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arXiv · 2006.13574

A braid-like presentation of the integral Steinberg group of type $C_2$

Christian Kassel
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Abstract

We show that the Steinberg group $\text{St}(C_2,{\mathbb Z})$ associated with the Lie type $C_2$ and with integer coefficients can be realized as a quotient of the braid group $B_6$ by one relation. As an application we give a new braid-like presentation of the symplectic modular group $\text{Sp}_4({\mathbb Z})$.

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Christian Kassel. 2020-06-24. A braid-like presentation of the integral Steinberg group of type $C_2$. https://doi.org/10.1016/j.jalgebra.2020.09.015

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