Behaviour of the order of Tate-Shafarevich groups for the quadratic twists of elliptic curves
arXiv:1611.07840
Abstract
We present the results of our search for the orders of Tate-Shafarevich groups for the quadratic twists of elliptic curves. We formulate a general conjecture, giving for a fixed elliptic curve over and positive integer , an asymptotic formula for the number of quadratic twists , positive square-free integers less than , with finite group and $|\Sha(E_d(\Bbb Q))| = k^2$. This paper continues the authors previous investigations concerning orders of Tate-Shafarevich groups in quadratic twists of the curve . In section 8 we exhibit examples of rank zero elliptic curves with $|\Sha(E)| > 63408^2$, which was the largest previously known value for any explicit curve. Our record is an elliptic curve with $|\Sha(E)| = 1029212^2$.