About Harold Scott MacDonald Coxeter
Harold Scott MacDonald "Donald" Coxeter () (9 February 1907 – 31 March 2003) was a British-Canadian geometer and mathematician. He is regarded as one of the greatest geometers of the 20th century. Coxeter was born in England and educated at the University of Cambridge, with student visits to Princeton University. He worked for 60 years at the University of Toronto in Canada, from 1936 until his retirement in 1996, becoming a full professor there in 1948. His many honours included membership in the Royal Society of Canada, the Royal Society, and the Order of Canada. He was an author of 12 books, including The Fifty-Nine Icosahedra (1938) and Regular Polytopes (1947). Many concepts in geometry and group theory are named after him, including the Coxeter graph, Coxeter groups, Coxeter's loxodromic sequence of tangent circles, Coxeter–Dynkin diagrams, and the Todd–Coxeter algorithm. Coxeter won an entrance scholarship and went to Trinity in 1926 to read mathematics. Since 1978, the Canadian Mathematical Society have awarded the Coxeter–James Prize in his honor. Wittgenstein selected Coxeter and others to take notes of his lectures, the collection of which later became The Blue Book.
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