Mathesis

F2 — given A nonempty, BlackwellEquivalent (learnerExperiment K) publicOnlyExperiment ↔ AuditSealed K (blackwell1953).

DeclAuditCP.blackwellEquivalent_publicOnly_iff_auditSealed
∀ {S : Type uS} {A : Type uA} {Y : Type uY} [Nonempty A] (K : AuditCP.AuditChannel S A Y),
  AuditCP.BlackwellEquivalent (AuditCP.learnerExperiment K) AuditCP.publicOnlyExperiment ↔ AuditCP.AuditSealed K
Layout
ThesisStepDefinition
blackwellEquivalent_publi…theorempublicOnly_blackwellBelow…theoremlearner_blackwellBelow_pu…theorempmf_map_publicTag_injecti…theoremauditSealed_iff_factorsTh…theoremAuditChanneldefAuditExperimentdefAuditSealeddefBlackwellBelowdefBlackwellEquivalentdefFactorsThroughPublicdeflearnerExperimentdefpublicOnlyExperimentdef
  1. DeclAuditCP.blackwellEquivalent_publicOnly_iff_auditSealedDeclaration kindtheorem
    ∀ {S : Type uS} {A : Type uA} {Y : Type uY} [Nonempty A] (K : AuditCP.AuditChannel S A Y),
      AuditCP.BlackwellEquivalent (AuditCP.learnerExperiment K) AuditCP.publicOnlyExperiment ↔ AuditCP.AuditSealed K
    Uses
  2. DeclAuditCP.publicOnly_blackwellBelow_learnerDeclaration kindtheorem

    F2a — public information is Blackwell-below the complete learner view: BlackwellBelow publicOnlyExperiment (learnerExperiment K).

    ∀ {S : Type uS} {A : Type uA} {Y : Type uY} (K : AuditCP.AuditChannel S A Y),
      AuditCP.BlackwellBelow AuditCP.publicOnlyExperiment (AuditCP.learnerExperiment K)
    Used by
  3. DeclAuditCP.learner_blackwellBelow_publicOnly_iff_auditSealedDeclaration kindtheorem

    F2b — given A nonempty, BlackwellBelow (learnerExperiment K) publicOnlyExperiment ↔ AuditSealed K (blackwell1953).

    ∀ {S : Type uS} {A : Type uA} {Y : Type uY} [Nonempty A] (K : AuditCP.AuditChannel S A Y),
      AuditCP.BlackwellBelow (AuditCP.learnerExperiment K) AuditCP.publicOnlyExperiment ↔ AuditCP.AuditSealed K
    Uses
    Used by
  4. DeclAuditCP.pmf_map_publicTag_injectiveDeclaration kindtheorem

    Pushing a PMF on Y through the tag y ↦ (s, y) is injective.

    ∀ {S : Type uS} {Y : Type uY} (s : S), Function.Injective fun p => PMF.map (fun y => (s, y)) p
    Used by
  5. DeclAuditCP.auditSealed_iff_factorsThroughPublicDeclaration kindtheorem

    F1 — given A nonempty, AuditSealed K ↔ FactorsThroughPublic K.

    ∀ {S : Type uS} {A : Type uA} {Y : Type uY} [Nonempty A] (K : AuditCP.AuditChannel S A Y),
      AuditCP.AuditSealed K ↔ AuditCP.FactorsThroughPublic K
    Used by
  6. DefinitionAuditCP.AuditChanneldef

    B6 — AuditChannel S A Y is AuditExperiment (S × A) Y, an experiment whose parameter is split into a public coordinate S and an audit coordinate A.

    AuditCP.AuditIndex → AuditCP.AuditIndex → AuditCP.AuditIndex → Type (max u v w)
  7. DefinitionAuditCP.AuditExperimentdef

    B5 — AuditExperiment Θ X is the type of parameter-indexed discrete observation laws Θ → PMF X.

    AuditCP.AuditIndex → AuditCP.AuditIndex → Type (max u v)
  8. DefinitionAuditCP.AuditSealeddef

    The channel K is audit-sealed: its output law at fixed public state s does not depend on the audit state a.

    {S : Type uS} → {A : Type uA} → {Y : Type uY} → AuditCP.AuditChannel S A Y → Prop
  9. DefinitionAuditCP.BlackwellBelowdef

    E₀ is Blackwell-below E₁ when some garbling G of E₁'s output reproduces E₀: ∃ G, ∀ θ, E₀ θ = (E₁ θ).bind G (blackwell1953).

    {Θ : Type uΘ} → {X₀ : Type uX₀} → {X₁ : Type uX₁} → AuditCP.AuditExperiment Θ X₀ → AuditCP.AuditExperiment Θ X₁ → Prop
  10. DefinitionAuditCP.BlackwellEquivalentdef

    E₀ and E₁ are Blackwell-equivalent when each is Blackwell-below the other (blackwell1953).

    {Θ : Type uΘ} → {X₀ : Type uX₀} → {X₁ : Type uX₁} → AuditCP.AuditExperiment Θ X₀ → AuditCP.AuditExperiment Θ X₁ → Prop
  11. DefinitionAuditCP.FactorsThroughPublicdef

    The channel K factors through the public coordinate: ∃ H, ∀ s a, K (s, a) = H s.

    {S : Type uS} → {A : Type uA} → {Y : Type uY} → AuditCP.AuditChannel S A Y → Prop
  12. DefinitionAuditCP.learnerExperimentdef

    The channel revealing the public state together with K's output, fun sa => (K sa).map (fun y => (sa.1, y)).

    {S : Type uS} → {A : Type uA} → {Y : Type uY} → AuditCP.AuditChannel S A Y → AuditCP.AuditChannel S A (S × Y)
  13. DefinitionAuditCP.publicOnlyExperimentdef

    The channel revealing exactly the public state s and nothing else, fun (s, a) => PMF.pure s.

    {S : Type uS} → {A : Type uA} → AuditCP.AuditChannel S A S
DOIMTH.R-2026-6016
Cite

Verification

Replay
accepted
Axioms
Classical.choiceQuot.soundpropext
Statement identity
not-applicable
Substrate
Lean 4 kernel v4.31.0
Dictionary pin
design-lab@5802df4 · initial
Frozen export
304b019f2077
Verified
2026-09-24T00:00:00Z