Hale Trotter

Hale Freeman Trotter (30 May 1931 – 17 January 2022) was a Canadian-American mathematician. He was known for the Lie–Trotter product formula, the Steinhaus–Johnson–Trotter algorithm, and the Lang–Trotter conjecture. He was born in Kingston, Ontario.
Trotter died in Princeton, New Jersey on 17 January 2022, aged 90.