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MathlibAnnex/Analysis/CStarAlgebra/CAR/CaptureSurviving.lean

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1import MathlibAnnex.Analysis.CStarAlgebra.CAR.CaptureZero2import Mathlib.Analysis.Normed.Module.Normalize34/-!5# Vectors carried by a surviving completed-CAR defect67The target-side unitary-completion relation transports a normalized vector8from a nonzero initial limiting fixed space to the root limiting fixed space.9The actual completed-CAR compression estimates then identify both vector10states.  No ambient rank-one assertion is made for an arbitrary target11representation.12-/1314set_option autoImplicit false15set_option maxHeartbeats 12000001617noncomputable section1819open Filter Topology20open scoped ComplexOrder ENNReal lp InnerProduct2122namespace MathlibAnnex.CStarAlgebra.CAR2324open MathlibAnnex.Analysis.CStarAlgebra25open MathlibAnnex.Analysis.InnerProductSpace2627universe v2829/-- A specified nonzero limiting fixed space supplies unit vectors carrying30the selected state and the root state, joined by the represented target31generator. -/32theorem exists_targetDefectVectors_of_fixedSpace_ne_bot33    (family : RepresentativeShellFamily)34    (L : MathlibAnnex.CStarAlgebra.PureState.GNSClass Limit →35      MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ]36        MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState)37    (hLunit : ∀ i, L i ∈ unitary38      (MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ]39        MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState))40    (hLsource : ∀ i n, (L i).comp (selectedAtomicRepresentation41      (transportedFlag family i n - transportedFlag family i (n + 1))) =42        representedShellLink family i n)43    {K : Type v} [NormedAddCommGroup K] [InnerProductSpace ℂ K]44    [CompleteSpace K] (rho : Representation (AtomicTarget L) K)45    (i : MathlibAnnex.CStarAlgebra.PureState.GNSClass Limit)46    (hi : (⨅ n, ((restrictedRepresentation L rho)47      (transportedFlag family i n)).range) ≠ ⊥) :48    ∃ eta_i eta_o : K,49      ‖eta_i‖ = 1 ∧ ‖eta_o‖ = 1 ∧50      (∀ n, (restrictedRepresentation L rho)51        (transportedFlag family i n) eta_i = eta_i) ∧52      (∀ n, (restrictedRepresentation L rho) (rootFlag n) eta_o = eta_o) ∧53      (Unitary.linearIsometryEquiv54        (representedGeneratorUnitary L hLunit rho i) : K ≃ₗᵢ[ℂ] K) eta_i = eta_o ∧55      Representation.vectorFunctional (restrictedRepresentation L rho) eta_i =56        (MathlibAnnex.CStarAlgebra.PureState.representative completedRootPureState i).1 ∧57      Representation.vectorFunctional (restrictedRepresentation L rho) eta_o =58        rootState := by59  let sigma := restrictedRepresentation L rho60  let U : ℕ → Submodule ℂ K := fun n ↦61    (sigma (transportedFlag family i n)).range62  let V : ℕ → Submodule ℂ K := fun n ↦ (sigma (rootFlag n)).range63  obtain ⟨S, T, P, Q, R, -, -, -, -, -, -, hPrange, -, hQrange, -, -, -, -,64      -, -, -, htransport⟩ :=65    exists_targetShellReconstruction family L hLunit hLsource rho i66  have hU_ne : (⨅ n, U n) ≠ ⊥ := by67    simpa [U, sigma] using hi68  obtain ⟨x, hxU, hxne⟩ := Submodule.exists_mem_ne_zero_of_ne_bot hU_ne69  let eta_i : K := NormedSpace.normalize x70  have heta_i_norm : ‖eta_i‖ = 1 := NormedSpace.norm_normalize hxne71  have heta_i_mem : eta_i ∈ ⨅ n, U n := by72    change NormedSpace.normalize x ∈ ⨅ n, U n73    rw [NormedSpace.normalize]74    exact (⨅ n, U n).smul_mem (‖x‖⁻¹ : ℝ) hxU75  let e : K ≃ₗᵢ[ℂ] K := Unitary.linearIsometryEquiv76    (representedGeneratorUnitary L hLunit rho i)77  let eta_o : K := e eta_i78  have heta_o_norm : ‖eta_o‖ = 1 := by79    rw [show ‖eta_o‖ = ‖eta_i‖ by exact e.norm_map eta_i]80    exact heta_i_norm81  have heta_o_mem : eta_o ∈ ⨅ n, V n := by82    exact (htransport eta_i).1 heta_i_mem83  have heta_i_fixed (n : ℕ) :84      sigma (transportedFlag family i n) eta_i = eta_i := by85    have hn : eta_i ∈ U n := (Submodule.mem_iInf U).mp heta_i_mem n86    exact LinearMap.IsIdempotentElem.mem_range_iff87      (ContinuousLinearMap.IsIdempotentElem.toLinearMap88        (IsStarProjection.map_representation sigma89          (isStarProjection_transportedFlag family i n)).isIdempotentElem) |>.mp hn90  have heta_o_fixed (n : ℕ) : sigma (rootFlag n) eta_o = eta_o := by91    have hn : eta_o ∈ V n := (Submodule.mem_iInf