On the cop number and the weak Meyniel's conjecture for algebraic graphs

Abstract

In this article, we study the game of cops and robbers in algebraic graphs. We show that the cop number of the Cayley sum graph of a finite group G with respect to a subset S is at most its degree when the graph is connected, undirected. We also show that a similar bound holds for the cop number of generalised Cayley graphs and the twisted Cayley sum graphs under some conditions. These extend a result of Frankl to such graphs. Using the above bounds and a result of Bollobás-Janson-Riordan, we show that the weak Meyniel's conjecture holds for these algebraic graphs.