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MathlibAnnex/Analysis/CStarAlgebra/CAR/Capture.lean

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1import MathlibAnnex.Analysis.CStarAlgebra.CAR.CaptureRange23/-!4# Full target capture56The surjective cyclic-sum isometry also intertwines the additional target7generators.  The proof compares the two independently constructed strong8shell sums and then identifies the remaining rank-one corner from the9selected-vector transport.  No arbitrary representation is asked to preserve10the source strong-operator limits.11-/1213set_option autoImplicit false14set_option maxHeartbeats 18000001516noncomputable section1718open Filter Topology19open scoped ComplexOrder ENNReal lp InnerProduct2021namespace MathlibAnnex.CStarAlgebra.CAR2223open MathlibAnnex.Analysis.CStarAlgebra24open MathlibAnnex.Analysis.InnerProductSpace2526universe v2728/-- The displayed actual completed-CAR atomic target captures every29irreducible representation on an arbitrary target Hilbert universe. -/30theorem ambientInclusion_unitaryEquivalent31    (family : RepresentativeShellFamily)32    (L : MathlibAnnex.CStarAlgebra.PureState.GNSClass Limit →33      MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ]34        MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState)35    (hLunit : ∀ i, L i ∈ unitary36      (MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ]37        MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState))38    (hLmap : ∀ i, L i39      (MathlibAnnex.CStarAlgebra.PureState.selectedEmbedding completedRootPureState i40        (MathlibAnnex.CStarAlgebra.PureState.selectedVector completedRootPureState i)) =41      MathlibAnnex.CStarAlgebra.PureState.selectedEmbedding completedRootPureState42        completedRootPureState.classOf43        (MathlibAnnex.CStarAlgebra.PureState.selectedVector completedRootPureState44          completedRootPureState.classOf))45    (hLsource : ∀ i n, (L i).comp (selectedAtomicRepresentation46      (transportedFlag family i n - transportedFlag family i (n + 1))) =47        representedShellLink family i n)48    (hLroot : L completedRootPureState.classOf = 1)49    {K : Type v} [NormedAddCommGroup K] [InnerProductSpace ℂ K]50    [CompleteSpace K] (rho : Representation (AtomicTarget L) K)51    (hrho : rho.IsIrreducible) :52    (MathlibAnnex.CStarAlgebra.AtomicConstruction.ambientInclusion selectedAtomicRepresentation L).UnitaryEquivalent53      rho := by54  classical55  let sigma := restrictedRepresentation L rho56  obtain ⟨eta_o, eta, W, hWsurj, heta_o_norm, heta_norm, hWpoint,57      heta_gen, hWsource⟩ :=58    exists_surjective_selectedAtomicCyclicIsometry59      family L hLunit hLsource hLroot rho hrho60  let E : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState ≃ₗᵢ[ℂ] K :=61    LinearIsometryEquiv.ofSurjective W hWsurj62  have hEsource (a : Limit) :63      (E : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ] K).comp64          (selectedAtomicRepresentation a) =65        (sigma a).comp66          (E : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ] K) := by67    change W.toContinuousLinearMap.comp (selectedAtomicRepresentation a) =68      (restrictedRepresentation L rho a).comp W.toContinuousLinearMap69    exact hWsource a70  have hEpoint (i : MathlibAnnex.CStarAlgebra.PureState.GNSClass Limit) :71      E (MathlibAnnex.CStarAlgebra.PureState.selectedEmbedding completedRootPureState i72        (MathlibAnnex.CStarAlgebra.PureState.selectedVector completedRootPureState i)) = eta i := by73    simpa [E] using hWpoint i74  have htargetRoot : MathlibAnnex.CStarAlgebra.AtomicConstruction.generator selectedAtomicRepresentation L75        completedRootPureState.classOf =76      MathlibAnnex.CStarAlgebra.AtomicConstruction.sourceHom selectedAtomicRepresentation L 1 := by77    apply Subtype.ext78    simpa using hLroot79  have hrootGenerator :80      ((Unitary.linearIsometryEquiv81        (representedGeneratorUnitary L hLunit rho82          completedRootPureState.classOf) : K ≃ₗᵢ[ℂ] K) : K →L[ℂ] K) = 1 := by83    change rho (MathlibAnnex.CStarAlgebra.AtomicConstruction.generator selectedAtomicRepresentation L84      completedRootPureState.classOf) = 185    rw [htargetRoot, map_one]86    exact map_one rho87  have heta_root : eta completedRootPureState.classOf = eta_o := by88    have h := heta_gen completedRootPureState.classOf89    change (((Unitary.linearIsometryEquiv90      (representedGeneratorUnitary L hLunit rho91        completedRootPureState.classOf) : K ≃ₗᵢ[ℂ] K) : K →L[ℂ] K)92          (eta completedRootPureState.classOf)) = eta_o at h93    rw [hrootGenerator] at h94    simpa using h95  refine ⟨E, ?