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

most people are familiar with the Rubik's Cube but very few of them have actually solved it and that's because if you don't know the moves the rubik's cube is one of the most difficult mainstream puzzles ever created frankly the three by three by three is too hard okay it really is now a lot of that has to do with the fact that there are literally billions of billions of ways to scramble this thing but what's equally incredible is that with a few weeks of dedicated practice and a little bit of memorization most people can learn to solve any of those scrambles in a few minutes but there are some people who can solve it even faster a lot faster they're called speed cubers and the best of them can whip a rubik's cube into shape in well under ten seconds is if that weren't impressive enough the single fastest solve ever recorded in competition is a ludicrous three point four seven seconds look at that time go down today we're gonna look at by solving a rubik's cube in under three seconds is almost impossible to find out what it takes I spoke to a world record holder got a crash course in technique from some local speed cubers now the problem here is you notice that things here on the edge don't match problem here is that I don't even see that that's a problem here and talked about the mind-boggling math behind the cube with a computer scientist there are more positions on the Rubik's cubes and there are grains of sand on all the Earth's features the rubik's cube was invented by hungarian architect Erno Rubik in 1974 it actually started out as an experiment Rubick wanted to know if it was possible to design a cube made of smaller blocks that can move independently without falling apart it was only later that he realized he'd also created a puzzle and that puzzle got very popular it wasn't long before people were competing to see who could solve it fastest at the first world rubik's cube championships in 1982 competitors took up to a minute to solve the cube but speed solvers like world record holder felix mpegs have been chipping away at those times ever since I think almost 100 competitions all around the world broken a bunch of world records and won a bunch of grudge one round in competition consists of five solve attempts a computer randomly generates the scrambles to make sure they're difficult enough and each competitor solves the same five scrambles you get asked are you ready I'll take off the cover and then you have option 15 seconds to look at the cube and start the timer so you get that time to look at it then you have to place your hands down on the timer and then fill the cube and then return your hands to like the stack that timer now is probably a good place to mention that diehard cube roots actually care more about average times than single solves fact is sometimes you just get a lucky scramble a better test of a speed cubers skill is to have them solve five cubes and average the three middle times zem DAGs currently holds the average solve record of five point six nine seconds but single solve times still matter and xem Dex used to hold that record too with a time of four point two two seconds that was until Chinese speed cuber you Sheng do demolished it last fall with a time of three point four seven seconds so how unexpected was it for somebody to come along and break your single solve record by like 3/4 of a second that was pretty unexpected to be honest like in in speed cubing you don't often see those sorts of insane jumps in time you can still get a really incredibly quick solve just on one attention if you have an easy scramble and a big block and it just so happened that you know there's so many people going to so many competitions all the time that something like this was probably bound to happen but we didn't really expect it that soon okay so let's put speed cubing aside for a second because a lot of people myself included have never solved the Rubik's Cube at all in any amount and that's because truly solving one like from scratch without any help from anybody without watching any online tutorial videos it's really really hard the truth is if you see somebody solving a Rubik's Cube they are almost definitely using a memorized sequence of moves to do it this is Tyson Mao he's 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 fast at solving the cube the first one is the method there are many methods for solving a cube but they all rely on something that cubers call algorithms memorize sequences of moves that players use to solve the cube section-by-section now as a rule of thumb the more algorithms you know the fewer moves you'll need to solve the cube a beginner who has committed fewer than 10 algorithms to memory might solve a cube and say 120 moves while an expert who has memorized hundreds of algorithms can solve the cube and closer to 50 or 60 moves and as you might expect fewer moves can translate to faster solves the second thing that contributes to is you know how allah' teaches all the cube is how fast you can turn the cube the fastest speed cubers in the world averaged around 10 turns per second over the course of an entire song and a lot more than that in shortened versions take this 16 move finishing sequence for example it looks like this 1 2 3 4 with this ring finger 5 6 7 8 and now you gotta push back with this ring finger 9 10 11 12 pull 13 14 15 16 push the top people can execute those 16 moves in under one second are you serious that's amazing the third thing that contributes to how long it takes to solve the cube is how long it takes you to processed 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 for the next step are while you're doing the current one and reducing a pause between those steps and then there's the hardware itself as you can see there are lots of different types of 3x3 cubes from the old-school version which was clunky stiff and hard to turn to fancy new models that spin with ease and include tiny magnets to help the faces snap into position the actual hardware itself is involved to the point now where it's like it's really really good like if you give me a cube from five years ago it's probably taking off like a second off my sometimes if you're going to be a good cube er back in the day you had to learn how to make you have to learn how to prepare a cube and make it good and so what that would involve is you take the cube apart you know if they're imperfections you might sand some of those things down you lubricate it with some silicone let it dry put it back together every sticker you know just attention on the screws it was it was a big effort over time as more manufacturers entered the space cubes just got a lot better than quality so the kids these days they don't know how good they have it like the improvement in the cube technology has caused a change in some of these economics that move that I showed you earlier there was absolutely no way you could make a turn with this