Jim Simons, mathematician and hedge fund manager (1938–2024) https://en.wikipedia.org/wiki/Jim_Simons

I assumed you were talking about who I know as james Simons, but just googled him to make sure there wasn't someone else, and yeah - first pic on Google is him with a cigarette. Also learned it was lung cancer that took him out, though he did make it to 86 which isn't bad.

Gross.