The search session has expired. Please query the service again.
The search session has expired. Please query the service again.
The search session has expired. Please query the service again.
The search session has expired. Please query the service again.
We introduce a 1-cocycle on the group of diffeomorphisms Diff(M) of a smooth manifold M endowed with a projective connection. This cocycle represents a nontrivial cohomology class of Diff(M) related to the Diff(M)-modules of second order linear differential operators on M. In the one-dimensional case, this cocycle coincides with the Schwarzian derivative, while, in the multi-dimensional case, it represents its natural and new generalization. This work is a continuation of [3] where the same problems...
We study the cohomology of the group consisting of all -diffeomorphisms of the line, which are -flat to the identity at the origin. We construct non-trivial two second real cohomology classes and uncountably many second integral homology classes of this group.
We prove that the space of orientation preserving homeomorphisms of the 2-sphere which fix pointwise a nontrivial nonseparating continuum is a contractible absolute neighborhood retract homeomorphic to the separable Hilbert space .
Il est démontré que le groupe des difféomorphismes du tore qui sont isotopes à l’identité est un groupe qui est égal à son groupe des commutateurs. Il résulte de D.A.B. Epstein que c’est un groupe simple. Un lemme fondamental est utilisé ; il donne la structure locale des orbites de certaines translations du tore ; ce lemme est une application du théorème des fonctions implicites de F. Sergeraert.
Currently displaying 1 –
16 of
16