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arXiv · 2607.25118

A counterexample to a conjecture of Duncan on versal actions

Federico Scavia
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Abstract

We disprove a conjecture of Duncan asserting that versality of a faithful finite group action can be detected on Sylow subgroups. Our counterexample is an action of $(C_7\rtimes C_3)\times C_2$ on a degree-$2$ Del Pezzo surface.

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Federico Scavia. 2026-07-27. A counterexample to a conjecture of Duncan on versal actions. https://arxiv.org/abs/2607.25118

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