# So, we are at 25. 5 to go?



## badmephisto (Mar 27, 2008)

it was 26 just a few months ago, now they were able to prove that it is lower than that. My guess is that the answer is 20. It must be. The superflip has a beautiful symmetry to it... it would make perfect sense.


http://arxiv.org/abs/0803.3435


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## Dene (Mar 27, 2008)

Yea, I should think 20 would be the upper bound.


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## Stefan (Mar 27, 2008)

What's your .5 good for?


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## Johannes91 (Mar 27, 2008)

It's also on slashdot: http://science.slashdot.org/science/08/03/26/2237221.shtml. It links to this blog, which has some dumb mistakes:


> He’s shown that there are no configurations that can be solved in 26 moves


s/can be solved in/require/



> ... it’s also known that there are no configurations that can be solved in 21 moves.


?


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## MiloD (Mar 27, 2008)

StefanPochmann said:


> What's your .5 good for?



two sentances


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## badmephisto (Mar 27, 2008)

StefanPochmann said:


> What's your .5 good for?



So, we are at 25.
5 to go? <-- my conjecture that the actual answer is 20... so 5 more depth eliminations to go  You are right, it's ambiguous.


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## Dene (Mar 27, 2008)

I didn't have any problems reading it^^



Johannes91 said:


> > ... it’s also known that there are no configurations that can be solved in 21 moves.
> 
> 
> ?



LMAO!!


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## Stefan (Mar 28, 2008)

Argh. See? That wouldn't be confusing if you had written it properly, i.e., writing "Five".

I highly recommend Donald Knuth's "Mathematical Writing":
http://tex.loria.fr/typographie/mathwriting.pdf

Page 1, rule 2: "Don't start a sentence with a symbol."


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## Rune (Mar 28, 2008)

> He’s shown that there are no configurations that can be solved in 26 moves



I am by no means an expert in English. Can anybody explain the logic here to me?


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## Stefan (Mar 28, 2008)

uweren2000 said:


> > He’s shown that there are no configurations that can be solved in 26 moves
> 
> 
> 
> I am by no means an expert in English. Can anybody explain the logic here to me?



There's none. The author is an idiot.


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## Dene (Mar 28, 2008)

uweren2000 said:


> > He’s shown that there are no configurations that can be solved in 26 moves
> 
> 
> 
> I am by no means an expert in English. Can anybody explain the logic here to me?



This can be interpreted in three different ways, one of them is accurate, the other two are plain stupid, which is what makes it funny.

We could rephrase this as either:
"It has been proven that no cube can be solved in _less than_ 27 moves."

"There are no cube configurations that can be solved in _exactly_ 26 moves" (lol)

Or the proper interpretation:

"There are no cube configurations that require _more than_ 25 moves to be solved"


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## badmephisto (Mar 28, 2008)

StefanPochmann said:


> Argh. See? That wouldn't be confusing if you had written it properly, i.e., writing "Five".
> 
> I highly recommend Donald Knuth's "Mathematical Writing":
> http://tex.loria.fr/typographie/mathwriting.pdf
> ...



everyone else seemed to get it


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## Lucas Garron (Mar 28, 2008)

badmephisto said:


> StefanPochmann said:
> 
> 
> > Argh. See? That wouldn't be confusing if you had written it properly, i.e., writing "Five".
> ...


They did?


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## Dene (Mar 28, 2008)

Yes they did


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## tim (Mar 28, 2008)

Dene said:


> Yes they did



Nope, they didn't


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## badmephisto (Mar 29, 2008)

tim said:


> Dene said:
> 
> 
> > Yes they did
> ...



maybe not right away of course, but i made it slightly cryptic on purpose. Most of the people should get it from the explanation in the first post though, especially after checking out the link and reading about what I am talking about  Extremely clear communication is boring.


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## Rune (Mar 29, 2008)

badmephisto said:


> tim said:
> 
> 
> > Dene said:
> ...





