Riemann

The Riemann Hypothesis is unproven.

In a spacetime, the Riemann curvature tensor has 256 components, but fortunately they don't all have to be directly calculated thanks to some symmetries.

Unidimensional Riemann integrals are defined by dividing intervals into small subintervals, and multiple integrals can be analogously defined by dividing a square, cube or hypercube into smaller subregions.