fourth ring finger the way that people turn 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 for solving the cube that he shows the beginners following his instructions it took me 45 minutes to solve the cube for my very first I think if you spent the next two weeks on this you probably get your time down to about 90 seconds 90 seconds okay I'm gonna try to get to a point where I can solve the cube consistently using the method Tyson was giving me today in under 90 seconds and we'll see how is that actually so I took my new cube and got to practicing in the first few days I went from meeting around 20 minutes to solve the cube to just under three not bad for a newbie but that's still an eternity for someone like Tiffany TN a local speed cuber who averages just under 10 seconds per solve she's so good she can solve a cube blindfolded and one handed just saw a rubik'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 the way I look when I pick up a cube which is like it's manic you are actually not going full-tilt oh yes definitely my hands can definitely move faster than like my brain can during the solve so it's limited not by how fast my hands can move then like what my brain can see what my eyes can see so are you exercising that kind of restraint throughout the entirety of it solve so my in competition is definitely to like solve it as smoothly as possible like with no pauses because I find that if I try to turn quickly when I'm nervous I'll turn very poorly I had her critique my solving damn as a slow one one minute 41 seconds I'm ashamed okay so do you have any tips based on that for starters she said I should try opening with a more efficient move the second tip is more general for the entire self I noticed that you spend a lot of time like turning the whole cube around or like using your whole hand to turn the cube around so like during while you're doing the second there you see the piece up here so you go like this or something but you can see pieces that are like on the other side of the cube so you shouldn't need to do so many rotations of the whole cube so given what we've learned about speed cubing what is the lower limit how fast can we go to figure that out it helps to understand some of the math behind the cube and for that we turn to computer scientist Tom Rick Hickey there's forty-three billion billion musicians which is 43 quintillion right so it's really a big number Ruki key has been fascinated with the cube ever since he was a kid and around the turn of the millennium he started puzzling over one of the great unanswered questions of the cube and this is a little confusing at first but stick with me of those 43 quintillion configurations there are some of them like this that are very easy to solve if I handed you the cube in this state you'd know that it takes just one moon to resolve it but most of the scrambles on the tube are a lot more complicated than that so the question Ricky wanted to answer was this what is the maximum number of moves that would ever be required to solve you no matter how scrambled it is mathematicians call that figure godness and it went unknown more than 30 years until rick hickey and his colleagues figured it out we used a really fast program with all sorts of clever tricks that let us solve about a billion positions a second and then we used a billion seconds of computer time now a billion seconds of computer time sounds like a long time and really it is except for if you've got thousands of computers it's a lot less so what is God's number when it comes to the Rubik's Cube 20 no matter how complicated this scramble gets you are never more than 20 moves away from being completely solved and it's usually less than that almost all positions require fewer than 20 moves 18 is the most common so your typical scramble you're going to get from your timer it's going to take a team moves to solve optimally now you'll remember that the fastest speed cubers on earth 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 solved times of under two seconds and look here's proof that it is physically possible to solve one in that time in fact this robot can solve it in under one second so from a purely mathematical standpoint a sub two-second solved by a human should be possible there's just two problems with that line of thinking first of all just because a computer can quickly identify the fewest number of moves to solve a cube doesn't mean a human can magic there's nobody out there that can look at this cube and say ah I'm eighteen moves from solved and this one takes me to seventeen that's just not something which humans can do in second even if a human could look at acute and quickly identify the fewest number of moves required to solve it there's no telling whether performing that sequence of moves would be any faster than their usual technique that's because there can 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 ultimately solving the cube requires executing finkles physical moves and the faster that you can execute those moves the less time it needs to solve the cube but it's not as simple as minimizing the number of moves it is not you know ergonomics and other things come into play so one example is you know this state which we you notice that there are three stickers here that are not solved we call this case the u permutation and originally when people were solving this there is a nine move sequence that that looked like this and this is how people solve the cube but then over time I want to say around 2004 2005 an 11 move sequence became more popular because it was just faster to execute you know you want to minimize the number of moves but you also want to be to make those moves quickly so what do speed cubers think the limits actually are people have asked me to speculate what the road record will eventually reach and every time I speculated I've been wrong so I'll take another shot at it again you know you know I think low fives is probably at least from an average you know maybe five flat as for the limits of a single salt in the next five years I would expect probably something under three seconds given just enough chances on my fist and the single sold time in practices like 301 but then there's a couple people who've done like on day three at home again just pretty much different I look like probably I could do it to 25 but it's just when will it happen faster times will come down to a combination of luck improvements in hardware the development of more efficient methods in smoother execution as for me for two weeks I brought a Rubik's Cube with me everywhere I went the practice at least 20 minutes a day I got my single solved I'm down to 59 seconds and my best 5 solution average down to one minute 8 seconds so actually made a ton of progress and you probably could too well I'm never going to compete with any of the world's fastest speed solvers that's totally fine because what they're doing is already almost impossible [Music]

