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Essential dimensions of finite groups

Ming-chang Kang
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Abstract

We study the essential dimension of a finite group G over a field K. A generalization of the central extension theorem of Buhler and Reichstein (Compositio Math. 106 (1997) 159-179, Theorem 5.3) is obtained. We also get lower bounds of essential dimension of symmetric groups and alternating groups over field of any characteristic.

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Ming-chang Kang. 2006-11-29. Essential dimensions of finite groups. https://arxiv.org/abs/math/0611673

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