Pierre Deligne | What is the Hodge conjecture?

Millennium Prize Problems Lecture 11/12/2025 Speaker: Pierre Deligne, Institute for Advanced Study Title: What is the Hodge conjecture? Abstract: The Hodge conjecture is about projective non-singular complex algebraic varieties. It characterizes the cohomology classes coming from algebraic cycles. I will explain these terms, tell why the conjecture is so hard to attack, and why we care.