{ "id": "2105.09731", "version": "v1", "published": "2021-05-20T13:31:38.000Z", "updated": "2021-05-20T13:31:38.000Z", "title": "Free limits of free algebras", "authors": [ "Alexandru Chirvasitu", "Tao Hong" ], "comment": "11 pages", "categories": [ "math.RA", "math.CT" ], "abstract": "Consider a diagram $\\cdots \\to F_3 \\to F_2\\to F_1$ of algebraic systems, where $F_n$ denotes the free object on $n$ generators and the connecting maps send the extra generator to some distinguished trivial element. We prove that (a) if the $F_i$ are free associative algebras over a fixed field then the limit in the category of graded algebras is again free on a set of homogeneous generators; (b) on the other hand, the limit in the category of associative (ungraded) algebras is a free formal power series algebra on a set of homogeneous elements, and (c) if the $F_i$ are free Lie algebras then the limit in the category of graded Lie algebras is again free.", "revisions": [ { "version": "v1", "updated": "2021-05-20T13:31:38.000Z" } ], "analyses": { "subjects": [ "08B20", "16S10", "16W50", "17B01", "17B70" ], "keywords": [ "free algebras", "free limits", "free formal power series algebra", "free lie algebras", "distinguished trivial element" ], "note": { "typesetting": "TeX", "pages": 11, "language": "en", "license": "arXiv", "status": "editable" } } }