OAI/GroupTheory/PolycyclicRecognition/Analysis/PairMeasureScaling.lean

GitHub source file

4 declarations, 0 contain sorry, 0 declared as axioms

Normalizing a finite stationary measure

The inverse coupling produces a finite nonzero measure. Its probability normalization retains the same sublinear error and therefore the same prescribed inverse coefficient.

  1. theorem OAI.PolycyclicRecognition.eLpNorm_pairHeight_error_finite line 26

    Source documentation

    The pointwise error and the Hilbert error agree for every finite measure.

    theorem eLpNorm_pairHeight_error_finite
        (μ : Measure (NormalizedPair G Λ)) [IsFiniteMeasure μ]
        (π : G →* Multiplicative W) (hπ : Continuous fun g => (π g).toAdd)
        (l : G →* Multiplicative W) (g : G) :
        eLpNorm (fun p : NormalizedPair G Λ => pairHeight π g p - (l g).toAdd) 2 μ =
          ENNReal.ofReal ‖pairHeightL2 μ π hπ g - Lp.const 2 μ (l g).toAdd‖ := by
    …

    Mentions: OAI.PolycyclicRecognition.NormalizedPair, OAI.PolycyclicRecognition.pairHeight, OAI.PolycyclicRecognition.pairHeightL2

  2. theorem OAI.PolycyclicRecognition.norm_pairHeight_error_smul_measure line 39

    Source documentation

    Scaling the measure scales every height-error norm by one fixed factor.

    theorem norm_pairHeight_error_smul_measure
        (μ : Measure (NormalizedPair G Λ)) [IsFiniteMeasure μ]
        (c : ℝ≥0∞) [IsFiniteMeasure (c • μ)]
        (π : G →* Multiplicative W) (hπ : Continuous fun g => (π g).toAdd)
        (l : G →* Multiplicative W) (g : G) :
        ‖pairHeightL2 (c • μ) π hπ g - Lp.const 2 (c • μ) (l g).toAdd‖ =
          (c ^ (1 / 2 : ℝ)).toReal * ‖pairHeightL2 μ π hπ g - Lp.const 2 μ (l g).toAdd‖ := by
    …

    Mentions: OAI.PolycyclicRecognition.NormalizedPair, OAI.PolycyclicRecognition.pairHeightL2

  3. theorem OAI.PolycyclicRecognition.pairHeight_sublinear_smul_measure line 56

    Source documentation

    Sublinearity survives every finite scaling of the stationary measure.

    theorem pairHeight_sublinear_smul_measure
        (μ : Measure (NormalizedPair G Λ)) [IsFiniteMeasure μ]
        (c : ℝ≥0∞) [IsFiniteMeasure (c • μ)]
        (π l : G →* Multiplicative W) (hπ : Continuous fun g => (π g).toAdd)
        (hsub : ∀ ε : ℝ, 0 < ε → ∃ B : ℝ, 0 ≤ B ∧ ∀ g,
          ‖pairHeightL2 μ π hπ g - Lp.const 2 μ (l g).toAdd‖ ≤ ε * dist 1 g + B) :
        ∀ ε : ℝ, 0 < ε → ∃ B : ℝ, 0 ≤ B ∧ ∀ g,
          ‖pairHeightL2 (c • μ) π hπ g - Lp.const 2 (c • μ) (l g).toAdd‖ ≤
            ε * dist 1 g + B := by
    …

    Mentions: OAI.PolycyclicRecognition.NormalizedPair, OAI.PolycyclicRecognition.pairHeightL2

  4. theorem OAI.PolycyclicRecognition.exists_probability_with_same_pairHeight_slope line 83

    Source documentation

    A finite nonzero invariant measure can be normalized without changing its prescribed sublinear slope.

    theorem exists_probability_with_same_pairHeight_slope
        (μ : Measure (NormalizedPair G Λ)) [IsFiniteMeasure μ]
        [SMulInvariantMeasure G (NormalizedPair G Λ) μ] (hμ : μ ≠ 0)
        (π l : G →* Multiplicative W) (hπ : Continuous fun g => (π g).toAdd)
        (hsub : ∀ ε : ℝ, 0 < ε → ∃ B : ℝ, 0 ≤ B ∧ ∀ g,
          ‖pairHeightL2 μ π hπ g - Lp.const 2 μ (l g).toAdd‖ ≤ ε * dist 1 g + B) :
        ∃ ν : Measure (NormalizedPair G Λ), ∃ hν : IsProbabilityMeasure ν,
          SMulInvariantMeasure G (NormalizedPair G Λ) ν ∧
          let := hν
    …

    Mentions: OAI.PolycyclicRecognition.NormalizedPair, OAI.PolycyclicRecognition.pairHeightL2