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arXiv · 1307.5724

Pseudo-reflection groups and essential dimension

Alexander Duncan·Zinovy Reichstein
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Abstract

We give a simple formula for the essential dimension of a finite pseudo-reflection group at a prime p and determine the absolute essential dimension for most irreducible pseudo-reflection groups. We also study the "poor man's essential dimension" of an arbitrary finite group, an intermediate notion between the absolute essential dimension and the essential dimension at a prime p.

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Alexander Duncan, Zinovy Reichstein. 2013-07-22. Pseudo-reflection groups and essential dimension. https://doi.org/10.1112/jlms%2Fjdu056

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