teorth/PFR
Source indexedlemma · leanprover/lean4:v4.33.0-rc1
continuous_rdist_restrict_probabilityMeasure
PFR.ForMathlib.Entropy.RuzsaDist · PFR/ForMathlib/Entropy/RuzsaDist.lean:84 to 105
Source documentation
Ruzsa distance depends continuously on the measure.
Exact Lean statement
lemma continuous_rdist_restrict_probabilityMeasure [Finite G]
[TopologicalSpace G] [DiscreteTopology G] [BorelSpace G] :
Continuous
(fun (μ : ProbabilityMeasure G × ProbabilityMeasure G) ↦
d[id ; μ.1.toMeasure # id ; μ.2.toMeasure])Complete declaration
Lean source
Full Lean sourceLean 4
lemma continuous_rdist_restrict_probabilityMeasure [Finite G] [TopologicalSpace G] [DiscreteTopology G] [BorelSpace G] : Continuous (fun (μ : ProbabilityMeasure G × ProbabilityMeasure G) ↦ d[id ; μ.1.toMeasure # id ; μ.2.toMeasure]) := by simp [rdist_def] have obs₀ : Continuous (fun (μ : ProbabilityMeasure G × ProbabilityMeasure G) ↦ H[fun x ↦ x.1 - x.2 ; μ.1.toMeasure.prod μ.2.toMeasure]) := by simp_rw [entropy_def] have diff_cts : Continuous (fun (x : G × G) ↦ x.1 - x.2) := by continuity have key₁ := ProbabilityMeasure.continuous_prod (α := G) (β := G) have key₂ := ProbabilityMeasure.continuous_map diff_cts convert! continuous_measureEntropy_probabilityMeasure.comp (key₂.comp key₁) have obs₁ : Continuous (fun (μ : ProbabilityMeasure G × ProbabilityMeasure G) ↦ H[id ; μ.1.toMeasure]) := by convert (continuous_measureEntropy_probabilityMeasure (Ω := G)).comp continuous_fst simp [entropy_def] have obs₂ : Continuous (fun (μ : ProbabilityMeasure G × ProbabilityMeasure G) ↦ H[id ; μ.2.toMeasure]) := by convert (continuous_measureEntropy_probabilityMeasure (Ω := G)).comp continuous_snd simp [entropy_def] continuity