Message #3916

From: Ty Jones <whotyjones@gmail.com>
Subject: Re: [MC4D] Physical 2x2x2x2 - Canonical moves
Date: Thu, 04 Jan 2018 23:31:18 +0000

Oops! Looks like the link has an extra period in it 🙂
https://www.youtube.com/watch?v=fYxn4wPe2ZE 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 melinda@superliminal.com
[4D_Cubing] <4D_Cubing@yahoogroups.com> wrote:

>
>
> First off, please check out Zander Bolgar’s lovely solution video
> <https://www.youtube..com/watch?v=fYxn4wPe2ZE> 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
> <https://groups.yahoo.com/neo/groups/4D_Cubing/conversations/topics/3803>
> and Joel’s
> <https://groups.yahoo.com/neo/groups/4D_Cubing/conversations/messages/3904>
> solutions as well as Marc’s <https://www.youtube.com/watch?v=pKHU5sFaGvY>
> 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
>
>