Fibered cusp versus -index theory
In this paper we study a new structure, called a spinnable structure, on a differentiable manifold. Roughly speaking, a differentiable manifold is spinnable if it can spin around a codimension 2 submanifold, called the axis, as if the top spins.The main result is the following: let be a compact -connected -dimensional differentiable manifold , then admits a spinnable structure with axis . Making use of the codimension-one foliation on , this yields that admits a codimension-foliation.
On donne une construction de formes de contact sur toute variété décomposable en somme connexe de variétés de contact en toute dimension.