OAI/NumberTheory/EgyptianFractions/UniformSecondMoment.lean

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4 declarations, 0 contain sorry, 0 declared as axioms

  1. theorem OAI.Problem337.norm_expect_sq_eq_expect_pairs line 9
  2. theorem OAI.Problem337.uniform_second_moment_identity line 15
  3. theorem OAI.Problem337.uniform_boolean_second_moment_bound line 26

    Source documentation

    Uniform finite-average version of the Hamming second-moment reduction.

    theorem uniform_boolean_second_moment_bound {Ω : Type*} [Fintype Ω] [Nonempty Ω]
        (m : ℕ) (z : Ω → (Fin m → Bool) → ℂ)
        (hz : ∀ ω i, ‖z ω i‖ ≤ 1) (δ : ℝ) (hδ : 0 ≤ δ)
        (hgood : ∀ i j, (m : ℝ) / 4 ≤ (hammingDist i j : ℝ) →
          ‖𝔼 ω, z ω i * star (z ω j)‖ ≤ δ) :
        (𝔼 ω, ‖𝔼 i, z ω i‖ ^ 2) ≤ Real.exp (-(m : ℝ) / 16) + δ := by
    …
  4. theorem OAI.Problem337.uniform_boolean_random_second_moment_bound line 74

    Source documentation

    Uniform-mean final random estimate, directly matching the second moment of the sampled Boolean-product exponential average.

    theorem uniform_boolean_random_second_moment_bound {Ω : Type*}
        [Fintype Ω] [Nonempty Ω] (m : ℕ) (V : ℝ)
        (z : Ω → (Fin m → Bool) → ℂ) (hz : ∀ ω i, ‖z ω i‖ ≤ 1)
        (hlarge : 50 ≤ min (m : ℝ) V)
        (hgood : ∀ i j, (m : ℝ) / 4 ≤ (hammingDist i j : ℝ) →
          ‖𝔼 ω, z ω i * star (z ω j)‖ ≤ Real.exp (-V / 20) + Real.exp (-V / 5)) :
        (𝔼 ω, ‖𝔼 i, z ω i‖ ^ 2) ≤ Real.exp (-min (m : ℝ) V / 100) := by
    …