Cracking the Rubik’s Cube in 26 moves… or fewer
You might think this is a joke, but Dan Kunkle and Gene Cooperman of Northeastern University, Boston beg to differ. They can do theirs in no more that 26 moves !! Kunkle, a computer scientist at NEU and his advisor Cooperman jointly came up with some advanced mathematical and computational strategies that helped them solve this mind-boggling puzzle in no time.
The Rubik’s cube can have 43 quintillion (43 million billion) configurations, which makes it way beyond the scope of any supercomputer to find the quickest way to unscramble a given a random starting arrangement in the shortest possible time. In a paper titled Twenty-Six Moves Suffice for Rubik’s Cube, they’ve outlined the exact process they followed to achieve this feat – which has beat the previously demonstrated record of 27 moves (Silviu Radu of the Lund Institute of Technology, Sweden).
Algorithms that were the byproducts of this research can prove to be of profound help in solving problems as disparate as scheduling air flights and determining how proteins will fold. Even with these advanced algorithms in place, it took their supercomputer a stint of 63 hours to arrive at a conclusion which solved the cube in 29 moves. But not to be deterred at that, they further fine-tuned their routines and finally succeeded in eliminating 3 more steps.
Their findings were presented at the International Symposium on Symbolic and Algebraic Computation in Waterloo, Ontario on the 29th of July, 2007.
Found via: Cracking the Cube (MathTrek).