English

2-descent for Bloch--Kato Selmer groups and rational points on hyperelliptic curves II

Number Theory 2024-03-13 v1

Abstract

We give refined methods for proving finiteness of the Chabauty--Coleman--Kim set X(Q2)2X(\mathbb{Q}_2 )_2 , when XX is a hyperelliptic curve with a rational Weierstrass point. The main developments are methods for computing Selmer conditions at 22 and \infty for the mod 2 Bloch--Kato Selmer group associated to the higher Chow group CH2(Jac(X),1)\mathrm{CH}^2 (\mathrm{Jac}(X),1). As a result we show that most genus 2 curves in the LMFDB of Mordell--Weil rank 2 with exactly one rational Weierstrass point satsify #X(Q2)2<\# X(\mathbb{Q}_2 )_2 <\infty . We also obtain a field-theoretic description of second descent on the Jacobian of a hyperelliptic curve (under some conditions).

Keywords

Cite

@article{arxiv.2403.07476,
  title  = {2-descent for Bloch--Kato Selmer groups and rational points on hyperelliptic curves II},
  author = {Netan Dogra},
  journal= {arXiv preprint arXiv:2403.07476},
  year   = {2024}
}

Comments

29 pages. Comments welcome!