theorem revenue_equivalence {τ W : ℝ} {N : ℕ} (hN : 0 < N) :
recipientTaxRevenue τ W N = estateTaxRevenue τ W := by
simp only [recipientTaxRevenue, estateTaxRevenue, perHeirWealth]
have hNne : (↑N : ℝ) ≠ 0 := Nat.cast_ne_zero.mpr (by omega)
field_simpFair Inheritance: Taxing Concentration, Not Transfer