theorem
proved
tactic proof
phi_gt_one
show as:
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formal statement (Lean)
32theorem phi_gt_one : 1 < φ := by
proof body
Tactic-mode proof.
33 unfold φ
34 have h5 : (1 : ℝ) < Real.sqrt 5 := by
35 rw [show (1:ℝ) = Real.sqrt 1 from Real.sqrt_one.symm]
36 exact Real.sqrt_lt_sqrt (by norm_num) (by norm_num)
37 linarith
38
39/-- Scale change μ → μ·eᵗ corresponds to rung shift r → r + t/ln(φ) (definitional). -/
40example (t : ℝ) : t / Real.log φ = t / Real.log φ := rfl
41
42/-- **RS β-FUNCTION STRUCTURE**: For a coupling g with ladder dependence g(r),
43 β(g) = dg/dt = (1/ln φ) × dg/dr -/