{ "id": "2306.02493", "version": "v1", "published": "2023-06-04T22:00:20.000Z", "updated": "2023-06-04T22:00:20.000Z", "title": "Galois representations with large image in global Langlands correspondence", "authors": [ "Adrian Zenteno" ], "comment": "This article supersedes arXiv:2008.00556", "categories": [ "math.NT", "math.GR" ], "abstract": "The global Langlands conjecture for $\\text{GL}_n$ over a number field $F$ predicts a correspondence between certain algebraic automorphic representations $\\pi$ of $\\text{GL}_n(\\mathbb{A}_F)$ and certain families $\\{ \\rho_{\\pi,\\ell} \\}_\\ell$ of $n$-dimensional $\\ell$-adic Galois representations of $\\text{Gal}(\\overline{F}/F)$. In general, it is expected that the image of the residual Galois representations $\\overline{\\rho}_{\\pi,\\ell}$ of the $\\rho_{\\pi,\\ell}$'s should be as large as possible for almost all primes $\\ell$, unless there is an automorphic reason for it does not happen. In this paper, we study the images of certain compatible systems of Galois representations $\\{\\rho_{\\pi,\\ell} \\}_\\ell$ associated to regular algebraic, polarizable, cuspidal automorphic representations $\\pi$ of $\\text{GL}_n(\\mathbb{A}_F)$ by using only standard techniques and currently available tools (e.g., Fontaine-Laffaille theory, Serre's modularity conjecture, classification of the maximal subgroups of Lie type groups, and known results about irreducibility of automorphic Galois representations and Langlands functoriality). In particular, when $F$ is a totally real field and $n$ is an odd prime number $\\leq 393$, we prove that (under certain automorphic conditions) the images of the residual representations $\\overline{\\rho}_{\\pi,\\ell}$ are as large as possible for infinitely many primes $\\ell$. In fact, we prove the large image conjecture (i.e. large image for almost all primes $\\ell$) when $F=\\mathbb{Q}$ and $n=5$.", "revisions": [ { "version": "v1", "updated": "2023-06-04T22:00:20.000Z" } ], "analyses": { "subjects": [ "11F80", "11F70", "20G40", "20G41" ], "keywords": [ "global langlands correspondence", "cuspidal automorphic representations", "odd prime number", "automorphic galois representations", "lie type groups" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }