Fubini and Tonelli interchange
On sigma-finite measure spaces, a nonnegative product-measurable function has equal product and iterated integrals, possibly infinite.
Key knowledge
On sigma-finite measure spaces, a nonnegative product-measurable function has equal product and iterated integrals, possibly infinite. If its absolute integral is finite, the signed integral is finite and both integration orders give the product integral.
Conditions and scope
- Measurability and sigma-finiteness are explicit here; signed section integrals are defined almost everywhere.
- Conditionally convergent signed iterated integrals alone do not establish the conclusion.
Sources · 1
References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
Evidence and review
Section 5B, Theorems 5.28 (Tonelli) and 5.32 (Fubini), printed pages 129 and 132.
2026-10-10 · Independent AI editorial review: All241 compact claims, hypotheses, displayed equations/conventions and all596 origin semantic links read; entire241-entry author exact-source inspection matrix and declared limitations reviewed. Prior105 actual inherited Mathematics/Information records read for whole-inventory breadth. Targeted independent primary sections are listed below; this does NOT claim every cited source body or every proof was independently re-read. This is AI reference-content review, not human disciplinary certification, exhaustive textbook reproduction or experimental replication. Receipt: mathematics-information-independent-content-review.1.
Entry details
Permanent link to this entry ↗- Record identity
- math-fubini-tonelli
- Revision
- university-core.1
- Structured reference record
- University core expansion