Measure, Integration & Real Analysis · Problem 9B.1
Linear Maps on Hilbert Spaces — Sheldon Axler
Mathematics — Measure Theory · hahn-decomposition-uniqueness
Problem
Suppose ν is a real measure on a measurable space (X,S). Prove that the Hahn decomposition of ν is almost unique, in the sense that if A,B and A′,B′ are pairs satisfying the Hahn Decomposition Theorem (9.23), then
∣ν∣(A∖A′)=∣ν∣(A′∖A)=∣ν∣(B∖B′)=∣ν∣(B′∖B)=0.