OAI/Geometry/Arnold/Deformation.lean

GitHub source file

13 declarations, 0 contain sorry, 0 declared as axioms

  1. lemma OAI.ArnoldCounterexample.CriticalBound.unit_phase line 15
  2. lemma OAI.ArnoldCounterexample.CriticalBound.project_phase line 21
  3. lemma OAI.ArnoldCounterexample.CriticalBound.project_eq_phase line 26
  4. lemma OAI.ArnoldCounterexample.CriticalBound.extension_phase line 34
  5. lemma OAI.ArnoldCounterexample.CriticalBound.local_lift_derivative_eq line 42

    Source documentation

    Every local lift has the same horizontal derivative as a global extension; this follows from the explicit curves in the actual quadric.

    lemma local_lift_derivative_eq {h : Q3 → ℝ} {G : CV → ℝ}
        (hG : ContDiff ℝ ∞ G) (hGagree : ∀ z : UnitQuadric, G z = h (project z))
        (z : UnitQuadric) (U : Set CV) (g : CV → ℝ)
        (hg : LocalFunctionLift h z U g) (v : CV) (hv : Horizontal z v) :
        fderiv ℝ g z v = fderiv ℝ G z v := by
    …

    Mentions: OAI.ArnoldCounterexample.Q3, OAI.ArnoldCounterexample.CV, OAI.ArnoldCounterexample.UnitQuadric, OAI.ArnoldCounterexample.project, OAI.ArnoldCounterexample.LocalFunctionLift, OAI.ArnoldCounterexample.Horizontal

  6. lemma OAI.ArnoldCounterexample.CriticalBound.stationary_isCritical line 63
  7. theorem OAI.ArnoldCounterexample.CriticalBound.exists_smooth_descent line 83

    Source documentation

    Smooth phase-equivariant, strictly descending discrete deformation of the literal quadric. This supplies the deformation step for arbitrary smooth functions, including highly degenerate ones, without assuming an ODE existence theorem.

    theorem exists_smooth_descent {h : Q3 → ℝ} {G : CV → ℝ}
        (hG : ContDiff ℝ ∞ G) (hGagree : ∀ z : UnitQuadric, G z = h (project z)) :
        ∃ D : CV → CV, ContDiff ℝ ∞ D ∧
          (∀ z : UnitQuadric, IsUnitQuadric (D z)) ∧
          (∀ z : UnitQuadric, ∀ a : ℂ, Complex.normSq a = 1 → D (a • (z : CV)) = a • D z) ∧
          (∀ z : UnitQuadric, G (D z) ≤ G z) ∧
          (∀ z : UnitQuadric, G (D z) = G z → IsCritical h (project z)) := by
    …

    Mentions: OAI.ArnoldCounterexample.Q3, OAI.ArnoldCounterexample.CV, OAI.ArnoldCounterexample.UnitQuadric, OAI.ArnoldCounterexample.project, OAI.ArnoldCounterexample.IsUnitQuadric, OAI.ArnoldCounterexample.IsCritical

  8. lemma OAI.ArnoldCounterexample.CriticalBound.critical_chart line 117
  9. lemma OAI.ArnoldCounterexample.CriticalBound.contDiff_iterate line 133
  10. lemma OAI.ArnoldCounterexample.CriticalBound.iterate_preserves line 139
  11. lemma OAI.ArnoldCounterexample.CriticalBound.iterate_phase line 146
  12. theorem OAI.ArnoldCounterexample.CriticalBound.cover_map line 158

    Source documentation

    Three or fewer critical points yield three nonvanishing-coordinate descent charts, on the literal quadric, with no Morse or nondegeneracy hypotheses.

    theorem cover_map (h : SmoothFunction) (hsmall : (criticalSet h).encard ≤ 3) :
        ∃ F : CV → CSpace 3, ContDiff ℝ ∞ F ∧
          (∀ z : UnitQuadric, F z ≠ 0) ∧
          (∀ z : UnitQuadric, ∀ a : ℂ, Complex.normSq a = 1 → F (a • (z : CV)) = a • F z) := by
    …

    Mentions: OAI.ArnoldCounterexample.SmoothFunction, OAI.ArnoldCounterexample.criticalSet, OAI.ArnoldCounterexample.CV, OAI.ArnoldCounterexample.UnitQuadric

  13. theorem OAI.ArnoldCounterexample.CriticalBound.normalize_cover_map line 217

    Source documentation

    Normalization has a globally smooth ambient extension, even away from K. The positive complement bump prevents spurious singularities off K.

    theorem normalize_cover_map {F : CV → CSpace 3} (hF : ContDiff ℝ ∞ F)
        (hne : ∀ z : UnitQuadric, F z ≠ 0)
        (hphase : ∀ z : UnitQuadric, ∀ a : ℂ, Complex.normSq a = 1 → F (a • (z : CV)) = a • F z) :
        ∃ F' : CV → CSpace 3, ContDiff ℝ ∞ F' ∧
          (∀ z : UnitQuadric, normSq 3 (F' z) = 1) ∧
          (∀ z : UnitQuadric, ∀ a : ℂ, Complex.normSq a = 1 → F' (a • (z : CV)) = a • F' z) := by
    …

    Mentions: OAI.ArnoldCounterexample.CV, OAI.ArnoldCounterexample.UnitQuadric