Determinant nondegeneracy turns multiplication bounds on a hyperplane complement into the product inequality used to control the largest successive minimum. This file contains the algebraic product step.
theorem
CCDN.hyperplane_multiplication_minimum_product
{F : Type u_1}
{K : Type u_2}
[Field F]
[Field K]
[Algebra F K]
{ι : Type u_3}
[Fintype ι]
(ℓ μ : K →ₗ[F] F)
(hℓ : ℓ ≠ 0)
(hℓ1 : ℓ 1 = 0)
(hμ1 : μ 1 = 1)
(b : Module.Basis ι F ↥(hyperplaneComplement ℓ μ))
(w : ι → ℝ)
{M : ℝ}
(hM : 0 ≤ M)
(hw : ∀ (i j : ι), ℓ (↑(b i) * ↑(b j)) ≠ 0 → M ≤ w i * w j)
:
Let ℓ ≠ 0 and μ be linear functionals on K with ℓ 1 = 0 and μ 1 = 1, and let b be a
basis of hyperplaneComplement ℓ μ with weights w. If M ≤ w i * w j whenever
ℓ (b i * b j) ≠ 0, then M ^ (d + 2) ≤ (M * ∏ i, w i) ^ 2, where d is the size of the basis.