Solving Rubik's Cube

Thecla

Can solving Rubik's Cube be learned?
I see people solving the cube in under 30 seconds.You think these people have some inborn talent in spatial rotation recognition that only geniuses possess.
If someone were to give me a cube that had to be solved in 24 hours to receive a million dollar prize, I don't think I could do it.
With so many different starting positions it seems like it can't be taught to the average person.
You either have the ability or you don't.

SteveL27

Long time ago SciAm ran a piece about the application of group theory to Rubik's cube. They profiled some "cubemeisters" who used special well-oiled competition cubes to solve the puzzle very fast. Don't know if the article's online or not. Didn't find it in a very cursory search, but you can probably do better.

I did find an academic paper on group theory & RC.

http://www.math.harvard.edu/~jjchen/...9;s%20Cube.pdf

(edit) Still couldn't find the original SciAm article, but if you check out the references on Wiki you'll find something. Bottom line, there are definitely theory-based algorithms to solve the cube. What people do is learn an algorithm then practice like crazy so they can operate quickly.

http://en.wikipedia.org/wiki/Rubik's_Cube

Thecla

I see 7 and 8 year old kids solving the Cube on You Tube. I am sure they know nothing of Group Theory.Who taught these kids? How did they learn?
I also remember the Sci. Am. article in the early 1980s when the Cube was first popular.

Mark M

How about this? This video has 22 million views:

http://www.youtube.com/watch?v=HsQIoPyfQzM

Jimmy Snyder

Solution.

QuarkCharmer

These people just memorize an algorithm and develop muscle memory. To me, it's about as impressive as some child listing pi to the 500'th decimal. Sure, that neat, but not useful at all, and certainly no indication of intelligence.

TheStatutoryApe

Its basically a rote memorization formula. You can find a solution formula in the booklet that comes with most rubiks cubes now a days. Its basic and easy. I got to the point where I could solve a cube in about two to three minutes, and that was using the long solution. There are apparently quicker solution methods. And I am certainly nothing near a genius.

M Quack

It is quite easy. Unless you want to break speed records, you have to memorize something like 4-5 sequences of 10-15 rotations each. You solve the cube by layers, first one face and the "rim" around it, then the middle band, and then the opposite layer with its rim. There are plenty of instructions on how to do that on the web.

The masters memorize about 100 sequences and choose the most efficient ones depending on the configuration of the cube.

The alternative is to use a heap of Lego pieces and your phone.

http://www.youtube.com/watch?v=_d0LfkIut2M

Jonathan Scott

One can find little books or information on the internet which gives systematic rules for shuffling around two or three cubes without affecting others. These rules tend to involve several steps because of the need to undo side-effects on the other positions. When my kids (who were 14 and 10 at the time) found my old booklet on how to solve it, they memorised most of the steps within a day or so and can normally do the cube in two or three minutes.

Experts use moves with fewer steps which take the side-effects into account but have a more complex effect. Again, they just learn to see the patterns and memorise the moves.

Of course, the process of working out the moves in the first place is much more complicated. The basic principle is that simple moves have big side-effects, so moves that have a simple effect tend to involve several steps, typically preparing the required change, then performing it, then undoing the side-effects by reversing the preparation moves.

leroyjenkens

I'm going on 29 years of never having solved a Rubik's Cube. I've also never done a backflip. Both, of course, can be learned. If they couldn't, no one could do it.

I like Serena

I knew a guy who could solve it in 13 seconds.
He was practicing and asked everyone to help him practice.

I took a cube out and reversed it.
After 5 seconds he found out and looked stupidly at me for about 5 seconds, since he couldn't believe I had done that.
Then he popped a cube out, reversed it, and finished solving the cube.
It still took him less than 20 seconds!

To put things into perspective, he was studying computer science, but had to stop after a couple of years, since he couldn't complete the courses.

JJacquelin

A mnemonic method (for French people):
"Méthode mnémotechnique de résolution du Rubick's cube"
http://www.scribd.com/people/documen...575-jjacquelin

Thecla

It must be like a complicated game of tic tac toe. When you were a little kid you got all excited, playing many games. A little older, you found out the winning strategy and you lost interest in tic tac toe.
With rhe Cube there are some algorithms to learn. The question becomes not how to solve it, but how fast can you solve it. Like a previous poster said, for record times a lot of muscle memory is involved.

Danger

I'm with Jimmy, although my approach would involve explosives rather than a hammer.
I bought a book about how to solve one. Using that book, it still takes me over 5 minutes. One guy in particular, who was in the same SF club with me 30 years ago, could whip up any kind of checkerboard or striped design within a minute. When they came out with "Rubic's Revenge", it took him a very short while to be able to solve it within a minute. It took him a bit longer to make patterns.

M Quack

This is quite amusing

http://web.mit.edu/sp.268/www/rubik.pdf

I_noscopedJFK

I was really fascinated when Will Smith solved it in The Pursuit of Happiness, but after I saw a video on youtube explaining how to do it, and solving it myself in 3 minutes, I realized it has nothing to do with intelligence - just memorizing some algorithms

Alshia

The answer is, it depends on how you solve it. If you solve it with algorithms, virtually anyone can do it. It's just a series of instructions. Without algorithms, yes, intelligence is required.

But keep in mind that algorithms are like general formulas; they are derived to make things more convenient. Thus, if you solve algorithms, BUT you made them yourself, that is also an indicator of intelligence.

I can only solve two layers effortlessly without using algorithms. For the third layer, I will need to apply commutators and conjugators, which will require quite a bit of thought.