Positioning a scaled homogeneous model while retaining a coefficient bound for the original affine equation and the full scaling gain in its height.
A monotone scaled logarithmic-height ratio. A lower bound for the scaled model height yields the saving needed to change the box exponent 2/d to 1/d.
theorem
CCDN.exists_scaled_model_position
(f : MvPolynomial (Fin 2) ℤ)
(hf0 : f ≠ 0)
(hd : 0 < f.totalDegree)
{h : ℤ}
(hh : 1 ≤ h)
:
∃ (a : Fin 2 → ℤ) (H : ℝ),
(∀ (j : Fin 2), 0 ≤ a j ∧ a j ≤ ↑f.totalDegree) ∧ 1 ≤ H ∧ ↑h ^ f.totalDegree ≤ H ∧ CoefficientHeightLE f H ∧ Real.log
|↑(MonomialOrder.lex.leadingCoeff
((homogeneousTranslation ℤ a) (scaledHomogenize f.totalDegree h f)))| ≤ Real.log H ∧ Real.log H ≤ Real.log
|↑(MonomialOrder.lex.leadingCoeff
((homogeneousTranslation ℤ a) (scaledHomogenize f.totalDegree h f)))| + 14 * ↑f.totalDegree ^ 2
The model height is at least h^d and also bounds every original affine coefficient, even after leading-coefficient positioning of the scaled model.