There are seven mathematical problems in the world. At present, Poincare conjecture and Riemann hypothesis have been solved. The remaining questions are as follows:

1, n P complete problem: it is a problem that uncertain Turing machine can solve in p time, and it is the "most difficult" problem in NP class, that is, they are most likely not to belong to P class, because any NP problem can be transformed into a special case of any specific NP complete problem in polynomial time;

2. Hodge conjecture: it is an important unsolved problem in algebraic geometry. It is a conjecture about the algebraic topology of nonsingular complex algebraic clusters and its correlation with the geometry represented by polynomial equations defining subgroups;

3. Young Mills Theory: It is the basis of modern gauge field theory and provides conditions for studying the structure of hadrons.