David Van Dantzig

Dutch mathematician and statistician, after his death honoured as a mathematical omnivore. He was the son of Abraham van Dantzig (28 April 1872, Den Haag - 11 February 1944, Amsterdam) and Bertha de Kadt (28 February 1869, Oss - 30 October 1920, Amsterdam). They married 24 Augustus 1899 in Rotterdam and got at least three children. David van Dantzig (23 September 1900, Amsterdam - 22 July 1959, Amsterdam) became a noted mathematician. Siegfried van Dantzig (2 October 1902, Amsterdam - 8 April 1903, Amsterdam) died early. Marijn van Dantzig (8 December 1904, Amsterdam - 5 April 1996, Rotterdam) became a speech and language therapist (Dutch: logopedist). His mother's mother, Maria van Leeuwen (14 October 1834, Oss - 7 December 1920, Rotterdam) died soon after his mother. At age 13, he wrote his first mathematics paper. He followed the Higher civil school in Amsterdam and began the study Chemistry at the University of Amsterdam in September 1917, where Gerrit Mannoury lectured the for Chemistry needed analytical mathematics. In October 1917 he wrote Gerrit Mannoury a long letter as he was not satisfied with Mannoury's definition of the word "rechte" (straight line). Mannoury appreciated his concerns and promised to come back on it in his next lecture. Is was the start of a long lasting friendship of mathematicians that would support relativity theory. But as his father got less income, he had to work for his income, and only became a Doctor of Philosophy at the University of Groningen in 27 March 1931 with his thesis "Studien over topologische algebra" under supervision of his friend Bartel Leendert van der Waerden. One of his studies was "Ueber topologisch homogene Kontinua, Fund. Math. 15 (1930)". He was appointed professor of Mathematics at the Delft University of Technology in 1938, and at the University of Amsterdam in 1946 in the "Leer der collectieve verschijnselen" (Teachings of collective phenomena). It is of interest that he, being of Jewish descent, was collectively fired on 22 November 1940 by a Nazi decision (Berufsverbote). When he and other Jewish professors could not appear on their scheduled last lectures planned on 23 November 1940, the Technical Students started a strike (Delftse studentenstaking) after a speech of Johan Barthold Frans van Hasselt (26 February 1913, Den Haag - 10 November 1942, Buchenwald). Van Dantzig and his family had to go underground in Amsterdam. Among his Amsterdam doctoral students were Jan Hemelrijk (28 May 1918, Arnhem - 16 March 2005) on 13 December 1950 (Symmetrietoetsen en andere toepassingen van de theorie van Neyman en Pearson), Johan Kemperman (1950), David Johannes Stoker (1955), and Constance van Eeden (1958). In Amsterdam he was one of the founders of the Mathematisch Centrum. At the University of Amsterdam he was succeeded by his brilliant student Jan Hemelrijk. Originally working on topics in differential geometry and topology, he later turned to probability calculation, emphasizing the applicability of statistical hypothesis testing. On 17 June 1949, he became member of the physics department of Royal Netherlands Academy of Arts and Sciences. After the rampant North Sea flood of 31 January 1953, he took a part in the research group preparing the now completed Delta Works. The Delta commission had to decide what measures were necessary to prevent another rampant dike break. The commission initially set the acceptable risk for complete failure of every "dike ring" in the country at 1 in 125,000 years. But this level of protection was too expensive to implement. Thereafter the commission set "acceptable" risks by region: For the densely populated North and South Holland: 1 per 10,000 years, for other areas at risk from sea flooding: 1 per 4,000 years. River flooding causing less damage than salt water flooding, and also having a longer warning time enabling evacuation, got accepatable risks from 1 per 1,250 years for South Holland to 1 per 250 years for other areas. He died 22 July 1959 in Amsterdam. Personal On 27 Mar 1929 he married Elisabeth Mathilde Stumpfrock (24 April 1902, Frankfurt am Main - 23 January 1982, Amsterdam). They got three children: - Rene van Dantzig (?), a retired subatomic and particle physicist .. - Sonja van Dantzig (2 June 1931, Rotterdam - 31 May 2012, Amsterdam), who married the pathologist Stanley Morson Bellot (10 December 1929, Paramaribo - 20 June 2005, Amsterdam) . - Émile Claude van Dantzig (15 July 1947 - 30 April 2014 ), who married twice. Link to Wikipedia