Source: wikibot/schwarz-lantern

= Schwarz lantern
{wiki=Schwarz_lantern}

The Schwarz lantern is a geometric object that serves as a counterexample in the field of topology and differential geometry. It demonstrates that certain intuitively reasonable assumptions about the properties of manifolds cannot be universally applied. Specifically, the Schwarz lantern is constructed to show that it is possible to have a collection of regions in a compact manifold, each of which can be continuously deformable to a simpler shape, that do not yield a manifold with the desired topological properties when combined.