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arXiv · 0910.1148

Rationality of Three-Dimensional Quotients by Monomial Actions

Ming-chang Kang·Yuri G. Prokhorov
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Abstract

Let $G$ be a finite 2-group and $K$ be a field satisfying that (i) $\fn{char}K\ne 2$, and (ii) $\sqrt{a}\in K$ for any $a\in K$. If $G$ acts on the rational function field $K(x,y,z)$ by monomial $K$-automorphisms, then the fixed field $K(x,y,z)^G$ is rational (= purely transcendental) over $K$. Applications of this theorem will be given.

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Ming-chang Kang, Yuri G. Prokhorov. 2009-10-07. Rationality of Three-Dimensional Quotients by Monomial Actions. https://arxiv.org/abs/0910.1148

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