OAI/NumberTheory/DukePrimeDegree/Entropy/MetricEntropy.lean

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5 declarations, 0 contain sorry, 0 declared as axioms

The entropy functional in the published dynamical inputs

A finite measurable partition is represented by its finite-valued label map. Its length-N names encode the join of its first N inverse images under the transformation. The liminf definition agrees with the usual limit for invariant probabilities by subadditivity; proving that agreement and the published entropy theorems is still part of the outstanding work.

  1. structure OAI.DukePrimeDegree.MeasurablePartition line 23

    Source documentation

    A finite measurable partition, allowing empty atoms.

    structure MeasurablePartition (X : Type*) [MeasurableSpace X] (k : ℕ) where
    …
  2. def OAI.DukePrimeDegree.nameAtom line 28

    Source documentation

    The atoms of the joined partition through time N-1.

    def nameAtom {X : Type*} [MeasurableSpace X] {k : ℕ}
        (P : MeasurablePartition X k) (T : X → X) (N : ℕ)
        (word : Fin N → Fin (k + 1)) : Set X :=
    …

    Mentions: OAI.DukePrimeDegree.MeasurablePartition

  3. def OAI.DukePrimeDegree.blockEntropy line 34

    Source documentation

    Shannon entropy of the finite joined partition, with natural logs.

    noncomputable def blockEntropy {X : Type*} [MeasurableSpace X] {k : ℕ}
        (P : MeasurablePartition X k) (T : X → X) (μ : Measure X) (N : ℕ) : ℝ :=
    …

    Mentions: OAI.DukePrimeDegree.MeasurablePartition

  4. def OAI.DukePrimeDegree.partitionEntropyRate line 40

    Source documentation

    Entropy rate of one partition. The indexing N+1 avoids division by zero.

    noncomputable def partitionEntropyRate {X : Type*} [MeasurableSpace X] {k : ℕ}
        (P : MeasurablePartition X k) (T : X → X) (μ : Measure X) : ℝ≥0∞ :=
    …

    Mentions: OAI.DukePrimeDegree.MeasurablePartition

  5. def OAI.DukePrimeDegree.metricEntropy line 45

    Source documentation

    Kolmogorov--Sinai entropy, as the supremum over finite measurable partitions.

    noncomputable def metricEntropy {X : Type*} [MeasurableSpace X]
        (T : X → X) (μ : Measure X) : ℝ≥0∞ :=
    …