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subdivisionLevels
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IndisputableMonolith.MusicTheory.Rhythm on GitHub at line 85.
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82Binary subdivision (halving) maps directly to the factor-of-2 structure
83in the 8-tick cycle. -/
84
85def subdivisionLevels : List ℕ := [1, 2, 4, 8]
86
87theorem subdivision_is_binary :
88 subdivisionLevels = [2^0, 2^1, 2^2, 2^3] := by
89 simp [subdivisionLevels]
90
91/-! ## Swing as Asymmetry
92
93"Swing" in jazz/blues displaces the second note of each pair.
94A 2:1 swing ratio means the first eighth note lasts twice as long
95as the second — introducing a φ-like asymmetry into the rhythm. -/
96
97noncomputable def swingRatio_triplet : ℝ := 2
98noncomputable def swingRatio_moderate : ℝ := 3 / 2
99
100theorem swing_triplet_is_octave_ratio :
101 swingRatio_triplet = 2 := rfl
102
103theorem swing_moderate_is_fifth :
104 swingRatio_moderate = 3 / 2 := rfl
105
106end IndisputableMonolith.MusicTheory.Rhythm