George Friedrich Bernhard (1826- 1866, German mathematician) is the founder of Riemann geometry. During his doctorate, he studied complex variable functions. He extended the usual concept of function to multi-valued function and introduced the intuitive concept of multi-leaf Riemannian surface. His doctoral thesis was praised by Gauss, and it was also the basis of his work in the next ten years, including the application of complex variable function in Abel integral and θ function, the trigonometric series representation of function, the basis of differential geometry and so on.

Riemann conjecture was put forward by Riemann in 1859. In the process of proving the prime number theorem, Riemann put forward the conclusion that all zeros of Zeta function are on the straight line Res(s) = 1/2. He gave up after his proof failed, because it had little effect on his proof of the prime number theorem. But this problem has not been solved so far, and even a simpler guess than this assumption has not been proved. Many problems in function theory and analytic number theory depend on Riemann hypothesis. The generalized Riemann hypothesis in algebraic number theory has far-reaching influence. If we can prove the Riemann hypothesis, we can solve many problems.