Channel: WIRED

Views: 7,023,674

Rating: 4.8901024 out of 5

Keywords: rubik's cube, tyson mao, tiffany chien, speed cubing, speed cube, 3x3 cube, felix zemdegs, competitive cubing, tomas rokicki, tom rokicki, fastest cuber, fastest rubik's, fastest rubik's cube, fastest solve, rubiks cube, rubiks, erno rubik, rubiks cube solve, solving a rubiks cube, rubiks cube solving, how to solve a rubiks cube, rubiks cube solution, fastest rubiks cube, rubiks cube world record, rubiks cube record, cubing, rubiks cube competition, wired

Id: SUopbexPk3A

Length: 14min 57sec (897 seconds)

Published: Fri May 24 2019

Reddit Comments

[u/dm_me_it_will_be_ok]

Not with that attitude

[u/_Skitttles]

I love this series. There have been a few episodes on topics that I know a lot about and they're always super well made and properly informed. It makes me feel confident in other episodes where I have no clue what's going on.

[u/DellSalami]

Pretty solid video. I kinda wish they talked about FMC during the whole god's numbee segment though.

Also funny that they uploaded this after the WB solidly got under 3 seconds.

[u/BeepBeepImASheep023]

8:07. I think that's TC Kewbz! Sounds like her, I assumed she was Asian, and I believe the comp vid she's posted was from up in Berkley area

Anyone confirm?

[u/BruhFortniteLaggyTho]

Why do I feel nice that I was in the video. Not physically though. The clips with Tiffany in the building was in my first ever competition two weeks ago (Bay Area Speedcubin’ 16 2019). I am about to head off to Carmichael for SacCubing VII 2019.

I saw that camera that was used to record and thought, what is that. Then I came across this post. I noticed the background and her. And that one particular judge who was judging her solve.

I feel good that I was in the same environment, but not necessarily in the actual video.

Man, that comp was fun.

[u/dycocubix]

Really well made video with lots of well done research unlike other videos made about cubing.

[u/Almaironn]

That's very interesting, the part about cube technology getting better. I used to cube back in 2011 and I own a Lubix Zhanchi. The guy in the video seemed to imply that having to take your cube apart and lubricate it is a thing of the past? And cubes with magnets? I'm getting excited, maybe I should get one of these new cubes and give it a go again.

[u/TalenPhillips]

This is actually a surprisingly good video about speedcubing.

They really did their homework. I'm impressed.

[u/dogetripwire]

Is it tho?