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The local lifting problem for dihedral groups

Irene I. Bouw·Stefan Wewers
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Abstract

Let $G=D_p$ be the dihedral group of order $2p$, where $p$ is an odd prime. Let $k$ an algebraically closed field of characteristic $p$. We show that any action of $G$ on the ring $k[[y]]$ can be lifted to an action on $R[[y]]$, where $R$ is some complete discrete valuation ring with residue field $k$ and fraction field of characteristic 0.

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Irene I. Bouw, Stefan Wewers. 2004-09-27. The local lifting problem for dihedral groups. https://arxiv.org/abs/math/0409395

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