Message #3917

From: Joel Karlsson <>
Subject: Re: [MC4D] Physical 2x2x2x2 - Canonical moves
Date: Fri, 05 Jan 2018 08:01:46 +0100

Regarding #9: to get solvable states the number of single cap twists has to
be even (a single cap twist is an odd permutation but only even
permutations are possible for the 2^4). I don’t think that a single cap
twist breaks the corner rotation restriction so as long as an even number
is used everything should be fine.

Best regards,

Den 5 jan. 2018 12:33 fm skrev "Ty Jones [4D_Cubing]" <>:

Oops! Looks like the link has an extra period in it 🙂 there’s the corrected one for
anyone too lazy

Looking forward to watching the video!

On Thu, Jan 4, 2018, 4:28 PM Melinda Green
[4D_Cubing] <> wrote:

> First off, please check out Zander Bolgar’s lovely solution video
> <> that he invited me to
> share. It’s very cool to see someone developing something like finger
> tricks and blasting through a solution. It’s very much like Bob’s
> <>
> and Joel’s
> <>
> solutions as well as Marc’s <>
> approach.
> This makes for a great launching point for questions about which moves
> should be included in a canonical set. Of course any move that results in a
> reachable state can be justified in a solution, but there’s such a spectrum
> from "obviously fine" to "obviously not". Now that we’ve gotten some
> experience with this puzzle and the practicalities of solving it, I feel
> it’s time to see if we can find some sort of natural canonical set, so I’d
> love to hear your thoughts.
> Here is the list of moves I know about, loosely ordered as described above:
> 1. Simple rotations
> 2. 90 degree twists of outer face
> 3. 180 degree twists of side face
> 4. Center face axial twist
> 5. Arbitrary half-puzzle juxtapositions
> 6. Clamshell move
> 7. Whole-puzzle reorientations
> 8. 90 degree twist of side face (each 2x2x1 square rotate in opposite
> directions)
> 9. Single end cap twist (with parity restrictions?) [fine for
> scrambling]
> 10. Restacking moves [fine for scrambling]
> 11. Single piece flip
> 12. Reassemble entire puzzle
> I suspect the trickiest part has to do with #9 which is the one I would
> most like to nail down.
> I intend to create a follow-up video to talk about all of these and any
> others you can think of. The way you can help is to offer additions and
> corrections to the above list, and especially in suggesting ways to reorder
> it. Then please suggest where you’d draw three lines:
> - Everything above is primitive (Or "basic" or "elementary" as Joel
> calls them)
> - Everything above is canonical. IE always acceptable in solutions
> - Nothing below is acceptable in solutions.
> Thanks all!
> -Melinda