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arXiv · 2109.01555

Congruence-simplicity of Steinberg algebras of non-Hausdorff ample groupoids over semifields

Tran Giang Nam·Jens Zumbrägel
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Abstract

We investigate the algebra of an ample groupoid, introduced by Steinberg, over a semifield S. In particular, we obtain a complete characterization of congruence-simpleness for Steinberg algebras of second-countable ample groupoids, extending the well-known characterizations when S is a field. We apply our congruence-simplicity results to tight groupoids of inverse semigroup representations associated to self-similar graphs.

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Tran Giang Nam, Jens Zumbrägel. 2021-09-09. Congruence-simplicity of Steinberg algebras of non-Hausdorff ample groupoids over semifields. https://arxiv.org/abs/2109.01555

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