Amateur mathematician partially solves 60-year-old problem

The 1581-vertex, non-4-colourable unit-distance graph G. Credit: arXiv:1804.02385 [math.CO] Professional biologist and amateur mathematician Aubrey de Grey has partially solved the Hadwiger-Nelson problem, which has vexed mathematicians since 1950. He has published a paper describing the solution on the arXiv preprint server. The Hadwiger-Nelson problem came about when Edward Nelson and Hugo Hadwiger wondered about…