_⟩96  intro a97  have hsourceGenerator (i : MathlibAnnex.CStarAlgebra.PureState.GNSClass Limit) (x :98      MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState) :99      E (L i x) =100        rho (MathlibAnnex.CStarAlgebra.AtomicConstruction.generator selectedAtomicRepresentation L i) (E x) := by101    let rho₀ := MathlibAnnex.CStarAlgebra.AtomicConstruction.ambientInclusion selectedAtomicRepresentation L102    let w := (representativeShellData family i).link103    obtain ⟨S₀, T₀, P₀, Q₀, R₀, hS₀, hT₀, -, -, hAdj₀,104        hP₀proj, hP₀range, hQ₀proj, hQ₀range, -, -, hgenerator₀,105        hR₀, -, -, -, -⟩ :=106      exists_targetShellReconstruction family L hLunit hLsource rho₀ i107    obtain ⟨S, T, P, Q, R, hS, hT, -, -, hAdj,108        hPproj, hPrange, hQproj, hQrange, -, -, hgenerator,109        hR, -, -, -, -⟩ :=110      exists_targetShellReconstruction family L hLunit hLsource rho i111    have hrepresented₀ :112        (((Unitary.linearIsometryEquiv113          (representedGeneratorUnitary L hLunit rho₀ i) :114            MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState ≃ₗᵢ[ℂ]115              MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState) :116          MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ]117            MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState)) = L i := by118      rfl119    rw [hrepresented₀] at hgenerator₀ hR₀120    have hS₀' : ContinuousLinearMap.StronglyConverges121        (ContinuousLinearMap.partialSum122          (fun n ↦ selectedAtomicRepresentation (w n))) atTop S₀ := by123      change ContinuousLinearMap.StronglyConverges124        (ContinuousLinearMap.partialSum125          (fun n ↦ selectedAtomicRepresentation126            ((representativeShellData family i).link n))) atTop S₀ at hS₀127      simpa [w] using hS₀128    have hS' : ContinuousLinearMap.StronglyConverges129        (ContinuousLinearMap.partialSum (fun n ↦ sigma (w n))) atTop S := by130      simpa [w] using hS131    have hpartial (N : ℕ) :132        (E : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ] K).comp133            (ContinuousLinearMap.partialSum134              (fun n ↦ selectedAtomicRepresentation (w n)) N) =135          (ContinuousLinearMap.partialSum (fun n ↦ sigma (w n)) N).comp136            (E : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ] K) := by137      apply ContinuousLinearMap.ext138      intro y139      rw [ContinuousLinearMap.comp_apply, ContinuousLinearMap.comp_apply,140        ContinuousLinearMap.partialSum_apply,141        ContinuousLinearMap.partialSum_apply, map_sum]142      apply Finset.sum_congr rfl143      intro n hn144      have h := congrArg145        (fun A : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ] K ↦146          A y) (hEsource (w n))147      simpa [ContinuousLinearMap.comp_apply] using h148    have hSintertwines :149        (E : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ] K).comp S₀ =150        S.comp (E : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ] K) :=151      ContinuousLinearMap.intertwines_strongLimits152        (E : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ] K)153        (E : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ] K)154        hS₀' hS' hpartial155    have hP₀range' : P₀.range =156        ⨅ n, (selectedAtomicRepresentation (transportedFlag family i n)).range := by157      change P₀.range =158        ⨅ n, (selectedAtomicRepresentation (transportedFlag family i n)).range at hP₀range159      exact hP₀range160    have hP₀eq : P₀ = commonFixedProjection161        (fun n ↦ selectedAtomicRepresentation (transportedFlag family i n)) := by162      exact starProjection_eq_commonFixedProjection_of_range_iInf163        selectedAtomicRepresentation (transportedFlag family i)164        (isStarProjection_transportedFlag