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Essential dimension: a survey

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In the paper we survey research on the essential dimension. The highlights of the survey are the computations of the essential dimensions of finite groups, groups of multiplicative type and the spinor groups. We present self-contained proofs of these cases and give applications in the theory of simple algebras and quadratic forms.

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Correspondence to Alexander S. Merkurjev.

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*The work has been supported by the NSF grant DMS #1160206.

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Merkurjev, A.S. Essential dimension: a survey. Transformation Groups 18, 415–481 (2013). https://doi.org/10.1007/s00031-013-9216-y

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