OAI/Combinatorics/ExpectationThreshold/ScaleBounds.lean

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15 declarations, 0 contain sorry, 0 declared as axioms

The largest admissible scale

The cutoff is constructed as the first index whose next scale fails. Its existence follows from the Archimedean property and the elementary lower bound scaleSum s ≥ s. No finite search bound or computed large power is used.

  1. theorem OAI.TalagrandThreshold.scaleSum_succ line 25
  2. theorem OAI.TalagrandThreshold.scaleSum_monotone line 29
  3. theorem OAI.TalagrandThreshold.scaleSum_ge_nat line 35
  4. theorem OAI.TalagrandThreshold.scaleSum_le_two_pow line 43

    Source documentation

    The finite geometric sum is at most twice its largest power.

    theorem scaleSum_le_two_pow (s : ℕ) : scaleSum s ≤ 2 * (256 : ℝ) ^ s := by
    …

    Mentions: OAI.TalagrandThreshold.scaleSum

  5. theorem OAI.TalagrandThreshold.half_geometric_sum_identity line 51
  6. theorem OAI.TalagrandThreshold.half_geometric_sum_le_one line 60
  7. theorem OAI.TalagrandThreshold.scale_next_fail_exists line 67

    Source documentation

    Some next scale fails whenever the density is positive.

    theorem scale_next_fail_exists {p : ℝ} (hp : 0 < p) :
        ∃ s : ℕ, 1 / 2 < p * scaleSum (s + 1) := by
    …

    Mentions: OAI.TalagrandThreshold.scaleSum

  8. def OAI.TalagrandThreshold.maxScale line 81

    Source documentation

    The largest admissible scale; its irrelevant nonpositive-density value is zero.

    noncomputable def maxScale (p : ℝ) : ℕ := by
    …
  9. theorem OAI.TalagrandThreshold.maxScale_eq_find line 85
  10. theorem OAI.TalagrandThreshold.maxScale_next_fail line 90
  11. theorem OAI.TalagrandThreshold.maxScale_admissible line 96
  12. theorem OAI.TalagrandThreshold.maxScale_largest line 108

    Source documentation

    Every admissible integer is at most the constructed cutoff.

    theorem maxScale_largest {p : ℝ} (hp : 0 < p) {t : ℕ}
        (ht : p * scaleSum t ≤ 1 / 2) : t ≤ maxScale p := by
    …

    Mentions: OAI.TalagrandThreshold.scaleSum, OAI.TalagrandThreshold.maxScale

  13. theorem OAI.TalagrandThreshold.exists_scale line 117

    Source documentation

    The exact pair of cutoff inequalities used by the rounding argument.

    theorem exists_scale {p : ℝ} (hp : 0 < p) :
        ∃ s : ℕ, p * scaleSum s ≤ 1 / 2 ∧ 1 / 2 < p * scaleSum (s + 1) :=
    …

    Mentions: OAI.TalagrandThreshold.scaleSum

  14. theorem OAI.TalagrandThreshold.tail_lt_four_mul_p line 122

    Source documentation

    Failure at the next scale controls the residual color contribution.

    theorem tail_lt_four_mul_p {p : ℝ} {s : ℕ} (hp : 0 < p)
        (hnext : 1 / 2 < p * scaleSum (s + 1)) :
        1 / (512 : ℝ) ^ (s + 1) < 4 * p := by
    …

    Mentions: OAI.TalagrandThreshold.scaleSum

  15. theorem OAI.TalagrandThreshold.maxScale_tail_lt line 137