OAI/Geometry/SurfaceImmersion/Atlas/CompactCoordinatePullback.lean

GitHub source file

2 declarations, 0 contain sorry, 0 declared as axioms

Fixed smooth representatives of the coordinate transitions on each compact overlap, with exact local inverses and polynomial tensor transport.

  1. theorem OAI.ClosedSurfaceR4.JetPolynomial.compact_coordinate_representatives line 16

    Source documentation

    Both coordinate maps can be extended off a compact overlap. Their actual inverse identities continue to hold as germs on a smaller open set.

    theorem compact_coordinate_representatives
        (e : OpenPartialHomeomorph Base Base)
        (he : ContDiffOn ℝ ∞ e e.source) (hi : ContDiffOn ℝ ∞ e.symm e.target)
        {K : Set Base} (hK : IsCompact K) (hKe : K ⊆ e.source) :
        ∃ U : Set Base, IsOpen U ∧ K ⊆ U ∧ U ⊆ e.source ∧
          ∃ T S : Base → Base, ContDiff ℝ ∞ T ∧ ContDiff ℝ ∞ S ∧ EqOn T e U ∧
            (∀ x ∈ U, S (T x) = x) ∧
            (∀ x ∈ U, (T ∘ S) =ᶠ[𝓝 (T x)] id) := by
    …

    Mentions: OAI.ClosedSurfaceR4.JetPolynomial.Base

  2. theorem OAI.ClosedSurfaceR4.JetPolynomial.compact_tensor_polynomial_pullback line 54

    Source documentation

    Tensor polynomials have a fixed smooth expression on every compact coordinate overlap; the expression is chosen before the map being evaluated.

    theorem compact_tensor_polynomial_pullback {n : ℕ}
        (P : Fin 3 → Fin n → Expression) (hP : ∀ k r, (P k r).SmoothCoeffs univ)
        (e : OpenPartialHomeomorph Base Base)
        (he : ContDiffOn ℝ ∞ e e.source) (hi : ContDiffOn ℝ ∞ e.symm e.target)
        {K : Set Base} (hK : IsCompact K) (hKe : K ⊆ e.source) :
        ∃ U : Set Base, IsOpen U ∧ K ⊆ U ∧ U ⊆ e.source ∧
            ∃ P' : Fin 3 → Fin n → Expression, (∀ k r, (P' k r).SmoothCoeffs univ) ∧
              ∀ (G H : Base → Space), ContDiff ℝ ∞ G → ContDiff ℝ ∞ H →
                (∀ x ∈ U, H x = G (e x)) → ∀ (ε t : ℝ) (x : Base), x ∈ U →
                  Perturbation.coordinatePolynomialValue P' ε H t (planeCoordinateIsometry x) =
                    tensorCoordinatePullbackValue e x
                      (Perturbation.coordinatePolynomialValue P ε G t
    …

    Mentions: OAI.ClosedSurfaceR4.JetPolynomial.Expression, OAI.ClosedSurfaceR4.JetPolynomial.Base, OAI.ClosedSurfaceR4.JetPolynomial.Space, OAI.ClosedSurfaceR4.JetPolynomial.Perturbation.coordinatePolynomialValue, OAI.ClosedSurfaceR4.JetPolynomial.planeCoordinateIsometry, OAI.ClosedSurfaceR4.JetPolynomial.tensorCoordinatePullbackValue