# Non-abelian extensions of infinite-dimensional Lie groups

@article{Neeb2005NonabelianEO, title={Non-abelian extensions of infinite-dimensional Lie groups}, author={Karl-Hermann Neeb}, journal={arXiv: Group Theory}, year={2005} }

In this paper we study non-abelian extensions of a Lie group $G$ modeled on a locally convex space by a Lie group $N$. The equivalence classes of such extension are grouped into those corresponding to a class of so-called smooth outer actions $S$ of $G$ on $N$. If $S$ is given, we show that the corresponding set $\Ext(G,N)_S$ of extension classes is a principal homogeneous space of the locally smooth cohomology group $H^2_{ss}(G,Z(N))_S$. To each $S$ a locally smooth obstruction class $\chi(S… Expand

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