OAI/LinearAlgebra/MatrixMultiplication/AuxiliarySeparation/Growth/Profile.lean

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6 declarations, 0 contain sorry, 0 declared as axioms

Growth of the scalar profile

This file proves the scalar implication of Section 6 (Lemma 6.1). The profile properties are explicit hypotheses: the construction of a profile from a tensor character and the proof of those properties are separate arguments.

  1. structure OAI.MatrixMultiplication.AuxiliarySeparation.ScalarProfile line 23

    Source documentation

    The scalar profile hypotheses used in Section 6. Only positive indices carry mathematical content; the values on either coordinate axis are unused.

    structure ScalarProfile (t : ℝ) where
    …
  2. theorem OAI.MatrixMultiplication.AuxiliarySeparation.ScalarProfile.exists_row_slope line 39

    Source documentation

    Each row has a nonnegative limiting slope that bounds every increment from below and equals the limit of the row divided by its index.

    theorem exists_row_slope {t : ℝ} (P : ScalarProfile t) (a : ℕ) (ha : 1 ≤ a) :
        ∃ g : ℝ, 0 ≤ g ∧
          (∀ h : ℕ, 1 ≤ h → g ≤ P.value a (h + 1) - P.value a h) ∧
          Tendsto (fun h : ℕ => P.value a h / (h : ℝ)) atTop (𝓝 g) := by
    …

    Mentions: OAI.MatrixMultiplication.AuxiliarySeparation.ScalarProfile

  3. theorem OAI.MatrixMultiplication.AuxiliarySeparation.ScalarProfile.exists_row_slopes line 61

    Source documentation

    Choose the row slopes together, retaining their bounds and limits on all positive rows.

    theorem exists_row_slopes {t : ℝ} (P : ScalarProfile t) :
        ∃ g : ℕ → ℝ, ∀ a : ℕ, 1 ≤ a → 0 ≤ g a ∧
          (∀ h : ℕ, 1 ≤ h → g a ≤ P.value a (h + 1) - P.value a h) ∧
          Tendsto (fun h : ℕ => P.value a h / (h : ℝ)) atTop (𝓝 (g a)) := by
    …

    Mentions: OAI.MatrixMultiplication.AuxiliarySeparation.ScalarProfile

  4. theorem OAI.MatrixMultiplication.AuxiliarySeparation.ScalarProfile.diagonal_fourth_power_lower line 78

    Source documentation

    The exact polynomial lower bound on the diagonal, obtained from row concavity, shifted tripling, and the simultaneous scalar induction.

    theorem diagonal_fourth_power_lower {t : ℝ} (P : ScalarProfile t)
        (n : ℕ) (hn : 1 ≤ n) : (n : ℝ) ^ 4 ≤ P.value n n ^ 3 := by
    …

    Mentions: OAI.MatrixMultiplication.AuxiliarySeparation.ScalarProfile

  5. theorem OAI.MatrixMultiplication.AuxiliarySeparation.ScalarProfile.exponent_le_three_quarters line 108

    Source documentation

    Lemma 6.1: a positive symmetric profile satisfying the stated concavity, tripling, boundary, and rank bounds has exponent at most 3/4.

    theorem exponent_le_three_quarters {t : ℝ} (P : ScalarProfile t) (ht : 0 < t) :
        t ≤ 3 / 4 := by
    …

    Mentions: OAI.MatrixMultiplication.AuxiliarySeparation.ScalarProfile

  6. theorem OAI.MatrixMultiplication.AuxiliarySeparation.profile_exponent_le_three_quarters line 122

    Source documentation

    The scalar profile implication, with every profile assumption displayed explicitly rather than bundled in ScalarProfile.

    theorem profile_exponent_le_three_quarters {P : ℕ → ℕ → ℝ} {t : ℝ}
        (ht : 0 < t)
        (hpositive : ∀ a b : ℕ, 1 ≤ a → 1 ≤ b → 0 < P a b)
        (hsymmetric : ∀ a b : ℕ, 1 ≤ a → 1 ≤ b → P a b = P b a)
        (hboundary : ∀ b : ℕ, 1 ≤ b → P 1 b = (b : ℝ))
        (hconcave : ∀ a h : ℕ, 1 ≤ a → 2 ≤ h →
          P a (h - 1) + P a (h + 1) ≤ 2 * P a h)
        (htripling : ∀ a h : ℕ, 1 ≤ a → 1 ≤ h →
          3 * P a h ≤ P a (3 * h + a - 1))
        (hrank : ∀ a b : ℕ, 1 ≤ a → 1 ≤ b →
          P a b ≤ ((a : ℝ) + (b : ℝ) - 1) ^ (1 / t)) :
        t ≤ 3 / 4 := by
    …