The Néron component series of an abelian variety
arXiv:0910.1816
Abstract
We introduce the Néron component series of an abelian variety over a complete discretely valued field. This is a power series in , which measures the behaviour of the number of components of the Néron model of under tame ramification of the base field. If 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 . 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 is an elliptic curve, and if has potential purely multiplicative reduction.