{ "id": "2302.01611", "version": "v1", "published": "2023-02-03T09:21:25.000Z", "updated": "2023-02-03T09:21:25.000Z", "title": "One-quasihomomorphisms from the integers into symmetric matrices", "authors": [ "Tim Seynnaeve", "Nafie Tairi", "Alejandro Vargas" ], "comment": "6 pages, 4 figures, comments welcome", "categories": [ "math.CO", "math.NT" ], "abstract": "A function $f$ from $\\mathbb{Z}$ to the symmetric matrices over an arbitrary field $K$ of characteristic $0$ is a $1$-quasihomomorphism if the matrix $f(x+y) - f(x) - f(y)$ has rank at most $1$ for all $x,y \\in \\mathbb{Z}$. We show that any such $1$-quasihomomorphism has distance at most $2$ from an actual group homomorphism. This gives a positive answer to a special case of a problem posed by Kazhdan and Ziegler.", "revisions": [ { "version": "v1", "updated": "2023-02-03T09:21:25.000Z" } ], "analyses": { "subjects": [ "11B30" ], "keywords": [ "symmetric matrices", "one-quasihomomorphisms", "actual group homomorphism", "arbitrary field", "special case" ], "note": { "typesetting": "TeX", "pages": 6, "language": "en", "license": "arXiv", "status": "editable" } } }