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Tags Rubik's Cubes

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Old 6th March 2019, 04:20 PM   #1
Minoosh
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A question about Rubik's cube

I keep a Rubik's cube on hand as a way to pacify hyperactive children, but it's counterproductive: They get so caught up in the puzzle that I can't get them to focus on reading, or whatever it is they're supposed to be focusing on.

I had a very fidgety kid yesterday who wanted to "solve" the cube by peeling off the labels and rearranging them so the cube was solved. It got me thinking:

If I had allowed him to do this, would it have compromised the puzzle at all?

The combinations/permutations are in the quadrillions, I saw on YouTube. It would take a trillion years to make all of them at which point we'd all be dead anyway and there wouldn't be any light to see the colors. But: Assuming there is only one permutation that "solves" the cube, could I then make a few twists and still have the original puzzle? I would know it could be solved, and the quadrillion-something permutations would quickly reassert themselves.

Would it be the same as having a new cube from the factory?
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Old 6th March 2019, 04:24 PM   #2
mgidm86
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It would not ruin the cube. The cube without anything "rotated" is physically the same no matter what has been rotated. If that makes sense. If not, see first sentence

ETA: I used to be able to solve it in less than a minute.
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Old 6th March 2019, 04:28 PM   #3
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Like mgi said: it would just reset the starting point but it wouldn't be any different after that.
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Old 6th March 2019, 04:33 PM   #4
sir drinks-a-lot
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If I understand your question correctly, you're asking if you take a scrambled cube and peel off the stickers and place them to solve the cube whether the cube would be the same as an original unscrambled cube. If that's the question, the answer is yes!

It is interesting to note that when you are solving the cube, the center square on each of the six sides is what determines what color that face will be. Your only job is to move the rest of the pieces (which are either two colored or three colored) into the proper orientations and positions.
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Old 6th March 2019, 04:33 PM   #5
BowlOfRed
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For most cubes, it's easier to pop the cubes apart and put it back together correctly. If you take the stickers off, they get dirty and don't stick as well.

In both cases, as long as you reassemble/resticker to a solved cube at the end, you're fine. If you put it back randomly, it may not be possible to solve just by twisting.
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Old 6th March 2019, 04:34 PM   #6
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I think you could ruin one by moving the stickers - just putting the same colour on two of the centre squares would do it, but not if the stickers were replaced with the cube solved.

I do rather like the lateral thinking of the kid, he should get bonus marks.

I didn't take the stickers off mine to solve it. You can lever them apart with a screwdrivver though...
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Old 6th March 2019, 05:00 PM   #7
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Originally Posted by BowlOfRed View Post
For most cubes, it's easier to pop the cubes apart and put it back together correctly. If you take the stickers off, they get dirty and don't stick as well.
This has been my experience as well. Disassembly is far better.

Fred
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Old 6th March 2019, 05:07 PM   #8
arthwollipot
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Originally Posted by BowlOfRed View Post
For most cubes, it's easier to pop the cubes apart and put it back together correctly. If you take the stickers off, they get dirty and don't stick as well.

In both cases, as long as you reassemble/resticker to a solved cube at the end, you're fine. If you put it back randomly, it may not be possible to solve just by twisting.
Yeah, if you do that a lot, the stickers fall off, which makes the cube a lot harder to solve.
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Old 6th March 2019, 05:22 PM   #9
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Originally Posted by arthwollipot View Post
Yeah, if you do that a lot, the stickers fall off, which makes the cube a lot harder to solve.
Well, not if they all come off...

I have yet to solve one in the 30+ years I've been trying.
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Old 6th March 2019, 05:29 PM   #10
theprestige
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Originally Posted by alfaniner View Post
Well, not if they all come off...



I have yet to solve one in the 30+ years I've been trying.
Apparently the method is a simple sequence of rote gestures.
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Old 6th March 2019, 05:31 PM   #11
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I can solve one, but only because of learning some rules several decades ago.

