Let $E$ be an elliptic curve over $\mathbb Q$ which has good supersingular
reduction at $p\gt 3$. We construct what we call the $\pm/\pm$-Selmer
groups of $E$ over the $\mathbb Z_p^2$-extension of an imaginary quadratic
field $K$ when the prime $p$ splits completely over $K/\mathbb Q$, and
prove they enjoy a property analogous to Mazur's control theorem.
Furthermore, we propose a conjectural connection between the
$\pm/\pm$-Selmer groups and Loeffler's two-variable $\pm/\pm$-$p$-adic
$L$-functions of elliptic curves.
elliptic curves, Iwasawa theory
11Gxx - Arithmetic algebraic geometry (Diophantine geometry) [See also 11Dxx, 14Gxx, 14Kxx]