Mathesis

Pinsker's inequality with the sharp constant. tvDistReal P Q ≤ sqrt(klDivReal P Q / 2) for probability measures P ≪ Q with finite KL divergence.

DeclInformationTheory.pinsker_proof
∀ {α : Type u_1} [inst : MeasurableSpace α] (P Q : MeasureTheory.Measure α)
  [inst_1 : MeasureTheory.IsProbabilityMeasure P] [inst_2 : MeasureTheory.IsProbabilityMeasure Q],
  P.AbsolutelyContinuous Q →
    MeasureTheory.Integrable (MeasureTheory.llr P Q) P →
      MeasureTheory.tvDistReal P Q ≤ √(InformationTheory.klDivReal P Q / 2)

Arguments

DOIAuthorDate
MTH.R-2026-6024Dhruv GuptaDhruv Gupta2026-09-24T00:00:00Z
DOIMTH.C-2026-6024
Cite

Verification

Library
ZPM.InformationTheory.Pinsker.General
Statement digest
19e1fb4bee5e
First verified
2026-09-24T00:00:00Z