A uniform short-sum bound from polynomial-value growth #
This form keeps the analytic scale independent of the location of the integer interval. All constants are chosen before the polynomial system; only the upper-bound constant depends on its restricted discriminant.
theorem
NairTenenbaum.exists_integerSum_mainTerm_bound
{g : ℕ}
(hg : 0 < g)
{A B ε σ c : ℝ}
(hA : 1 ≤ A)
(hB : 1 ≤ B)
(hε : 0 < ε)
(hsmall : ↑g ^ 2 * ε ≤ 1 / 8)
(hσ : 0 < σ)
(hσsmall : ↑g ^ 2 * σ ≤ 1 / 8)
(hc : 0 ≤ c)
(hmargin : c * σ ≤ 17 * ↑g * ε / 24)
:
∃ (x₀ : ℝ),
1 < x₀ ∧ ∃ (C : ℕ → ℝ),
(∀ (D : ℕ), 0 < C D) ∧ ∀ (k r : ℕ) (P : PolynomialSystem k r),
P.total.natDegree = g →
∀ (F : ArithmeticMap k),
Admissible A B σ F →
∀ (x y : ℝ) (a b : ℤ),
x₀ ≤ x →
x ^ (4 * ↑g ^ 2 * ε) ≤ y →
a ≤ b →
y / 2 ≤ ↑b - ↑a →
↑b - ↑a ≤ 2 * y →
(∀ t ∈ Finset.Ioc a b, ↑(Polynomial.eval t P.total).natAbs ≤ x ^ c) →
P.integerSum F a b ≤ C P.badDiscriminant * mainTerm P F x y
Short sums over arbitrary integer intervals, assuming a bound on the actual polynomial values and a positive margin between arithmetic growth and the exceptional-set saving.
theorem
NairTenenbaum.PolynomialSystem.integerSum_le_of_value_bound
{k r : ℕ}
(P : PolynomialSystem k r)
{A B σ c x y : ℝ}
{F : ArithmeticMap k}
(hF : Admissible A B σ F)
(hB : 0 ≤ B)
(hσ : 0 ≤ σ)
(hx : 0 ≤ x)
{a b : ℤ}
(hab : a ≤ b)
(hlen : ↑b - ↑a ≤ 2 * y)
(hvalue : ∀ t ∈ Finset.Ioc a b, ↑(Polynomial.eval t P.total).natAbs ≤ x ^ c)
:
The elementary bound used on a bounded range of the analytic scale.
theorem
NairTenenbaum.exists_integerSum_mainTerm_bound_all_scales
{g : ℕ}
(hg : 0 < g)
{A B ε σ c : ℝ}
(hA : 1 ≤ A)
(hB : 1 ≤ B)
(hε : 0 < ε)
(hsmall : ↑g ^ 2 * ε ≤ 1 / 8)
(hσ : 0 < σ)
(hσsmall : ↑g ^ 2 * σ ≤ 1 / 8)
(hc : 0 ≤ c)
(hmargin : c * σ ≤ 17 * ↑g * ε / 24)
:
∃ (C : ℕ → ℝ),
(∀ (D : ℕ), 0 < C D) ∧ ∀ (k r : ℕ) (P : PolynomialSystem k r),
P.total.natDegree = g →
∀ (F : ArithmeticMap k),
Admissible A B σ F →
∀ (x y : ℝ) (a b : ℤ),
2 ≤ x →
x ^ (4 * ↑g ^ 2 * ε) ≤ y →
a ≤ b →
y - 1 ≤ ↑b - ↑a →
↑b - ↑a ≤ 2 * y →
(∀ t ∈ Finset.Ioc a b, ↑(Polynomial.eval t P.total).natAbs ≤ x ^ c) →
P.integerSum F a b ≤ C P.badDiscriminant * mainTerm P F x y
Enlarging the upper-bound constant handles the bounded range of x, so
the value-bound estimate is valid for every x ≥ 2. In applications this
keeps the coefficient-height threshold independent of an interval parameter.