The sharp weighted degree of a full standard-monomial prefix for an affine surface. The coefficient 2/3 of the square-root rank is retained, with an explicit linear error depending only on the equation degree.
theorem
CCDN.surface_standard_monomial_weight
{K : Type u_1}
[Field K]
(f : MvPolynomial (Fin 3) K)
(hf : f ≠ 0)
(hd : 0 < f.totalDegree)
{M : ℕ}
(hM : f.totalDegree ≤ M)
:
have S := standardMonomialPrefix (Ideal.span {f}) MonomialOrder.degLex M;
∑ a ∈ S, ↑(Finsupp.degree a) ≤ 2 / 3 * ↑S.card * √(2 * ↑S.card / ↑f.totalDegree) + (2 * ↑f.totalDegree + 2) * ↑S.card
Standard monomials up to degree M have weighted degree at most (2/3)s sqrt(2s/d)+(2d+2)s, where s is their cardinality and d is the surface equation degree.