English

Control Theorems for l-adic Lie extensions of global function fields

Number Theory 2013-04-05 v2

Abstract

Let F be a global function field of characteristic p>0, K/F an l-adic Lie extension unramified outside a finite set of places S and A/F an abelian variety without complex multiplication. We study Sel_A(K)_l^\vee (the Pontrjagin dual of the Selmer group) and (under some mild hypotheses) prove that it is a finitely generated Z_l[[\Gal(K/F)]]-module via generalizations of Mazur's Control Theorem. If Gal(K/F) has no elements of order l and contains a closed normal subgroup H such that Gal(K/F)/H\simeq Z_l, we are able to give sufficient conditions for Sel_A(K)_l^\vee to be finitely generated as Z_l[[H]]-module and, consequently, a torsion Z_l[[\Gal(K/F)]]-module. We deal with both cases l\neq p and l=p.

Keywords

Cite

@article{arxiv.1206.2767,
  title  = {Control Theorems for l-adic Lie extensions of global function fields},
  author = {Andrea Bandini and Maria Valentino},
  journal= {arXiv preprint arXiv:1206.2767},
  year   = {2013}
}

Comments

21 pages, revised arguments in sections 2 and 4

R2 v1 2026-06-21T21:18:31.514Z