Dene said:


> uweren2000 said:
> 
> 
> > > He’s shown that there are no configurations that can be solved in 26 moves
> ...



To me the last sentence is a proper *statement*. A proper *interpretation* should be (to me): "There are no cube configurations that can be solved in _exactly_ 26 moves"


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## Johannes91 (Mar 29, 2008)

Dene said:


> > There are no configurations that can be solved in 26 moves
> 
> 
> Or the proper interpretation:
> ...


That's a correction or a rewrite or something, not an interpretation. The statement is plain wrong no matter how you look at it.

Or is the proper interpretation of _"1 equals 2"_ something like _"1 doesn't equal 2"_?

Edit: And now this article, linked from speedcubing.com, uses that very same sentence.


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## Rune (Mar 29, 2008)

The sentence here: 
"There are no configurations that can be solved in 26 moves" is copied from 
that very article.


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## Dene (Mar 29, 2008)

Well I don't see what the problem is. I can interpret that sentence in either of the three ways, despite the fact that the proper one isn't very obvious. The sentence literally could mean either of the three sentences I posted, it is just a matter of where you fill in the missing (implicit) information.


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## Lucas Garron (Mar 30, 2008)

Johannes91 said:


> Edit: And now this article, linked from speedcubing.com, uses that very same sentence.


That reminds me of my theory that dictionaries copy from each other. I've seen the speed of light listed as 299972458 m/s in at least two physical dictionaries.


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## Johannes91 (Mar 30, 2008)

Dene said:


> The sentence literally could mean either of the three sentences I posted


Ok, I guess you know better. But I just can't figure out how this:

_"There are no configurations that can be solved in 26 moves"_

could possibly have the same meaning as this:

_"There are no cube configurations that require more than 25 moves to be solved"._

Those two sentences seem contradictory to me. All configurations can be solved in 26 moves, the first one is just plain pointless.


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## ShadenSmith (Mar 30, 2008)

Lucas Garron said:


> Johannes91 said:
> 
> 
> > Edit: And now this article, linked from speedcubing.com, uses that very same sentence.
> ...



You'll find the acceleration due to gravity (g) = -9.81 m/s^2 in almost any physics textbook.


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## masterofthebass (Mar 30, 2008)

the acceleration doesn't have a - direction. Because your reference frame can be in any direction, most textbooks just give the magnitude .


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## Dene (Mar 30, 2008)

Johannes91 said:


> Dene said:
> 
> 
> > The sentence literally could mean either of the three sentences I posted
> ...



Maybe your English is just lacking. Although it isnt't clear, with the right implicit information put in there it can be interpreted that way.


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## Johannes91 (Mar 31, 2008)

Ok, maybe my English is lacking even more than I thought. Once more:

"There are no configurations that can be solved in 26 moves."
=> "All configurations can be solved in less than 26 moves."
=> "There are configurations that can be solved in 26 moves."

Do all native English speakers here agree that this really is correct? Seems a bit counter-intuitive to me. Is there a general rule for weird situations like this, where a sentence can apparently mean something completely different from what it says?


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## Dene (Mar 31, 2008)

It needs to be more like:

"There are no configurations that can be solved _with a need of_ 26 moves"


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## Swordsman Kirby (Mar 31, 2008)

"All configurations can be solved in less than 26 moves."

Now be quiet. 

By the way, the position generated by (RU)x13 can be solved in exactly 26 moves.


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## Johannes91 (Apr 1, 2008)

Dene said:


> It needs to be more like:


But, as far as I can tell, it isn't.



Swordsman Kirby said:


> By the way, the position generated by (RU)x13 can be solved in exactly 26 moves.


Show me a position that *can't* be solved in exactly 26 moves, and I'll be impressed.


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## pjk (Apr 1, 2008)

> "There are no configurations that can be solved in 26 moves."
> => "All configurations can be solved in less than 26 moves."
> => "There are configurations that can be solved in 26 moves."


All of those have a completely separate meaning. I think the middle one is the one you're trying to get at.


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