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mu_codata
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IndisputableMonolith.Masses.MuRatioScoreCard on GitHub at line 44.
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41/-! ## CODATA reference value -/
42
43/-- CODATA 2022 proton-electron mass ratio. -/
44def mu_codata : ℝ := 1836.15267343
45
46/-! ## Predicted ratio -/
47
48/-- Predicted dimensionless ratio from the φ-ladder. -/
49noncomputable def mu_pred : ℝ := proton_binding_pred / electron_pred
50
51private lemma electron_pred_pos : 0 < electron_pred := by
52 have hb := electron_mass_bounds
53 linarith [hb.1]
54
55private lemma proton_pred_pos : 0 < proton_binding_pred := by
56 have hb := proton_mass_bounds
57 linarith [hb.1]
58
59theorem mu_pred_pos : 0 < mu_pred :=
60 div_pos proton_pred_pos electron_pred_pos
61
62/-! ## Predicted ratio bracket
63
64We prove `1898 < μ_pred < 1904`. The proof strategy: multiply through
65by `electron_pred` (positive) to convert ratio bounds into
66multiplicative bounds, then apply the two mass-bound theorems plus
67arithmetic.
68-/
69
70theorem mu_pred_lower : (1898 : ℝ) < mu_pred := by
71 unfold mu_pred
72 have he_pos : 0 < electron_pred := electron_pred_pos
73 rw [lt_div_iff₀ he_pos]
74 -- want: 1898 * electron_pred < proton_binding_pred