I never really understood how to make progress on such a thing on my own. But then I watched a Mathologer video.
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I can't say that I've actually used it to solve anything, but I really liked understanding the concept he showed.
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Old 6th March 2019, 05:33 PM   #12
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Yeah, the actual solution is tedious to execute. And it appears very few people actually figure it out for themselves.
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Old 6th March 2019, 06:50 PM   #13
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So if you remove stickers to "reset" the cube, then no, it will not affect the cube.

If you randomly remove/replace stickers, it will mess it up. If you replaced the colored stickers of a cube and replaced them with numbers so it would look like a giant die, (like https://www.instructables.com/id/Mag...k-s-Dice-Cube/ ), you could make the puzzle unsolvable. You could have a middle edge piece showing 1 and 6. Since those two numbers will never share an edge, just like a real die, you just "broke" the cube.
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Old 6th March 2019, 09:33 PM   #14
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The easiest way to solve the cube is to use six colors of paint and a small paintbrush.
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Old 6th March 2019, 10:58 PM   #15
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If you want to calm kids, there are fidgety cube toys that fit in one hand, leaving the other free to draw/write/turn pages.
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Old 6th March 2019, 10:59 PM   #16
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If you want to solve a cube without a screwdriver, there are many programs where you put in the current constellation and it outputs the necessary steps.
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Old 6th March 2019, 11:16 PM   #17
lionking
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Originally Posted by Myriad View Post
Yeah, the actual solution is tedious to execute. And it appears very few people actually figure it out for themselves.
Well I can honestly say I figured it out myself. I bought one soon after the craze started, and it took me months and a very sore wrist to solve it. After that I could usually solve it in about 3 or 4 minutes. If I were given one now, it would probably take me weeks as I have forgotten the strategy I used.
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Old 7th March 2019, 12:14 AM   #18
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I've tried. I was able to solve two layers by following a formula, but couldn't internalise the formula for the third layer. I could do it step by step, but I could never do it without referring to notes.
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Old 7th March 2019, 01:58 AM   #19
Dave Rogers
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Originally Posted by arthwollipot View Post
Yeah, if you do that a lot, the stickers fall off, which makes the cube a lot harder easier to solve.
FTFY.

Originally Posted by BowlOfRed View Post
In both cases, as long as you reassemble/resticker to a solved cube at the end, you're fine. If you put it back randomly, it may not be possible to solve just by twisting.
It's possible, if I recall correctly, to reverse the orientation of any two side cubes without changing anything else; there are therefore two possible arrangements of the side cubes that are not equivalent. Similarly it is possible to rotate any two corner cubes in opposite directions without changing anything else, so in effect there are only three possible arrangements of the corner cubes that are not equivalent. Multiplying those together indicates that, if you take a cube apart and then reassemble it completely randomly, there is a 1/6 probability that this will result in a soluble cube.

I bet you all wanted to know that.

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Old 7th March 2019, 02:55 AM   #20
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Originally Posted by Dave Rogers View Post
FTFY.



It's possible, if I recall correctly, to reverse the orientation of any two side cubes without changing anything else; there are therefore two possible arrangements of the side cubes that are not equivalent. Similarly it is possible to rotate any two corner cubes in opposite directions without changing anything else, so in effect there are only three possible arrangements of the corner cubes that are not equivalent. Multiplying those together indicates that, if you take a cube apart and then reassemble it completely randomly, there is a 1/6 probability that this will result in a soluble cube.

I bet you all wanted to know that.

Dave
Actually the cube will always be 100% as soluble as before you started.
There is probably only a 1 in 6 probability of it being solvable though
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Old 7th March 2019, 03:05 AM   #21
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Originally Posted by Guybrush Threepwood View Post
Actually the cube will always be 100% as soluble as before you started.
There is probably only a 1 in 6 probability of it being solvable though
From Wiktionary:

Adjective[edit]

soluble (comparative more soluble, superlative most soluble)
1.Able to be dissolved. Sugar is soluble in water.
2.Able to be solved or explained. That mystery should be easily soluble.



