 Intrinsic flat distance

Intrinsic flat distance is a concept from Riemannian geometry and metric geometry. It is used to compare the "shapes" of Riemannian manifolds, particularly in the context of measuring how closely two manifolds can be approximated by simpler geometric structures. The intrinsic flat distance is particularly useful in the context of spaces that may not have a smooth structure but still possess some geometric features that can be studied.