Hallard Croft

Hallard Thomas Croft (1936 to 2025) was an English mathematician, born in Bromley on 15 April 1936. He was educated at the City of London School and earned a PhD from the University of Cambridge in 1961 under the supervision of John Edensor Littlewood. A fellow of Peterhouse, Cambridge, from 1963 to 2003, he invented a geometric shape called Croft Tortoise in 1967, and in 1991 he co-authored the book Unsolved Problems in Geometry with Kenneth Falconer and Richard K. Guy. As Director of Studies in mathematics and Senior Fellow he was drawn into a long dispute with Hugh Trevor-Roper after the latter became Master of Peterhouse in 1980, and he was re-elected a Fellow in 1983 without his seniority.