English

Tamagawa numbers of elliptic curves with torsion points

Number Theory 2022-02-15 v1

Abstract

Let KK be a global field and let E/KE/K be an elliptic curve with a KK-rational point of prime order pp. In this paper we are interested in how often the (global) Tamagawa number c(E/K)c(E/K) of E/KE/K is divisible by pp. This is a natural question to consider in view of the fact that the fraction c(E/K)/E(K)torsc(E/K)/ |E(K)_{\text{tors}}| appears in the second part of the Birch and Swinnerton-Dyer Conjecture. We focus on elliptic curves defined over global fields, but we also prove a result for higher dimensional abelian varieties defined over Q\mathbb{Q}.

Keywords

Cite

@article{arxiv.2202.06235,
  title  = {Tamagawa numbers of elliptic curves with torsion points},
  author = {Mentzelos Melistas},
  journal= {arXiv preprint arXiv:2202.06235},
  year   = {2022}
}

Comments

9 pages. Final version. To appear in Archiv der Mathematik