noun
Riemannian geometry
A branch of differential geometry that studies Riemannian manifolds, smooth manifolds with a Riemannian metric.
リーマン幾何学は一般相対性理論の数学的基礎である。
Riemannian geometry is the mathematical foundation of general relativity.
From the name of the German mathematician Bernhard Riemann (リーマン) and 幾何学 (geometry).