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arXiv · 0910.1816

The Néron component series of an abelian variety

Lars Halvard Halle·Johannes Nicaise
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Abstract

We introduce the Néron component series of an abelian variety $A$ over a complete discretely valued field. This is a power series in $\Z[[T]]$, which measures the behaviour of the number of components of the Néron model of $A$ under tame ramification of the base field. If $A$ is tamely ramified, then we prove that the Néron component series is rational. It has a pole at T=1, whose order equals one plus the potential toric rank of $A$. This result is a crucial ingredient of our proof of the motivic monodromy conjecture for abelian varieties. We expect that it extends to the wildly ramified case; we prove this if $A$ is an elliptic curve, and if $A$ has potential purely multiplicative reduction.

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Lars Halvard Halle, Johannes Nicaise. 2009-10-09. The Néron component series of an abelian variety. https://arxiv.org/abs/0910.1816

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