Explicit reduction theory for SU(2,1;Z[i])

Dan Yasaki

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arXiv · math/0601071

Explicit reduction theory for SU(2,1;Z[i])

Dan Yasaki

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Abstract

Let Gamma\D be an arithmetic quotient of a symmetric space of non-compact type. A spine D_0 is a Gamma-equivariant deformation retraction of D with dimension equal to the virtual cohomological dimension of Gamma. We explicitly construct a spine for the case of Gamma=SU(2,1;Z[i]). The spine is then used to compute the cohomology of Gamma\D with various local coefficients.

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Dan Yasaki. 2006-01-04. Explicit reduction theory for SU(2,1;Z[i]). https://arxiv.org/abs/math/0601071

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