theorem margin_strict_in_Tstar {T Tstar1 Tstar2 : ℝ}
(hTs1 : 0 < Tstar1) (hTs2 : 0 < Tstar2)
(h : Tstar1 < Tstar2) (hT : 0 < T)
(hTlt : T < Tstar1) :
institutionalMargin T Tstar1 < institutionalMargin T Tstar2 := by
simp only [institutionalMargin]
-- Both margins are positive (T < T*₁ < T*₂)
have hm1 : 0 < 1 - T / Tstar1 := by
rw [sub_pos, div_lt_one hTs1]; exact hTlt
have hm2 : 0 < 1 - T / Tstar2 := by
rw [sub_pos, div_lt_one hTs2]; linarith
rw [max_eq_right (le_of_lt hm1), max_eq_right (le_of_lt hm2)]
-- Goal: 1 - T / Tstar1 < 1 - T / Tstar2
-- Suffices: T / Tstar2 < T / Tstar1
suffices T / Tstar2 < T / Tstar1 by linarith
rw [div_lt_div_iff₀ hTs2 hTs1]
exact mul_lt_mul_of_pos_left h hTInstitutional Reform Equivalence, Adjustment Timescale, and Fragility Ordering