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arXiv · 1905.08391

Group gradings on finite dimensional incidence algebras

Ednei A. Santulo Jr.·Jonathan P. Souza·Felipe Y. Yasumura
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Abstract

In this work, we classify the group gradings on finite-dimensional incidence algebras over a field, where the field has characteristic zero, or the characteristic is greater than the dimension of the algebra, or the grading group is abelian. Moreover, we investigate the structure of $G$-graded $(D_1,D_2)$-bimodules, where $G$ is an abelian group, and $D_1$ and $D_2$ are the group algebra of finite subgroups of $G$. As a consequence, we can provide a more profound structure result concerning the group gradings on the incidence algebras, and we can classify their isomorphism classes of group gradings.

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Ednei A. Santulo Jr., Jonathan P. Souza, Felipe Y. Yasumura. 2019-05-21. Group gradings on finite dimensional incidence algebras. https://doi.org/10.1016/j.jalgebra.2019.10.026

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