Sydney Chapman (29 January 1888 – 16 June 1970)
was a British mathematician and
geophysicist
Geophysics () is a subject of natural science concerned with the physical processes and physical properties of the Earth and its surrounding space environment, and the use of quantitative methods for their analysis. The term ''geophysics'' som ...
.
His work on the
kinetic theory of gases
Kinetic (Ancient Greek: κίνησις “kinesis”, movement or to move) may refer to:
* Kinetic theory, describing a gas as particles in random motion
* Kinetic energy, the energy of an object that it possesses due to its motion
Art and ent ...
,
solar-terrestrial physics, and the
Earth
Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's sur ...
's
ozone layer
The ozone layer or ozone shield is a region of Earth's stratosphere that absorbs most of the Sun's ultraviolet radiation. It contains a high concentration of ozone (O3) in relation to other parts of the atmosphere, although still small in rel ...
has inspired a broad range of research over many decades.
Education and early life
Chapman was born in
Eccles, near
Salford
Salford () is a city and the largest settlement in the City of Salford metropolitan borough in Greater Manchester, England. In 2011, Salford had a population of 103,886. It is also the second and only other city in the metropolitan county afte ...
in England and began his advanced studies at a technical institute, now the
University of Salford
, caption = Coat of ArmsUniversity of Salford
, mottoeng = "Let us seek higher things"
, established = 1850 - Pendleton Mechanics Institute 1896 – Royal Technical Institute, Salford 1967 – gained ...
, in 1902. In 1904 at age 16, Chapman entered the
University of Manchester
The University of Manchester is a public university, public research university in Manchester, England. The main campus is south of Manchester city centre, Manchester City Centre on Wilmslow Road, Oxford Road. The university owns and operates majo ...
. He competed for a scholarship to the university offered by his home county, and was the last student selected. Chapman later reflected, "I sometimes wonder what would have happened if I'd hit one place lower."
[ He initially studied engineering in the department headed by Osborne Reynolds. Chapman was taught mathematics by Horace Lamb, the Beyer professor of mathematics, and J. E. 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
Trinity College is a constituent college of the University of Cambridge. Founded in 1546 by King Henry VIII, Trinity is one of the largest Cambridge colleges, with the largest financial endowment of any college at either Cambridge or Oxford. ...
. He was at first awarded only a partial scholarship as a sizar
At Trinity College, Dublin and the University of Cambridge, a sizar is an undergraduate who receives some form of assistance such as meals, lower fees or lodging during his or her period of study, in some cases in return for doing a defined jo ...
(meaning that he obtained financial support by acting as a servant to other students), but from his second year onwards he received a full scholarship. He graduated as a wrangler in 1910. He began his research in pure mathematics
Pure mathematics is the study of mathematical concepts independently of any application outside mathematics. These concepts may originate in real-world concerns, and the results obtained may later turn out to be useful for practical applications, ...
under G. H. Hardy, but later that year was asked by Sir Frank Dyson to be his chief assistant at the Royal Greenwich Observatory
The Royal Observatory, Greenwich (ROG; known as the Old Royal Observatory from 1957 to 1998, when the working Royal Greenwich Observatory, RGO, temporarily moved south from Greenwich to Herstmonceux) is an observatory situated on a hill in ...
.
Career and research
From 1914 to 1919, Chapman returned to Cambridge as a lecturer in mathematics and a fellow of Trinity. He held the Beyer Chair of Applied Mathematics
The Beyer Chair of Applied Mathematics is an endowed professorial position in the Department of Mathematics, University of Manchester, England. The endowment came from the will of the celebrated locomotive designer and founder of locomotive builde ...
at Manchester from 1919 to 1924, the same position as had been held by Lamb, and then moved to Imperial College London
Imperial College London (legally Imperial College of Science, Technology and Medicine) is a public research university in London, United Kingdom. Its history began with Prince Albert, consort of Queen Victoria, who developed his vision for a cu ...
. During the Second World War
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposi ...
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 The Queen's College, Oxford
The Queen's College is a constituent college of the University of Oxford, England. The college was founded in 1341 by Robert de Eglesfield in honour of Philippa of Hainault. It is distinguished by its predominantly neoclassical architecture, ...
