Power Graphs of Finite Groups

Abstract

The power graph $\mathcal{P}(G)$ of a group $G$ is the graph whose vertex set is $G$, having an edge between two distinct vertices if one is the power of the other. The directed power graph $\vec{\mathcal{P}}(G)$ of a group $G$ is the digraph whose vertex set is $G$, having an arc from $x$ to $y$, with $x\ne y$, whenever $y$ is a power of $x$. We rewrite two Cameron's articles concerning the reconstruction of $\vec{\mathcal{P}}(G)$ from $\mathcal{P}(G)$. We correct mistakes that appear in the papers. In particular, we add missing cases needed to complete the main theorems of these articles. We also study the quotient of the power graph under some equivalence relations. We close the thesis with lower bounds for the maximum length of a cycle in the power graph of a group.