openAI-math-dataset / lean /OAI /Analysis /Conductivity /Geometry /CollarVolumeBound.lean
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Add lean source and binary files (part 15)
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import Mathlib
import OAI.Analysis.Conductivity.Geometry.BoxIteration
import OAI.Analysis.Conductivity.Geometry.TorusFaceIntegration
import OAI.Analysis.Conductivity.Fourier.AngularIntegratedTrace
namespace OAI
noncomputable section
namespace ScalarConductivity
open Set MeasureTheory Filter Topology UnitAddTorus
open scoped NNReal ENNReal
lemma sourceExtendedBox_compact (l r : ℝ) : IsCompact (sourceExtendedBox l r) := isCompact_Icc
theorem sourceExtended_integral_bound {g : (Fin 3 → ℝ) → ℝ}
(hg : Continuous g) (hn : ∀ y,0≤g y) (i j : Fin 4) {l r : ℝ}
(hl : -(1:ℝ)/100≤l) (hr : r≤1/100) :
(∫ x in sourceExtendedBox l r,g (sourceCollarPiece i j x))≤
100*(∫ y in sourceCollarPiece i j '' sourceExtendedBox l r,g y) := by
rw [sourceExtended_integral i j hl hr,←integral_const_mul]
apply setIntegral_mono_on
· exact (hg.comp (sourceCollarPiece_contDiff i j).continuous).continuousOn.integrableOn_compact isCompact_Icc
· have hc : Continuous (fun x : Fin 3 → ℝ => abs ((sourceCollarDerivative i j x).det)) := by
simp_rw [sourceCollarDerivative_det]
unfold sourceCollarRadius squareFace
fun_prop
exact (continuous_const.mul (hc.mul (hg.comp (sourceCollarPiece_contDiff i j).continuous))).continuousOn.integrableOn_compact isCompact_Icc
· exact measurableSet_Icc
· intro x hx
have hh := sourceExtended_jacobian_lower i j hl hr hx
change g (sourceCollarPiece i j x)≤100*(abs ((sourceCollarDerivative i j x).det)*g (sourceCollarPiece i j x))
nlinarith [mul_nonneg (hn (sourceCollarPiece i j x)) (show 0≤abs ((sourceCollarDerivative i j x).det)-1/100 by linarith)]
lemma continuous_collarFace_integral {g : (Fin 3 → ℝ) → ℝ} (hg : Continuous g) (i j : Fin 4) :
Continuous (fun t : ℝ => ∫ a in (-1:ℝ)..1,∫ b in (-1:ℝ)..1,g (sourceCollarPiece i j ![t,a,b])) := by
apply continuous_parametric_unitInterval (f:=fun t a => ∫ b in (-1:ℝ)..1,g (sourceCollarPiece i j ![t,a,b]))
apply continuous_parametric_unitInterval (f:=fun p : ℝ×ℝ => fun b => g (sourceCollarPiece i j ![p.1,p.2,b]))
exact hg.comp ((sourceCollarPiece_contDiff i j).continuous.comp (by fun_prop))
theorem sourceAngular_volume_bound {g : (Fin 3 → ℝ) → ℝ}
(hg : Continuous g) (hn : ∀ y,0≤g y) {l r : ℝ}
(hlr : l≤r) (hl : -(1:ℝ)/100≤l) (hr : r≤1/100) :
(∫ t in l..r,∫ x : UnitAddTorus (Fin 2),g (sourceAngularCollar t x))≤
(100*((1/sourceRadialWidth)/(2*Real.pi))*((1:ℝ)/(2*Real.pi)))*
∑ i : Fin 4,∑ j : Fin 4,∫ y in sourceCollarPiece i j '' sourceExtendedBox l r,g y := by
let c : ℝ := ((1/sourceRadialWidth)/(2*Real.pi))*((1:ℝ)/(2*Real.pi))
have hw : 0<sourceRadialWidth := by norm_num [sourceRadialWidth,sourceHole]
have hc : 0≤c := by dsimp [c]; positivity
have hcont : Continuous (fun t : ℝ => ∫ x : UnitAddTorus (Fin 2),g (sourceAngularCollar t x)) := by
have hcs : Continuous (fun p : ℝ×UnitAddTorus (Fin 2) => sourceAngularCollar p.1 p.2) := by
simpa only [zero_add] using continuous_sourceAngular 0
have hh := continuous_parametric_integral_of_continuous (μ:=volume)
(f:=fun t (x : UnitAddTorus (Fin 2)) => g (sourceAngularCollar t x))
(hg.comp hcs) (s:=univ) isCompact_univ
simpa using hh
have hsum : Continuous (fun t : ℝ => ∑ i : Fin 4,∑ j : Fin 4,
∫ a in (-1:ℝ)..1,∫ b in (-1:ℝ)..1,g (sourceCollarPiece i j ![t,a,b])) :=
continuous_finsetSum _ (fun i _ => continuous_finsetSum _ (fun j _ => continuous_collarFace_integral hg i j))
calc
_≤∫ t in l..r,c*(∑ i : Fin 4,∑ j : Fin 4,
∫ a in (-1:ℝ)..1,∫ b in (-1:ℝ)..1,g (sourceCollarPiece i j ![t,a,b])) :=
intervalIntegral.integral_mono_on hlr (hcont.intervalIntegrable l r)
((continuous_const.mul hsum).intervalIntegrable l r) (fun t _ => integral_sourceAngular_le hg hn t)
_=c*(∑ i : Fin 4,∑ j : Fin 4,∫ x in sourceExtendedBox l r,g (sourceCollarPiece i j x)) := by
rw [intervalIntegral.integral_const_mul]
congr 1
rw [intervalIntegral.integral_finsetSum (fun i _ => (continuous_finsetSum _ (fun j _ => continuous_collarFace_integral hg i j)).intervalIntegrable l r)]
apply Finset.sum_congr rfl
intro i _
rw [intervalIntegral.integral_finsetSum (fun j _ => (continuous_collarFace_integral hg i j).intervalIntegrable l r)]
apply Finset.sum_congr rfl
intro j _
exact (integral_sourceExtendedBox (hg.comp (sourceCollarPiece_contDiff i j).continuous) hlr).symm
_≤c*(∑ i : Fin 4,∑ j : Fin 4,100*(∫ y in sourceCollarPiece i j '' sourceExtendedBox l r,g y)) := by
apply mul_le_mul_of_nonneg_left _ hc
apply Finset.sum_le_sum
intro i _
apply Finset.sum_le_sum
intro j _
exact sourceExtended_integral_bound hg hn i j hl hr
_=_ := by simp_rw [←Finset.mul_sum]; dsimp [c]; ring
end ScalarConductivity
end
end OAI