Published online by Cambridge University Press: 29 June 2020
We study the growth of p-primary Selmer groups of abelian varieties with good ordinary reduction at p in ${{Z}}_p$-extensions of a fixed number field K. Proving that in many situations the knowledge of the Selmer groups in a sufficiently large number of finite layers of a
${{Z}}_p$-extension over K suffices for bounding the over-all growth, we relate the Iwasawa invariants of Selmer groups in different
${{Z}}_p$-extensions of K. As applications, we bound the growth of Mordell–Weil ranks and the growth of Tate-Shafarevich groups. Finally, we derive an analogous result on the growth of fine Selmer groups.