{ "id": "2103.04927", "version": "v1", "published": "2021-03-08T17:39:30.000Z", "updated": "2021-03-08T17:39:30.000Z", "title": "Realization of a Lie algebra and classifying space of crossed modules", "authors": [ "Yves Félix", "Daniel Tanré" ], "categories": [ "math.AT" ], "abstract": "Complete differential graded Lie algebras appear to be a wonderful tool for giving nice algebraic models for the rational homotopy type of non-simply connected spaces. In particular, there is a realization functor of any Lie algebra as a simplicial set. In a previous work, we considered the particular case of a complete graded Lie algebra, $L$, concentrated in degree 0 and proved that its geometric realization is isomorphic to the usual bar construction on the Malcev group associated to $L$. Here we consider the case of a complete differential graded Lie algebra, $L$, concentrated in degrees 0 and 1. We first establish that $L$ has the structure of a crossed module and prove that the geometric realization of $L$ is isomorphic to the simplicial classifying space of this crossed module.", "revisions": [ { "version": "v1", "updated": "2021-03-08T17:39:30.000Z" } ], "analyses": { "subjects": [ "55P62", "17B55", "55U10" ], "keywords": [ "crossed module", "complete differential graded lie algebra", "classifying space", "differential graded lie algebras appear", "geometric realization" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }