OAI/NumberTheory/DukePrimeDegree/Entropy/NameErrorEntropy.lean

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7 declarations, 0 contain sorry, 0 declared as axioms

Entropy of finite names controlled by their coordinate errors

  1. theorem OAI.DukePrimeDegree.conditionalVectorEntropy_le_sum line 14
  2. theorem OAI.DukePrimeDegree.conditionalNameEntropy_le_errors line 52
  3. theorem OAI.DukePrimeDegree.nameEntropy_le_reference_errors line 72

    Source documentation

    A finite list of reference names pays its logarithmic cardinality; the remaining cost is proportional to the expected number of errors.

    theorem nameEntropy_le_reference_errors {Y α β : Type*} [MeasurableSpace Y]
        [MeasurableSpace α] [MeasurableSingletonClass α]
        [MeasurableSpace β] [MeasurableSingletonClass β]
        [Fintype α] [Nonempty α] [DecidableEq α] [Fintype β]
        (μ : Measure Y) [IsProbabilityMeasure μ] (N : ℕ)
        (P : Y → Fin N → α) (hP : Measurable P)
        (r : Y → β) (hr : Measurable r) (v : β → Fin N → α)
        {δ ε : ℝ} (hδ : 0 < δ) (hδ1 : δ < 1)
        (herr : (∑ i : Fin N, μ.real {y | P y i ≠ v (r y) i}) ≤ ε*N) :
        observationEntropy μ P ≤ Real.log (Fintype.card β) +
          (N : ℝ)*rareLabelCost (Fintype.card α) δ ε := by
    …

    Mentions: OAI.DukePrimeDegree.rareLabelCost

  4. theorem OAI.DukePrimeDegree.observationEntropyRate_le_approximate_names line 106
  5. theorem OAI.DukePrimeDegree.name_errors_le_bad_visits line 135

    Source documentation

    Orbit errors confined to a fixed measurable bad set cost at most its measure at each coordinate.

    theorem name_errors_le_bad_visits {Y α : Type*} [MeasurableSpace Y]
        (μ : Measure Y) [IsFiniteMeasure μ] {T : Y → Y}
        (hT : MeasurePreserving T μ μ) (P : Y → α) (N : ℕ)
        (R : Y → Fin N → α) (B : Set Y) (hB : MeasurableSet B)
        (hbad : ∀ y i, P (T^[i.val] y) ≠ R y i → T^[i.val] y ∈ B) :
        (∑ i : Fin N, μ.real {y | P (T^[i.val] y) ≠ R y i}) ≤ (N : ℝ)*μ.real B := by
    …
  6. theorem OAI.DukePrimeDegree.observationEntropyRate_le_fixed_reference_errors line 153

    Source documentation

    A fixed finite list of reference trajectories has zero asymptotic coding cost. Only the coordinate errors contribute to the entropy rate.

    theorem observationEntropyRate_le_fixed_reference_errors
        {Y α : Type*} [MeasurableSpace Y]
        [MeasurableSpace α] [MeasurableSingletonClass α]
        [Fintype α] [Nonempty α] [DecidableEq α]
        (μ : Measure Y) [IsProbabilityMeasure μ] {T : Y → Y}
        (hT : MeasurePreserving T μ μ) (P : Y → α) (hP : Measurable P)
        (M : ℕ) (r : ℕ → Y → Fin M) (hr : ∀ N, Measurable (r N))
        (v : ∀ N, Fin M → Fin N → α)
        {ε δ : ℝ} (hδ : 0 < δ) (hδ1 : δ < 1)
        (herr : ∀ N,
          (∑ i : Fin N, μ.real {y | P (T^[i.val] y) ≠ v N (r N y) i}) ≤ ε*N) :
        observationEntropyRate μ T P ≤ rareLabelCost (Fintype.card α) δ ε := by
    …

    Mentions: OAI.DukePrimeDegree.rareLabelCost

  7. theorem OAI.DukePrimeDegree.observationEntropyRate_le_zero_of_fixed_reference_approximations line 192

    Source documentation

    Arbitrarily accurate approximation by a fixed finite list of trajectories forces zero entropy for a finite observation.

    theorem observationEntropyRate_le_zero_of_fixed_reference_approximations
        {Y α : Type*} [MeasurableSpace Y]
        [MeasurableSpace α] [MeasurableSingletonClass α]
        [Fintype α] [Nonempty α] [DecidableEq α]
        (μ : Measure Y) [IsProbabilityMeasure μ] {T : Y → Y}
        (hT : MeasurePreserving T μ μ) (P : Y → α) (hP : Measurable P)
        (happrox : ∀ ε : ℝ, 0 < ε →
          ∃ (M : ℕ) (r : ℕ → Y → Fin M) (v : ∀ N, Fin M → Fin N → α),
            (∀ N, Measurable (r N)) ∧ ∀ N,
              (∑ i : Fin N, μ.real {y | P (T^[i.val] y) ≠ v N (r N y) i}) ≤ ε*N) :
        observationEntropyRate μ T P ≤ 0 := by
    …