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Add lean source and binary files (part 69)
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import OAI.Geometry.Immersion.ClosedSurface.TensorCoordinates
namespace OAI
noncomputable section
open Set Complex Bundle Manifold
open scoped ContDiff Matrix Topology Manifold BigOperators
namespace ClosedSurfaceR4.PhaseMean
open ClosedSurfaceR4.SmallModes (Base dx dy)
open ClosedSurfaceR4.QuadraticMean (realMode)
open ClosedSurfaceR4.RealModes (base_decomposition)
abbrev ComplexTensor := Fin 3 → ℂ
def complexEvaluate (A : ComplexTensor) (v w : Base) : ℂ :=
A 0 * (v.1 : ℂ) * (w.1 : ℂ) +
A 1 * ((v.1 : ℂ) * (w.2 : ℂ) + (v.2 : ℂ) * (w.1 : ℂ)) +
A 2 * (v.2 : ℂ) * (w.2 : ℂ)
def complexPullback (J : Base →L[ℝ] Base) : ComplexTensor →L[ℂ] ComplexTensor :=
LinearMap.toContinuousLinearMap {
toFun := fun A i => complexEvaluate A (J (firstDirection i)) (J (secondDirection i))
map_add' := by intro A B; ext i; simp only [complexEvaluate, Pi.add_apply]; ring
map_smul' := by intro c A; ext i; simp only [complexEvaluate, Pi.smul_apply,
smul_eq_mul, RingHom.id_apply]; ring }
def complexPullbackField (χ : Base → Base) (p : Base) : ComplexTensor →L[ℂ] ComplexTensor :=
complexPullback (fderiv ℝ χ p)
lemma complexPullback_apply (J : Base →L[ℝ] Base) (A : ComplexTensor) (i : Fin 3) :
complexPullback J A i = complexEvaluate A (J (firstDirection i)) (J (secondDirection i)) := rfl
lemma complexEvaluate_pullback (J : Base →L[ℝ] Base) (A : ComplexTensor) (v w : Base) :
complexEvaluate (complexPullback J A) v w = complexEvaluate A (J v) (J w) := by
have hv : J v = v.1 • J dx + v.2 • J dy := by
conv_lhs => rw [base_decomposition v]
simp only [map_add, map_smul]
have hw : J w = w.1 • J dx + w.2 • J dy := by
conv_lhs => rw [base_decomposition w]
simp only [map_add, map_smul]
rw [hv, hw]
simp only [complexEvaluate, complexPullback_apply, firstDirection, secondDirection,
Matrix.cons_val_zero, Matrix.cons_val_one, Matrix.cons_val,
Prod.fst_add, Prod.snd_add, Prod.smul_fst, Prod.smul_snd, smul_eq_mul,
Complex.ofReal_add, Complex.ofReal_mul]
ring
lemma complexPullback_comp (J K : Base →L[ℝ] Base) (A : ComplexTensor) :
complexPullback J (complexPullback K A) = complexPullback (K.comp J) A := by
ext i
rw [complexPullback_apply, complexEvaluate_pullback, complexPullback_apply]
rfl
lemma complexPullback_id (A : ComplexTensor) :
complexPullback (ContinuousLinearMap.id ℝ Base) A = A := by
ext i
fin_cases i <;> simp [complexPullback_apply, complexEvaluate, firstDirection,
secondDirection, dx, dy]
lemma realPart_complexPullback (J : Base →L[ℝ] Base) (A : ComplexTensor) :
ClosedSurfaceR4.QuadraticMean.realPart (complexPullback J A) = pullback J (ClosedSurfaceR4.QuadraticMean.realPart A) := by
ext i
change (complexEvaluate A _ _).re = evaluate (ClosedSurfaceR4.QuadraticMean.realPart A) _ _
