On non-trivial $\Lambda$-submodules with finite index of the plus/minus Selmer group over anticyclotomic ${\mathbb{Z}}_p$-extension at inert primes

Abstract

Let $K$ be an imaginary quadratic field where $p$ is inert. Let $E$ be an elliptic curve defined over $K$ and suppose that $E$ has good supersingular reduction at $p$. In this paper, we prove that the plus/minus Selmer group of $E$ over the anticyclotomic ${\mathbb{Z}}_p$-extension of $K$ has no non-trivial $\Lambda$-submodules of finite index under mild assumptions for $E$. This is an analogous result to R. Greenberg and B. D. Kim for the anticyclotomic ${\mathbb{Z}}_p$-extension essentially. By applying the results of A. Agboola--B. Howard or A. Burungale--K. Büyükboduk--A. Lei, we can also construct examples satisfying the assumptions of our theorem.