Percy John Daniell (9 January 1889 – 25 May 1946) was a pure and

applied mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change. History One ...

Early life and education

Daniell was born in Valparaiso,

Chile Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, stretching along a narrow strip of land between the Andes, Andes Mountains and the Paci ...

. His family returned to

England England is a Countries of the United Kingdom, country that is part of the United Kingdom. It is located on the island of Great Britain, of which it covers about 62%, and List of islands of England, more than 100 smaller adjacent islands. It ...

in 1895. Daniell attended

King Edward's School, Birmingham King Edward's School (KES) is an independent school (UK), independent day school for boys in the British Public school (UK), public school tradition, located in Edgbaston, Birmingham. Founded by Edward VI of England, King Edward VI in 1552, it ...

and proceeded to

Trinity College, Cambridge Trinity College is a Colleges of the University of Cambridge, 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 ...

(where he was the last

Senior Wrangler The Senior Wrangler is the top mathematics undergraduate at the University of Cambridge in England, a position which has been described as "the greatest intellectual achievement attainable in Britain". Specifically, it is the person who achiev ...

in 1909). At this time Daniell was an applied mathematician/

theoretical physicist Theoretical physics is a branch of physics that employs mathematical models and abstractions of physical objects and systems to rationalize, explain, and predict natural phenomena. This is in contrast to experimental physics, which uses experi ...

Mathematical career

For a year he lectured at the

University of Liverpool The University of Liverpool (abbreviated UOL) is a Public university, public research university in Liverpool, England. Founded in 1881 as University College Liverpool, Victoria University (United Kingdom), Victoria University, it received Ro ...

and then he was appointed to the new

Rice Institute The International Rice Research Institute (IRRI) is an international Agricultural science, agricultural research and training organization with its headquarters in Los Baños, Laguna, in the Philippines, and offices in seventeen countries. IRR ...

Houston Houston ( ) is the List of cities in Texas by population, most populous city in the U.S. state of Texas and in the Southern United States. Located in Southeast Texas near Galveston Bay and the Gulf of Mexico, it is the county seat, seat of ...

Texas Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...

. The Rice Institute had him spend a year at the

University of Göttingen The University of Göttingen, officially the Georg August University of Göttingen (, commonly referred to as Georgia Augusta), is a Public university, public research university in the city of Göttingen, Lower Saxony, Germany. Founded in 1734 ...

studying with

Max Born Max Born (; 11 December 1882 – 5 January 1970) was a German-British theoretical physicist who was instrumental in the development of quantum mechanics. He also made contributions to solid-state physics and optics, and supervised the work of a ...

and

David Hilbert David Hilbert (; ; 23 January 1862 – 14 February 1943) was a German mathematician and philosopher of mathematics and one of the most influential mathematicians of his time. Hilbert discovered and developed a broad range of fundamental idea ...

. Daniell was at Rice from 1914 to 1923 when he returned to England to a chair at the

University of Sheffield The University of Sheffield (informally Sheffield University or TUOS) is a public university, public research university in Sheffield, South Yorkshire, England. Its history traces back to the foundation of Sheffield Medical School in 1828, Fir ...

. In a series of papers published between 1918 and 1928, he developed and expanded a generalized theory of integration and differentiation, which is today known as the

Daniell integral In mathematics, the Daniell integral is a type of integration that generalizes the concept of more elementary versions such as the Riemann integral to which students are typically first introduced. One of the main difficulties with the traditional f ...

. In the setting of integration, he also worked on results that lead to the Daniell-Kolmogorov extension theorem in the theory of stochastic processes, independently of

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 Soviet ...

. He was an Invited Speaker of the

ICM ICM may refer to: Organizations * Irish Church Missions, an Anglican mission * Institut du Cerveau, the Paris Brain Institute, a research center * Interdisciplinary Centre for Mathematical and Computational Modelling, University of Warsaw * Interna ...

in 1920 at Strasbourg.

Death

During

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

Daniell advised the British

Ministry of Supply The Ministry of Supply (MoS) was a department of the UK government formed on 1 August 1939 by the Ministry of Supply Act 1939 ( 2 & 3 Geo. 6. c. 38) to co-ordinate the supply of equipment to all three British armed forces, headed by the Ministe ...

. The strain of work during the war took a heavy toll on his health. He died on 25 May 1946, after having collapsed at his home a few weeks earlier.

External links

Aldrich, J. (2007
"But you have to remember P.J.Daniell of Sheffield"
December 2007.

References

* Stewart, C.A. (1947), "P. J. Daniell", ''J. London Math. Soc.'' s1-22: 75–80. * Daniell, Percy John (1918), "A general form of integral", ''Annals of Mathematics'' 19: 279–94. * –––––– (1919a), "Integrals in an infinite number of dimensions", ''Annals of Mathematics'' 20: 281–88. * –––––– (1919b), "Functions of limited variation in an infinite number of dimensions", ''Annals of Mathematics'' 21: 30–38. * –––––– (1920), "Further properties of the general integral", ''Annals of Mathematics'' 21: 203–20. * –––––– (1921), "Integral products and probability", ''American Journal of Mathematics'' 43: 143–62. * –––––– (1946), "Discussion on the Symposium on Autocorrelation in Time Series", ''Supplement to the Journal of the Royal Statistical Society'' 8-1: 88–90. * Shilov, G. E., and Gurevich, B. L. (1978), ''Integral, Measure, and Derivative: A Unified Approach,'' Richard A. Silverman, trans., Dover Publications. 1889 births 1946 deaths University of Göttingen alumni Rice University faculty 20th-century British mathematicians Alumni of Trinity College, Cambridge Senior Wranglers People from Valparaíso People educated at King Edward's School, Birmingham British expatriates in Chile British expatriates in the United States Academics of the University of Sheffield {{UK-mathematician-stub