theorem cesHessianQF_on_one (_hJ : 0 < J) (ρ c : ℝ) (_hc : 0 < c) (α : ℝ) :
cesHessianQF J ρ c (fun _ => α) = 0 := by
simp only [cesHessianQF]
rw [Finset.sum_const, Finset.sum_const, Finset.card_univ, Fintype.card_fin]
ringGradient and Hessian of CES at the symmetric point.