theorem
proved
tactic proof
N_galactic_approx
show as:
view Lean formalization →
formal statement (Lean)
30theorem N_galactic_approx : 140 < N_galactic ∧ N_galactic < 145 := by
proof body
Tactic-mode proof.
31 have h_ratio_val : tau_star_s / tau0_SI = (galactic_ratio_rational : ℝ) := by
32 unfold tau_star_s tau0_SI galactic_ratio_rational
33 norm_num
34 have hlog_phi : 0 < Real.log phi := Real.log_pos Constants.one_lt_phi
35
36 constructor
37 · unfold N_galactic
38 rw [h_ratio_val]
39 apply (lt_div_iff₀ hlog_phi).mpr
40 rw [← Real.log_rpow Constants.phi_pos]
41 apply Real.log_lt_log (Real.rpow_pos_of_pos Constants.phi_pos 140)
42 exact phi_pow_140_lt_ratio
43 · unfold N_galactic
44 rw [h_ratio_val]
45 apply (div_lt_iff₀ hlog_phi).mpr
46 rw [← Real.log_rpow Constants.phi_pos]
47 apply Real.log_lt_log
48 · have h_pos : (0 : ℝ) < (galactic_ratio_rational : ℝ) := by norm_num [galactic_ratio_rational]
49 exact h_pos
50 · exact ratio_lt_phi_pow_145
51
52/-- **THEOREM: τ★ Lies on the φ-Ladder** -/