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Add lean source and binary files (part 62)
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import OAI.Computability.PerfectCompleteness.Algebra.UniformLinearImage
import OAI.Computability.PerfectCompleteness.Decoding.ChildBlockProjection
namespace OAI
section
namespace PerfectCompleteness.ChildCallNumbering
open RecursiveSpaces TreeSourceSpaces HierarchicalArrays PointwiseSpaces
open UniqueGamesTheorem.Foundations.Games
open scoped Classical
noncomputable section
variable {C : Type*} [Fintype C] {branch : Nat → Nat} {n t : Nat}
abbrev Raw (rows : Nat → Nat) (slots : Slots branch n → Fin t → MixedSupport.Slot) :=
(C → squareSpace (H slots)) × Arrays slots rows
instance rawFintype (rows : Nat → Nat)
(slots : Slots branch n → Fin t → MixedSupport.Slot) :
Fintype (Raw (C := C) rows slots) := Fintype.ofFinite _
instance rawNonempty (rows : Nat → Nat)
(slots : Slots branch n → Fin t → MixedSupport.Slot) :
Nonempty (Raw (C := C) rows slots) := ⟨(fun _ => 0, fun _ _ => 0)⟩
def equiv (rows : Nat → Nat) (slots : Slots branch n → Fin t → MixedSupport.Slot) :
Raw (C := C) rows slots ≃ₗ[F2]
ChildBlockCardinality.Raw (Fintype.card C) rows slots where
toFun x := (fun k => x.1 ((Fintype.equivFin C).symm k), x.2)
invFun x := (fun c => x.1 (Fintype.equivFin C c), x.2)
left_inv x := by
apply Prod.ext
· funext c
simp only [Equiv.symm_apply_apply]
· rfl
right_inv x := by
apply Prod.ext
· funext k
simp only [Equiv.apply_symm_apply]
· rfl
map_add' x y := rfl
map_smul' c x := rfl
@[simp] theorem equiv_calls (rows : Nat → Nat)
(slots : Slots branch n → Fin t → MixedSupport.Slot)
(x : Raw (C := C) rows slots) (k : Fin (Fintype.card C)) :
(equiv rows slots x).1 k = x.1 ((Fintype.equivFin C).symm k) := rfl
@[simp] theorem equiv_arrays (rows : Nat → Nat)
(slots : Slots branch n → Fin t → MixedSupport.Slot)
(x : Raw (C := C) rows slots) : (equiv rows slots x).2 = x.2 := rfl
@[simp] theorem equiv_symm_calls (rows : Nat → Nat)
(slots : Slots branch n → Fin t → MixedSupport.Slot)
(x : ChildBlockCardinality.Raw (Fintype.card C) rows slots) (c : C) :
((equiv (C := C) rows slots).symm x).1 c = x.1 (Fintype.equivFin C c) := rfl
@[simp] theorem equiv_symm_arrays (rows : Nat → Nat)
(slots : Slots branch n → Fin t → MixedSupport.Slot)
(x : ChildBlockCardinality.Raw (Fintype.card C) rows slots) :
((equiv (C := C) rows slots).symm x).2 = x.2 := rfl
def pullback (rows : Nat → Nat)
{slots projected : Slots branch n → Fin t → MixedSupport.Slot}
(p : ∀ s k, MixedSupport.Projection (slots s k) (projected s k)) :
Raw (C := C) rows projected →ₗ[F2] Raw (C := C) rows slots where
toFun x := (fun c => ChildBlockProjection.squarePullback p (x.1 c),
ChildBlockProjection.arraysPullback rows p x.2)
map_add' x y := by
apply Prod.ext
· funext c
exact map_add (ChildBlockProjection.squarePullback p) (x.1 c) (y.1 c)
· exact map_add (ChildBlockProjection.arraysPullback rows p) x.2 y.2
map_smul' a x := by
apply Prod.ext
· funext c
exact map_smul (ChildBlockProjection.squarePullback p) a (x.1 c)
· exact map_smul (ChildBlockProjection.arraysPullback rows p) a x.2
omit [Fintype C] in
@[simp] theorem pullback_calls (rows : Nat → Nat)
{slots projected : Slots branch n → Fin t → MixedSupport.Slot}
(p : ∀ s k, MixedSupport.Projection (slots s k) (projected s k))
(x : Raw (C := C) rows projected) (c : C) :
(pullback rows p x).1 c = ChildBlockProjection.squarePullback p (x.1 c) := rfl
omit [Fintype C] in
@[simp] theorem pullback_arrays (rows : Nat → Nat)
{slots projected : Slots branch n → Fin t → MixedSupport.Slot}
(p : ∀ s k, MixedSupport.Projection (slots s k) (projected s k))
(x : Raw (C := C) rows projected) :
(pullback rows p x).2 = ChildBlockProjection.arraysPullback rows p x.2 := rfl
theorem equiv_pullback (rows : Nat → Nat)
{slots projected : Slots branch n → Fin t → MixedSupport.Slot}
(p : ∀ s k, MixedSupport.Projection (slots s k) (projected s k))
(x : Raw (C := C) rows projected) :
equiv rows slots (pullback rows p x) =
ChildBlockProjection.rawPullback (Fintype.card C) rows p
(equiv rows projected x) := rfl
omit [Fintype C] in
theorem pullback_cast (rows : Nat → Nat)
{slots target projected : Slots branch n → Fin t → MixedSupport.Slot}
(h : slots = target)
(p : ∀ s k, MixedSupport.Projection (slots s k) (projected s k))
(x : Raw (C := C) rows projected) :
cast (congrArg (Raw (C := C) rows) h) (pullback rows p x) =
pullback rows
(cast (congrArg
(fun ss : Slots branch n → Fin t → MixedSupport.Slot =>
∀ s k, MixedSupport.Projection (ss s k) (projected s k)) h) p) x := by
cases h
rfl
theorem uniform_equiv (rows : Nat → Nat)
(slots : Slots branch n → Fin t → MixedSupport.Slot) :
(FiniteDistribution.uniform (Raw (C := C) rows slots)).pushforward
(equiv (C := C) rows slots) =
FiniteDistribution.uniform (ChildBlockCardinality.Raw (Fintype.card C) rows slots) :=
UniformLinearImage.uniform_pushforward_linearMap
(equiv (C := C) rows slots).toLinearMap (equiv (C := C) rows slots).surjective
theorem card_le (rows : Nat → Nat)
(slots : Slots branch n → Fin t → MixedSupport.Slot) :
Fintype.card (Raw (C := C) rows slots) ≤
ChildBlockCardinality.bound branch n t (Fintype.card C) rows := by
calc
Fintype.card (Raw (C := C) rows slots) =
Fintype.card (ChildBlockCardinality.Raw (Fintype.card C) rows slots) :=
Fintype.card_congr (equiv (C := C) rows slots).toEquiv
_ ≤ _ := by
simpa only [Nat.card_eq_fintype_card] using
ChildBlockCardinality.card_le (Fintype.card C) rows slots
end
end PerfectCompleteness.ChildCallNumbering
end
end OAI