
New deep learning technique solves Rubik's Cube without assistance - rbanffy
https://www.technologyreview.com/s/611281/a-machine-has-figured-out-rubiks-cube-all-by-itself/
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peapicker
Inaccurate article on one point - they say that in 2014 it was proved the
smallest number of moves to solve is 26... but in 2010 it was proven to be 20
moves actually. [1]. (And the article they linked to was from 2008 anyway and
said that 25 moves was the max needed as of 2008 best knowledge)

They probably were referring to the "quarter turn metric" which is 26 quarter-
turn moves, but "moves" in speedcubing almost always refers to face turns. And
this is made more confusing by the article since the article they linked to
was regarding face turns as well.

Both of course are mentioned at cube20.org [2]...

[1]
[https://www.bbc.com/news/technology-10929159](https://www.bbc.com/news/technology-10929159)

[2] [http://www.cube20.org/](http://www.cube20.org/)

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JulianWasTaken
I suppose the answer might be in the actual article, but

> In chess, by contrast, there is a relatively large search space but each
> move can be evaluated and rewarded accordingly. That just isn’t the case for
> the Rubik’s Cube.

I don't follow this at all -- how do you reward an individual chess move other
than by using a reward system that may or may not be anywhere near fully
accurate like counting material? Seems pretty similar to solving a Rubik's
cube.

~~~
joe_the_user
Most chess solvers definitely use material count and similar "simplistic"
heuristics. I don't know of any similar heuristics for a rubik's cube.

[https://en.wikipedia.org/wiki/Computer_chess#Leaf_evaluation](https://en.wikipedia.org/wiki/Computer_chess#Leaf_evaluation)

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CJKinni
I know it's too much to ask, and this accomplishment is impressive, but when I
read the headline I thought that solving Rubik's Cube 'without assistance'
might mean building a mechanical apparatus to solve the cube.

~~~
earenndil
Those do exist, though, and could probably be connected to such an algorithm
as this one.

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rwnspace
Interesting how the solver preferred to build a 2x2x2 block and then
match/solve pairs until it could then apply ABA' sequences (commutators in
cubing parlance). Very reminiscent of something between Lars Petrus' and Ryan
Heise's method. There's a more rigid version called Tripod.

As an avid speedcuber I'd be very interested in the datasets.

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partycoder
[https://arxiv.org/pdf/1805.07470.pdf](https://arxiv.org/pdf/1805.07470.pdf)

Results are compared with known optimal algorithms for the Rubik's cube:
Kociemba's algorithm, Korf's algorithm.

[https://en.wikipedia.org/wiki/Optimal_solutions_for_Rubik%27...](https://en.wikipedia.org/wiki/Optimal_solutions_for_Rubik%27s_Cube)

~~~
black_puppydog
_please_ , link to arxiv abstracts, not directly to the pdf.

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bwasti
Why request this? Is there some common wisdom here I’m missing? You should
probably include the reason or else this just seems like a weirdly petty
request

~~~
backpropaganda
PDFs are hard to read on phone. The abstract page is better if you just want
to read abstract. Some PDFs can also contain large images, which is again bad
for mobile if you only really wanted to read abstract.

~~~
slobotron
We need AMP/PWA for PDFs!

~~~
backpropaganda
We sort of do for arxiv: [https://www.arxiv-vanity.com/](https://www.arxiv-
vanity.com/)

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letitgo12345
Ugh, I'm tired of every new ML idea being described as a "deep learning
technique". Yeah they use neural networks but the idea is not NN specific.

Other than that, awesome paper.

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Gys
Dupe. I assumed HN checks if an article with the same link was already
submitted ?

This exact same article / link was already posted a day ago:
[https://news.ycombinator.com/item?id=17320218](https://news.ycombinator.com/item?id=17320218)

Plus another link, plus the original research link.

~~~
detaro
It only checks for a short time in the past, since duplicate submissions are
explicitly allowed when the previous submission didn't have a discussion/many
upvotes.

