# Why It's Almost Impossible to Solve a Rubik's Cube in Under 3 Seconds | WIRED

Jun 02, 2021
Most people are familiar with the Rubik's Cube, but very few have

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d it and that is because if you don't know the moves, the Rubik's Cube is one of the most difficult puzzles ever created. Frankly, three by three by three is too. hard, okay, now it really is, a lot of that has to do with the fact that there are literally billions upon billions of ways to code this, but what's equally incredible is that with a few weeks of practice With dedication and a little memorization, most people can learn to

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any of those problems in a few minutes, but there are some people who can solve it even faster, much faster.
They are called speed

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rs and the best of them can shape a Rubik's

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in less than ten

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. If that wasn't impressive enough, the fastest solution ever recorded in a competition is a ridiculous three point four seven

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look at that time, today we're going to see him solving a Rubik's cube in under three seconds, it's

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to find. find out what it takes talked to a world record holder got a crash course in technique from some local speed cubers now the problem here is that you notice things here on the edge don't match up the problem here is that I don't even see that that's it a problem here and I talked about the mind-blowing mathematics behind the cube with a computer scientist.

## why it s almost impossible to solve a rubik s cube in under 3 seconds wired...

There are more positions in Rubik's Cubes and there are grains of sand in every feature of the Earth. The Rubik's Cube was invented by Hungarian architect Erno Rubik in 1974. Actually, it started as an experiment. Rubick wanted to know if it was possible to design a cube made of smaller blocks that could move independently without falling apart. Only later did he realize that he had also created a puzzle and that puzzle became very popular. It wasn't long before people competed to see who could solve it the fastest at the first Rubik's Cube World Championship in 1982. It took competitors up to a minute to solve the cube, but speed solvers, like the holder of the world record Felix MPEG, have been undermining those problems. times since then, I think

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100 competitions around the world broke many world records and won many grudges.
A competition round consists of five resolution attempts. A computer randomly generates the combinations to make sure they are difficult enough for each competitor. solve the same five problems that ask you are you ready? I'll take the lid off and then you have the option of 15 seconds to look at the cube and start the timer so you have that time to look at it and then you have to place your hands. press the stopwatch and then fill the cube and then return your hands to like the stack, that stopwatch now is probably a good place to mention that unconditional cube roots actually care more about average times than simple solutions.
The fact is, sometimes you just get lucky. A better test of speed cubers' skill is to have them solve five cubes and average the three times in between. zem DAG currently holds the average resolution record of five point six nine seconds, but single resolution times still matter and xem Dex used to hold that record too. with a time of four point two two seconds, until Chinese speed cuber You Sheng demolished it last fall with a time of three point four seven seconds, so how unexpected was it for someone to come along and break his single resolution record in as 3! /4 of a second which was pretty unexpected to be honest, like in speed cubing you don't usually see those kind of crazy jumps in time, you can still get a really incredibly fast solution with just one attention if you have an easy fight and a big block and it just so happened that you know there are so many people going to so many competitions all the time that something like this was probably going to happen, but we really didn't expect it to be so soon, so let's leave the speed cubing aside. a second because many people, including myself, have never solved the Rubik's Cube in any amount and that's because actually solving one from scratch without anyone's help without watching any tutorial videos online is really very difficult, honestly It's just that if you see someone solving a Rubik's cube, they are almost certainly using a memorized sequence of moves to do it.
This is Tyson Mao, he is a co-founder of the World Cube Association and I asked him to teach me the basics. I would say there are probably three things to think about in terms of what makes someone solve the cube quickly. The first is the method. There are many methods for solving a cube, but they are all based on something cubers call algorithms. They memorize sequences of moves that players use to solve the cube section. section by section now as a general rule, the more algorithms you know, the fewer moves you will need to solve the cube.
A beginner who has memorized less than 10 algorithms could solve a cube and say 120 moves, while an expert who has memorized hundreds of algorithms can solve the cube and say about 50 or 60 moves and, as expected, fewer moves can be translated. at faster resolutions. The second thing that contributes is that Allah teaches all the cubes how fast you can spin the cube. The world's fastest speed cubes averaged around 10 turns per second over the course of a full song and much more than that in abbreviated versions. Take this final sequence of 16 movements for example, it looks like this 1 2 3 4 with this ring finger 5 6 7 8 and now you have to push back with this ring finger 9 10 11 12 pull 13 14 15 16 push up the People can execute those 16 movements in less than a second.
Are you serious? That is surprising. The third thing that contributes to the time it takes. to solve the cube is the time it takes you to process the information. It doesn't help you if it takes you five seconds to figure out what the next step is. Your goal is to try to look ahead and see what the moves are for the next step. are while you do the actual one and reduce a pause between those steps and then there is the hardware itself, as you can see there are many different types of 3x3 cubes from the old school version which was clunky, rigid and difficult to use.
Sleek new models that rotate easily and include small magnets to help the faces snap into position. The hardware itself is involved to the point where now it's like it's really good. If you give me a cube from five years ago, it's probably taking off. like a second of my sometimes, if you're going to be a good cubeer in the past, you had to learn how to do it, you have to learn how to prepare a cube and do it well, so what that would entail is that you take Separate the cube, already You know, if they're imperfections, you can sand some of that stuff off, lubricate it with a little silicone, let it dry, put each sticker back together, you know, just pay attention to the screws, it was a lot of effort over time.
More manufacturers entered the space, the cubes improved a lot in quality, so kids today don't know how good they have it, as if the improvement in cube technology has caused a change in some of these economies that I showed them. Before there was absolutely no way you could do a spin with this fourth ring finger the way people spin the cube in the you know, the hand movements that people use evolved as a result of cubes getting better, so Mau taught me a method to solve the cube that he shows to beginners by following his instructions.
It took me 45 minutes to solve the cube for the first time. I think if you spend the next two weeks on this you'll probably get your time down to about 90 seconds. 90 seconds. Well, I'm going to try to get to a point where I can solve the cube consistently using the method that Tyson gave me today in less than 90 seconds and we'll see what that's really like, so I grabbed my new cube and started practicing on the First days. She went from meeting for about 20 minutes to solve the cube to just under three—not bad for a novice, but that's still an eternity for someone like Tiffany TN, a local speed cuber who averages just under 10 seconds per solution.
She is so good that she can solve a cube blindfolded. and with one hand I just saw a

