Freeman John Dyson. 15 December 1923—28 February 2020

Abstract

Freeman John Dyson combined a long career with a short attention span, contributing to five fields of mathematics and 11 fields of physics, as well as to theoretical biology, engineering, operations research, literature and public affairs. At the age of 25 he played a key role in the formulation of quantum electrodynamics—the theory of light and matter that gives us our most precise description of much of the physical world—securing a lifetime appointment to the Institute for Advanced Study that allowed him to cultivate his interests without ever becoming an administrator or obtaining a PhD. In addition to his theoretical pursuits, he helped to design a successful nuclear reactor, developed plans for an interplanetary spaceship, advocated for social justice and engaged in early efforts to mitigate the risks of nuclear weapons and anthropogenic climate change. He was a Fellow of the Royal Society for 67 years, 11 months and 7 days, a record exceeded among the Society's scientific Fellows only by Sir Hans Sloane (elected 1685, Fellow for 67 years, 11 months and 20 days), Sir John Davis (elected 1822, Fellow for 68 years and 7 months), and possibly by Jean Chardellou (elected 1702), who is believed to have died aged 107 in 1771, but the precise date is unknown.