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arXiv · 2507.02688

The $\mu-$invariant of fine Selmer groups associated to general Drinfeld modules

Hang Chen
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Abstract

Let $F$ be a global function field over the finite field $\mathbb{F}_q$ where $q$ is a prime power and $A$ be the ring of elements in $F$ regular outside $\infty$. Let $\phi$ be an arbitrary Drinfeld module over $F$ For a fixed non-zero prime ideal $\mathfrak{p}$ of $A$, we show that on the constant $\mathbb{Z}_{\textit{p}}-$extension $\mathfrak{F}$ of $F$, the Pontryagin dual of the fine Selmer group associated to the $\mathfrak{p}-$primary torsion of $\phi$ over $\mathfrak{F}$ is a finitely generated Iwasawa module such that its Iwasawa $\mu-$invariant vanishes. This provides a generalization of the results given in arXiv:2311.06499.

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Hang Chen. 2025-07-03. The $\mu-$invariant of fine Selmer groups associated to general Drinfeld modules. https://arxiv.org/abs/2507.02688

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