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's cube with one hand more than three times faster than I can solve it with you when you pick up a cube you don't look like I look when I pick up a cube, which is like I'm manic in they're not really going full speed oh yeah definitely my hands can definitely move faster than my brain during solving so it's not limited by how fast my hands can move so what my brain can see what my eyes can see, can you too? exercising that kind of restraint throughout the solve, so my remit is definitely to solve it as smoothly as possible, without pauses, because I find that if I try to pivot quickly when I'm nervous, I'll do it very poorly.
I asked him to critique my resolution as slow, one minute and 41 seconds. I'm ashamed. Do you have any advice based on that? For starters, he said he should try to open with a more efficient movement. The second tip is more general for the I noticed that you spend a lot of time spinning the whole cube or using your whole hand to spin the cube, so while you're doing the second one, you see the piece up here, so you do like this. or something like that, but you can see pieces that are on the other side of the cube, so you shouldn't need to do that many rotations of the entire cube, so given what we've learned about the speed of the cube, what is the limit lower than what speed can you?
We're going to find out what helps understand some of the math behind the cube and for that we turned to computer scientist Tom Rick Hickey. There are forty-three billion musicians, which is 43 trillion actually, so that's a really big number that Ruki Key has been around. He was fascinated with the cube since he was a kid and around the turn of the millennium he started pondering one of the cube's big unanswered questions and this is a little confusing at first but stay with me from those 43 quintillion configurations there are some of them like this that are very easy to solve if I gave you the cube in this state you would know that it only takes a moon to solve it, but most of the problems in the tube are much more complicated than that, so the question Ricky wanted answer: what is the maximum number of moves it would take to solve it, no matter how confused it is?
Mathematicians call that figure divinity and it was unknown for more than 30 years until Rick Hickey and his colleagues discovered it. we used a really fast program with all sorts of neat tricks that allowed us to solve about a billion positions per second and then we used a billion seconds of computer time now a billion seconds of computer time sounds like a long time and it really is. It's except if you have thousands of computers, it's a lot less, so what's God's number when it comes to the Rubik's cube? 20, no matter how complicated this problem gets, you're never more than 20 moves away from being completely solved, and it's usually almost less than that.
All positions require less than 20 moves, 18 is the most common, so the typical fight you'll get from your timer will require moves from a team to resolve optimally. Now you'll remember that the world's fastest speed cubes averaged about 10 turns of the cube per second you divide God's number, which remember, is never more than 20 by 10 turns per second and you get solve times of less than two seconds and look here is proof that it is physically possible to solve one in that time, in fact this robot can solve it in less than a second, so from a purely mathematical point of view a human solution in less than two seconds should be possible.
There are only two problems with that line of thinking, firstly, just because a computer can quickly identify the fewest number of moves to solve a cube doesn't mean a human can do magic, there is no one out there who can look at this cube and say ah, I'm eighteen moves away from solving it and this takes me to seventeen, that's just not something humans can do in a second, even if a human could look sharply and quickly identify the fewest number of moves needed to solve it ; It is not known if performing that sequence of moves would be faster than your usual technique, that is because there may be a trade-off between the number of moves it takes to solve a cube and the speed at which you can execute those moves, in Ultimately, solving the cube requires executing finkles physical movements and the faster you can execute those movements, the less time you will need to solve the cube, but it is not as simple as minimizing the number of movements is not what you know, ergonomics and other things come into play, so an example is you know this state and you notice that there are three stickers here that are unresolved.
We call this case u permutation and originally when people were solving.There's a nine move sequence that looked like this and that's how people solve the cube, but over time I mean around 2004 2005 an 11 move sequence became more popular because it was faster to execute, you know you want Minimize the number of moves, but you also want to make those moves quickly, so what do speed cubers think the limits really are? People have asked me to speculate on what the road record will eventually reach and every time I've speculated I've been wrong. I'll try again, you know, you know, I think the low five is probably at least average, you know. , maybe five fixed, as for the limits of a single salt in the next five years, I would probably expect a little less than three seconds.
They gave me enough opportunities in my fist and the single sold time in practice like 301, but then there are a couple of people who did it like day three at home again, quite different. It seems like I could probably make it up to 25, but it's just when will it happen? The fastest times will come down to a combination of luck. Hardware improvements. Development of more efficient methods in a more fluid execution. In my case, for two weeks I carried a Rubik's cube everywhere I went to practice. At least 20 minutes a day I solved my simple. I got it down to 59 seconds and my best average of 5 solutions dropped to one minute and 8 seconds, so I actually made a lot of progress and you probably can too.
I will never compete with any of the fastest speed solvers in the world, that's totally fine because what they are doing is already almost