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MathlibAnnex.CStarAlgebra.CAR.atomicCounterexampleEndpoint

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Exact declaration: MathlibAnnex.CStarAlgebra.CAR.atomicCounterexampleEndpoint

MathlibAnnex/Analysis/CStarAlgebra/CAR/AtomicCounterexample.lean · lines 95–98

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1import MathlibAnnex.Analysis.CStarAlgebra.CAR.GlobalTransport
2import MathlibAnnex.Analysis.CStarAlgebra.CAR.AtomicEndpoint
3
4/-!
5# Ordinary Naimark endpoint from the proved CAR homogeneity theorem
6
7The shell family and concrete target in this file are chosen once.  The
8generic `MathlibAnnex.CStarAlgebra.KishimotoOzawaSakaiProperty` is not changed or assumed: the closed CAR theorem
9supplies exactly the representative-to-root automorphisms needed by the
10family-parametric atomic construction.
11-/
12
13set_option autoImplicit false
14
15noncomputable section
16
17namespace MathlibAnnex.CStarAlgebra.CAR
18
19open MathlibAnnex.Analysis.CStarAlgebra
20
21universe v
22
23/-- Canonical identity shell data at the distinguished root class. -/
24private noncomputable def rootRepresentativeShellData :
25    RepresentativeShellData completedRootPureState.classOf where
26  alpha := StarAlgEquiv.refl ℂ Limit
27  state_eq := rootShell_identity_family.1
28  link := rootShell
29  initial_support := fun n ↦ (rootShell_identity_family.2 n).1
30  final_support := fun n ↦ (rootShell_identity_family.2 n).2
31
32/-- For one selected pure-state class, closed CAR homogeneity supplies a
33single automorphism.  Generic approximate-inner shell matching then supplies
34all exact shell links for that same automorphism.  The root branch is fixed
35canonically instead of invoking homogeneity. -/
36noncomputable def representativeShellDataOfHomogeneity
37    (j : MathlibAnnex.CStarAlgebra.PureState.GNSClass Limit) : RepresentativeShellData j := by
38  classical
39  by_cases hj : j = completedRootPureState.classOf
40  · subst j
41    exact rootRepresentativeShellData
42  · let hex := homogeneity
43      (MathlibAnnex.CStarAlgebra.PureState.representative completedRootPureState j).1
44      completedRootPureState.1
45      (MathlibAnnex.CStarAlgebra.PureState.representative completedRootPureState j).2
46      completedRootPureState.2
47    let alpha := Classical.choose hex
48    have halpha := Classical.choose_spec hex
49    let hwex := MathlibAnnex.CStarAlgebra.exists_shell_family_of_approximately_inner
50      Limit alpha halpha.2 rootShell isStarProjection_rootShell
51    let w := Classical.choose hwex
52    have hw := Classical.choose_spec hwex
53    exact
54      { alpha := alpha
55        state_eq := halpha.1
56        link := w
57        initial_support := fun n ↦ (hw n).1
58        final_support := fun n ↦ (hw n).2 }
59
60@[simp]
61theorem representativeShellDataOfHomogeneity_root_alpha :
62    (representativeShellDataOfHomogeneity
63      completedRootPureState.classOf).alpha = StarAlgEquiv.refl ℂ Limit := by
64  simp [representativeShellDataOfHomogeneity, rootRepresentativeShellData]
65
66@[simp]
67theorem representativeShellDataOfHomogeneity_root_link (n : ℕ) :
68    (representativeShellDataOfHomogeneity
69      completedRootPureState.classOf).link n = rootShell n := by
70  simp [representativeShellDataOfHomogeneity, rootRepresentativeShellData]
71
72/-- The one representative shell family used by the ordinary CAR endpoint. -/
73noncomputable def homogeneityShellFamily : RepresentativeShellFamily where
74  data := representativeShellDataOfHomogeneity
75  root_alpha := representativeShellDataOfHomogeneity_root_alpha
76  root_link := representativeShellDataOfHomogeneity_root_link
77
78/-- The single concrete C-star algebra used by every field of `AtomicCounterexampleEndpoint`. -/
79abbrev AtomicCounterexampleAlgebra := ShellFamilyTarget homogeneityShellFamily
80
81/-- The actual completed CAR source map into the fixed main target. -/
82noncomputable def atomicCounterexampleSourceHom : Limit →⋆ₐ[ℂ] AtomicCounterexampleAlgebra :=
83  shellFamilySourceHom homogeneityShellFamily
84
85/-- The fixed faithful irreducible displayed representation of `AtomicCounterexampleAlgebra`. -/
86noncomputable def atomicCounterexampleRepresentation :
87    Representation AtomicCounterexampleAlgebra
88      (MathlibAnnex.CStarAlgebra.PureState.SelectedAtomicHilbert completedRootPureState) :=
89  shellFamilyInclusion homogeneityShellFamily
90
91/-- Fully expanded ordinary endpoint for the single target chosen above. -/
92abbrev AtomicCounterexampleEndpoint : Prop :=
93  ShellFamilyEndpoint.{v} homogeneityShellFamily
94
95/-- Closed ordinary Naimark main for the actual CAR construction.  It has no
96generic KOS, shell-data, rank-one, capture, simplicity, or compactness premise. -/
97theorem atomicCounterexampleEndpoint : AtomicCounterexampleEndpoint.{v} :=
98  shellFamilyEndpoint homogeneityShellFamily
99
100end MathlibAnnex.CStarAlgebra.CAR