On the structure of the module of Euler systems for a $p$-adic representation

TL;DR

This paper explores the structure of Euler systems for p-adic representations, providing a classification criterion under certain conjectures and applying it to the multiplicative group over number fields.

Contribution

It introduces an Iwasawa-theoretic classification criterion for Euler systems and verifies it in many cases, advancing understanding of their structure.

Findings

Established a classification criterion for Euler systems under weak Leopoldt conjecture.

Provided evidence supporting a refined question on Euler systems related to Coleman's conjecture.

Explicitly described the structure of Euler systems for the multiplicative group over number fields.

Abstract

We investigate a question of Burns and Sano concerning the structure of the module of Euler systems for a general $p$-adic representation. Assuming the weak Leopoldt conjecture, and the vanishing of $\mu$-invariants of natural Iwasawa modules, we obtain an Iwasawa-theoretic classification criterion for Euler systems which can be used to study this module. This criterion, taken together with Coleman's conjecture on circular distributions, leads us to pose a refinement of the aforementioned question for which we provide strong, and unconditional, evidence. We furthermore answer this question in the affirmative in many interesting cases in the setting of the multiplicative group over number fields. As a consequence of these results, we derive explicit descriptions of the structure of the full collection of Euler systems for the situations in consideration.