What is the most hard math question?

Answer 1

The Clay Millennium Prizes were offered by the Clay Mathematics Institute in Massachusetts back in 2000 for solving one of these seven problems:

• The Birch and Swinnerton-Dyer Conjecture - algebraic number theory
• The Hodge Conjecture - algebraic geometry
• The Navier-Stokes Equations - fluid dynamics
• P=NP Problem - computer science
• Poincare Conjecture - topology (solved)
• The Riemann Hypothesis - prime numbers
• The Mass Gap Hypothesis and Yang-Mills Equations - quantum mechanics

Pick one! There's still a $1,000,000 prize for solving any one of these.