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Add lean source and binary files (part 19)
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import OAI.Analysis.InterpolatedFactors.Matrices
namespace OAI
noncomputable section
universe u_1 u_2 u_3 u_4 u_5 u_6 u_7 u_8
section
namespace FreeGroupFactorMain.HilbertUltraweak
variable {E : Type u_1} [NormedAddCommGroup E] [InnerProductSpace ℂ E]
variable {X : Type u_2} [TopologicalSpace X]
theorem finset_sum_continuous {ι : Type u_3} (s : Finset ι) (f : ι → X → (E →L[ℂ] E))
(hf : ∀ i∈s,@Continuous _ _ _ (topology E) (f i)) :
@Continuous _ _ _ (topology E) (fun x => ∑ i∈s,f i x) := by
classical
induction s using Finset.induction_on with
| empty => simpa only [Finset.sum_empty] using (@continuous_const X _ _ (topology E) (0 : E →L[ℂ] E))
| @insert a s ha ih =>
simp only [Finset.sum_insert ha]
exact add_continuous (hf a (Finset.mem_insert_self _ _))
(ih (fun i hi => hf i (Finset.mem_insert_of_mem hi)))
end FreeGroupFactorMain.HilbertUltraweak
namespace FreeGroupFactorMain.Amplification
variable {G : Type u_4} {H : Type u_5}
theorem matrixEntry_normal (i j : ℕ) :
@Continuous _ _ (ultraweakOperatorTopology (ℕ × G)) (ultraweakOperatorTopology G)
(fun T : GroupOperator (ℕ × G) => matrixEntry T i j) := by
have hc := HilbertUltraweak.sandwich_continuous (productCoordinate ℕ G i) (productSingle ℕ G j)
convert hc using 1
rfl
theorem matrixBlock_normal (i j : ℕ) :
@Continuous _ _ (ultraweakOperatorTopology G) (ultraweakOperatorTopology (ℕ × G))
(matrixBlock (G := G) i j) :=
HilbertUltraweak.sandwich_continuous (productSingle ℕ G i) (productCoordinate ℕ G j)
variable [Group G] [Group H]
theorem finiteCornerEntry_normal (n : ℕ) (p : groupVonNeumann G) (hp : IsStarProjection p) (i j : Fin n) :
@Continuous _ _ (cornerTopology (stabilizationTopology G) (finiteProjection n p) (finiteProjection_projection n p hp))
(cornerTopology (groupUltraweakTopology G) p hp) (fun x => finiteCornerEntry n p hp x i j) := by
let : TopologicalSpace (GroupOperator (ℕ × G)) := ultraweakOperatorTopology (ℕ × G)
let : TopologicalSpace (GroupOperator G) := ultraweakOperatorTopology G
let : TopologicalSpace (stabilization G) := stabilizationTopology G
let : TopologicalSpace (groupVonNeumann G) := groupUltraweakTopology G
let : TopologicalSpace (FiniteCorner n p hp) := cornerTopology (stabilizationTopology G) (finiteProjection n p) (finiteProjection_projection n p hp)
let : TopologicalSpace (Corner p hp) := cornerTopology (groupUltraweakTopology G) p hp
exact (((matrixEntry_normal i.val j.val).comp (continuous_subtype_val.comp continuous_subtype_val)).subtype_mk _).subtype_mk _
theorem finiteCornerOfMatrix_normal (n : ℕ) (p : groupVonNeumann G) (hp : IsStarProjection p)
{X : Type u_6} [TopologicalSpace X] (f : X → Fin n → Fin n → Corner p hp)
(hf : ∀ i j,@Continuous _ _ _ (cornerTopology (groupUltraweakTopology G) p hp) (fun x => f x i j)) :
@Continuous _ _ _ (cornerTopology (stabilizationTopology G) (finiteProjection n p) (finiteProjection_projection n p hp))
(fun x => finiteCornerOfMatrix n p hp (f x)) := by
let : TopologicalSpace (GroupOperator (ℕ × G)) := ultraweakOperatorTopology (ℕ × G)
let : TopologicalSpace (GroupOperator G) := ultraweakOperatorTopology G
