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arXiv · 0901.3005

Rational cohomology of an algebra need not be detected by Frobenius kernels

Wilberd van der Kallen
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Abstract

Friedrich Knop has given an example of a polynomial algebra A in characteristic two with an unusual SL_2 action. We exhibit a nontrivial class in H^1(SL_2,A), not detected by Frobenius kernels.

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BibTeXRIS

Wilberd van der Kallen. 2009-01-20. Rational cohomology of an algebra need not be detected by Frobenius kernels. https://arxiv.org/abs/0901.3005

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