Bernhard Riemann

Georg Friedrich Bernhard Riemann (1826–1866) studied under Gauss and Dirichlet at Göttingen. In his 1854 habilitation lecture, 'On the Hypotheses Which Lie at the Bases of Geometry', Riemann created Riemannian geometry, generalizing geometry to multidimensional curved manifolds governed by metric tensors. Six decades later, Albert Einstein utilized Riemannian geometry to formulate general relativity.

In complex analysis, Riemann introduced Riemann surfaces and the Riemann mapping theorem. In his 1859 number theory paper, he investigated the analytic continuation of the zeta function and proposed the Riemann Hypothesis regarding its non-trivial zeros, which remains the most famous unsolved conjecture in mathematics.