Hardest Math Problems: Unsolved Mysteries & Complex Theories

Determining the hardest math question is subjective and can vary depending on who you ask. Some may argue that the most challenging problems are those that remain unsolved, such as the Riemann Hypothesis or the Birch and Swinnerton-Dyer Conjecture. Others may consider problems that require a deep understanding of multiple areas of mathematics to be the most difficult, like the Poincaré conjecture or the Langlands program. Ultimately, what one person finds difficult may not be the same for another.