V).mp heta_o_mem n92    exact LinearMap.IsIdempotentElem.mem_range_iff93      (ContinuousLinearMap.IsIdempotentElem.toLinearMap94        (IsStarProjection.map_representation sigma95          (isStarProjection_rootFlag n)).isIdempotentElem) |>.mp hn96  have heta_i_state : Representation.vectorFunctional sigma eta_i =97      (MathlibAnnex.CStarAlgebra.PureState.representative completedRootPureState i).1 := by98    apply ContinuousLinearMap.ext99    intro b100    have hcoeff := inner_map_eq_of_compression_tendsto sigma101      (Representation.continuousLinearMap sigma).continuous102      (transportedFlag family i)103      (MathlibAnnex.CStarAlgebra.PureState.representative completedRootPureState i).1 b eta_i eta_i104      (fun n ↦ (isStarProjection_transportedFlag family i n).isSelfAdjoint.star_eq)105      heta_i_fixed heta_i_fixed106      (tendsto_representative_transported_compression family i b)107    have hself : inner ℂ eta_i eta_i = 1 := by108      rw [inner_self_eq_norm_sq_to_K, heta_i_norm]109      norm_num110    change inner ℂ eta_i (sigma b eta_i) =111      (MathlibAnnex.CStarAlgebra.PureState.representative completedRootPureState i).1 b112    calc113      inner ℂ eta_i (sigma b eta_i) =114          (MathlibAnnex.CStarAlgebra.PureState.representative completedRootPureState i).1 b *115            inner ℂ eta_i eta_i := hcoeff116      _ = (MathlibAnnex.CStarAlgebra.PureState.representative completedRootPureState i).1 b := by117        rw [hself, mul_one]118  have heta_o_state : Representation.vectorFunctional sigma eta_o = rootState := by119    apply ContinuousLinearMap.ext120    intro b121    have hcompression : Tendsto122        (fun n ↦ rootFlag n * b * rootFlag n - rootState b • rootFlag n)123        atTop (nhds 0) := by124      simpa using tendsto_transported_compressionError125        (StarAlgEquiv.refl ℂ Limit) rootState (fun _ ↦ rfl) b126    have hcoeff := inner_map_eq_of_compression_tendsto sigma127      (Representation.continuousLinearMap sigma).continuous rootFlag rootState128      b eta_o eta_o129      (fun n ↦ (isStarProjection_rootFlag n).isSelfAdjoint.star_eq)130      heta_o_fixed heta_o_fixed hcompression131    have hself : inner ℂ eta_o eta_o = 1 := by132      rw [inner_self_eq_norm_sq_to_K, heta_o_norm]133      norm_num134    change inner ℂ eta_o (sigma b eta_o) = rootState b135    calc136      inner ℂ eta_o (sigma b eta_o) =137          rootState b * inner ℂ eta_o eta_o := hcoeff138      _ = rootState b := by rw [hself, mul_one]139  exact ⟨eta_i, eta_o, heta_i_norm, heta_o_norm,140    heta_i_fixed, heta_o_fixed, rfl, heta_i_state, heta_o_state⟩141142/-- Every irreducible target representation contains a transported pair of143unit defect vectors with the exact selected and root completed-CAR states. -/144theorem exists_targetDefectVectors145    (family : RepresentativeShellFamily)146    (L : MathlibAnnex.CStarAlgebra.PureState.GNSClass Limit →147      MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ]148        MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState)149    (hLunit : ∀ i, L i ∈ unitary150      (MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ]151        MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState))152    (hLsource : ∀ i n, (L i).comp (selectedAtomicRepresentation153      (transportedFlag family i n - transportedFlag family i (n + 1))) =154        representedShellLink family i n)155    {K : Type v} [NormedAddCommGroup K] [InnerProductSpace ℂ K]156    [CompleteSpace K] (rho : Representation (AtomicTarget L) K)157    (hrho : rho.IsIrreducible) :158    ∃ (i : MathlibAnnex.CStarAlgebra.PureState.GNSClass Limit) (eta_i eta_o : K),159      ‖eta_i‖ = 1 ∧ ‖eta_o‖ = 1 ∧160      (∀ n, (restrictedRepresentation L rho)161        (transportedFlag family i n) eta_i = eta_i) ∧162      (∀ n, (restrictedRepresentation L rho) (rootFlag n) eta_o = eta_o) ∧163      (Unitary.linearIsometryEquiv164        (representedGeneratorUnitary L hLunit rho i) : K ≃ₗᵢ[ℂ] K) eta_i = eta_o ∧165      Representation.vectorFunctional (restrictedRepresentation L rho) eta_i =166        (MathlibAnnex.CStarAlgebra.PureState.representative completedRootPureState i).1 ∧167      Representation.vectorFunctional (restrictedRepresentation L rho) eta_o =168        rootState := by169  obtain ⟨i, hi⟩ := exists_nonzero_targetFixedSpace170    family L hLunit hLsource rho hrho171  obtain ⟨eta_i, eta_o, h⟩ :=172    exists_targetDefectVectors_of_fixedSpace_ne_bot173      family L hLunit hLsource rho i hi174  exact ⟨i, eta_i, eta_o, h⟩175176/-- A surviving defect yields one common root unit vector and a compatible177unit defect vector for every selected pure-state class.  