On the chromatic number of the Erdős-Rényi orthogonal polarity graph

Xing Peng, Mike Tait, Craig Timmons

For a prime power $q$, let $E{R}_q$ denote the Erdős-Rényi orthogonal polarity graph. We prove that if $q$ is an even power of an odd prime, then $χ( ER_{q}) \leq 2 \sqrt{q} + O ( \s…