Characteristic ideals and Selmer groups

Andrea Bandini; Francesc Bars; Ignazio Longhi

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arXiv · 1404.2788

Characteristic ideals and Selmer groups

Andrea Bandini·Francesc Bars·Ignazio Longhi

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Abstract

Let $A$ be an abelian variety defined over a global field $F$ of positive characteristic $p$ and let $\calf/F$ be a $\Z_p^{\N}$-extension, unramified outside a finite set of places of $F$. Assuming that all ramified places are totally ramified, we define a pro-characteristic ideal associated to the Pontrjagin dual of the $p$-primary Selmer group of $A$, in order to formulate an Iwasawa Main Conjecture for the non-noetherian commutative Iwasawa algebra $\Z_p[[\Gal(\calf/F)]]$ (which we also prove for a constant abelian variety). To do this we first show the relation between the characteristic ideals of duals of Selmer groups for a $\Z_p^d$-extension $\calf_d/F$ and for any $\Z_p^{d-1}$-extension contained in $\calf_d\,$, and then use a limit process.

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Andrea Bandini, Francesc Bars, Ignazio Longhi. 2014-07-21. Characteristic ideals and Selmer groups. https://arxiv.org/abs/1404.2788

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