Millennium Prize Problems

Five open problems from Clay’s famous prize program, linking mathematics with computation and mathematical physics.

The Clay Mathematics Institute announced seven Millennium Prize Problems in 2000, with a million-dollar prize for each. This view brings together the five it lists as unsolved, as checked on 1 October 2026. The original seven also include the Poincaré conjecture, which has been solved, and Navier–Stokes existence and smoothness. Clay’s 11 September 2026 announcement describes Navier–Stokes as apparently settled while its evaluation process continues; that announcement is not a final prize decision. Follow Clay’s pages for the full program and updates.

Subjects: Mathematics · Computational complexity · Particle physics

Problems in this collection

5 problems

Riemann hypothesis

There are 25 primes up to 100 and 168 up to 1,000. Their uneven counts follow a broad trend; a conjecture about the zeta function predicts how far they can stray from a refined estimate.

P versus NP

A proposed guest list can be checked against the rules. Does easy checking always come with an efficient way to find a list that works?

Birch and Swinnerton-Dyer conjecture

An elliptic curve has both rational solutions and an analytic function. The conjecture predicts that these two ways of studying it encode the same rank.

Hodge conjecture

Some topological features of a complex algebraic shape look as though they should come from smaller algebraic shapes inside it. Must they?

About this collection

  1. The Millennium Prize Problems Clay Mathematics Institute

    The program’s official roster distinguishes five unsolved problems, the active Navier–Stokes problem, and the solved Poincaré conjecture.

  2. Navier-Stokes Announcement Clay Mathematics Institute · 2026-09-11

    Clay reports an apparent resolution and explains that its deliberate evaluation process will continue with updates.

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