Dave
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Me: So what you're saying is that, if the load carrying ability of the lower structure is reduced to the point where it can no longer support the load above it, it will collapse without a jolt, right?

Tony Szamboti: That is right
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Old 7th March 2019, 03:35 AM   #22
Guybrush Threepwood
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Originally Posted by Dave Rogers View Post
From Wiktionary:

Adjective[edit]

soluble (comparative more soluble, superlative most soluble)
1.Able to be dissolved. Sugar is soluble in water.
2.Able to be solved or explained. That mystery should be easily soluble.



Dave
Indeed, I did not know that
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Old 7th March 2019, 04:48 AM   #23
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I could never work out how to solve it myself, but used to have a book (in the days before the internet) that gave a strategy for solving and I learned how to do it and could do it in 2-3 minutes. I have no recollection on how to do it now.
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Old 7th March 2019, 04:53 AM   #24
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Originally Posted by Shankly View Post
I could never work out how to solve it myself, but used to have a book (in the days before the internet) that gave a strategy for solving and I learned how to do it and could do it in 2-3 minutes. I have no recollection on how to do it now.
Same here. But I think people who solve it really quickly have a very different strategy, which I just can't fathom.

Dave
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Tony Szamboti: That is right
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Old 7th March 2019, 08:35 AM   #25
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If you do want to mess up a cube so it's unsolvable, just swap two of the stickers on just one of the corner or edge pieces (or pop the piece out and put it back in a different orientation).
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Old 7th March 2019, 09:24 AM   #26
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I've seen Adam Savage and Jamie Hyneman solve them, one using his feet and the other while blindfolded.

They started with solved cubes, messed them up, and ran the footage backward. Even had people walk backward through the set behind them to make it look better.
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Old 7th March 2019, 09:26 AM   #27
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Originally Posted by phunk View Post
If you do want to mess up a cube so it's unsolvable, just swap two of the stickers on just one of the corner or edge pieces (or pop the piece out and put it back in a different orientation).
Or swap two adjacent face centres.

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Tony Szamboti: That is right
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Old 7th March 2019, 09:49 AM   #28
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Originally Posted by Dave Rogers View Post
Or swap two adjacent face centres.

Dave
If you do that to me, I might notice quickly that its wrong (because the orientation won't match some of the corner cubes). But if you flip an edge, I have to wait until the end to realize that it's wrong.
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Old 7th March 2019, 11:45 AM   #29
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Originally Posted by Trebuchet View Post
I've seen Adam Savage and Jamie Hyneman solve them, one using his feet and the other while blindfolded.

They started with solved cubes, messed them up, and ran the footage backward. Even had people walk backward through the set behind them to make it look better.
My favorite is the kid (from Japan, I think) who solved three Rubik's cubes simultaneously - while juggling them. It took him about 10 minutes.

So he was juggling them, and while the cube was in his hand, he would make a turn or two.

The dumbest thing about it was that he "broke the record" for the fastest time to solve three Rubik's cubes while juggling them, which means that...someone had already done it, albeit in a slower time.

Then again, it may have been his own record that he broke.
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Old 7th March 2019, 04:39 PM   #30
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Originally Posted by Dave Rogers View Post
FTFY.
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Old 8th March 2019, 02:22 PM   #31
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Originally Posted by Trebuchet View Post
I've seen Adam Savage and Jamie Hyneman solve them, one using his feet and the other while blindfolded.

They started with solved cubes, messed them up, and ran the footage backward. Even had people walk backward through the set behind them to make it look better.
I like this! It mimics the scenario I proposed.

I've been following YouTube instructions in my free time for a couple of days now, but I'm stuck.
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Old 8th March 2019, 02:40 PM   #32
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Old 8th March 2019, 07:33 PM   #33
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It's really bothering me that I can't seem to understand various online tutorials. If there is such a thing as "spatially challenged" I may qualify.

