{"title":"具有有理j不变量的非cm椭圆曲线素数域上的等同性度","authors":"Ivan Novak","doi":"10.1016/j.jnt.2025.05.007","DOIUrl":null,"url":null,"abstract":"<div><div>Let <em>E</em> be a non-CM elliptic curve with rational <em>j</em>-invariant. Mazur and Kenku determined all possible degrees of rational cyclic isogenies that <em>E</em> could have. One possible way of generalizing this would be to classify all possible degrees of cyclic isogenies defined over number fields of some fixed degree <span><math><mi>d</mi><mo>></mo><mn>1</mn></math></span>.</div><div>We determine all possible degrees of cyclic isogenies of non-CM elliptic curves with rational <em>j</em>-invariant over number fields of degree <em>p</em>, where <em>p</em> is an odd prime. The analogous classification for quadratic number fields was done by Vukorepa, and this paper completes the classification in case when the degree of the number field is prime.</div><div>To prove the result, we make use of known results on Galois images of rational elliptic curves. In particular, when solving the cubic case, we use the database of images of 2-adic Galois representations which is due to Rouse and Zureick-Brown.</div></div>","PeriodicalId":50110,"journal":{"name":"Journal of Number Theory","volume":"278 ","pages":"Pages 694-714"},"PeriodicalIF":0.7000,"publicationDate":"2025-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Degrees of isogenies over prime degree number fields of non-CM elliptic curves with rational j-invariant\",\"authors\":\"Ivan Novak\",\"doi\":\"10.1016/j.jnt.2025.05.007\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Let <em>E</em> be a non-CM elliptic curve with rational <em>j</em>-invariant. Mazur and Kenku determined all possible degrees of rational cyclic isogenies that <em>E</em> could have. One possible way of generalizing this would be to classify all possible degrees of cyclic isogenies defined over number fields of some fixed degree <span><math><mi>d</mi><mo>></mo><mn>1</mn></math></span>.</div><div>We determine all possible degrees of cyclic isogenies of non-CM elliptic curves with rational <em>j</em>-invariant over number fields of degree <em>p</em>, where <em>p</em> is an odd prime. The analogous classification for quadratic number fields was done by Vukorepa, and this paper completes the classification in case when the degree of the number field is prime.</div><div>To prove the result, we make use of known results on Galois images of rational elliptic curves. In particular, when solving the cubic case, we use the database of images of 2-adic Galois representations which is due to Rouse and Zureick-Brown.</div></div>\",\"PeriodicalId\":50110,\"journal\":{\"name\":\"Journal of Number Theory\",\"volume\":\"278 \",\"pages\":\"Pages 694-714\"},\"PeriodicalIF\":0.7000,\"publicationDate\":\"2025-06-18\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Number Theory\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0022314X25001672\",\"RegionNum\":3,\"RegionCategory\":\"数学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"MATHEMATICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Number Theory","FirstCategoryId":"100","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0022314X25001672","RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MATHEMATICS","Score":null,"Total":0}
Degrees of isogenies over prime degree number fields of non-CM elliptic curves with rational j-invariant
Let E be a non-CM elliptic curve with rational j-invariant. Mazur and Kenku determined all possible degrees of rational cyclic isogenies that E could have. One possible way of generalizing this would be to classify all possible degrees of cyclic isogenies defined over number fields of some fixed degree .
We determine all possible degrees of cyclic isogenies of non-CM elliptic curves with rational j-invariant over number fields of degree p, where p is an odd prime. The analogous classification for quadratic number fields was done by Vukorepa, and this paper completes the classification in case when the degree of the number field is prime.
To prove the result, we make use of known results on Galois images of rational elliptic curves. In particular, when solving the cubic case, we use the database of images of 2-adic Galois representations which is due to Rouse and Zureick-Brown.
期刊介绍:
The Journal of Number Theory (JNT) features selected research articles that represent the broad spectrum of interest in contemporary number theory and allied areas. A valuable resource for mathematicians, the journal provides an international forum for the publication of original research in this field.
The Journal of Number Theory is encouraging submissions of quality, long articles where most or all of the technical details are included. The journal now considers and welcomes also papers in Computational Number Theory.
Starting in May 2019, JNT will have a new format with 3 sections:
JNT Prime targets (possibly very long with complete proofs) high impact papers. Articles published in this section will be granted 1 year promotional open access.
JNT General Section is for shorter papers. We particularly encourage submission from junior researchers. Every attempt will be made to expedite the review process for such submissions.
Computational JNT . This section aims to provide a forum to disseminate contributions which make significant use of computer calculations to derive novel number theoretic results. There will be an online repository where supplementary codes and data can be stored.