theorem
proved
compose_left_id
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open lean source
IndisputableMonolith.Foundation.UniversalForcing.Strict.RichDomainCosts on GitHub at line 62.
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59 apply Subtype.ext
60 ring
61
62theorem compose_left_id (a : FrequencyRatio) :
63 strictMusicRealization.compose strictMusicRealization.one a = a := by
64 show (⟨1 * a.1, _⟩ : FrequencyRatio) = a
65 apply Subtype.ext
66 simp
67
68end MusicRich
69
70/-! ## Biology -/
71
72namespace BiologyRich
73
74open Biology
75
76theorem lineageCost_zero_iff (a b : LineageState) :
77 lineageCost a b = 0 ↔ a = b := by
78 unfold lineageCost
79 by_cases h : a = b
80 · simp [h]
81 · simp [h]
82
83def lineageCost_decidable (a b : LineageState) : Decidable (a = b) :=
84 inferInstance
85
86theorem reproduce_assoc (a b c : LineageState) :
87 reproduce (reproduce a b) c = reproduce a (reproduce b c) := by
88 unfold reproduce
89 congr 1
90 exact Nat.add_assoc _ _ _
91
92theorem reproduce_left_id (a : LineageState) :