family i) P₀ hP₀proj hP₀range'165    have hPeq : P = commonFixedProjection166        (fun n ↦ sigma (transportedFlag family i n)) := by167      exact starProjection_eq_commonFixedProjection_of_range_iInf sigma168        (transportedFlag family i) (isStarProjection_transportedFlag family i)169        P hPproj hPrange170    let F₀ : Submodule ℂ171        (MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState) :=172      commonFixedSubspace173        (fun n ↦ selectedAtomicRepresentation (transportedFlag family i n))174    let F : Submodule ℂ K :=175      commonFixedSubspace (fun n ↦ sigma (transportedFlag family i n))176    have hFmap : F₀.map (E.toLinearEquiv :177        MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →ₗ[ℂ] K) = F := by178      ext y179      constructor180      · rintro ⟨z, hz, rfl⟩181        change z ∈ commonFixedSubspace182          (fun n ↦ selectedAtomicRepresentation (transportedFlag family i n)) at hz183        rw [mem_commonFixedSubspace_iff] at hz184        change E z ∈ commonFixedSubspace185          (fun n ↦ sigma (transportedFlag family i n))186        rw [mem_commonFixedSubspace_iff]187        intro n188        have h := congrArg189          (fun A : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ] K ↦190            A z) (hEsource (transportedFlag family i n))191        rw [ContinuousLinearMap.comp_apply, ContinuousLinearMap.comp_apply,192          hz n] at h193        exact h.symm194      · intro hy195        change y ∈ commonFixedSubspace196          (fun n ↦ sigma (transportedFlag family i n)) at hy197        rw [mem_commonFixedSubspace_iff] at hy198        refine ⟨E.symm y, ?_, E.apply_symm_apply y⟩199        change E.symm y ∈ commonFixedSubspace200          (fun n ↦ selectedAtomicRepresentation (transportedFlag family i n))201        rw [mem_commonFixedSubspace_iff]202        intro n203        apply E.injective204        have h := congrArg205          (fun A : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ] K ↦206            A (E.symm y)) (hEsource (transportedFlag family i n))207        change E (selectedAtomicRepresentation (transportedFlag family i n)208          (E.symm y)) = sigma (transportedFlag family i n) (E (E.symm y)) at h209        calc210          E (selectedAtomicRepresentation (transportedFlag family i n) (E.symm y)) =211              sigma (transportedFlag family i n) (E (E.symm y)) := h212          _ = sigma (transportedFlag family i n) y := by rw [E.apply_symm_apply]213          _ = y := hy n214          _ = E (E.symm y) := (E.apply_symm_apply y).symm215    have hPintertwines :216        (E : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ] K).comp P₀ =217        P.comp (E : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ] K) := by218      apply ContinuousLinearMap.ext219      intro y220      rw [ContinuousLinearMap.comp_apply, ContinuousLinearMap.comp_apply,221        hP₀eq, hPeq]222      change E (F₀.starProjection y) = F.starProjection (E y)223      symm224      apply Submodule.eq_starProjection_of_mem_of_inner_eq_zero225      · rw [← hFmap]226        exact ⟨F₀.starProjection y,227          Submodule.starProjection_apply_mem F₀ y, rfl⟩228      · intro z hz229        rw [← hFmap] at hz230        obtain ⟨z₀, hz₀, rfl⟩ := hz231        rw [← E.map_sub]232        change inner ℂ (E (y - F₀.starProjection y)) (E z₀) = 0233        rw [E.inner_map_map]234        exact F₀.starProjection_inner_eq_zero y z₀ hz₀235    have hF₀span : F₀ =236        ℂ ∙ MathlibAnnex.CStarAlgebra.PureState.selectedEmbedding completedRootPureState i237          (MathlibAnnex.CStarAlgebra.PureState.selectedVector completedRootPureState i) := by238      rw [show F₀ = ⨅ n,239        (selectedAtomicRepresentation (transportedFlag family i n)).range by240          exact commonFixedSubspace_eq_iInf_range selectedAtomicRepresentation241            (transportedFlag family i) (isStarProjection_transportedFlag family i)]242      simpa [selectedAtomicRepresentation] using243        iInf_range_atomic_transportedFlag_eq_span family i244    have hRintertwines :245        (E : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ] K).comp R₀ =246        R.comp (E : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ] K) := by247      apply