The Mathematics of the Rubik’s Cube (2009) [pdf]

Re:The Mathematics of the Rubik’s Cube (2009) [pdf] by Someone on Monday February 11, 2019 @07:47PM (#19140006)

Depends on what you call a ‘rotation’. After 10k random 90 degree turns of a face, you have an even permutation on both corners and edges, which means you can’t reach half the positions.

That’s easily corrected (e.g: flip a coin first to determine whether to do 10k or 10k+1 random rotations), but this shows it is easy to make slip ups solving such a seemingly trivial problem.

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Re:The Mathematics of the Rubik’s Cube (2009) [pdf] by Retric on Tuesday February 12, 2019 @12:37AM (#19141315)

What you’re describing falls under rotational symmetry.

Rotating top side left one is the same as rotating bottom 2 sides right.

But, more generally limiting rotations to 90 degrees slows things down as 90 or 180 degree rotations can be directly computed with the same overhead.

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