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arXiv · 1505.02932

On separating fixed points from zero by invariants

Jonathan Elmer·Martin Kohls
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Abstract

Assume a fixed point v in a G-module V can be separated from zero by a homogeneous invariant of degree dp^r where p>0 is the characteristic of the ground field k and p, d are coprime. We show that then v can also be separated from zero by an invariant of degree p^r , which we obtain explicitly from f. It follows that the minimal degree of a homogeneous invariant separating v from zero is a p-power.

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Jonathan Elmer, Martin Kohls. 2015-05-12. On separating fixed points from zero by invariants. https://doi.org/10.1080/00927872.2016.1175465

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