ContinuousLinearMap.ext248      intro y249      have hPmem : P₀ y ∈ F₀ := by250        rw [hP₀eq]251        exact commonFixedProjection_mem _ _252      rw [hF₀span] at hPmem253      obtain ⟨c, hc⟩ := Submodule.mem_span_singleton.mp hPmem254      have hleft : E (R₀ y) = c • eta_o := by255        rw [hR₀, ContinuousLinearMap.comp_apply, ← hc, map_smul,256          hLmap, map_smul, hEpoint, heta_root]257      have hPpoint : P (E y) = c • eta i := by258        have h := congrArg259          (fun A : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ] K ↦260            A y) hPintertwines261        change E (P₀ y) = P (E y) at h262        rw [← hc, map_smul, hEpoint] at h263        exact h.symm264      have hright : R (E y) = c • eta_o := by265        rw [hR, ContinuousLinearMap.comp_apply, hPpoint, map_smul]266        have hgen_i :267            (((Unitary.linearIsometryEquiv268              (representedGeneratorUnitary L hLunit rho i) : K ≃ₗᵢ[ℂ] K) :269                K →L[ℂ] K) (eta i)) = eta_o := heta_gen i270        rw [hgen_i]271      exact hleft.trans hright.symm272    have hsourceDecomp : L i = S₀ + R₀ := by273      simpa [rho₀] using hgenerator₀274    have htargetDecomp :275        rho (MathlibAnnex.CStarAlgebra.AtomicConstruction.generator selectedAtomicRepresentation L i) = S + R := by276      simpa using hgenerator277    have hSpoint : E (S₀ x) = S (E x) := by278      have h := congrArg279        (fun A : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ] K ↦280          A x) hSintertwines281      simpa [ContinuousLinearMap.comp_apply] using h282    have hRpoint : E (R₀ x) = R (E x) := by283      have h := congrArg284        (fun A : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ] K ↦285          A x) hRintertwines286      simpa [ContinuousLinearMap.comp_apply] using h287    calc288      E (L i x) = E ((S₀ + R₀) x) := by rw [hsourceDecomp]289      _ = E (S₀ x) + E (R₀ x) := by simp290      _ = S (E x) + R (E x) := by rw [hSpoint, hRpoint]291      _ = (S + R) (E x) := rfl292      _ = rho (MathlibAnnex.CStarAlgebra.AtomicConstruction.generator selectedAtomicRepresentation L i) (E x) := by293        rw [htargetDecomp]294  have hgeneratorAll (i : MathlibAnnex.CStarAlgebra.PureState.GNSClass Limit) :295      (E : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ] K).comp296          (L i) =297        (rho (MathlibAnnex.CStarAlgebra.AtomicConstruction.generator selectedAtomicRepresentation L i)).comp298          (E : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ] K) := by299    apply ContinuousLinearMap.ext300    intro x301    exact hsourceGenerator i x302  have hall := MathlibAnnex.CStarAlgebra.AtomicConstruction.intertwines_concreteTarget_of_generators303    selectedAtomicRepresentation L E rho hEsource hgeneratorAll a304  intro x305  have h := congrArg306    (fun A : MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ] K ↦307      A x) hall308  change E ((MathlibAnnex.CStarAlgebra.AtomicConstruction.ambientInclusion selectedAtomicRepresentation L a) x) =309    rho a (E x) at h310  exact h311312/-- Ordinary conditional endpoint: the actual completed-CAR construction313removes every representation-local shell, defect, and capture hypothesis.314Only the explicitly parameterized KOS statement remains. -/315theorem exists_completedAtomicTarget_uniqueIrreducibleModel316    (family : RepresentativeShellFamily) :317    ∃ L : MathlibAnnex.CStarAlgebra.PureState.GNSClass Limit →318        MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ]319          MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState,320      Representation.IsUniqueIrreducibleModel321        (MathlibAnnex.CStarAlgebra.AtomicConstruction.ambientInclusion selectedAtomicRepresentation L) := by322  obtain ⟨L, hLunit, hLmap, hLsource, hLroot, hsourceFaithful, hambientIrr⟩ :=323    exists_completedAtomicShellModel family324  refine ⟨L, ?_, hambientIrr, ?_⟩325  · exact MathlibAnnex.CStarAlgebra.AtomicConstruction.ambientInclusion_injective selectedAtomicRepresentation L326  · intro K _ _ _ rho hrho327    exact ambientInclusion_unitaryEquivalent328      family L hLunit hLmap hLsource hLroot rho hrho329330end MathlibAnnex.CStarAlgebra.CAR
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