How statement and proof provenance work
The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.
- Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
- AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
- AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.
These labels describe origin, not correctness: citations and verification chips remain separate evidence.
A space-filling source current reduces to the negative internal integration current
Statement
Let be an oriented smooth four-manifold, let be a compact oriented smooth six-manifold, and use the product orientation on with the factor first. Let have , and let be a compact oriented embedded three-manifold without boundary. Orient by the same product order.
Write and for the projections. For an integer and , define by integration over the oriented factor, with convention for decomposable terms of external degree four and zero external integral for other external degrees. Equivalently, in oriented product coordinates, retain the terms containing the oriented external volume element and integrate their coefficient functions over , using a partition of unity in when needed. Define the external-independent product extension of an internal degree- current by For a smooth internal -form , this convention gives .
The ten-dimensional source-current convention for compactly supported test seven-forms has the following reduction to the mathematical current convention of De Rham currents of compact oriented source cycles: For an internal smooth -form and an internal current of degree , pairing the product extensions just defined with gives respectively and . For , the current differential also reduces on these product tests: the pairing of with equals the pairing of with .
Facts & Assumptions
Given: The oriented manifolds and product orientation above, the normalized compactly supported top form , and the degree-current convention of De Rham currents of compact oriented source cycles.
De Rham currents of compact oriented source cycles defines , , and .
Fubini over a bounded Jordan set when all but a content-zero family of sections are integrable applies to Riemann-integrable functions on bounded Jordan sets with integrable sections outside a content-zero exceptional set. Below it is applied only to smooth functions, extended by zero, on bounded product rectangles; every section is integrable.
For the possibly noncompact oriented manifold of dimension , use compactly supported tests: let be the smooth -forms supported in a fixed compact , with the coordinate coefficient-and-derivative seminorms of [F1]. Give the finest locally convex topology making every inclusion continuous. A degree- current is a continuous real-linear functional on . Define for tests of degree and put in top degree. The coordinate formula for preserves supports and bounds each output seminorm of order by finitely many input seminorms of order ; hence this defines a continuous current. For a smooth -form , set and . These definitions agree with [F1] on compact manifolds. They are the compact-test conventions of Dinh–Sibony, §3.1 Definition 3.1.3, §3.2 and §4.4; no noncompact assertion is imported from [F1].
Finite chart localization gives choice-free integration and compact Stokes constructs compactly supported top-form integrals using finitely many smooth chart cutoffs summing to one near the support, proves independence of those choices, and applies without compactness of the manifold. This supplies all chart localizations below.
Proof
Given: The product geometry, , and the stated test forms.
For any compactly supported top forms on and on or , apply [F5] separately to their compact supports. Write the resulting finite chart pieces as and in oriented charts. Their coefficient functions extend smoothly by zero outside their chart images and have compact support. Choose bounded rectangles containing these supports. The function is continuous on the Jordan rectangle , with continuous sections everywhere. Thus [F2] gives . Summing the finite chart pieces and using [F5] proves with the external-first orientation. In particular, moving past has sign , so . Taking gives .
The fibre integral in the Statement is well-defined and continuous on each fixed-support test space of [F4]. Indeed, for tests supported in a compact , use [F5] to fix finitely many external cutoffs on and internal chart cutoffs on . The external-degree-four coefficient of each localized piece extends by zero in the external coordinates and is integrated on a fixed bounded rectangle . In internal coordinates , differentiation gives : difference quotients converge uniformly on compact coordinate rectangles, by the fundamental theorem of calculus and uniform continuity of the next derivative. Iteration proves smoothness; the bound proves continuity for every output seminorm. Independence of external cutoffs and coordinates follows from [F5] applied at each ; internal coordinate changes act linearly on the retained internal form coefficients, so these local forms glue. Composition with the continuous internal current therefore makes a current in [F4]. Applying the same finite-chart Fubini calculation to an arbitrary test gives : only external degree four contributes, and its interchange with has sign . Integration over also gives a continuous functional on each fixed-support space, since its pullback integral is bounded by finitely many coefficient seminorms on charts of the compact set ; here is closed because is compact. Thus the source pairing defines a current as well.
In the mathematical current convention, the associated current of the degree-three source form is evaluated with the form-current order . Moving the degree-three current past the degree-seven test form changes sign by . The source convention in the Statement therefore gives By [F1], the final term is .
For an internal degree- current , the definition above and give , hence . For the differential assertion let and . Since for a top form on the four-manifold and [F3] gives , the compact-test differential [F4] on and the compact-base differential [F1] on yield This proves the reduction of the current differential on the tests needed for a product compactification.
Remarks
The minus sign is forced by the degree-current convention: the source literature writes the localized source by the test-first wedge , while De Rham currents of compact oriented source cycles associates smooth forms by . A physical source-current postulate in the first convention therefore reduces to in the second. This is the sign conversion used by the massive IIA tadpole item; it is independent of the regularized source-first intersection sign.