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Structures and Representations of Generalized Path Algebras

Shouchuan Zhang·Yao-Zhong Zhang
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Abstract

It is shown that an algebra $\Lambda $ can be lifted with nilpotent Jacobson radical $r = r(\Lambda)$ and has a generalized matrix unit $\{e_{ii}\}_I$ with each $\bar e_{ii} $ in the center of $\bar \Lambda = \Lambda /r$ iff $\Lambda $ is isomorphic to a generalized path algebra with weak relations. Representations of the generalized path algebras are given. As a corollary, $\Lambda $ is a finite algebra with non-zero unity element over perfect field $k$ (e.g. a field with characteristic zero or a finite field) iff $\Lambda $ is isomorphic to a generalized path algebra $k (D, \Omega, \rho)$ of finite directed graph with weak relations and $dim {\} \Omega < \infty $; $\Lambda $ is a generalized elementary algebra which can be lifted with nilpotent Jacobson radical and has a complete set of pairwise orthogonal idempotents iff $\Lambda $ is isomorphic to a path algebra with relations.

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Shouchuan Zhang, Yao-Zhong Zhang. 2004-02-12. Structures and Representations of Generalized Path Algebras. https://arxiv.org/abs/math/0402188

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