let : TopologicalSpace (stabilization G) := stabilizationTopology G
let : TopologicalSpace (groupVonNeumann G) := groupUltraweakTopology G
let : TopologicalSpace (Corner p hp) := cornerTopology (groupUltraweakTopology G) p hp
have hc : Continuous (fun x => finiteMatrix n (fun i j => ((f x i j).val : GroupOperator G))) := by
apply HilbertUltraweak.finset_sum_continuous
intro i _
apply HilbertUltraweak.finset_sum_continuous
intro j _
exact (matrixBlock_normal i.val j.val).comp (continuous_subtype_val.comp (continuous_subtype_val.comp (hf i j)))
exact (hc.subtype_mk _).subtype_mk _
theorem finiteCornerIso_normal (n : ℕ) (p : groupVonNeumann G) (hp : IsStarProjection p)
(q : groupVonNeumann H) (hq : IsStarProjection q) (e : Corner p hp ≃⋆ₐ[ℂ] Corner q hq)
(he : @Continuous _ _ (cornerTopology (groupUltraweakTopology G) p hp)
(cornerTopology (groupUltraweakTopology H) q hq) e) :
@Continuous _ _ (cornerTopology (stabilizationTopology G) (finiteProjection n p) (finiteProjection_projection n p hp))
(cornerTopology (stabilizationTopology H) (finiteProjection n q) (finiteProjection_projection n q hq))
(finiteCornerIso n p hp q hq e) := by
let : TopologicalSpace (FiniteCorner n p hp) := cornerTopology (stabilizationTopology G) (finiteProjection n p) (finiteProjection_projection n p hp)
let : TopologicalSpace (Corner p hp) := cornerTopology (groupUltraweakTopology G) p hp
let : TopologicalSpace (Corner q hq) := cornerTopology (groupUltraweakTopology H) q hq
exact finiteCornerOfMatrix_normal n q hq _ (fun i j => he.comp (finiteCornerEntry_normal n p hp i j))
end FreeGroupFactorMain.Amplification
end
namespace FreeGroupFactorMain.Amplification
open scoped ENNReal
variable {G : Type u_7}
theorem productSingle_norm (i : ℕ) (ξ : GroupHilbert G) : ‖productSingle ℕ G i ξ‖=‖ξ‖ := by
classical
let : DecidableEq ℕ := Classical.decEq ℕ
simp only [productSingle,ContinuousLinearMap.comp_apply,lp.singleContinuousLinearMap_apply,
ContinuousLinearEquiv.coe_coe,LinearIsometryEquiv.coe_toContinuousLinearEquiv]
rw [LinearIsometryEquiv.norm_map,lp.norm_single (by norm_num : (0 : ℝ≥0∞)<2)]
theorem matrixBlock_productSingle (i j k : ℕ) (T : GroupOperator G) (ξ : GroupHilbert G) :
matrixBlock i j T (productSingle ℕ G k ξ)=if j=k then productSingle ℕ G i (T ξ) else 0 := by
simp only [matrixBlock,ContinuousLinearMap.comp_apply,productCoordinate_productSingle]
split_ifs <;> simp
theorem finiteDiagonal_productSingle (n : ℕ) (T : GroupOperator G) (k : ℕ) (ξ : GroupHilbert G) :
finiteDiagonal n T (productSingle ℕ G k ξ)=if k<n then productSingle ℕ G k (T ξ) else 0 := by
classical
rw [finiteDiagonal_sum]
simp only [sum_apply,matrixBlock_productSingle]
by_cases hk : k<n
· rw [ite_eq_left hk]
let j : Fin n := ⟨k,hk⟩
have he : ∀ i : Fin n,i.val=k ↔ i=j := fun i => (Fin.ext_iff (a := i) (b := j)).symm
simp only [he,Finset.sum_ite_eq',Finset.mem_univ,ite_true]
rfl
· rw [ite_eq_right hk]
apply Finset.sum_eq_zero
intro i _
rw [ite_eq_right]
intro hi
exact hk (hi ▸ i.isLt)
variable [Group G]
theorem finiteProjection_trace (n : ℕ) (p : groupVonNeumann G) (hp : IsStarProjection p)
(a : ℝ) (_ha : 0≤a) (hpa : canonicalTrace p=(a:ℂ)) :
stabilizedProjectionTrace (finiteProjection n p)=ENNReal.ofReal (n*a) := by
