{ "id": "2211.13458", "version": "v1", "published": "2022-11-24T07:52:59.000Z", "updated": "2022-11-24T07:52:59.000Z", "title": "On the stable cohomology of $\\mathrm{GL}(n, \\mathbb{Z})$, $\\mathrm{Aut}(F_n)$ and $\\mathrm{IA}_n$", "authors": [ "Kazuo Habiro", "Mai Katada" ], "comment": "47 pages", "categories": [ "math.AT", "math.GR" ], "abstract": "Borel's stability and vanishing theorem gives the stable cohomology of $\\mathrm{GL}(n,\\mathbb{Z})$ with coefficients in algebraic $\\mathrm{GL}(n,\\mathbb{Z})$-representations. We improve the stable range in two ways by using ideas of Borel and Kupers-Miller-Patzt. By combining the improved Borel theorem with the Hochschild-Serre spectral sequence, we compute the twisted first cohomology of the automorphism group $\\mathrm{Aut}(F_n)$ of the free group $F_n$ of rank $n$. We also study the stable rational cohomology of the IA-automorphism group $\\mathrm{IA}_n$ of $F_n$. We propose a conjectural algebraic structure of the stable rational cohomology of $\\mathrm{IA}_n$, and consider some relations to known results and conjectures. We also consider a conjectural structure of the stable rational cohomology of the Torelli groups of surfaces.", "revisions": [ { "version": "v1", "updated": "2022-11-24T07:52:59.000Z" } ], "analyses": { "subjects": [ "20F28", "20J06" ], "keywords": [ "stable cohomology", "stable rational cohomology", "conjectural algebraic structure", "hochschild-serre spectral sequence", "borels stability" ], "note": { "typesetting": "TeX", "pages": 47, "language": "en", "license": "arXiv", "status": "editable" } } }