theorem
proved
pillar2_composite_refines
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IndisputableMonolith.RecogGeom.Foundations on GitHub at line 70.
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All declarations in this module, on Recognition.
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depends on
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has -
ConfigSpace -
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neighborhood -
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Resolution -
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ConfigSpace -
Resolution -
Resolution -
quotientMapLeft -
quotientMapRight -
refinement_theorem -
ConfigSpace -
EventSpace
used by
formal source
67 composite_info_monotone_left r₁ r₂ h
68
69/-- **Corollary**: The composite quotient refines both component quotients. -/
70theorem pillar2_composite_refines {C E₁ E₂ : Type*}
71 [ConfigSpace C] [EventSpace E₁] [EventSpace E₂]
72 (r₁ : Recognizer C E₁) (r₂ : Recognizer C E₂) :
73 Function.Surjective (quotientMapLeft r₁ r₂) ∧
74 Function.Surjective (quotientMapRight r₁ r₂) :=
75 refinement_theorem r₁ r₂
76
77/-! ## Pillar 3: Finite Resolution is Fundamental -/
78
79/-- **Pillar 3 (Finite Resolution Obstruction)**: If a neighborhood has
80 infinitely many configurations but only finitely many events,
81 no injection exists. -/
82theorem pillar3_finite_resolution_obstruction {C E : Type*}
83 [ConfigSpace C] [EventSpace E]
84 (L : LocalConfigSpace C) (r : Recognizer C E)
85 (c : C) (U : Set C) (hU : U ∈ L.N c)
86 (hinf : Set.Infinite U) (hfin : (r.R '' U).Finite) :
87 ¬Function.Injective (r.R ∘ Subtype.val : U → E) :=
88 no_injection_on_infinite_finite L r c U hU hinf hfin
89
90/-! ## The Fundamental Theorem -/
91
92/-- **FUNDAMENTAL THEOREM OF RECOGNITION GEOMETRY**
93
94 Two configurations are in the same equivalence class if and only if
95 the recognizer assigns them the same event.
96
97 This is the cornerstone: observable space = C / {same events}. -/
98theorem fundamental_theorem {C E : Type*} [ConfigSpace C] [EventSpace E]
99 (r : Recognizer C E) (c₁ c₂ : C) :
100 recognitionQuotientMk r c₁ = recognitionQuotientMk r c₂ ↔ r.R c₁ = r.R c₂ :=