Jim Simons

Simons had a complete career before he had a trading career. He took his mathematics degree at MIT and his doctorate at Berkeley by twenty-three, did cryptanalytic work during the Vietnam era, chaired the mathematics department at Stony Brook, and co-developed Chern–Simons theory — deep, abstract differential geometry that later found application in quantum field theory and won him the Veblen Prize. He could have stopped there and been remembered as one of the best geometers of his generation.

He left in 1978, at forty, to trade currencies. The early firms — Monemetrics and Limroy — merged into Renaissance Technologies in 1982, and the Medallion Fund launched in 1988. What made Renaissance unlike its competitors was staffing: physicists, mathematicians, statisticians and computer scientists rather than traders or MBAs, on the theory that finance is learnable and scientific talent is not. Researchers tested obscure signals across enormous datasets; almost none survived, and the few that did were scaled ruthlessly.

Medallion's reported performance has no parallel in the record — figures around 62–66% gross annually across roughly three decades, and something near 37–39% after the fund's unusual fee structure. Those numbers come from journalism and secondary analysis rather than public audit, sources disagree on the exact window, and the fund has long been closed to outside money and run for employees. Simons died on 10 May 2024. He is included in this library not because his method is reproducible — it emphatically is not — but because one principle underneath it is.