OAI/RepresentationTheory/KazhdanLusztig/Comparison.lean

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8 declarations, 0 contain sorry, 0 declared as axioms

Reciprocal low-degree rigidity and positive elementary sheaf-transfer inequalities.

  1. theorem OAI.KLInvariance.Comparison.low_degree_zero_of_eval_reciprocal line 24

    Source documentation

    A polynomial supported strictly below the middle cannot equal its reciprocal on an open real interval. This discharges the final rigidity step after the source's two comparison inequalities have been combined.

    theorem low_degree_zero_of_eval_reciprocal (p : ℝ[X]) (d : ℕ)
        (hp : 2 * p.natDegree < d)
        (h : ∀ q : ℝ, 0 < q → q < 1 → p.eval q = q ^ d * p.eval q⁻¹) : p = 0 := by
    …
  2. theorem OAI.KLInvariance.Comparison.eq_of_eval_difference_reciprocal line 50

    Source documentation

    The exact polynomial conclusion from reciprocal difference equality, without assuming positivity of KL coefficients.

    theorem eq_of_eval_difference_reciprocal (p p' : ℤ[X]) (d : ℕ)
        (hp : 2 * p.natDegree < d) (hp' : 2 * p'.natDegree < d)
        (h : ∀ q : ℝ, 0 < q → q < 1 →
          p.eval₂ (Int.castRingHom ℝ) q - p'.eval₂ (Int.castRingHom ℝ) q =
          q ^ d * (p.eval₂ (Int.castRingHom ℝ) q⁻¹ -
            p'.eval₂ (Int.castRingHom ℝ) q⁻¹)) : p = p' := by
    …
  3. def OAI.KLInvariance.Comparison.transfer line 74

    Source documentation

    The genuine elementary transfer id + T E_xy from the source's edge schedule, expressed on vectors rather than with a choice of enumeration.

    noncomputable def transfer (T : ℝ) (x y : V) (v : V → ℝ) : V → ℝ :=
    …
  4. theorem OAI.KLInvariance.Comparison.transfer_monotone line 77
  5. theorem OAI.KLInvariance.Comparison.transfer_injective line 85
  6. def OAI.KLInvariance.Comparison.idealState line 98
  7. theorem OAI.KLInvariance.Comparison.state_le_ideal line 105

    Source documentation

    Propagation of the actual Hilbert-series bound through all earlier edges. No freeness or positivity of the vectors is needed for this part.

    theorem state_le_ideal (T : ℝ) (hT : 0 ≤ T) (edges : ℕ → V × V)
        (D : ℕ → V → ℝ) (n : ℕ)
        (hstep : ∀ k < n, D (k + 1) ≤ transfer T (edges k).1 (edges k).2 (D k)) :
        D n ≤ idealState T edges (D 0) n := by
    …

    Mentions: OAI.KLInvariance.Comparison.transfer, OAI.KLInvariance.Comparison.idealState

  8. theorem OAI.KLInvariance.Comparison.every_step_eq_of_endpoint_eq line 119

    Source documentation

    Endpoint equality forces every edge-image deficit to vanish, including those invisible in codimension one. This uses actual inequalities and the injectivity of elementary edge transfers; it does not assume image equality. It is the no-deficit conclusion of source (6.8).

    theorem every_step_eq_of_endpoint_eq (T : ℝ) (hT : 0 ≤ T)
        (edges : ℕ → V × V) (D : ℕ → V → ℝ) (n : ℕ)
        (hedges : ∀ k < n, (edges k).1 ≠ (edges k).2)
        (hstep : ∀ k < n, D (k + 1) ≤ transfer T (edges k).1 (edges k).2 (D k))
        (hend : D n = idealState T edges (D 0) n) :
        ∀ k < n, D (k + 1) = transfer T (edges k).1 (edges k).2 (D k) := by
    …

    Mentions: OAI.KLInvariance.Comparison.transfer, OAI.KLInvariance.Comparison.idealState