{"paper":{"title":"Elliptic points of the Drinfeld modular groups","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["math.NT"],"primary_cat":"math.GR","authors_text":"Andreas Schweizer, A. W. Mason","submitted_at":"2013-08-20T04:37:58Z","abstract_excerpt":"Let $K$ be an algebraic function field with constant field ${\\mathbb F}_q$. Fix a place $\\infty$ of $K$ of degree $\\delta$ and let $A$ be the ring of elements of $K$ that are integral outside $\\infty$. We give an explicit description of the elliptic points for the action of the Drinfeld modular group $G=GL_2(A)$ on the Drinfeld's upper half-plane $\\Omega$ and on the Drinfeld modular curve $G\\!\\setminus\\!\\Omega$. It is known that under the {\\it building map} elliptic points are mapped onto vertices of the {\\it Bruhat-Tits tree} of $G$. We show how such vertices can be determined by a simple con"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1308.4229","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}