Submission: 2014, Nov 11
We give a lower bound for the essential dimension of a split simple algebraic group of "adjoint" type over a field of characteristic 2. We also compute the essential dimension of orthogonal and special orthogonal groups in characteristic 2.
2010 Mathematics Subject Classification: 11E04, 11E57, 11E72, secondary 11E81, 14L35, 20G15
Keywords and Phrases: Linear algebraic group, essential dimension, torsor, orthogonal representation, Killing form, quadratic form.
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