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Rubik's Cube Record Broken

Posted by simoniker on from the rubik's-kubrick-rubrick dept.

martinX writes "The Courier Mail has a story about a San Fran software developer who spins the cube faster than anyone else on the planet: 20 seconds to solve Rubik's Cube. I didn't think anyone still played with them." The winner, Dan Knights, said "It's sort of a dream come true", and credited Jessica Fridrich's cube-solving method as the key to winning, leaving the originator of the method in second place at the World Rubik's Cube Championships in Toronto at the weekend.

7 of 41 comments (clear)

  1. Video? by akudoi · · Score: 1, Interesting

    Anyone know if theres a video of him actually solving the cube? Or anyone solving one. It would be interesting to watch.

  2. Obligitory Lego URL by Kris_J · · Score: 3, Interesting

    http://jpbrown.i8.com/cubesolver.html

  3. Solve times by Kethinov · · Score: 4, Interesting

    I know a guy who can solve them in under 3 minutes. He memorized all the algorithms and so on. Fascinating concept. I never knew they were actually solvable until I met him. A lot of people joke that "oh gimme a screwdriver and I'll solve it" but when you break it down step by step, they actually do have a simple set of steps that can be taken to solve them, like any other logic problem. Although he did tell me that they can be taken apart and rearranged in such a way that they CAN be made unsolvable. He told me "never try to solve a cube until you've seen it solved. You never know what kinds of assholes will stack the deck on you to make you look stupid."

    --
    You're right, I wouldn't steal a car. But if it were possible, I sure as hell would download one!
    1. Re:Solve times by mcmonkey · · Score: 2, Interesting

      Sub-3 minute times aren't too hard with a little practice. I have "The Simple Solution to Rubik's Cube" (not my auction, just the first link to the book I found).

      As you can see from the picture, it's barely a book--more of a pamphlet. There aren't more than a couple dozen algorithms in the whole thing, and I don't think more than 8 or 10 possible positions you have to look for at any one stage.

      The plan here is to get you solving the puzzle by minimizing the number of cubes you're positioning at once and so minimizing the number of possible combinations to memorize.

      I've topped out at a little under 2 minutes, and I'd bet even with a good, well-oiled cube this method tops out at over a minute. The short-comings of this method really show when you get to the last 4 cubes to place. There's basically one configuration that leads to the solution. And you repeat a short series of moves until the last four cubes are in that configuration.

      It wastes time, but you only need to memorize 1 configuration--the solvable one--and 2 series of moves--1 to solve and 1 to rearrange.

      I thought sub-minute times were world-class, but I had no idea how much had been done sub-30 seconds. I think a question better than vi or emacs is top-down or bottom-up.

  4. initial state of cube? by croddy · · Score: 2, Interesting

    how is it possible to have a rubik's cube competition? is there a standardized initial state for the cube?

    1. Re:initial state of cube? by Vryl · · Score: 2, Interesting

      I am pretty sure that there is a proof that any configuration of a cube is at most 21 moves away from any other. That is also to say that you can solve any position in 21 moves or less. It is known, I believe, as 'Gods Algorithm'.

      So, 25 random moves is at least 4 that are redundant, ie, don't add to the complexity of the puzzle.

  5. I am forshamed by wizarddc · · Score: 2, Interesting

    I can do the cube, and have been able to since like 8th grade. When I first solved it, it would take me like a half hour. Then in 10th grade, I found a solution online that allowed me to do it in 10 minutes. And then my senior year, I found a 3 minute solution. After a few more years of using that method, I can regularly get a cube solved in a minute and a half. I know there are quicker algorithms out there, but I have dedicated the time for them. Most people have the patience and intrigue to stick around for a couple of minutes while I solve it. They always say "You can do that so fast!". I'ts like someone telling you your Ford Taurus is fast when they've never seen a Corvette. I'm always like "I don't do this fast, trust me". I always thought the record was less than 20 seconds. I remember seeing a guy do it in 16 seconds before. Maybe this is the average of a few cubes, I guess.

    --
    Th