Previous  (Chronologically)  Next  Biographies Index

Previous  (Alphabetically)  Next  Welcome page 
Sydney Chapman attended a school in Patricroft up to the age of 14 when he entered the Royal Technical Institute, Salford (now the University of Salford). Encouraged to sit the Lancashire Scholarship examinations to gain entry to Manchester University he was placed fifteenth, the bottom place for the award of a scholarship.
At the age of 16, Sydney entered the University of Manchester in 1904 and studied engineering in the department headed by Osborne Reynolds. In mathematics he was taught by Lamb, the professor of mathematics, and J E Littlewood who arrived from Cambridge in Chapman's final year at Manchester.
At Lamb's suggestion he tried for a scholarship to Trinity College, Cambridge and, being successful, entered Trinity in 1908. Cambridge stimulated his interest more than anything before and he met there Hardy, Whitehead and Russell.
Chapman was able to start research while still an undergraduate and he was unsure whether to go in the direction of pure or applied mathematics. His first work was on summable series and he wrote two papers on this topic, one of them a joint paper with Hardy. However Larmor suggested he look at problems in the kinetic theory of gasses and, despite not being very happy with the applied mathematics which Lamb had taught him, his interest turned in this direction.
After graduating from Cambridge in 1910 he worked at the Greenwich Observatory and continued to work there until the beginning of World War I. However he was not entirely happy with devoting himself to astronomy as is pointed out in [4]:
... he did not feel he was a good observer, and he did not want to subordinate all his other interests to astronomy, in particular, he wanted to complete the work he had begun on the kinetic theory of gases.Chapman's religious principles made him a pacifist so he was exempted from military service and returned to Cambridge. However he was made to feel very unhappy and unwelcome because of his pacifist views and he suffered depression for a number of years because of it.
However his research did not suffer and between 1915 and 1917 he completed a series of important papers on thermal diffusion and the fundamentals of gas dynamics. He developed systematic approximations to the Maxwell  Boltzmann formulation for the velocity distribution function for interacting particles under general force laws.
In 1919 he was appointed to a chair at Manchester to succeed Lamb. He was appointed to the chair of mathematics at Imperial College London in 1924 succeeding Whitehead. Long before the start of World War II Chapman had seen the dangers of the Nazi rise to power in Germany. His pacifist views had changed (with some considerable influence from Hitler) so that by the start of the war he was ready to undertake war work and he worked on military operational research and incendiary bomb problems.
He returned to his post in London in 1945 but was less happy than he had been so he readily accepted the offer of the Sedleian Chair of Natural Philosophy at Oxford in 1946. He retired in 1953 and began to visit many places in the world.
He had two main bases, the Geophysical Institute in Alaska and the High Altitude Observatory in Boulder, Colorado. His visits to other places included Michigan and Minnesota in the USA, Istanbul, Ibadan, Cairo, Prague, Tokyo and Russia.
Chapman's main area of research was the Earth's magnetic field and for his work in this area he was elected to the Royal Society in 1919, and awarded the Society's Copley Medal in 1966:
... in recognition of his theoretical contributions to terrestrial and interplanetary magnetism, the ionosphere and the aurora borealis.He had begun work on geomagnetism in 1913 and between then and 1915 had published three papers on the topic. These interpreted magnetic variations to a dynamo theory.
He also received the Adams Prize in 1929 and, in 1957, he was president of the Special Commission of the International Geophysical Year. In fact he played a major role in initiating and guiding the International Geophysical Year which has been the greatest international geophysics cooperation of the twentieth century.
Chapman, when asked shortly before his death which work he had undertaken since retiring he had found most interesting, replied that it was his work on thermal diffusion in highly ionised gases, his work on magnetic storms, his work on instability along magnetic neutral lines, and his work on noctilucent clouds.
His personal characteristics are described in [4] as follows:
Those who knew Chapman all testify to his kindness, persistence, simplicity and integrity. His kindliness was appreciated by successive generations of research students and junior colleagues, in times of difficulty one could always turn to him for helpful advice.References (5 books/articles)
References elsewhere in this archive:
Sydney Chapman was elected to the Royal Society of London in 1919. You can see a history of the Royal Society and a list of the members among the mathematicians in our archive.
He was awarded the Royal Medal of the Royal Society in 1934 and the Copley Medal in 1964. You can see a history of the Royal Medal and a list of the winners in our archive and a history of the Copley Medal and a list of the winners.
He was the Royal Society's Bakerian lecturer in 1931. You can see a history of the Bakerian Lectures and a list of the lecturers.
S Chapman was the London Mathematical Society President in 1929  1931. You can see a history of the LMS and a list of the presidents.
He was the winner of the London Mathematical Society De Morgan Medal in 1944. You can see a history of the LMS De Morgan Medal and a list of the winners.
There is a Crater Chapman on the moon. You can see a list of lunar features named after mathematicians.