Eli5: How do rubiks cubes work and how do some solve them so quickly while others can’t?

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Anonymous 0 Comments

I’m not sure what you mean by how do they work so I’ll address it by explaining at least one common misconception. The puzzle is constructed with 6 stationary centers and then 20 pieces that have multiple stickers on each. These pieces are solid plastic meaning that the relationship of stickers doesn’t change. There will always be a red white blue corner with a particular order, there will always be a green white edge piece, etc. Once you understand that, watching the colors move around is less intimidating as you start thinking them as individual pieces to manipulate.

Now as for how people speed solve, it’s about pattern recognition and sequence memorization and muscle memory. The core concept is that you recognize that one or more pieces are in one place and they need to move to their solved locations. Then you recall the sequence of moves that executes that swap and rely on muscle memory to do it quickly and not process each individual move. Its “common knowledge” that Rubik’s cubes can be put into a random scrambled state and there will always be a sequence of under 20 moves that solves them. But I promise, no cuber uses this fact in any sense. There is an unfathomable number of scrambles and sequences you’d need to memorize which is impossible. Instead, cubers tend to memorize algorithm sets in the few hundreds and use them in series to solve layer by layer. In addition, you are granted inspection time at the beginning of a solve in competition. You can preplan your first several moves and execute them without thinking while trying to look ahead and find your next pieces

Anonymous 0 Comments

The Rubik’s cube is just a bunch of interlocking cube faces attached to a central shape by a pivot. This lets all of the faces rotate around that center axis, meaning that all of the corners and edges can be moved around, while the center squares of each face stay in their positions. They’re pretty easy to take apart and they make a lot of sense once you’ve seen the inside mechanism.

As for solving them, it’s just something you learn. Most people follow a series of repeatable steps called an “algorithm” that can get you to a solved state from any position. For example, I learned to start with the white side, make a white cross, then get the white corners into place, then flipping it over, solving the yellow side (cross first, then corners) and getting the corners in the right places last.

If you want to solve them faster and faster, you learn more complicated algorithms that can solve it quicker – these take much more memorization and experience to do. People with lots of experience can quickly look at a cube, figure out the fastest method to get to a familiar position, and then use their memorized algorithm to finish the solve.

Anonymous 0 Comments

I’m not sure what you mean by “how do Rubik’s cubes work”. 

Solving a Rubik’s completely on your own is really hard. Most people who can solve one have learned a series of moves. The ways those work is you solve it section by section. So you might do one side or one corner and then build up. If there’s a piece that you need to move somewhere else, then there’s a series of steps you can memorize and follow that will move that one piece without moving the stuff you already solved. 

If someone learns the most basic method of solving a Rubik’s cube, they’ll be able to solve it in about 5 minutes. If you’re at a competition, and you’re solving the cube in seconds, then you’re using a different method. If you’re solving it in 5 minutes, you might have to do the same move 3 times to solve one section of the cube. At a competition level, you’ll have memorized a lot more specific moves so that you can move all of those at once. There’s a lot else you’re practicing if you’re solving a Rubik’s cube that fast, but that’s the rough idea. 

Anonymous 0 Comments

When the Rubik’s cube first came out, much was made of the fact that there were 43 quintillion possible combinations, when what really mattered was that there were 20 pieces that had to be moved into their proper places. The people who solved it basically figured out how to move those 20 pieces into their proper places one (or more) at a time. There would be a series of turns that would move _this piece_ to _that spot_ without disturbing the placement of pieces that were already correct. Over time, people developed more efficient patterns that could move multiple pieces into the right places simultaneously, but the underlying idea was the same — all the permutations didn’t matter; in the end you just had to get 20 pieces into the right places.

That’s not to say that coming up with these moves was EASY. When the cube first came out, the typical person didn’t have access to much in the way of computing power. People worked it out in their head. People who were mechanically inclined and had a gift for spatial relationships could “see” how to get this piece to that spot. The rest of us bought a book at B. Dalton and memorized the moves in it. [Here’s the one I used.](https://www.amazon.com/Jeff-conquers-cube-45-seconds/dp/0812870972)

Anonymous 0 Comments

The individual pieces of a Rubik’s Cube are called “cubies”. The center cubie on each face is in a fixed position relative to the other faces: red is opposite orange, blue is opposite green, and white is opposite yellow. These cubies are all attached to a central cross piece that allows only allows them to rotate, but not change position.

Now, all the cubies have a piece on the interior, not visible when the cube is assembled, that forms a piece of a ring. These pieces interlock with each other in such a way that the individual cubies can slide past each other while also keeping them from falling off the cube.

Anonymous 0 Comments

If you really want to understand, buy a cube and learn to solve it.

I like this tutorial: [https://ruwix.com/the-rubiks-cube/how-to-solve-the-rubiks-cube-beginners-method/](https://ruwix.com/the-rubiks-cube/how-to-solve-the-rubiks-cube-beginners-method/)

Once you memorize that method, look into the faster methods. You will start to see why most people can learn to do it the slow way, but far fewer will learn a fast method.