You should now be looking at four edges all oriented correctly.įor the “Dot” case shown in the first picture, just do either of these algorithms to get a different case. Make sure that the yellow bar (the two edges and the middle sticker) is horizontal, then do: The third image shows the “Line” shape, where the two yellow pieces showing are opposite one another. If done correctly, you should now be looking at the yellow cross. Do the required number of U or U' moves to get this L as shown in the picture: the corner that the two edges trap needs to be in the top left. When you have an “L” shape, where the two yellow pieces showing are adjacent one another. If you are in a hurry you can speed up the process by doing two jumps at once with this: To transform the Magic Cube from one state to the other, you have to apply the following short algorithm, watching out for the L shape and the line to be positioned as required:
If the edges are solved in a plus shape like the cross we made at the start (the last image), you can skip this stage.īeside the solved cross you can also have a “Dot”, an “L” shape or a “Line” as pictured above. Use the color picker, apply an algorithm or use a random scramble. Set up the scramble pattern, press the Solve button and follow the instructions. These are the four possible edge positions that you can have:ĭo this to transfrom to the next state: F R U R' U' F' Calculate the solution for a scrambled cube puzzle in only 20 steps. The guide is broken into five parts, with a. Either none, all, or two of the edges will already be oriented correctly (the yellow part is facing up). This infographic, shared by Reddit user CitizenYellow, lays out the trick to solving a Rubiks Cube step-by-step. The next will move these pieces around and thus solve the cube. In this step will orient all of the pieces so that the yellow face is facing up for all of them. We're going to solve the top layer edges in two steps. 2/3 of the puzzle is solved, and every piece left to be solved has yellow on it somewhere.
Step one, then, is to move the cube into one of those configurations, and step two is to use the short solution for that partially solved configuration.We're nearly there now. How to Solve a Rubiks Cube Solving the First Cross Solving the Bottom Corners Solving the Middle Layers Solving the Top Cross Solving the Top, Middle. The strategy was based on earlier work developed by mathematician Herbert Kociemba that broke solving a cube into two steps, based on a special set of about 19.5 billion partially-solved configurations that are known to have relatively short solutions. Rubiks cube and prove (using group theory) that our methods always enable us to solve the cube. An early mathematical analyst of the cube, Morwen Thistlethwaite, was able to prove that any cube could be solved in at most 52 moves.Ĭomputer programmer Tomas Rokicki came up with a strategy for finding relatively short solutions for Rubik's Cube configurations. We will both develop methods for solving the. Over the decades, various upper bounds were proven. The remaining question, then, is whether or not there are any cubes that need more than 20 steps to solve. That sets a lower limit on what God's Number could be. Earlier this year, while putting together a video about the world’s fastest solvers of the Rubik’s Cube, I decided to devote some time to learning to solve the classic puzzle myself. In 1995, mathematician Michael Reid found a Rubik's Cube configuration called a "superflip" and proved that it required at least 20 moves to solve. The key to answering a question like finding the smallest number of moves to solve any configuration is to take advantage of the relationships between different configurations. Going through and trying to find the shortest solution for every single one of those configurations, then, is essentially impossible. An analysis of all the possible permutations of where the smaller constituent cubes (often called "cubies") can end up shows that there are about 43 quintillion - 43,000,000,000,000,000,000 - possible configurations of the Rubik's Cube. One reason it took so long to answer such an apparently straightforward question is the surprising complexity of the Rubik's Cube. In 2010, a group of mathematicians and computer programmers proved that any Rubik's Cube can be solved in, at most, 20 moves. One immediate and obvious question, dating back to the original invention of the cube, is, given a particular configuration of a cube, what's the smallest number of moves needed to solve the puzzle? Relatedly, what is the smallest number of moves needed to solve any configuration of the Rubik's Cube, a number that cube aficionados refer to as "God's number?"Īs Erno Rubik put it in a recent interview with Business Insider, this question is "connected with the mathematical problems of the cube."Īmazingly, it took 36 years after the invention of the toy to come up with an answer.