Alex's Adventures in Numberland - Alex Bellos [102]
The original Rubik’s Cube is a 3 × 3 × 3 array made up of 26 smaller cubes, or cubies. Each horizontal and vertical ‘slice’ can be rotated independently. Once the pattern of the cubies is jumbled, the aim of the puzzle is to twist the slices so that each side of the cube has cubies of just one colour. There are six colours, one for each side. Moscovich told me Ernö Rubik was doubly brilliant. Not only was the idea of the cube a stroke of genius, but the way he made the blocks fit together was an outstandingly clever piece of engineering. When you dismantle a Rubik’s Cube there is no separate mechanical device holding it all together – each cubie contains a piece of a central, interlocking sphere.
As an object, the cube itself is sexy. It is a Platonic solid, a shape that has had iconic, mystical status since at least the ancient Greeks. The brand name was also a dream: catchy, with delicious assonance and consonance. The Rubik’s Cube had an Eastern exoticism too, not from Asia this time but from Cold War Eastern Europe. It sounded a lot like Sputnik, the original showpiece of Soviet space technology.
Another ingredient in its success was the fact that while solving the cube was not easy, the challenge did not put people off. Graham Parker, a builder from Hampshire, kept at it for 26 years until he achieved his dream. ‘I have missed important events to stay in and solve it and I would lay awake at night thinking about it,’ he said, after an estimated 27,400 hours of cube time. ‘When I clicked that last bit into place and each face was a solid colour I wept. I cannot tell you what a relief it was.’ Those who solved it over a more manageable period invariably wanted to solve it again, but quicker. Reducing one’s Rubik’s record became a competitive sport.
Speedcubing has only really taken off, however, since around 2000. One of the reasons is thanks to a sport even more quirky than the timed solving of mechanical puzzles. Speedstacking is the practice of stacking plastic cups in set patterns as fast as you can. It is both mesmerizing and awesome – the top stackers move so fast it is as if they are painting the air with plastic. The sport was invented in California in the 1980s as a way of improving children’s hand-eye coordination and general fitness. It is claimed that 20,000 schools worldwide now include it in their physical education curriculum. Speedstacking uses specialized mats that have a touch sensor linked to a stopwatch. The mats provided the speedcubing community for the first time with a standardized method to measure the time it takes to solve the cube, and are now used in all competitions.
Every week or so, somewhere around the world now hosts an official speedcubing tournament. To make sure that the starting position is sufficiently difficult in these competitions, the regulations stipulate that cubes must be scrambled by a random sequence of moves generated by a computer program. The current record of 7.08 seconds was set in 2008 by Erik Akkersdijk, a 19-year-old Dutch student. Akkersdijk also holds the record for the 2 × 2 × 2 cube (0.96secs), the 4 × 4 × 4 cube (40.05secs) and the 5 × 5 × 5 cube (1min 16.21 secs). He can also solve the Rubik’s Cube with his feet – his time of 51.36secs is fourth-best in the world. However, Akkersdijk really must improve his performance at solving the cube one-handed (33rd in the world) and blindfolded (43rd). The rules for blindfolded solving are as follows: the timer starts when the cube is shown to the competitor. He must then study it, and put on a blindfold. When he thinks it is solved he tells the judge to stop the stopwatch. The current record of 48.05secs was set by Ville Seppänen of Finland in 2008. Other speedcubing disciplines include solving the Rubik’s Cube on a rollercoaster, under water, with chopsticks, while