simp [complexEvaluate, evaluate, ClosedSurfaceR4.QuadraticMean.realPart, Complex.mul_re]
lemma realMode_complexPullback (J : Base →L[ℝ] Base) (A : ComplexTensor) (θ : ℝ) :
realMode θ (complexPullback J A) = pullback J (realMode θ A) := by
unfold realMode
rw [← map_smul, realPart_complexPullback]
lemma complexPullbackField_inverse {χ e : Base → Base} {p : Base}
(hχ : DifferentiableAt ℝ χ p) (he : DifferentiableAt ℝ e (χ p))
(hinv : e ∘ χ =ᶠ[nhds p] id) (A : ComplexTensor) :
complexPullbackField χ p (complexPullbackField e (χ p) A) = A := by
unfold complexPullbackField
rw [complexPullback_comp, ← fderiv_comp p he hχ,
hinv.fderiv_eq, fderiv_id, complexPullback_id]
lemma oscillating_pullback_inverse {χ e : Base → Base} {p : Base}
(hχ : DifferentiableAt ℝ χ p) (he : DifferentiableAt ℝ e (χ p))
(hinv : e ∘ χ =ᶠ[nhds p] id) (A : ComplexTensor) (θ : ℝ) :
pullbackField χ p (realMode θ (complexPullbackField e (χ p) A)) = realMode θ A := by
change pullback (fderiv ℝ χ p) _ = _
rw [← realMode_complexPullback]
exact congrArg (realMode θ) (complexPullbackField_inverse hχ he hinv A)
end ClosedSurfaceR4.PhaseMean
namespace ClosedSurfaceR4.PhaseMean
open ClosedSurfaceR4.SmallModes (Base Field coordDeriv)
lemma contDiffOn_complexEvaluate {U : Set Base} {A : Base → ComplexTensor}
{v w : Base → Base} (hA : ContDiffOn ℝ ∞ A U) (hv : ContDiffOn ℝ ∞ v U)
(hw : ContDiffOn ℝ ∞ w U) :
ContDiffOn ℝ ∞ (fun p => complexEvaluate (A p) (v p) (w p)) U := by
have hvc := Complex.ofRealCLM.contDiff.comp_contDiffOn hv.fst
have hvd := Complex.ofRealCLM.contDiff.comp_contDiffOn hv.snd
have hwc := Complex.ofRealCLM.contDiff.comp_contDiffOn hw.fst
have hwd := Complex.ofRealCLM.contDiff.comp_contDiffOn hw.snd
have h0 := ((contDiffOn_pi.mp hA 0).mul hvc).mul hwc
have h1 := (contDiffOn_pi.mp hA 1).mul ((hvc.mul hwd).add (hvd.mul hwc))
have h2 := ((contDiffOn_pi.mp hA 2).mul hvd).mul hwd
exact (h0.add h1).add h2
lemma contDiffOn_complexPullbackField_apply {U : Set Base} (hU : IsOpen U)
{A : Base → ComplexTensor} {e : Base → Base}
(hA : ContDiffOn ℝ ∞ A U) (he : ContDiffOn ℝ ∞ e U) :
ContDiffOn ℝ ∞ (fun p => complexPullbackField e p (A p)) U := by
apply contDiffOn_pi.mpr
intro i
exact contDiffOn_complexEvaluate hA
(ClosedSurfaceR4.SmallModes.contDiffOn_coordDeriv_vector hU he (firstDirection i))
(ClosedSurfaceR4.SmallModes.contDiffOn_coordDeriv_vector hU he (secondDirection i))
def coordinateTarget (e : Base → Base) (A : Base → ComplexTensor) : Base → ComplexTensor :=
fun p => complexPullbackField e p (A (e p))
lemma contDiffOn_coordinateTarget {U V : Set Base} (hV : IsOpen V)
{A : Base → ComplexTensor} {e : Base → Base}
(hA : ContDiffOn ℝ ∞ A U) (he : ContDiffOn ℝ ∞ e V) (heU : Set.MapsTo e V U) :
ContDiffOn ℝ ∞ (coordinateTarget e A) V :=
contDiffOn_complexPullbackField_apply hV (hA.comp he heU) he
end ClosedSurfaceR4.PhaseMean
end
end OAI