OAI/Geometry/SurfaceImmersion/Whitney/QuadraticCrosscapPreparation.lean
1 declarations, 0 contain sorry, 0 declared as axioms
Replacing an actual nondegenerate crosscap by its quadratic jet on a smaller neighborhood, while creating no further singularities.
- theorem
OAI.ClosedSurfaceR4.FiniteOrderSmoothing.quadratic_crosscap_preparationline 15