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Add lean source and binary files (part 62)
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import OAI.Computability.PerfectCompleteness.Algebra.LowerCrossRank
import OAI.Computability.PerfectCompleteness.Foundations.DualQuotientRowsLemmas
import OAI.Computability.PerfectCompleteness.Sampling.RestrictionRowsLaw
namespace OAI
section
namespace PerfectCompleteness.RestrictionCrossLaw
noncomputable section
open UniqueGamesTheorem.Integration.BinaryLinear (F2)
open UniqueGamesTheorem.Fourier.MatrixRestrictions
open UniqueGamesTheorem.Foundations.Games
open RestrictionRowsLaw DualQuotientRows
variable {E C I : Type*} [AddCommGroup E] [Module F2 E]
[AddCommGroup C] [Module F2 C] [Fintype I]
(W : Submodule F2 E) (C' : Submodule F2 C) (b : Module.Basis I F2 C')
def rowPairEquiv (m : Nat) :
((Fin m ⊕ Fin m) → Module.Dual F2 (E ⧸ W)) ≃ₗ[F2]
((Fin m → W.dualAnnihilator) × (Fin m → W.dualAnnihilator)) :=
(LinearEquiv.piCongrRight
(fun _ : Fin m ⊕ Fin m => quotientRowEquiv W)).trans
(LinearEquiv.sumArrowLequivProdArrow
(Fin m) (Fin m) F2 W.dualAnnihilator)
variable {m : Nat} (sel : (Fin m ⊕ Fin m) → I)
def selectedPair : Parameter W C' →ₗ[F2]
((Fin m → W.dualAnnihilator) × (Fin m → W.dualAnnihilator)) :=
(rowPairEquiv W m).toLinearMap.comp (selectedRowsLinear W C' b sel)
omit [Fintype I] in
@[simp] theorem selectedPair_fst (A : Parameter W C') (i : Fin m) :
(selectedPair W C' b sel A).1 i =
quotientRowEquiv W (rowsLinear W C' b A (sel (Sum.inl i))) := rfl
omit [Fintype I] in
@[simp] theorem selectedPair_snd (A : Parameter W C') (j : Fin m) :
(selectedPair W C' b sel A).2 j =
quotientRowEquiv W (rowsLinear W C' b A (sel (Sum.inr j))) := rfl
theorem selectedPair_surjective (hsel : Function.Injective sel) :
Function.Surjective (selectedPair W C' b sel) :=
(rowPairEquiv W m).surjective.comp (selectedRowsLinear_surjective W C' b sel hsel)
private theorem uniform_product {A B : Type*} [Fintype A] [Fintype B]
[Nonempty A] [Nonempty B] :
(FiniteDistribution.uniform A).product (FiniteDistribution.uniform B) =
FiniteDistribution.uniform (A × B) := by
apply FiniteDistribution.eq_of_weight_eq
intro p
change (1 / (Fintype.card A : ℝ)) * (1 / (Fintype.card B : ℝ)) =
1 / (Fintype.card (A × B) : ℝ)
simp only [Fintype.card_prod, Nat.cast_mul, one_div, mul_inv]
theorem selectedPair_law [Fintype (Parameter W C')] [Fintype W.dualAnnihilator]
(hsel : Function.Injective sel) :
(FiniteDistribution.uniform (Parameter W C')).pushforward (selectedPair W C' b sel) =
(FiniteDistribution.uniform (Fin m → W.dualAnnihilator)).product
(FiniteDistribution.uniform (Fin m → W.dualAnnihilator)) := by
rw [uniform_product]
exact UniformLinearImage.uniform_pushforward_linearMap
(selectedPair W C' b sel) (selectedPair_surjective W C' b sel hsel)
omit [Fintype I] in
theorem coordinate_translate_left (coordinates : I → Module.Dual F2 C)
(hcoordinates : ∀ i, (coordinates i).comp C'.subtype = b.coord i)
(X : E →ₗ[F2] C) (A : Parameter W C') (i : Fin m) :
(coordinates (sel (Sum.inl i))).comp (translate W C' X A) =
(coordinates (sel (Sum.inl i))).comp X +
((selectedPair W C' b sel A).1 i : Module.Dual F2 E) := by
simpa only [affineRow, selectedPair_fst, quotientRowEquiv_val] using
coordinate_translate W C' b coordinates hcoordinates X A (sel (Sum.inl i))
omit [Fintype I] in
theorem coordinate_translate_right (coordinates : I → Module.Dual F2 C)
(hcoordinates : ∀ i, (coordinates i).comp C'.subtype = b.coord i)
(X : E →ₗ[F2] C) (A : Parameter W C') (j : Fin m) :
(coordinates (sel (Sum.inr j))).comp (translate W C' X A) =
(coordinates (sel (Sum.inr j))).comp X +
((selectedPair W C' b sel A).2 j : Module.Dual F2 E) := by
simpa only [affineRow, selectedPair_snd, quotientRowEquiv_val] using
coordinate_translate W C' b coordinates hcoordinates X A (sel (Sum.inr j))
theorem crossMatrix_law [Fintype (Parameter W C')] [Fintype W.dualAnnihilator]
(hsel : Function.Injective sel)
(coordinates : I → Module.Dual F2 C)
(hcoordinates : ∀ i, (coordinates i).comp C'.subtype = b.coord i)
(X : E →ₗ[F2] C)
(F : Module.Dual F2 E →ₗ[F2] Module.Dual F2 (Module.Dual F2 E)) :
(FiniteDistribution.uniform (Parameter W C')).pushforward
(Γ := Matrix (Fin m) (Fin m) F2)
(fun A i j =>
F ((coordinates (sel (Sum.inl i))).comp (translate W C' X A))
((coordinates (sel (Sum.inr j))).comp (translate W C' X A))) =
((FiniteDistribution.uniform (Fin m → W.dualAnnihilator)).product
(FiniteDistribution.uniform (Fin m → W.dualAnnihilator))).pushforward
(Γ := Matrix (Fin m) (Fin m) F2)
(fun p => LowerCrossRank.crossMatrix F W.dualAnnihilator
(fun i => (coordinates (sel (Sum.inl i))).comp X)
(fun j => (coordinates (sel (Sum.inr j))).comp X) p.1 p.2) := by
have hcross :
(fun (A : Parameter W C') =>
(fun i j => F ((coordinates (sel (Sum.inl i))).comp (translate W C' X A))
((coordinates (sel (Sum.inr j))).comp (translate W C' X A)) :
Matrix (Fin m) (Fin m) F2)) =
(fun A => LowerCrossRank.crossMatrix F W.dualAnnihilator
(fun i => (coordinates (sel (Sum.inl i))).comp X)
(fun j => (coordinates (sel (Sum.inr j))).comp X)
(selectedPair W C' b sel A).1 (selectedPair W C' b sel A).2) := by
funext A i j
rw [coordinate_translate_left W C' b sel coordinates hcoordinates X A i,
coordinate_translate_right W C' b sel coordinates hcoordinates X A j]
rfl
rw [hcross, ← FiniteDistribution.pushforward_comp
(FiniteDistribution.uniform (Parameter W C')) (selectedPair W C' b sel)
(fun p => LowerCrossRank.crossMatrix F W.dualAnnihilator
(fun i => (coordinates (sel (Sum.inl i))).comp X)
(fun j => (coordinates (sel (Sum.inr j))).comp X) p.1 p.2),
selectedPair_law W C' b sel hsel]
end
end PerfectCompleteness.RestrictionCrossLaw
end
end OAI