Matui's AH conjecture for Graph Groupoids

Petter Nyland; Eduard Ortega

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arXiv · 2003.14055

Matui's AH conjecture for Graph Groupoids

Petter Nyland·Eduard Ortega

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Abstract

We prove that Matui's AH conjecture holds for graph groupoids of infinite graphs. This is a conjecture which relates the topological full group of an ample groupoid with the homology of the groupoid. Our main result complements Matui's result in the finite case, which makes the AH conjecture true for all graph groupoids covered by the assumptions of said conjecture. Furthermore, we observe that for arbitrary graphs, the homology of a graph groupoid coincides with the $K$-theory of its groupoid $C^*$-algebra.

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Petter Nyland, Eduard Ortega. 2020-03-31. Matui's AH conjecture for Graph Groupoids. https://arxiv.org/abs/2003.14055

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