%0 Journal Article
%T Trace formula for component groups of N¨Śron models
%A Johannes Nicaise
%J Mathematics
%D 2009
%I arXiv
%X We study a trace formula for tamely ramified abelian varieties $A$ over a complete discretely valued field, which expresses the Euler characteristic of the special fiber of the N\'eron model of $A$ in terms of the Galois action on the $\ell$-adic cohomology of $A$. If $A$ has purely additive reduction, the trace formula yields a cohomological interpretation for the number of connected components of the special fiber of the N\'eron model.
%U http://arxiv.org/abs/0901.1809v2