On Selmer groups of abelian varieties over $\ell$-adic Lie extensions of global function fields

Abstract

Let $F$ be a global function field of characteristic $p>0$ and $A/F$ an abelian variety. Let $K/F$ be an $\l$-adic Lie extension ($\l\neq p$) unramified outside a finite set of primes $S$ and such that $\Gal(K/F)$ has no elements of order $\l$. We shall prove that, under certain conditions, $Sel_A(K)_\l^\vee$ has no nontrivial pseudo-null submodule.