OAI/Geometry/Arnold/Deformation.lean
13 declarations, 0 contain sorry, 0 declared as axioms
- lemma
OAI.ArnoldCounterexample.CriticalBound.unit_phaseline 15 - lemma
OAI.ArnoldCounterexample.CriticalBound.project_phaseline 21 - lemma
OAI.ArnoldCounterexample.CriticalBound.project_eq_phaseline 26 - lemma
OAI.ArnoldCounterexample.CriticalBound.extension_phaseline 34 - lemma
OAI.ArnoldCounterexample.CriticalBound.local_lift_derivative_eqline 42Source 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
- lemma
OAI.ArnoldCounterexample.CriticalBound.stationary_isCriticalline 63 - theorem
OAI.ArnoldCounterexample.CriticalBound.exists_smooth_descentline 83Source 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
- lemma
OAI.ArnoldCounterexample.CriticalBound.critical_chartline 117 - lemma
OAI.ArnoldCounterexample.CriticalBound.contDiff_iterateline 133 - lemma
OAI.ArnoldCounterexample.CriticalBound.iterate_preservesline 139 - lemma
OAI.ArnoldCounterexample.CriticalBound.iterate_phaseline 146 - theorem
OAI.ArnoldCounterexample.CriticalBound.cover_mapline 158Source 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
- theorem
OAI.ArnoldCounterexample.CriticalBound.normalize_cover_mapline 217Source 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