OAI/Analysis/Nonexpansive/TreeBudget.lean

GitHub source file

17 declarations, 0 contain sorry, 0 declared as axioms

Budgets attached to retained candidate ordinals

The label of a retained node is its zero-based ordinal in the global candidate sequence. Thus the one-based label ℓ = label + 1 gives the budget 2 ^ (-ℓ - 8) = (1 / 2) ^ (label + 9). Injectivity, rather than a new enumeration of retained nodes, compares their total with the candidate series. The actual tree construction supplies this label and its injectivity proof.

  1. def OAI.ReflexiveFixedPoints.candidateBudget line 24

    Source documentation

    The dyadic budget of the candidate with zero-based ordinal n.

    def candidateBudget (n : ℕ) : ℝ := (1 / 2 : ℝ) ^ (n + 9)
  2. theorem OAI.ReflexiveFixedPoints.candidateBudget_pos line 26
  3. theorem OAI.ReflexiveFixedPoints.candidateBudget_nonneg line 29
  4. theorem OAI.ReflexiveFixedPoints.candidateBudget_le_one line 32
  5. theorem OAI.ReflexiveFixedPoints.hasSum_candidateBudget line 36

    Source documentation

    The complete candidate series has sum exactly 1 / 256.

    theorem hasSum_candidateBudget : HasSum candidateBudget (1 / 256 : ℝ) := by
    …

    Mentions: OAI.ReflexiveFixedPoints.candidateBudget

  6. theorem OAI.ReflexiveFixedPoints.summable_candidateBudget line 43
  7. theorem OAI.ReflexiveFixedPoints.tsum_candidateBudget line 46
  8. abbrev OAI.ReflexiveFixedPoints.OrderedTree.NonrootNode line 52

    Source documentation

    Every nonroot node, retaining its actual positive level.

    abbrev NonrootNode (T : OrderedTree) := Σ k : ℕ, T.Node (k + 1)
    …

    Mentions: OAI.ReflexiveFixedPoints.OrderedTree

  9. def OAI.ReflexiveFixedPoints.OrderedTree.retainedBudget line 57

    Source documentation

    The retained budget uses the original global candidate label.

    def retainedBudget (label : T.NonrootNode → ℕ) (v : T.NonrootNode) : ℝ :=
    …
  10. theorem OAI.ReflexiveFixedPoints.OrderedTree.retainedBudget_pos line 60
  11. theorem OAI.ReflexiveFixedPoints.OrderedTree.retainedBudget_nonneg line 64
  12. theorem OAI.ReflexiveFixedPoints.OrderedTree.retainedBudget_le_one line 68
  13. theorem OAI.ReflexiveFixedPoints.OrderedTree.summable_retainedBudget line 74

    Source documentation

    Retaining a subset of globally distinct candidate labels preserves summability. No bound on the number of nodes at later levels is needed.

    theorem summable_retainedBudget (label : T.NonrootNode → ℕ)
        (hlabel : Function.Injective label) : Summable (retainedBudget label) := by
    …

    Mentions: OAI.ReflexiveFixedPoints.OrderedTree.retainedBudget

  14. theorem OAI.ReflexiveFixedPoints.OrderedTree.tsum_retainedBudget_le line 79

    Source documentation

    The total retained budget is at most the complete candidate budget.

    theorem tsum_retainedBudget_le (label : T.NonrootNode → ℕ)
        (hlabel : Function.Injective label) :
        (∑' v, retainedBudget label v) ≤ (1 / 256 : ℝ) := by
    …

    Mentions: OAI.ReflexiveFixedPoints.OrderedTree.retainedBudget

  15. theorem OAI.ReflexiveFixedPoints.OrderedTree.tsum_retainedBudget_le_one_div_128 line 87
  16. theorem OAI.ReflexiveFixedPoints.OrderedTree.sum_retainedBudget_le line 93

    Source documentation

    Every finite retained selection satisfies the same global budget bound.

    theorem sum_retainedBudget_le (label : T.NonrootNode → ℕ)
        (hlabel : Function.Injective label) (s : Finset T.NonrootNode) :
        (∑ v ∈ s, retainedBudget label v) ≤ (1 / 256 : ℝ) := by
    …

    Mentions: OAI.ReflexiveFixedPoints.OrderedTree.retainedBudget

  17. theorem OAI.ReflexiveFixedPoints.OrderedTree.sum_retainedBudget_comp_le line 104

    Source documentation

    A finite truncation, or any finite injectively indexed collection of actual nonroot nodes, satisfies the complete retained budget bound.

    theorem sum_retainedBudget_comp_le {ι : Type*} [Fintype ι]
        (label : T.NonrootNode → ℕ) (hlabel : Function.Injective label)
        (node : ι → T.NonrootNode) (hnode : Function.Injective node) :
        (∑ i, retainedBudget label (node i)) ≤ (1 / 256 : ℝ) := by
    …

    Mentions: OAI.ReflexiveFixedPoints.OrderedTree.retainedBudget