{ "id": "2305.19969", "version": "v1", "published": "2023-05-31T15:55:09.000Z", "updated": "2023-05-31T15:55:09.000Z", "title": "On the $p$-isogenies of elliptic curves with multiplicative reduction over quadratic fields", "authors": [ "George C. Ţurcaş" ], "comment": "13 pages, comments are welcome!", "categories": [ "math.NT" ], "abstract": "Let $q > 5$ be a prime and $K$ a quadratic number field. In this article we extend a previous result of Najman and the author and prove that if $E/K$ is an elliptic curve with potentially multiplicative reduction at all primes $\\mathfrak q \\mid q$, then $E$ does not have prime isogenies of degree greater than $71$ and different from $q$. As an application to our main result, we present a variant of the asymptotic version of Fermat's Last Theorem over quadratic imaginary fields of class number one.", "revisions": [ { "version": "v1", "updated": "2023-05-31T15:55:09.000Z" } ], "analyses": { "subjects": [ "11G05", "11F80" ], "keywords": [ "elliptic curve", "multiplicative reduction", "quadratic fields", "quadratic imaginary fields", "quadratic number field" ], "note": { "typesetting": "TeX", "pages": 13, "language": "en", "license": "arXiv", "status": "editable" } } }