Talk:Optimal solutions for Rubik's Cube
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I changed the link from mathematical constructivism to constructive proof because, although IANAM, I feel the notion of constructive vs. non-constructive proofs does not depend on the philosophy of constructivism, and the latter is not really relevant to the topic at hand. Unfortunately I don't think I'm up to actually writing the article on constructive proofs... :(
Oh goody, Gandalf61 just did :)
24 quarter turns changed to 26 quarter turns by anonymous editor, can anyone cofirm? Κσυπ Cyp 22:51, 20 Jan 2004 (UTC)
I can confirm it. On the following page http://www.math.ucf.edu/~reid/Rubik/x_symmetric.html there is a positions that needs 26 quarter turns. Here is the solution
U2 D2 L F2 U' D R2 B U' D' R L F2 R U D' R' L U F' B'
User:Sander123 3 febuary 2004.
Hmm. In this article http://www.americanscientist.org/template/BookReviewTypeDetail/assetid/25829;jsessionid=baa4XNTR6LdtGz it is claimed that there are also positions that need 21 face turns. I haven't found one yet though. User:Sander123 3 febuary 2004.
A position with 21 face turns has not been discovered up to now. User:Herbert Kociemba 9 febuary 2004.
The mathematics concerning Thistlethwaites and my algorithm was not correct. The subgroups there definitely are not normal and so the coset spaces are no groups! I changed it. User:Herbert Kociemba
The article Rubik's Cube says that "all cubes can be solved in 23 moves or fewer." Is this correct? Does it need to updated changed? Is this perhaps the correct number? (The Swami 05:54, 11 November 2005 (UTC))
According to the 6 Step Solution Guide that is included in all recent Rubik's Cubes sold today, all cubes can be solved in 20 twists or less. "RUBIK Fact: Most cubes can be solved in only 17 moves with the aid of a computer, and theoretically there is no cube that requires more than 20 twists to solve. Some people can solve the cube in under 45 moves from any scrambled positon; and a few can even solve the cube blindfolded!" This may prove to be a valuable addition to the article.User:Ring-Ding July 29, 2006.
Though 20 twist is suspected to be the actual lower bound, this has not been proven, afaik. Sander123 11:52, 31 July 2006 (UTC)
[edit] "How to solve the Rubik's Cube" Link
How to solve the Rubik's Cube is no longer a valid link. Was that article deleted, or moved, or merged? This article seems to build off of that old one, so if it was deleted, at least a little information of it should be merged into this one. If it was moved, the link should be changed too. Fieari 06:51, July 23, 2005 (UTC)
It got moved to wikibooks:How to solve the Rubik's Cube -- Spoon! 05:19, 8 August 2005 (UTC)
[edit] Dedmore?
Why does no one speak of the excellent solution by Denny Dedmore? I have learned it this way, and it is much easier as a beginner's soulution, but can be executed quite quickly. Plus, it is highly visual and easy to understand, utilizing move sequences for the posistion of cubies on the cube face.Fishdert 22:46, 25 February 2007 (UTC)Fishdert —The preceding unsigned comment was added by Fishdert (talk • contribs) 22:45, 25 February 2007 (UTC).
- Because this page is about solution that are optimal. I don't know dedmore's method but very likely it can't solve a cube in worst case 27 turns. The solutions on this page are not intended to be used by humans for solving cubes in practice. Bye. Sander123 15:32, 26 February 2007 (UTC)
