Nonvanishing cohomology classes on finite groups of Lie type with Coxeter number at most p

David Sprehn

doi:10.1016/j.jpaa.2014.09.006

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arXiv · 1407.3299

Nonvanishing cohomology classes on finite groups of Lie type with Coxeter number at most p

David Sprehn

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Abstract

We prove that the degree $r(2p-3)$ cohomology of any finite group of Lie type over $\mathbb{F}_{p^r}$, with coefficients in characteristic $p$, is nonzero as long as its Coxeter number is at most $p$. We do this by providing a simple explicit construction of a nonzero element.

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BibTeX RIS

David Sprehn. 2014-07-11. Nonvanishing cohomology classes on finite groups of Lie type with Coxeter number at most p. https://doi.org/10.1016/j.jpaa.2014.09.006

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