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arXiv · 1502.05092

Representation spaces for central extensions and almost commuting unitary matrices

Alejandro Adem·Man Chuen Cheng
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Abstract

Let $\Gamma$ denote a central extension of the form $1\to \mathbb{Z}^r\to\Gamma\to \mathbb{Z}^n\to 1$. In this paper we describe the topology of the spaces of homomorphisms $\text{Hom}(\Gamma, U(m))$ and the associated moduli spaces $\text{Rep}(\Gamma, U(m))$, where $U(m)$ is the group of $m\times m$ unitary matrices.

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Alejandro Adem, Man Chuen Cheng. 2015-02-18. Representation spaces for central extensions and almost commuting unitary matrices. https://doi.org/10.1112/jlms/jdw046

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