Algebra & Number Theory

The essential dimension of the normalizer of a maximal torus in the projective linear group

Aurel Meyer and Zinovy Reichstein

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Let p be a prime, k a field of characteristic p and N the normalizer of the maximal torus in the projective linear group PGLn. We compute the exact value of the essential dimension edk(N;p) of N at p for every n1.

Article information

Algebra Number Theory, Volume 3, Number 4 (2009), 467-487.

Received: 9 September 2008
Revised: 5 December 2008
Accepted: 19 December 2008
First available in Project Euclid: 20 December 2017

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Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Primary: 11E72: Galois cohomology of linear algebraic groups [See also 20G10]
Secondary: 20D15: Nilpotent groups, $p$-groups 16K20: Finite-dimensional {For crossed products, see 16S35}

essential dimension central simple algebra character lattice finite p-group Galois cohomology


Meyer, Aurel; Reichstein, Zinovy. The essential dimension of the normalizer of a maximal torus in the projective linear group. Algebra Number Theory 3 (2009), no. 4, 467--487. doi:10.2140/ant.2009.3.467.

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