Oh well. I am quite stubborn so I'll figure it out eventually. Maybe it can be a brain-builder.
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Old 9th March 2019, 07:48 AM   #34
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Originally Posted by phunk View Post
If you do want to mess up a cube so it's unsolvable, just swap two of the stickers on just one of the corner or edge pieces (or pop the piece out and put it back in a different orientation).
You know, I'm beginning to suspect that one of my visiting nephews did this several years ago which is why I haven't been able to solve it. Maybe I should buy a new one.
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Old 9th March 2019, 09:07 AM   #35
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Originally Posted by Minoosh View Post
It's really bothering me that I can't seem to understand various online tutorials. If there is such a thing as "spatially challenged" I may qualify.

Oh well. I am quite stubborn so I'll figure it out eventually. Maybe it can be a brain-builder.
I found this one to be relatively simple compared to other tutorials, I didn't watch the vids though, just followed the instructions.

https://www.youcandothecube.com/solve-it/3-x-3-solution

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Old 9th March 2019, 11:40 AM   #36
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Originally Posted by Minoosh View Post
I had a very fidgety kid yesterday who wanted to "solve" the cube by peeling off the labels and rearranging them so the cube was solved. It got me thinking:

If I had allowed him to do this, would it have compromised the puzzle at all?

......

But: Assuming there is only one permutation that "solves" the cube, could I then make a few twists and still have the original puzzle? I would know it could be solved, and the quadrillion-something permutations would quickly reassert themselves.
It is perfectly possible to relabel the faces to produce a "solved" cube which cannot be manipulated to recreate the original.

If you swap any two adjacent faces' colors, the original geometry cannot be recovered.

Let's say you have one face red and the opposite face blue. If you swap the blue face with any of the other four faces, it is "pinned" to the red face by the edge and corner faces and cannot be solved to return it to the opposite face.
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Old 9th March 2019, 12:54 PM   #37
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Originally Posted by BowlOfRed View Post
For most cubes, it's easier to pop the cubes apart and put it back together correctly. If you take the stickers off, they get dirty and don't stick as well.

In both cases, as long as you reassemble/resticker to a solved cube at the end, you're fine. If you put it back randomly, it may not be possible to solve just by twisting.
Indeed, putting, say a white on each centre point, or on both/all sides of an edge/corner would do that.
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Old 9th March 2019, 01:09 PM   #38
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Originally Posted by WhatRoughBeast View Post
It is perfectly possible to relabel the faces to produce a "solved" cube which cannot be manipulated to recreate the original.

If you swap any two adjacent faces' colors, the original geometry cannot be recovered.

Let's say you have one face red and the opposite face blue. If you swap the blue face with any of the other four faces, it is "pinned" to the red face by the edge and corner faces and cannot be solved to return it to the opposite face.
Yes, this occurred to me when I made my first serious effort to solve the puzzle (this week). Knowing white is opposite yellow from the factory, I could see that the common algorithms found online would no longer work. But it did seem to me it would still be solvable, just not by using step-by-step instructions that assume that yellow is opposite white as in a newly minted cube.
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Old 10th March 2019, 06:21 PM   #39
arthwollipot
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Douglas Hofstadter devoted two whole chapters to the Cube in his book Metamagical Themas. If you want serious full-on cube nerdery, I suggest picking up a copy.
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Old 10th March 2019, 06:56 PM   #40
WhatRoughBeast
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Originally Posted by Minoosh View Post
Yes, this occurred to me when I made my first serious effort to solve the puzzle (this week). Knowing white is opposite yellow from the factory, I could see that the common algorithms found online would no longer work. But it did seem to me it would still be solvable, just not by using step-by-step instructions that assume that yellow is opposite white as in a newly minted cube.
Sorry, no. Please reread my answer. In the case I gave, the blue face is fixed to the red by 3 pieces which share red and blue. Therefore, any solution must have red and blue adjacent, and red and blue can never be on opposite faces.
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