. In 1953, on his retirement from Oxford, Chapman took research and teaching opportunities all over the world,[ including at the ]University of Alaska
The University of Alaska System is a system of public universities in the U.S. state of Alaska. It was created in 1917 and comprises three separately accredited universities on 19 campuses. The system serves nearly 30,000 full- and part-time stu ...
and the University of Colorado
The University of Colorado (CU) is a system of public universities in Colorado. It consists of four institutions: University of Colorado Boulder, University of Colorado Colorado Springs, University of Colorado Denver, and the University o ...
, but also as far afield as Istanbul
)
, postal_code_type = Postal code
, postal_code = 34000 to 34990
, area_code = +90 212 (European side) +90 216 (Asian side)
, registration_plate = 34
, blank_name_sec2 = GeoTLD
, blank_i ...
, Cairo
Cairo ( ; ar, القاهرة, al-Qāhirah, ) is the capital of Egypt and its largest city, home to 10 million people. It is also part of the largest urban agglomeration in Africa, the Arab world and the Middle East: The Greater Cairo metr ...
, Prague, and Tokyo. As the Advisory Scientific Director of the University of Alaska Geophysical Institute The Geophysical Institute of the University of Alaska Fairbanks conducts research into space physics and aeronomy; atmospheric sciences; snow, ice, and permafrost; seismology; volcanology; and tectonics and sedimentation. It was founded in 1946 b ...
from 1951 to 1970, he spent three months of the year in Alaska
Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U ...
, usually during winter for research into auroras. Much of the remainder of the year he spent at the High Altitude Observatory in Boulder, Colorado.[Sydney Chapman, eighty: From His Friends
By 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's most noted mathematical accomplishments were in the field of stochastic processes
In probability theory and related fields, a stochastic () or random process is a mathematical object usually defined as a family of random variables. Stochastic processes are widely used as mathematical models of systems and phenomena that ap ...
(random processes), especially Markov process
A Markov chain or Markov process is a stochastic model describing a sequence of possible events in which the probability of each event depends only on the state attained in the previous event. Informally, this may be thought of as, "What happen ...
es. In his study of Markovian stochastic processes and their generalizations, Chapman and the Russian Andrey Kolmogorov
Andrey Nikolaevich Kolmogorov ( rus, Андре́й Никола́евич Колмого́ров, p=ɐnˈdrʲej nʲɪkɐˈlajɪvʲɪtɕ kəlmɐˈɡorəf, a=Ru-Andrey Nikolaevich Kolmogorov.ogg, 25 April 1903 – 20 October 1987) was a Sovi ...
independently developed the pivotal set of equations in the field, the Chapman–Kolmogorov equation In mathematics, specifically in the theory of Markovian stochastic processes in probability theory, the Chapman–Kolmogorov equation(CKE) is an identity relating the joint probability distributions of different sets of coordinates on a stochastic ...
s. Chapman is credited with working out, in 1930, the photochemical mechanisms that give rise to the ozone layer
The ozone layer or ozone shield is a region of Earth's stratosphere that absorbs most of the Sun's ultraviolet radiation. It contains a high concentration of ozone (O3) in relation to other parts of the atmosphere, although still small in rel ...
.
Chapman is recognised as one of the pioneers of solar-terrestrial physics. This interest stemmed from his early work on the kinetic theory of gases. Chapman studied magnetic storms and aurorae
An aurora (plural: auroras or aurorae), also commonly known as the polar lights, is a natural light display in Earth's sky, predominantly seen in high-latitude regions (around the Arctic and Antarctic). Auroras display dynamic patterns of bri ...
, developing theories to explain their relation to the interaction of the Earth's magnetic field
Earth's magnetic field, also known as the geomagnetic field, is the magnetic field that extends from Earth's interior out into space, where it interacts with the solar wind, a stream of charged particles emanating from the Sun. The magneti ...
with the solar wind
The solar wind is a stream of charged particles released from the upper atmosphere of the Sun, called the corona. This plasma mostly consists of electrons, protons and alpha particles with kinetic energy between . The composition of the sol ...
