{ "id": "2102.01392", "version": "v1", "published": "2021-02-02T09:07:38.000Z", "updated": "2021-02-02T09:07:38.000Z", "title": "$τ$-Tilting modules over one-point extensions by a simple module at a source point", "authors": [ "Hanpeng Gao" ], "comment": "8 pages; accepted by Journal of algebra and its applications", "categories": [ "math.RT" ], "abstract": "Let $B$ be an one-point extension of a finite dimensional $k$-algebra $A$ by a simple $A$-module at a source point $i$. In this paper, we classify the $\\tau$-tilting modules over $B$. Moreover, it is shown that there are equations $$|\\tilt B|=|\\tilt A|+|\\tilt A/\\langle e_i\\rangle|\\quad \\text{and}\\quad |\\stilt B|=2|\\stilt A|+|\\stilt A/\\langle e_i\\rangle|.$$ As a consequence, we can calculate the numbers of $\\tau$-tilting modules and support $\\tau$-tilting modules over linearly Dynkin type algebras whose square radical are zero.", "revisions": [ { "version": "v1", "updated": "2021-02-02T09:07:38.000Z" } ], "analyses": { "subjects": [ "16G20", "16G60" ], "keywords": [ "tilting modules", "source point", "one-point extension", "simple module", "linearly dynkin type algebras" ], "note": { "typesetting": "TeX", "pages": 8, "language": "en", "license": "arXiv", "status": "editable" } } }