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Rubik's Cube Proof Cut To 25 Moves
KentuckyFC writes "A scrambled Rubik's cube can be solved in just 25 moves, regardless of the starting configuration. Tomas Rokicki, a Stanford-trained mathematician, has proven the new limit (down from 26 which was proved last year) using a neat piece of computer science. Rather than study individual moves, he's used the symmetry of the cube to study its transformations in sets. This allows him to separate the 'cube space' into 2 billion sets each containing 20 billion elements. He then shows that a large number of these sets are essentially equivalent to other sets and so can be ignored. Even then, to crunch through the remaining sets, he needed a workstation with 8GB of memory and around 1500 hours of time on a Q6600 CPU running at 1.6GHz. Next up, 24 moves."
What are these magic 25 moves that can solve a rubik's cube regardless of starting position?
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The correct answer is a hammer.
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Imagine a Beowulf cluster of those!
When I was little, I still remember annoying the crap out of my older brother by "solving" his Rubik's cube removing and replacing the stickers in the correct location. Eventually the glue would wear off the dots and you would suddenly have a slightly easier puzzle to solve.
This Green Technology uses 1/26th less energy to solve a rubix cube! When's the IPO?
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I consider a Rubik's Cube to be "solved" regardless of its starting position. I subscribe to the Fred Rogers solution: it's fine just the way it is.
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Well, that explains it; considering how fast the technology is changing, they probably didn't have 2.4 GHz versions 62 days ago.
No, just make the rubix cube out of the oled keys of the optimus keyboard. Integrate with bluetooth and "solve" the rubix in a single button press.
Well.. maybe. Or Maybe not. But Definitely not sort of.
I painted all 6 sides the same colour on mine.
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In my research, I've reduced female behavior to a set of 50 million parameters. By partitioning this space into subspaces and finding equivalent sets, I think I might be able to get laid.
However I've noticed a problem: if I introduce a parameter to model a female's response to this research, the spaces collapse to zero, i.e., a null set.
I find this quite puzzling. Simply by examining my chances of getting laid, I reduce my chances to zero.
Did I mention I can solve the Rubik's cube in 25 moves?
I've been doing some interesting work in the other direction. I've managed not to solve a Rubik's cube in what I estimate to be 1.5 million moves. That seems to be the upper limit after which the stickers fall off.
I started with a solved cube and now it looks totally scrambled.
....or a girlfriend.
The sound of the CPU cooling fan at 2.4GHz?
and around 1500 hours of time
pfffft... Java
A cooling fan at 2.4 billion revolutions a second would probably sound more like atoms tearing apart. :)
He or she did suggest 25 moves, no more, no less. I counted them myself so that you don't have to.
If the fan has a diameter exceeding 3 1/8 inches, it would be the sound of fan blades of infinite mass traveling backwards in time.
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Moving colored stickers? Amateurs! I can solve any cube in three moves... with a can of spray paint. Point, spray, spin.
When our name is on the back of your car, we're behind you all the way!
I one met Erno Rubik himself.
Nice guy and all, but it took me half an hour to finish shaking his hand.
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Or perhaps Rubik's@home.
You want fun, go home and buy a monkey!
Hello. I do not have Asperger Syndrome and therefore could not understand what was just written in the synopsis. Worst yet, I do not even understand why it is important that a person can solve a Rubiks cube in 25 moves. I feel really left out and as a result I am starting a Persons without Asperger Support Group. If you too are totally lost by this article and fell left out, please join.
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