. He disputed and ridiculed the work of Kristian Birkeland
Kristian Olaf Bernhard Birkeland (13 December 1867 – 15 June 1917) was a Norwegian scientist. He is best remembered for his theories of atmospheric electric currents that elucidated the nature of the aurora borealis. In order to fund his res ...
and Hannes Alfvén
Hannes Olof Gösta Alfvén (; 30 May 1908 – 2 April 1995) was a Swedish electrical engineer, plasma physicist and winner of the 1970 Nobel Prize in Physics for his work on magnetohydrodynamics (MHD). He described the class of MHD waves now ...
, later adopting Birkeland's theories as his own. Chapman and his first graduate student
Postgraduate or graduate education refers to academic or professional degrees, certificates, diplomas, or other qualifications pursued by post-secondary students who have earned an undergraduate (bachelor's) degree.
The organization and s ...
, V. C. A. Ferraro, predicted the presence of the magnetosphere
In astronomy and planetary science, a magnetosphere is a region of space surrounding an astronomical object in which charged particles are affected by that object's magnetic field. It is created by a celestial body with an active interior d ...
in the early 1930s. They also predicted characteristics of the magnetosphere that were confirmed 30 years later by the Explorer 12 satellite.[
In 1940, Chapman and a German colleague ]Julius Bartels
Julius Bartels (17 August 1899, Magdeburg – 6 March 1964) was a German geophysicist and statistician who made notable contributions to the physics of the Sun and Moon; to geomagnetism and meteorology; and to the physics of the ionosphere. He a ...
published a book in two volumes on geomagnetism, which was to become the standard text book for the next two decades.[ In 1946 Chapman coined the term: Aeronomy, which is used today to describe the scientific field of high-altitude research into atmosphere/space interaction.
From 1951 to 1954, Chapman was President of the ]International Union of Geodesy and Geophysics
The International Union of Geodesy and Geophysics (IUGG; french: Union géodésique et géophysique internationale, UGGI) is an international non-governmental organization dedicated to the scientific study of Earth and its space environment us ...
(IUGG).
Chapman was President of the Special Committee for the International Geophysical Year
The International Geophysical Year (IGY; french: Année géophysique internationale) was an international scientific project that lasted from 1 July 1957 to 31 December 1958. It marked the end of a long period during the Cold War when scientific i ...
(IGY). The idea of the IGY stemmed from a discussion in 1950 between Chapman and scientists including James Van Allen
James Alfred Van Allen (September 7, 1914August 9, 2006) was an American space scientist at the University of Iowa. He was instrumental in establishing the field of magnetospheric research in space.
The Van Allen radiation belts were named aft ...
. 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
A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioiso ...
launches.
Honours and awards
Chapman was bestowed many honours over his career including Smith's Prize
The Smith's Prize was the name of each of two prizes awarded annually to two research students in mathematics and theoretical physics at the University of Cambridge from 1769. Following the reorganization in 1998, they are now awarded under the n ...
in 1913, election as a Fellow of the Royal Society
Fellowship of the Royal Society (FRS, ForMemRS and HonFRS) is an award granted by the judges of the Royal Society of London to individuals who have made a "substantial contribution to the improvement of natural knowledge, including mathemati ...
in 1919, Invited Speaker of the ICM in 1924, Royal Society Bakerian lecture
The Bakerian Medal is one of the premier medals of the Royal Society that recognizes exceptional and outstanding science. It comes with a medal award and a prize lecture. The medalist is required to give a lecture on any topic related to physical ...
r in 1931, Royal Society Royal Medal
The Royal Medal, also known as The Queen's Medal and The King's Medal (depending on the gender of the monarch at the time of the award), is a silver-gilt medal, of which three are awarded each year by the Royal Society, two for "the most important ...
in 1934, London Mathematical Society
The London Mathematical Society (LMS) is one of the United Kingdom's learned societies for mathematics (the others being the Royal Statistical Society (RSS), the Institute of Mathematics and its Applications (IMA), the Edinburgh Mathematical ...
