OAI/Geometry/SurfaceImmersion/Primitive/VelocityCircleLift.lean

GitHub source file

7 declarations, 0 contain sorry, 0 declared as axioms

Lift a normalized planar loop to the actual four-dimensional velocity plane, retaining its exact mean, length, and leading metric.

  1. def OAI.ClosedSurfaceR4.VelocityFrame.planeLift line 15

    Source documentation

    The fixed orthonormal-plane inclusion, written as a continuous linear map.

    def planeLift (e₁ e₂ : Vec) : LoopDensity.Plane →L[ℝ] Vec :=
    …

    Mentions: OAI.ClosedSurfaceR4.LoopDensity.Plane

  2. lemma OAI.ClosedSurfaceR4.VelocityFrame.planeLift_apply line 18
  3. lemma OAI.ClosedSurfaceR4.VelocityFrame.planeLift_unit line 21
  4. lemma OAI.ClosedSurfaceR4.VelocityFrame.planeLift_perp line 30
  5. lemma OAI.ClosedSurfaceR4.VelocityFrame.planeLift_scaled_length line 34
  6. lemma OAI.ClosedSurfaceR4.VelocityFrame.planeLift_mean line 42
  7. theorem OAI.ClosedSurfaceR4.VelocityFrame.real_leading_metric line 52

    Source documentation

    The real coordinate form of the leading rank-one metric identity.

    theorem real_leading_metric {X Y C V : Vec} {a : ℝ}
        (hD : gramDet Y C ≠ 0) (hYV : Y ⬝ᵥ V = 0) (hCV : C ⬝ᵥ V = 0)
        (hR : V ⬝ᵥ V = realNormalPart Y C X ⬝ᵥ realNormalPart Y C X + a ^ 2) :
        leadingTangent X Y C V ⬝ᵥ leadingTangent X Y C V = X ⬝ᵥ X + a ^ 2 ∧
          leadingTangent X Y C V ⬝ᵥ Y = X ⬝ᵥ Y := by
    …

    Mentions: OAI.ClosedSurfaceR4.VelocityFrame.leadingTangent