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arXiv · 1611.07858

Leavitt path algebras with bounded index of nilpotence and simple modules over them

Kulumani M. Rangaswamy·Ashish K. Srivastava
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Abstract

In this paper we completely describe graphically Leavitt path algebras with bounded index of nilpotence and show that each graded simple module $S$ over a Leavitt path algebra with bounded index of nilpotence is graded $\Sigma$-injective, that is, $S^{(\alpha)}$ is graded injective for any cardinal $\alpha$. Furthermore, we characterize Leavitt path algebras over which each simple module is $\Sigma$-injective. We have shown that each simple module over a Leavitt path algebra $L_K(E)$ is $\Sigma$-injective if and only if the graph $E$ contains no cycles, and there is a positive integer $d$ such that the length of any path in $E$ is less than or equal to $d$ and the number of distinct paths ending at any vertex $v$ (including $v$) is less than or equal to $d$.

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Kulumani M. Rangaswamy, Ashish K. Srivastava. 2016-11-23. Leavitt path algebras with bounded index of nilpotence and simple modules over them. https://arxiv.org/abs/1611.07858

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