Liftable D_4-Covers

Louis Hugo Brewis

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arXiv · 0708.3952

Liftable D_4-Covers

Louis Hugo Brewis

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Abstract

Let k be an algebraically closed field of characteristic p and let G be a subgroup of Aut(k[[t]]) be a faithful action on a local power series ring over k. Let R be a discrete valuation ring of characteristic 0 with residue field k. One asks, whether it is possible to find a faithful action G inside Aut(R[[t]]) which reduces to the given action, i.e. a lift to characteristic 0. We show that liftable actions exists in the case that G = D_4 and p = 2. In fact we introduce a family, the supersimple D_4 -actions, which can always be lifted to characteristic 0.

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BibTeX RIS

Louis Hugo Brewis. 2007-08-29. Liftable D_4-Covers. https://arxiv.org/abs/0708.3952

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