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arXiv · 0910.5574

Essential p-dimension of algebraic tori

Roland Lötscher·Mark MacDonald·Aurel Meyer·Zinovy Reichstein
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Abstract

The essential dimension is a numerical invariant of an algebraic group G which may be thought of as a measure of complexity of G-torsors over fields. A recent theorem of N. Karpenko and A. Merkurjev gives a simple formula for the essential dimension of a finite p-group. We obtain similar formulas for the essential p-dimension of a broader class of groups, which includes all algebraic tori.

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Roland Lötscher, Mark MacDonald, Aurel Meyer, Zinovy Reichstein. 2009-10-29. Essential p-dimension of algebraic tori. https://arxiv.org/abs/0910.5574

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