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arXiv · 1502.02463

On centrality of $K_2$ for Chevalley groups of type $E_l$

Sergey Sinchuk
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Abstract

For a root system $\Phi$ of type $E_l$ and arbitrary commutative ring $R$ we show that the group $K_2(\Phi, R)$ is contained in the centre of the Steinberg group $St(\Phi, R)$. In course of the proof we also demonstrate an analogue of Quillen---Suslin local-global principle for $K_2(\Phi, R)$.

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Sergey Sinchuk. 2015-02-09. On centrality of $K_2$ for Chevalley groups of type $E_l$. https://doi.org/10.1016/j.jpaa.2015.08.003

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