Sydney Chapman (mathematician)

Sydney Chapman FRS (29 January 1888 – 16 June 1970Obituary, The Times [http://www-history.mcs.st-andrews.ac.uk/Obits/Chapman.html] ] T. G. Cowling, Sydney Chapman. 1888-1970, Biographical Memoirs of Fellows of the Royal Society, Vol. 17, (Nov., 1971), pp. 53-89 ] ) was a British mathematician and geophysicist.Cite journal
doi = 10.1007/BF00177026
volume = 11
issue = 5
pages = 599-606
last = Akasofu
first = Syun-I.
title = In memoriam Sydney Chapman
journal = Space Science Reviews
accessdate = 2008-09-07
date = 1970-12-01
url = http://dx.doi.org/10.1007/BF00177026]

Life

Chapman was born in Eccles, near Manchester in England. In 1904 at age 16, Chapman entered the Victoria University of Manchester initially studying engineering in the department headed by Osborne Reynolds. Chapman was taught mathematics by Horace Lamb, the Bayer professor of mathematics, and JE Littlewood, who came from Cambridge in Chapman's final year at Manchester. Although he graduated with an engineering degree, Chapman had become so enthusiastic for mathematics that he stayed for one further year to take a mathematics degree. Following Lamb's suggestion, Chapman applied for a scholarship to Trinity College, Cambridge. He was at first awarded only a partial scholarship as a sizar (meaning that he obtained financial support by acting as a servant other students), but from his second year onwards he received a full scholarship. He graduated as a wrangler in 1910. He began researching in pure mathematics under G. H. Hardy, but later that year was asked by Sir Frank Dyson to be his chief assistant at the Royal Greenwich Observatory. From 1914 to 1919 he returned to Cambridge as a lecturer in mathematics and a fellow of Trinity. He held the Beyer Chair of Applied Mathematics at the Manchester from 1919 to 1924, the same position held by Lamb, and then moved to Imperial College London. During the Second World War he was Deputy Scientific Advisor to the Army Council.

In 1946, Chapman was elected to the Sedleian Chair of Natural Philosophy at Oxford, and was appointed fellow of Queen's College. In 1953, on his retirement from Oxford, Chapman took research and teaching opportunities of different time durations all over the world, including at the University of Alaska and the University of Colorado, but also as far afield as in Istanbul, Cairo, Prague, and Tokyo.

Chapman died in Boulder, Colorado in 1970 at the age of 82.

Work

Chapman's most noted mathematical accomplishments were in the field of stochastic processes (random processes), especially Markov processes. In his study of Markovian stochastic processes and their generalizations, Chapman and the Russian Andrey Kolmogorov independently developed the pivotal set of equations in the field, the Chapman-Kolmogorov equations. Chapman is credited with working out, in 1930, the photochemical mechanisms that give rise to the ozone layerSydney Chapman, eighty: From His FriendsBy Sydney Chapman, Syun-Ichi Akasofu, Benson Fogle, Bernhard Haurwitz, University of Alaska (College). Geophysical Institute, National Center for Atmospheric Research (U.S.)Published by National Center for Atmospheric Research, 1968] .

Chapman is also recognized as one of the pioneers of solar-terrestial physics. This interest stemmed from his early work on the kinetic theory of gases. Chapman studied magnetic storms and aurorae, developing theories to explain their relation to the interaction of the Earth's magnetic field with the solar wind. Chapman was President of the Special Committee for the International Geophysical Year (IGY). The idea of the IGY stemmed from a discussion in 1950 between Chapman and scientists including James Van Allen. The IGY was held in 1957-58, and resulted in great progress in fields including Earth and space sciences, as well as leading to the first satellite launches.

Honours

Chapman was bestowed many honours over his career including the Smith Prize in 1913, election as a Fellow of the Royal Society in 1919. Royal Society Bakerian lecturer in 1931, Royal Society Royal Medal in 1934, London Mathematical Society De Morgan Medal in 1944. In 1949, he was awarded the Gold Medal of the Royal Astronomical Society and was elected as a Fellow of the Royal Society of Edinburgh in 1953. In 1964, he was awarded the Copley Medal of the Royal Society. In addition to the Royal Society and the Royal Society of Edinburgh, he was elected to National Academies of Science of the United States, Norway, Sweden and Finland. He served as President of the London Mathematical Society during 1929-1931.

The lunar Crater Chapman is named in his honour as is the Sydney Chapman Building on the campus of the University of Alaska Fairbanks (UAF). This building served as the first permanent home of UAF's Geophysical Institute.

ee also

* Chapman function
* Chapman-Kolmogorov equations
* Ozone layer

References

External links

*
* [http://www.aip.org/history/ead/19990060_content.html Finding aid to papers of Sydney Chapman] , Neils Bohr Library and Archives, accessed 07/09/2008
* [http://www.gi.alaska.edu/chapman/ Sydney Chapman page at the Geophysical Institute of the University of Alaska, Fairbanks] includes sections from "Sydney Chapman, Eighty, From His Friends", accessed 04 Oct 2008