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phi
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IndisputableMonolith.Information.RecognitionEntropy on GitHub at line 25.
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22namespace IndisputableMonolith.Information.RecognitionEntropy
23
24/-- The golden ratio (local definition for self-containment). -/
25noncomputable def phi : ℝ := (1 + Real.sqrt 5) / 2
26
27/-- phi > 1 (needed for log base phi). -/
28theorem phi_gt_one : phi > 1 := by
29 unfold phi
30 have h5 : Real.sqrt 5 > 1 := by
31 rw [show (1 : ℝ) = Real.sqrt 1 from (Real.sqrt_one).symm]
32 exact Real.sqrt_lt_sqrt (by norm_num) (by norm_num)
33 linarith
34
35/-- A phi-bit: the amount of information in a binary choice
36 with phi-weighted branches. -/
37noncomputable def phiBit : ℝ := 1 / Real.log phi
38
39/-- Recognition entropy: H_R(p) = -sum p_i * log_phi(p_i).
40 This is Shannon entropy but in base phi instead of base 2. -/
41noncomputable def recognitionEntropy (probs : List ℝ) : ℝ :=
42 -(probs.map fun p => if p > 0 then p * (Real.log p / Real.log phi) else 0).sum
43
44/-- The CP6 meaning manifold has 12 real dimensions.
45 In phi-bits, the capacity at resolution epsilon is
46 phi^12 * log_phi(1/epsilon) ≈ phi^12 ≈ 321.997. -/
47noncomputable def cp6CapacityPhiBits : ℝ := phi ^ 12
48
49/-- phi^12 > 2^12 = 4096... actually phi^12 ≈ 322, which is less than 4096.
50 The correct comparison: log_phi of the capacity exceeds log_2 because
51 phi < 2, so each phi-bit carries MORE discrimination. -/
52theorem phi_lt_two : phi < 2 := by
53 unfold phi
54 have h5 : Real.sqrt 5 < 3 := by
55 rw [show (3 : ℝ) = Real.sqrt 9 from by rw [show (9:ℝ) = 3^2 from by norm_num, Real.sqrt_sq (by norm_num : (3:ℝ) ≥ 0)]]