Mathematician Isadore Singer dies

Erik Verlinde tweets:

I am very sad to learn about the passing of Isadore Singer. He was not only one of the greatest mathematician of the last half century, but also one of the friendliest people I have met. In my view, he was the only mathematician with a deep understanding of theoretical physics.

NY Times obituary.

Math genealogy, where you can trace him back to Gauss, Leibniz, and others.