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arXiv · 0806.3743

Regularity conditions for arbitrary Leavitt path algebras

G. Abrams·K. M. Rangaswamy
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Abstract

We show that if $E$ is an arbitrary acyclic graph then the Leavitt path algebra $L_K(E)$ is locally $K$-matricial; that is, $L_K(E)$ is the direct union of subalgebras, each isomorphic to a finite direct sum of finite matrix rings over the field $K$. As a consequence we get our main result, in which we show that the following conditions are equivalent for an arbitrary graph $E$: (1) $L_K(E)$ is von Neumann regular. (2) $L_K(E)$ is $π$-regular. (3) $E$ is acyclic. (4) $L_K(E)$ is locally $K$-matricial. (5) $L_K(E)$ is strongly $π$-regular. We conclude by showing how additional regularity conditions (unit regularity, strongly clean) can be appended to this list of equivalent conditions.

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G. Abrams, K. M. Rangaswamy. 2008-10-05. Regularity conditions for arbitrary Leavitt path algebras. https://arxiv.org/abs/0806.3743

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