Each represented178generator sends its selected vector to the same root vector, and every vector179state is identified from the actual completed-CAR compression theorem. -/180theorem exists_targetDefectVectorFamily181    (family : RepresentativeShellFamily)182    (L : MathlibAnnex.CStarAlgebra.PureState.GNSClass Limit →183      MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ]184        MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState)185    (hLunit : ∀ i, L i ∈ unitary186      (MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState →L[ℂ]187        MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState))188    (hLsource : ∀ i n, (L i).comp (selectedAtomicRepresentation189      (transportedFlag family i n - transportedFlag family i (n + 1))) =190        representedShellLink family i n)191    {K : Type v} [NormedAddCommGroup K] [InnerProductSpace ℂ K]192    [CompleteSpace K] (rho : Representation (AtomicTarget L) K)193    (hrho : rho.IsIrreducible) :194    ∃ (eta_o : K) (eta : MathlibAnnex.CStarAlgebra.PureState.GNSClass Limit → K),195      ‖eta_o‖ = 1 ∧196      (∀ n, (restrictedRepresentation L rho) (rootFlag n) eta_o = eta_o) ∧197      Representation.vectorFunctional (restrictedRepresentation L rho) eta_o =198        rootState ∧199      ∀ i,200        ‖eta i‖ = 1 ∧201        (∀ n, (restrictedRepresentation L rho)202          (transportedFlag family i n) (eta i) = eta i) ∧203        (Unitary.linearIsometryEquiv204          (representedGeneratorUnitary L hLunit rho i) : K ≃ₗᵢ[ℂ] K) (eta i) =205            eta_o ∧206        Representation.vectorFunctional (restrictedRepresentation L rho) (eta i) =207          (MathlibAnnex.CStarAlgebra.PureState.representative completedRootPureState i).1 := by208  obtain ⟨i₀, eta₀, eta_o, -, heta_o_norm, -, heta_o_fixed, -, -,209      heta_o_state⟩ :=210    exists_targetDefectVectors family L hLunit hLsource rho hrho211  let sigma := restrictedRepresentation L rho212  have heta_o_mem : eta_o ∈213      (⨅ n, (sigma (rootFlag n)).range) := by214    rw [Submodule.mem_iInf]215    intro n216    exact ⟨eta_o, heta_o_fixed n⟩217  let e (i : MathlibAnnex.CStarAlgebra.PureState.GNSClass Limit) : K ≃ₗᵢ[ℂ] K :=218    Unitary.linearIsometryEquiv219      (representedGeneratorUnitary L hLunit rho i)220  let eta (i : MathlibAnnex.CStarAlgebra.PureState.GNSClass Limit) : K := (e i).symm eta_o221  refine ⟨eta_o, eta, heta_o_norm, heta_o_fixed, heta_o_state, ?_⟩222  intro i223  have heta_norm : ‖eta i‖ = 1 := by224    rw [show ‖eta i‖ = ‖eta_o‖ by exact (e i).symm.norm_map eta_o]225    exact heta_o_norm226  obtain ⟨S, T, P, Q, R, -, -, -, -, -, -, -, -, -, -, -, -, -, -, -, -,227      htransport⟩ :=228    exists_targetShellReconstruction family L hLunit hLsource rho i229  have heta_mem : eta i ∈230      (⨅ n, (sigma (transportedFlag family i n)).range) := by231    apply (htransport (eta i)).2232    simpa [e, eta] using heta_o_mem233  have heta_fixed (n : ℕ) :234      sigma (transportedFlag family i n) (eta i) = eta i := by235    have hn : eta i ∈ (sigma (transportedFlag family i n)).range :=236      (Submodule.mem_iInf _).mp heta_mem n237    exact LinearMap.IsIdempotentElem.mem_range_iff238      (ContinuousLinearMap.IsIdempotentElem.toLinearMap239        (IsStarProjection.map_representation sigma240          (isStarProjection_transportedFlag family i n)).isIdempotentElem) |>.mp hn241  have heta_state : Representation.vectorFunctional sigma (eta i) =242      (MathlibAnnex.CStarAlgebra.PureState.representative completedRootPureState i).1 := by243    apply vectorFunctional_eq_of_compression_tendsto sigma244      (transportedFlag family i)245      (MathlibAnnex.CStarAlgebra.PureState.representative completedRootPureState i).1246      (fun n ↦ (isStarProjection_transportedFlag family i n).isSelfAdjoint.star_eq)247      (tendsto_representative_transported_compression family i)248      (eta i) heta_norm heta_fixed249  refine ⟨heta_norm, heta_fixed, ?_, heta_state⟩250  simp [e, eta]251252end MathlibAnnex.CStarAlgebra.CAR
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