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arXiv · 1602.01596

The local lifting problem for A_4

Andrew Obus
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Abstract

We solve the local lifting problem for the alternating group A_4, thus showing that it is a local Oort group. Specifically, if k is an algebraically closed field of characteristic 2, we prove that every A_4-extension of k[[s]] lifts to characteristic zero. As a consequence, every A_4-branched cover of smooth projective curves in characteristic 2 lifts to characteristic zero.

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Andrew Obus. 2016-02-04. The local lifting problem for A_4. https://doi.org/10.2140/ant.2016.10.1683

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