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arXiv · 1507.05984

On graded irreducible representations of Leavitt path algebras

Roozbeh Hazrat·Kulumani M. Rangaswamy
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Abstract

Using the E-algebraic systems, various graded irreducible representations of a Leavitt path algebra L of a graph E over a field K are constructed. The concept of a Laurent vertex is introduced and it is shown that the minimal graded left ideals of L are generated by Laurent vertices and/or line points leading to a detailed description of the graded socle of L. Following this, a complete characterization is obtained of the Leavitt path algebras over which every graded irreducible representation is finitely presented. A useful result is that the irreducible representation V_[p] induced by infinite path tail-equivalent to an infinite path p is graded if and only if p is an irrational infinite path. We also show that every one-sided ideal of L is graded if and only if the graph E contains no cycles. Supplementing a theorem of one of the co-authors that every Leavitt path algebra is graded von Neumann regular, we describe the graded self-injective Leavitt path algebras. These turn out to be direct sums of matrix rings of arbitrary size over K and k[x,x^-1].

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Roozbeh Hazrat, Kulumani M. Rangaswamy. 2015-07-21. On graded irreducible representations of Leavitt path algebras. https://arxiv.org/abs/1507.05984

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