Apartment classes of integral symplectic groups

Abstract

In this note we present an alternative proof of a theorem of Gunnells, which states that the Steinberg module of $\mathrm{S}{\mathrm{p}}_{2n}(\mathbb{Q})$ is a cyclic $\mathrm{S}{\mathrm{p}}_{2n}(\mathbb{Z})$-module, generated by integral apartment classes.

arXiv commentv2: 16 pages. References updated. v3: accepted version, to appear in J. Topol. Anal

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Cited by in corpus (1)

• Connectivity of partial basis complexes of freely decomposable groups