Upper Bounds for the Essential Dimensionof E 7

MacDonald, Mark L.

Canadian mathematical bulletin, Tome 56 (2013) no. 4, pp. 795-800

Résumé

This paper gives a new upper bound for the essential dimension and the essential 2-dimension of the split simply connected group of type ${{E}_{7}}$ over a field of characteristic not 2 or 3. In particular, $\text{ed}\left( {{E}_{7}} \right)\,\le \,29$ , and $\text{ed}\left( {{E}_{7}};\,2 \right)\,\le \,27$ .

Détail

DOI : 10.4153/CMB-2013-006-x

Mots-clés : 20G15, 20G41, E 7, essential dimension, stabilizer in general position

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