Dunham Jackson

Dunham Jackson (born July 24, 1888 in Bridgewater (Massachusetts) , † November 6, 1946 ) was an American mathematician who dealt with real analysis (approximation theory, orthogonal functions).

Jackson studied at Harvard from 1904 (Bachelor in 1908, Master in 1909), among others with Maxime Bôcher , and then with a scholarship from 1909 to 1911 at the University of Göttingen . He received his doctorate in 1911 under Edmund Landau in Göttingen ( On the accuracy of the approximation of continuous functions by whole rational functions of given degree and trigonometric sums of given order ). The work won a prize from the Göttingen faculty, but was never published. He was an instructor at Harvard from 1911 and an assistant professor from 1916. During World War I he worked in the US Army's ballistics department with Forest Ray Moulton . From 1919 he was a professor at the University of Minnesota in Minneapolis , which he remained until his death. In his final years, however, his apprenticeship was hampered by a severe heart attack in 1940.

Jackson's main area of ​​work was approximation theory . A connection that he found in his dissertation between the continuity module of a continuous function and the error of the best approximation using polynomials of fixed degree is now called Jackson's theorem or Jackson inequality. The analogue (which also goes back to him) for approximation of periodic continuous functions by trigonometric polynomials is so called. Jackson occupied himself with other mathematical fields, in particular he also worked on statistics in later years.

In 1915 Jackson was elected to the American Academy of Arts and Sciences . In 1921 he was Vice President of the American Mathematical Society , whose Colloquium Lecturer he was in 1925. From 1924 to 1925 he was vice president and 1926 president of the Mathematical Association of America . In 1935 he received the Chauvenet Prize and was elected a member of the National Academy of Sciences . In 1936 he became a Fellow of the American Physical Society .

Jackson had been married since 1918 and had two daughters.

literature

• Dunham Jackson: About the accuracy of the approximation of continuous functions by whole rational functions of given degree and trigonometric sums of given order. Dissertation, Göttingen, Dieterich, 1911.
• Dunham Jackson: Fourier Series and Orthogonal Polynomials. Carus Mathematical Monographs, 1941.
• William Hart: Obituary in Bulletin AMS. Volume 54, 1946, p. 847.

Web links

• Member Directory: Dunham Jackson. National Academy of Sciences, accessed December 4, 2015 (Biographical Memoir by William L. Hart). 
• Dunham Jackson in the Mathematics Genealogy Project (English)