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.
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- 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.
Taut codimension-one foliations
Definition
Assume Countable Choice . Let be a codimension-one regular foliation of a smooth manifold , transversely oriented in this pair. is taut if for every leaf of there is a closed transversal through : an embedded smooth loop , everywhere transverse to , with . The empty manifold is taut vacuously, but has no closed transversal. On a nonempty compact connected , the leaf-by-leaf condition is equivalent to the existence of a single closed transversal meeting every leaf, as proved in A taut foliation of a compact connected manifold has a single closed transversal ↗. For a closed oriented three-manifold the sufficient closed-two-form criterion is A leafwise positive closed two-form calibrates a taut foliation ↗; that three-dimensional criterion is not asserted here in other dimensions.
Depends on
- Smooth maps transverse to a regular foliation
- Leaves of a regular foliation
- Smooth embeddings
- Embedded submanifolds and slice charts
- Open cover, subcover, and compact topological space; a compact subset is a subspace that is compact in its own right
- Separation of a topological space, connected and disconnected spaces, clopen sets, and connected subsets
- The countable-choice principle used in the foliation pair
Used by
- A fibre foliation of a mapping torus is taut Example
- The Reeb foliation of the three-sphere is not taut Example
- A foliation is taut if and only if it has no dead-end component Lemma
- A no-transversal leaf bounds a positive accessibility region with finite inward boundary Lemma
- A Reeb component obstructs tautness Lemma
- A taut foliation of a compact connected manifold has a single closed transversal Lemma
- A leafwise positive closed two-form calibrates a taut foliation Proposition
- A transverse volume-preserving flow implies tautness in the compact cooriented three-dimensional setting Proposition
Dependency tree · two levels
28 results within two dependency steps of this one, each drawn at its shortest distance from it. An arrow runs from a result to what uses it, so the chart reads left to right and ends at this result, which carries a heavier outline. Every node is a link to that result. Click elsewhere on the chart to enlarge it.
Sources
- Danny Calegari, Foliations and the Geometry of 3-Manifolds (Oxford Mathematical Monographs; complete author-hosted PDF) (standard reference, not scraped)