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arXiv · 1208.1897

Intersection Graph of a Module

Ergün Yaraneri
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Abstract

Let $V$ be a left $R$-module where $R$ is a (not necessarily commutative) ring with unit. The intersection graph $\cG(V)$ of proper $R$-submodules of $V$ is an undirected graph without loops and multiple edges defined as follows: the vertex set is the set of all proper $R$-submodules of $V,$ and there is an edge between two distinct vertices $U$ and $W$ if and only if $U\cap W\neq 0.$ We study these graphs to relate the combinatorial properties of $\cG(V)$ to the algebraic properties of the $R$-module $V.$ We study connectedness, domination, finiteness, coloring, and planarity for $\cG (V).$ For instance, we find the domination number of $\cG (V).$ We also find the chromatic number of $\cG(V)$ in some cases. Furthermore, we study cycles in $\cG(V),$ and complete subgraphs in $\cG (V)$ determining the structure of $V$ for which $\cG(V)$ is planar.

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Ergün Yaraneri. 2012-09-09. Intersection Graph of a Module. https://doi.org/10.1142/s0219498812502180

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