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Essential p-dimension of the normalizer of a maximal torus

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Abstract

We compute the exact value of the essential p-dimension of the normalizer of a split maximal torus for most simple connected linear algebraic groups. These values give new upper bounds on the essential p-dimension of some simple groups, including some exceptional groups. For each connected simple algebraic group, we also give an upper bound on the essential p-dimension of any torus contained in that group. These results are achieved by a detailed case-by-case analysis.

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Correspondence to Mark L. MacDonald.

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Partially supported by an NSERC Postdoctoral Fellowship. (Mark L. MacDonald)

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MacDonald, M.L. Essential p-dimension of the normalizer of a maximal torus. Transformation Groups 16, 1143–1171 (2011). https://doi.org/10.1007/s00031-011-9157-2

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