom
Nationality	British
Fields	Mathematician
Institutions	University of Cambridge
Alma mater	University of Cambridge
Doctoral advisor	Ernest William Barnes
Doctoral students	A. O. L. Atkin Sarvadaman Chowla Harold Davenport Srinivasa Ramanujan Stanley Skewes Donald C. Spencer Albert Ingham
Known for	Mathematical analysis
Notable awards	Smith's Prize (1908) Royal Medal (1929) De Morgan Medal (1938) Sylvester Medal (1943) Copley Medal (1958) Senior Berwick Prize (1960)

John Edensor Littlewood (9 June 1885 – 6 September 1977) was a British mathematician, best known for his achievements in analysis, number theory, and differential equations.

Life

Littlewood was born in 1885 in Rochester in Kent. He was the son of Edward Thornton Littlewood and Sylvia Ackland. He lived in Wynberg in Cape Town from 1892 to 1900 where his father (a 9th wrangler) was a headmaster. His uncommon middle name was the maiden name of his great-great-grandmother Sarah Edensor, who married Thomas Littlewood. He attended St Paul's School in London for three years, where he was taught by F. S. Macaulay, now known for his contributions to ideal theory. He studied at Trinity College, Cambridge and was the Senior Wrangler in the Mathematical Tripos of 1905. He was elected a Fellow of Trinity College in 1908 and, apart from three years as Richardson Lecturer in the University of Manchester, the balance of his career was spent at the University of Cambridge. He was appointed Rouse Ball Professor of Mathematics in 1928, retiring in 1950. He was elected a Fellow of the Royal Society in 1916, awarded the Royal Medal in 1929, the Sylvester Medal in 1943 and the Copley Medal in 1958. He was president of the London Mathematical Society from 1941 to 1943, and was awarded the De Morgan Medal in 1938 and the Senior Berwick Prize in 1960.

Work

Most of Littlewood's work was in the field of mathematical analysis. He began research under the supervision of Ernest William Barnes, who suggested that he attempt to prove the Riemann hypothesis: Littlewood showed that if the Riemann hypothesis is true then the Prime Number Theorem follows and obtained the error term. This work won him his Trinity fellowship. However, the link between the Riemann hypothesis and the Prime Number Theorem had been known before in Continental Europe, and Littlewood wrote later in his book, A Mathematician's Miscellany that his rediscovery of the result did not shed a positive light on the isolated nature of British mathematics at the time.

He coined Littlewood's law, which states that individuals can expect "miracles" to happen to them, at the rate of about one per month.

He continued to write papers into his eighties, particularly in analytical areas of what would become the theory of dynamical systems.

Littlewood is also remembered for his book of reminiscences, A Mathematician's Miscellany (new edition published in 1986).

Among his own PhD students were Sarvadaman Chowla, Harold Davenport , Donald C. Spencer and Srinivasa Ramanujan. Spencer reported that in 1941 when he (Spencer) was about to get on the boat that would take him home to the United States, Littlewood reminded him: "n, n alpha, n beta!" (referring to Littlewood's conjecture).

Littlewood's collaborative work, carried out by correspondence, covered fields in Diophantine approximation and Waring's problem, in particular. In his other work, he collaborated with Raymond Paley on Littlewood–Paley theory in Fourier theory, and with Cyril Offord in combinatorial work on random sums, in developments that opened up fields that are still intensively studied.

He worked with Mary Cartwright on problems in differential equations arising out of early research on radar: their work foreshadowed the modern theory of dynamical systems. Littlewood's 4/3 inequality on bilinear forms was a forerunner of the later Grothendieck tensor norm theory.

With Hardy

Littlewood collaborated for many years with G. H. Hardy. Together they devised the first Hardy–Littlewood conjecture, a strong form of the twin prime conjecture, and the second Hardy–Littlewood conjecture.

In a 1947 lecture, the Danish mathematician Harald Bohr said, "To illustrate to what extent Hardy and Littlewood in the course of the years came to be considered as the leaders of recent English mathematical research, I may report what an excellent colleague once jokingly said: 'Nowadays, there are only three really great English mathematicians: Hardy, Littlewood, and Hardy–Littlewood.'"

There is a story (related in the Miscellany) that at a conference Littlewood met a German mathematician who said he was most interested to discover that Littlewood really existed, as he had always assumed that Littlewood was a name used by Hardy for lesser work which he did not want to put out under his own name; Littlewood apparently roared with laughter. There are versions of this story involving both Norbert Wiener and Edmund Landau, who, it is claimed, "so doubted the existence of Littlewood that he made a special trip to Great Britain to see the man with his own eyes".

See also

• Critical line theorem
• Hardy–Littlewood circle method
• Hardy–Littlewood zeta-function conjectures
• Littlewood's conjecture
• Littlewood polynomial
• Littlewood's three principles of real analysis
• Littlewood–Offord problem
• Littlewood's Tauberian theorem
• Hardy–Littlewood tauberian theorem
• Hardy–Littlewood maximal function
• Littlewood subordination theorem

Further reading

• Littlewood's Miscellany, edited by B. Bollobás, Cambridge University Press; 1986. ISBN 0-521-33702-X (alternative title for A Mathematician's Miscellany)

External links

• .
• John Edensor Littlewood at the Mathematics Genealogy Project
• Papers of Littlewood on Number Theory
• A Mathematicians Miscellany