Manifolds and cell complexes Foliations Example
Reeb foliation
Example
Let be the open unit disc. On consider, for each , the surface These surfaces are disjoint graphs over , and they fill . Together with the boundary cylinder , they form a codimension one foliation of the closed solid cylinder . Each is a plane that bends upwards and approaches the boundary cylinder as , since . The translation maps to , so the foliation passes to the quotient solid torus . This foliated solid torus is a Reeb component. Its boundary torus is one leaf, and every interior leaf is a plane that spirals towards the boundary.
The -sphere is the union of two solid tori glued along their boundary tori. The gluing sends the meridian of each solid torus to the longitude of the other. Putting a Reeb component on each solid torus gives a smooth codimension one foliation of , the Reeb foliation. The leaves are one torus and infinitely many planes.
Remarks
The construction shows that , which has Euler characteristic , carries a codimension one foliation. Novikov proved that every codimension one foliation of class on has a compact leaf, a torus bounding a Reeb component. The torus leaf has infinite fundamental group, so the Reeb stability theorem does not force the other leaves to be compact, and indeed they are planes.
Further reading
About this page
| Tag | W58NYR1DGR |
|---|---|
| URI | m2://W58NYR1DGR |
| Kind | example |
| Writing | W0 stub |
| MSC | 57R30, 53C12 |
| Instance of | Foliation |
| Same as | |
| Changed | 2 November 2026 |
Markdown · JSON · Edit on GitHub
What this page needs for W1
- a source with a locator (0 of 1)
The writing levels say how complete the text of a page is. They do not measure its truth.
What links here
No page links to this page yet.