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If you've never learnt the algorithms required to solve a Rubik's cube-- don't. Understanding and solving a cube by brute effort is a great little challenge to

If you've never learnt the algorithms required to solve a Rubik's cube-- don't. Understanding and solving a cube by brute effort is a great little challenge to come back to over the years.

aivisol 6y ago
Because once you learn them, you will never unlearn. I took a cube in my hands after some 30+ years break and my hands just instantly knew the sequences...
- mgkimsal 6y ago
  I remember about 80% of them by muscle memory, but... I've forgotten some, so my party trick now is to get a cube 'nearly' solved in about 50 seconds, then give it to someone else, and say "I've done all the hard work already, you can finish it off".
- srtjstjsj 6y ago
  Generally that's true for things learned as children, not as adults.
- cableshaft 6y ago
  I managed to forget most of them after about 5 years of not doing it. I can intuitively get the first two layers now, but the top seems too difficult without knowing the sequences. I like messing about with a Megaminx also, and it's the same for that. I can get the first couple of layers just thinking about it intuitively, but then I get stuck on the top layer. At some point I'll relearn the sequences again, but I haven't yet. Also picked up a 2x2 cube recently, and that one has me pretty stumped. You'd think it'd be easier to figure out but I haven't figured it out yet.
kamaal 6y ago
Apart from the fact that you get the happiness of having solved it without help. What else does it give?
- wyattpeak 6y ago
  Probably not much. A bit more intuition about non-commutative transforms, perhaps. But you don't gain anything much from learning to solve them either. It's a fun party trick once or twice, but you'll likely feel uncomfortable not acknowledging that you read the answer, at which point it's comparatively unimpressive.
  - UweSchmidt 6y ago
    Is there any game or challenge that actually makes you smarter or better or helps you out in any practical way?
    - 082349872349872 6y ago
      Depends upon what one considers practical? I had some nice (here: both informative and entertaining) conversations with someone I'd consider a genius, not via the more evidently practical skill of juggling, but because we'd made each others' acquaintance due to a mutual interest in Rubik's Cube.
      - Someone 6y ago
        If you haven’t seen it, you may be interested in https://youtube.com/watch?v=q6AsllXpKBU https://youtube.com/watch?v=q6AsllXpKBU, which combines solving Rubik’s cube with juggling (1 minute, 41 seconds per cube)
    - monsieurbanana 6y ago
      Of course. Games like go can help reduce the effects of Alzheimer[1]. I'm sure there are studies for chess too. Sports are games with obvious health, mental and social benefits. On a more intuitive level (aka I don't know if it's been researched), I would be surprised if most board games don't improve, at least a bit, the analytical thinking useful for many engineering fields (or even day to day life). Challenges is a term too broad, you can imagine countless ones that have practical benefits. Learning-to-play-an-instrument-in-a-month challenge for example. 100 push-ups a day for a month. Read one book a month. [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4548213/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4548213/
082349872349872 6y ago
If you have learned them, it's not too late. Martin Gardner mentioned an algorithm that doesn't work layer by layer, but instead starts off with all manipulations available, and gradually restricts which ones are admissible. In principle, just at the point no moves are admissible, the cube is also solved. In that oh so distant future when I have nothing else to do, I'd like to try to work out this approach for myself.
- Sephiroth87 6y ago
  Sounds interesting, do you have any source on this? tried googling but couldn't find anything...
  - 082349872349872 6y ago
    I messed up. Upon referring to http://martin-gardner.org/MGSAindex.html http://martin-gardner.org/MGSAindex.html , I've learned it was a Hofstadter column: https://www.scientificamerican.com/article/metamagical-themas-1981-03/ https://www.scientificamerican.com/article/metamagical-thema... (paywalled) Does http://www.math.rwth-aachen.de/~Martin.Schoenert/Cube-Lovers/Jerry_Bryan__Re__I_am_in_search_of_Thistlewaite%27s_algorithm.html http://www.math.rwth-aachen.de/~Martin.Schoenert/Cube-Lovers... provide enough information? (At least it gives you some better search terms.) > "indeed it is not visually obvious that any progress at all is being made until the cube is almost solved."
- dunham 6y ago
  I do the edges first and then the corners. I changed it up for novelty and to force myself to come up with a different solution. So I've got permutations to manipulate edges that also mess with the corners, followed by ones that manipulate the corners. I've wondered if there is a way to do it by restricting to smaller and smaller subgroups, but that'd probably be a lot of work to figure out.
cdelsolar 6y ago
I have a cube sitting on my desk; it helps me think. Over time I've learned more and more algorithms for it; I almost know all the PLLs. Honestly it's a lot of fun!