De Morgan Medal in 1944. In 1949, he was awarded the Gold Medal of the Royal Astronomical Society
The Gold Medal of the Royal Astronomical Society is the highest award given by the Royal Astronomical Society (RAS). The RAS Council have "complete freedom as to the grounds on which it is awarded" and it can be awarded for any reason. Past awar ...
and was elected as a Fellow of the Royal Society of Edinburgh
Fellowship of the Royal Society of Edinburgh (FRSE) is an award granted to individuals that the Royal Society of Edinburgh, Scotland's national academy of science and letters, judged to be "eminently distinguished in their subject". This socie ...
in 1953. In 1964, he was awarded the Copley Medal
The Copley Medal is an award given by the Royal Society, for "outstanding achievements in research in any branch of science". It alternates between the physical sciences or mathematics and the biological sciences. Given every year, the medal is t ...
of the Royal Society
The Royal Society, formally The Royal Society of London for Improving Natural Knowledge, is a learned society and the United Kingdom's national academy of sciences. The society fulfils a number of roles: promoting science and its benefits, re ...
and in 1965 the Symons Gold Medal The Symons Gold Medal is awarded biennially by the Royal Meteorological Society for distinguished work in the field of meteorological science.
It was established in 1901 in memory of George James Symons, a notable British meteorologist.
Recipients ...
of the Royal Meteorological Society
The Royal Meteorological Society is a long-established institution that promotes academic and public engagement in weather and climate science. Fellows of the Society must possess relevant qualifications, but Associate Fellows can be lay enthus ...
. He was elected to the National Academies of Science of the United States, Norway, Sweden and Finland. He served as President of the London Mathematical Society
The London Mathematical Society (LMS) is one of the United Kingdom's learned societies for mathematics (the others being the Royal Statistical Society (RSS), the Institute of Mathematics and its Applications (IMA), the Edinburgh Mathematical ...
during 1929–1931 and the Royal Meteorological Society
The Royal Meteorological Society is a long-established institution that promotes academic and public engagement in weather and climate science. Fellows of the Society must possess relevant qualifications, but Associate Fellows can be lay enthus ...
1932–1933.
The lunar Crater Chapman is named in his honour, as is the Sydney Chapman Building on the campus of the University of Alaska Fairbanks
The University of Alaska Fairbanks (UAF or Alaska) is a public land-grant research university in College, Alaska, a suburb of Fairbanks. It is the flagship campus of the University of Alaska system. UAF was established in 1917 and opened for c ...
. This building served as the first permanent home of the University of Alaska Geophysical Institute, and it now contains the Department of Computer Science and the Department of Mathematics and Statistics. The American Geophysical Union
The American Geophysical Union (AGU) is a 501(c)(3) nonprofit organization of Earth, atmospheric, ocean, hydrologic, space, and planetary scientists and enthusiasts that according to their website includes 130,000 people (not members). AGU's ...
organises "Chapman Conferences," which are small, topical meetings intended to foster innovative research in key areas. The Royal Astronomical Society
(Whatever shines should be observed)
, predecessor =
, successor =
, formation =
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founded the Chapman Medal
The Chapman Medal is an award of the Royal Astronomical Society, given for "investigations of outstanding merit in the science of the Sun, space and planetary environments or solar-terrestrial physics". It is named after Sydney Chapman (1888� ...
in his memory.
Personal life
In 1970, Chapman died in Boulder, Colorado
Boulder is a home rule city that is the county seat and most populous municipality of Boulder County, Colorado, United States. The city population was 108,250 at the 2020 United States census, making it the 12th most populous city in Colora ...
, at the age of 82.
References
{{DEFAULTSORT:Chapman, Sydney
1888 births
1970 deaths
People from Eccles, Greater Manchester
20th-century English mathematicians
Academics of the Victoria University of Manchester
Alumni of the Victoria University of Manchester
Alumni of the University of Salford
Alumni of Trinity College, Cambridge
British geophysicists
De Morgan Medallists
20th-century British astronomers
English physicists
Fellows of The Queen's College, Oxford
Fellows of the Royal Society
Foreign associates of the National Academy of Sciences
Members of the Lincean Academy
Fellows of the American Physical Society
Presidents of the Physical Society
Presidents of the Royal Meteorological Society
Recipients of the Copley Medal
Recipients of the Gold Medal of the Royal Astronomical Society
Royal Medal winners
Sedleian Professors of Natural Philosophy
University of Alaska Fairbanks faculty
Presidents of the Royal Astronomical Society
Plasma physicists
Presidents of the International Union of Geodesy and Geophysics