{ "id": "1711.05991", "version": "v1", "published": "2017-11-16T09:05:39.000Z", "updated": "2017-11-16T09:05:39.000Z", "title": "On the stable Andreadakis problem", "authors": [ "Jacques Darné" ], "categories": [ "math.AT", "math.GR" ], "abstract": "Let $F\\_n$ be the free group on $n$ generators. Consider the group $IA\\_n$ of automorpisms of $F\\_n$ acting trivially on its abelianization. There are two canonical filtrations on $IA\\_n$: the first one is its lower central series $\\Gamma\\_*$; the second one is the Andreadakis filtration $\\mathcal A\\_*$, defined from the action on $F\\_n$. In this paper, we establish that the canonical morphism between the associated graded Lie rings ${\\mathcal L}(\\Gamma\\_*)$ and ${\\mathcal L}(\\mathcal A\\_*)$ is stably surjective. We then investigate a $p$-restricted version of the Andreadakis problem. A calculation of the Lie algebra of the classical congruence group is also included.", "revisions": [ { "version": "v1", "updated": "2017-11-16T09:05:39.000Z" } ], "analyses": { "keywords": [ "stable andreadakis problem", "lower central series", "andreadakis filtration", "lie algebra", "associated graded lie rings" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }