OAI/Geometry/SurfaceImmersion/Primitive/BoundaryProfileFrame.lean

GitHub source file

4 declarations, 0 contain sorry, 0 declared as axioms

Identification of the five-profile coefficient map with the genuine second fundamental form of a smooth immersion.

  1. def OAI.ClosedSurfaceR4.GeometryPreservation.realBoundaryProfile line 12
  2. lemma OAI.ClosedSurfaceR4.GeometryPreservation.realNormalPart_dot_of_normal line 16
  3. lemma OAI.ClosedSurfaceR4.GeometryPreservation.realBoundaryProfile_regular line 22
  4. theorem OAI.ClosedSurfaceR4.GeometryPreservation.exists_profile_secondFormFrame line 30

    Source documentation

    The scaled longitudinal coefficient is read from z Fxx, so this identification is uniform even when Fxx itself diverges.

    theorem exists_profile_secondFormFrame {F : RField 4} (hF : ContDiff ℝ ∞ F)
        (z : ℝ) (p : Base) (hJ : realBoundaryProfile F z p ∈ regularBoundaryProfiles) :
        ∃ d : SecondFormFrame F p
          (coordinateGauss (realMetric F dx dx) (realMetric F dx dy) (realMetric F dy dy) p),
          d.n = profilePreferred (realBoundaryProfile F z p) ∧
          d.m = profileComplement (realBoundaryProfile F z p) ∧
          profileCoefficients (realBoundaryProfile F z p) = ![d.S,d.D,d.N,z*d.L] := by
    …

    Mentions: OAI.ClosedSurfaceR4.GeometryPreservation.realBoundaryProfile, OAI.ClosedSurfaceR4.GeometryPreservation.regularBoundaryProfiles, OAI.ClosedSurfaceR4.GeometryPreservation.SecondFormFrame, OAI.ClosedSurfaceR4.GeometryPreservation.profilePreferred, OAI.ClosedSurfaceR4.GeometryPreservation.profileComplement, OAI.ClosedSurfaceR4.GeometryPreservation.profileCoefficients