-submodules of finite index of anticyclotomic plus and minus Selmer groups of elliptic curves
arXiv:2003.10301
Abstract
Let be an odd prime and an imaginary quadratic field where splits. Under appropriate hypotheses, Bertolini showed that the Selmer group of a -ordinary elliptic curve over the anticyclotomic -extension of does not admit any proper -submodule of finite index, where is a suitable Iwasawa algebra. We generalize this result to the plus and minus Selmer groups (in the sense of Kobayashi) of -supersingular elliptic curves. In particular, in our setting the plus/minus Selmer groups have -corank one, so they are not -cotorsion. As an application of our main theorem, we prove results in the vein of Greenberg-Vatsal on Iwasawa invariants of -congruent elliptic curves, extending to the supersingular case results for -ordinary elliptic curves due to Hatley-Lei.
19 pages; revision of the previous version, following the referee's suggestions