If you've never learnt the algorithms required to solve a Rubik's cube-- don't. Understanding and solving a cube by brute effort is a great little challenge to come back to over the years.

aivisol 6y ago

Because once you learn them, you will never unlearn. I took a cube in my hands after some 30+ years break and my hands just instantly knew the sequences...

mgkimsal 6y ago
I remember about 80% of them by muscle memory, but... I've forgotten some, so my party trick now is to get a cube 'nearly' solved in about 50 seconds, then give it to someone else, and say "I've done all the hard work already, you can finish it off".
srtjstjsj 6y ago
Generally that's true for things learned as children, not as adults.
cableshaft 6y ago
I managed to forget most of them after about 5 years of not doing it. I can intuitively get the first two layers now, but the top seems too difficult without knowing the sequences. I like messing about with a Megaminx also, and it's the same for that. I can get the first couple of layers just thinking about it intuitively, but then I get stuck on the top layer. At some point I'll relearn the sequences again, but I haven't yet. Also picked up a 2x2 cube recently, and that one has me pretty stumped. You'd think it'd be easier to figure out but I haven't figured it out yet.

kamaal 6y ago

Apart from the fact that you get the happiness of having solved it without help. What else does it give?

wyattpeak 6y ago
Probably not much. A bit more intuition about non-commutative transforms, perhaps. But you don't gain anything much from learning to solve them either. It's a fun party trick once or twice, but you'll likely feel uncomfortable not acknowledging that you read the answer, at which point it's comparatively unimpressive.
- UweSchmidt 6y ago
  Is there any game or challenge that actually makes you smarter or better or helps you out in any practical way?
  - 082349872349872 6y ago
    Depends upon what one considers practical? I had some nice (here: both informative and entertaining) conversations with someone I'd consider a genius, not via the more evidently practical skill of juggling, but because we'd made each others' acquaintance due to a mutual interest in Rubik's Cube.
    - Someone 6y ago
      If you haven’t seen it, you may be interested in https://youtube.com/watch?v=q6AsllXpKBU https://youtube.com/watch?v=q6AsllXpKBU, which combines solving Rubik’s cube with juggling (1 minute, 41 seconds per cube)
  - monsieurbanana 6y ago
    Of course. Games like go can help reduce the effects of Alzheimer[1]. I'm sure there are studies for chess too. Sports are games with obvious health, mental and social benefits. On a more intuitive level (aka I don't know if it's been researched), I would be surprised if most board games don't improve, at least a bit, the analytical thinking useful for many engineering fields (or even day to day life). Challenges is a term too broad, you can imagine countless ones that have practical benefits. Learning-to-play-an-instrument-in-a-month challenge for example. 100 push-ups a day for a month. Read one book a month. [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4548213/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4548213/

082349872349872 6y ago

If you have learned them, it's not too late. Martin Gardner mentioned an algorithm that doesn't work layer by layer, but instead starts off with all manipulations available, and gradually restricts which ones are admissible. In principle, just at the point no moves are admissible, the cube is also solved. In that oh so distant future when I have nothing else to do, I'd like to try to work out this approach for myself.

Sephiroth87 6y ago
Sounds interesting, do you have any source on this? tried googling but couldn't find anything...
- 082349872349872 6y ago
  I messed up. Upon referring to http://martin-gardner.org/MGSAindex.html http://martin-gardner.org/MGSAindex.html , I've learned it was a Hofstadter column: https://www.scientificamerican.com/article/metamagical-themas-1981-03/ https://www.scientificamerican.com/article/metamagical-thema... (paywalled) Does http://www.math.rwth-aachen.de/~Martin.Schoenert/Cube-Lovers/Jerry_Bryan__Re__I_am_in_search_of_Thistlewaite%27s_algorithm.html http://www.math.rwth-aachen.de/~Martin.Schoenert/Cube-Lovers... provide enough information? (At least it gives you some better search terms.) > "indeed it is not visually obvious that any progress at all is being made until the cube is almost solved."
dunham 6y ago
I do the edges first and then the corners. I changed it up for novelty and to force myself to come up with a different solution. So I've got permutations to manipulate edges that also mess with the corners, followed by ones that manipulate the corners. I've wondered if there is a way to do it by restricting to smaller and smaller subgroups, but that'd probably be a lot of work to figure out.

cdelsolar 6y ago

I have a cube sitting on my desk; it helps me think. Over time I've learned more and more algorithms for it; I almost know all the PLLs. Honestly it's a lot of fun!