OAI/Combinatorics/GotsmanLinial/ScalarIncrements.lean

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15 declarations, 0 contain sorry, 0 declared as axioms

Scalar inequalities for the one-sided coupling estimate

The increasing function couplingPotential m t = (t-m)|t-m|/2 controls squared distances from below and has a trapezoidal increment bound from above. All arguments here are algebraic, by splitting according to the positions of the endpoints relative to the center m.

  1. def OAI.LeanBlast.GotsmanLinial.couplingPotential line 18

    Source documentation

    The scalar potential used in the one-sided coupling argument.

    noncomputable def couplingPotential (m t : ℝ) : ℝ :=
    …
  2. theorem OAI.LeanBlast.GotsmanLinial.couplingPotential_self line 21
  3. theorem OAI.LeanBlast.GotsmanLinial.couplingPotential_increment_bounds line 25

    Source documentation

    Both increment inequalities hold even when the endpoints coincide.

    theorem couplingPotential_increment_bounds (m : ℝ) {u v : ℝ} (huv : u ≤ v) :
        (v - u) ^ 2 / 4 ≤ couplingPotential m v - couplingPotential m u ∧
          couplingPotential m v - couplingPotential m u ≤
            (v - u) / 2 * (|u - m| + |v - m|) := by
    …

    Mentions: OAI.LeanBlast.GotsmanLinial.couplingPotential

  4. theorem OAI.LeanBlast.GotsmanLinial.couplingPotential_increment_lower line 52
  5. theorem OAI.LeanBlast.GotsmanLinial.couplingPotential_increment_upper line 56
  6. theorem OAI.LeanBlast.GotsmanLinial.monotone_couplingPotential line 61
  7. theorem OAI.LeanBlast.GotsmanLinial.strictMono_couplingPotential line 66
  8. theorem OAI.LeanBlast.GotsmanLinial.couplingPotential_le_iff line 72
  9. theorem OAI.LeanBlast.GotsmanLinial.couplingPotential_lt_iff line 76
  10. theorem OAI.LeanBlast.GotsmanLinial.couplingPotential_eq_iff line 80
  11. theorem OAI.LeanBlast.GotsmanLinial.couplingPotential_sub_nonneg_iff line 84
  12. theorem OAI.LeanBlast.GotsmanLinial.couplingPotential_sub_pos_iff line 88
  13. theorem OAI.LeanBlast.GotsmanLinial.abs_couplingPotential_sub_of_le line 92
  14. theorem OAI.LeanBlast.GotsmanLinial.sq_sub_le_four_mul_abs_potential_sub line 99

    Source documentation

    The pointwise lower bound in the coupling argument, without ordering the two real variables.

    theorem sq_sub_le_four_mul_abs_potential_sub (m u v : ℝ) :
        (u - v) ^ 2 ≤ 4 * |couplingPotential m u - couplingPotential m v| := by
    …

    Mentions: OAI.LeanBlast.GotsmanLinial.couplingPotential

  15. theorem OAI.LeanBlast.GotsmanLinial.max_couplingPotential_increment_le line 111

    Source documentation

    An upper bound for the positive part of a potential increment under a one-sided bound on the original increment.

    theorem max_couplingPotential_increment_le (m a u v : ℝ)
        (ha : 0 ≤ a) (hstep : v - u ≤ a) :
        max (couplingPotential m v - couplingPotential m u) 0 ≤
          a / 2 * (|u - m| + |v - m|) := by
    …

    Mentions: OAI.LeanBlast.GotsmanLinial.couplingPotential