classical
have hv : ‖(p : GroupOperator G) (lp.single 2 (1:G) (1:ℂ))‖^2=a := by
apply Complex.ofReal_injective
have hh := canonicalTrace_star_mul p
rw [hp.isSelfAdjoint.star_eq,hp.isIdempotentElem.eq,hpa] at hh
simpa only [Complex.ofReal_pow] using hh.symm
change (∑' k : ℕ,ENNReal.ofReal (‖finiteDiagonal n (p : GroupOperator G) (lp.single 2 (k,1) (1:ℂ))‖^2))=_
have he (k : ℕ) : ENNReal.ofReal (‖finiteDiagonal n (p : GroupOperator G) (lp.single 2 (k,1) (1:ℂ))‖^2)=
if k<n then ENNReal.ofReal a else 0 := by
rw [←productSingle_single,finiteDiagonal_productSingle]
split_ifs
· rw [productSingle_norm,hv]
· simp
simp_rw [he]
rw [tsum_eq_sum (s := Finset.range n)]
· have hh : (∑ k∈Finset.range n,if k<n then ENNReal.ofReal a else 0)=∑ _k∈Finset.range n,ENNReal.ofReal a :=
Finset.sum_congr rfl (fun k hk => ite_eq_left (Finset.mem_range.mp hk))
rw [hh]
simp only [Finset.sum_const,Finset.card_range,nsmul_eq_mul]
rw [ENNReal.ofReal_mul (Nat.cast_nonneg n),ENNReal.ofReal_natCast]
· intro k hk
rw [ite_eq_right (fun h => hk (Finset.mem_range.mpr h))]
theorem stabilizedTrace_matrix (T : stabilization G) :
stabilizedTrace T=∑' k : ℕ,canonicalTrace
(⟨matrixEntry (T : GroupOperator (ℕ × G)) k k,(mem_stabilization_iff_matrix _).mp T.property k k⟩ : groupVonNeumann G) := by
classical
apply tsum_congr
intro k
rw [←productSingle_single,productSingle_inner_left,canonicalTrace_eq_inner]
rfl
theorem finiteCorner_trace (n : ℕ) (p : groupVonNeumann G) (hp : IsStarProjection p) (x : FiniteCorner n p hp) :
stabilizedTrace x.val=∑ i : Fin n,canonicalTrace (finiteCornerEntry n p hp x i i).val := by
classical
rw [stabilizedTrace_matrix]
have he (k : ℕ) : canonicalTrace
(⟨matrixEntry (x.val : GroupOperator (ℕ × G)) k k,(mem_stabilization_iff_matrix _).mp x.val.property k k⟩ : groupVonNeumann G)=
if hk : k<n then canonicalTrace (finiteCornerEntry n p hp x ⟨k,hk⟩ ⟨k,hk⟩).val else 0 := by
split_ifs with hk
· rfl
· have hz : matrixEntry (x.val : GroupOperator (ℕ × G)) k k=0 := by
rw [←finiteCorner_reconstruct n p hp x]
exact matrixEntry_finiteMatrix_out n _ k k (Or.inl (le_of_not_gt hk))
have hs : (⟨matrixEntry (x.val : GroupOperator (ℕ × G)) k k,(mem_stabilization_iff_matrix _).mp x.val.property k k⟩ : groupVonNeumann G)=0 := Subtype.ext hz
rw [hs]
exact map_zero (canonicalTraceLinear (G := G))
simp_rw [he]
rw [tsum_eq_sum (s := Finset.range n)]
· rw [←Fin.sum_univ_eq_sum_range]
apply Finset.sum_congr rfl
intro k _
simp only [dite_eq_left k.isLt]
· intro k hk
simp only [dite_eq_right (fun h => hk (Finset.mem_range.mpr h))]
variable {H : Type u_8} [Group H]
theorem finiteCornerIso_trace (n : ℕ) (p : groupVonNeumann G) (hp : IsStarProjection p)
(q : groupVonNeumann H) (hq : IsStarProjection q) (e : Corner p hp ≃⋆ₐ[ℂ] Corner q hq)
(c : ℂ) (hc : ∀ x,canonicalTrace (e x : groupVonNeumann H)=c*canonicalTrace (x : groupVonNeumann G))
(x : FiniteCorner n p hp) :
stabilizedTrace (finiteCornerIso n p hp q hq e x).val=c*stabilizedTrace x.val := by
rw [finiteCorner_trace,finiteCorner_trace,Finset.mul_sum]
apply Finset.sum_congr rfl
intro i _
change canonicalTrace (finiteCornerEntry n q hq (finiteCornerOfMatrix n q hq _) i i).val=_
rw [finiteCornerEntry_ofMatrix,hc]
end FreeGroupFactorMain.Amplification
end
end OAI