English

A Note on the Growth of Sha in Dihedral Extensions

Number Theory 2024-11-26 v1

Abstract

We provide a formula for the order of the Tate--Shafarevich group of elliptic curves over dihedral extensions of number fields of order 2n2n, up to 4th4^{th} powers and primes dividing nn. Specifically, for odd nn it is equal to the order of the Tate--Shafarevich group over the quadratic subextension. A similar formula holds for even nn.

Keywords

Cite

@article{arxiv.2411.15663,
  title  = {A Note on the Growth of Sha in Dihedral Extensions},
  author = {Jamie Bell},
  journal= {arXiv preprint arXiv:2411.15663},
  year   = {2024}
}