{ "id": "2208.12247", "version": "v1", "published": "2022-08-25T17:47:57.000Z", "updated": "2022-08-25T17:47:57.000Z", "title": "Chabauty limits of groups of involutions in $SL(2,F)$ for local fields", "authors": [ "Corina Ciobotaru", "Arielle Leitner" ], "comment": "2 figures, 23 pages", "categories": [ "math.GR", "math.GT" ], "abstract": "We classify Chabauty limits of groups fixed by various (abstract) involutions over $SL(2,F)$, where $F$ is a finite field-extension of $\\mathbb{Q}_p$, with $p\\neq 2$. To do so, we first classify abstract involutions over $SL(2,F)$ with $F$ a quadratic extension of $\\mathbb{Q}_p$, and prove $p$-adic polar decompositions with respect to various subgroups of $p$-adic $SL_2$. Then we classify Chabauty limits of: $SL(2, F) \\subset SL(2,E)$ where $E$ is a quadratic extension of $F$, of $SL(2, \\mathbb{R}) \\subset SL(2, \\mathbb{C})$, and of $H_\\theta \\subset SL(2,F)$, where $H_\\theta$ is the fixed point group of an $F$-involution $\\theta$ over $SL(2,F)$.", "revisions": [ { "version": "v1", "updated": "2022-08-25T17:47:57.000Z" } ], "analyses": { "keywords": [ "local fields", "classify chabauty limits", "quadratic extension", "first classify abstract involutions", "adic polar decompositions" ], "note": { "typesetting": "TeX", "pages": 23, "language": "en", "license": "arXiv", "status": "editable" } } }