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arXiv · 1509.04248

Wild ramification kinks

Andrew Obus·Stefan Wewers
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Abstract

Given a branched cover $f:Y\to X$ between smooth projective curves over a non-archimedian mixed-characteristic local field and an open rigid disk $D\subset X$, we study the question under which conditions the inverse image $f^{-1}(D)$ is again an open disk. More generally, if the cover $f$ varies in an analytic family, is this true at least for some member of the family? Our main result gives a criterion for this to happen.

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Andrew Obus, Stefan Wewers. 2015-09-14. Wild ramification kinks. https://arxiv.org/abs/1509.04248

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