Rubik’s Cube & Every Way It Can Be Solved
WASHINGTON. An international team of researchers using computer power from Google has found every way the popular Rubik’s cube puzzle can be solved, showing it can always be completed in 20 moves or less.
The research ends a 30-year search for the most efficient way to correctly align the 26 coloured cubes that make up Erno Rubik’s invention.
”It took 15 years after the introduction of the cube to find the first position that provably requires 20 moves to solve,” the team said. ”It is appropriate that 15 years after that, we prove that 20 moves suffice for all positions.” Using computers lent to them by Google, the team crunched through billions of cube positions, solving each one over a period of ”just a few weeks”.
The study builds on the work of a pantheon of Rubik’s cube researchers, starting with Morwen Thistlethwaite, who in 1981 showed 52 moves were sufficient to reach the solution from any given cube position.
By May 1992, Michael Reid showed 39 moves was always sufficient, only to be undercut a mere day later by Dik Winter, who showed 37 moves would work.