The Rubik’s Cube turns 50

BRIGHT and early on the first Saturday in January, Tomas Rokicki and a few hundred fellow enthusiasts gathered in a vast lecture hall at the Moscone Center in downtown San Francisco. A big math conference was underway and Rokicki, a retired programmer based in Palo Alto, California, had helped organise a two-day special session about “serious recreational mathematics” celebrating the 50th anniversary of the Rubik’s Cube. Erno Rubik, the Cube’s inventor, was top of the show at 8 am, via video conference from the south of Spain.