Message #996

From: Melinda Green <>
Subject: Re: [MC4D] Sub-100K for 3^7
Date: Mon, 12 Jul 2010 22:20:18 -0700


I opened your log file in MC7D and undid one move. I hit redo and undo
several times trying to understand how that last twist worked and I
completely failed. Maybe it would help if the twists were animated but
maybe not even then. Fooling with it I imagine that I feel much like one
of my friends must feel when I show them MC4D for the first time. I kind
of know what I’m looking at but it doesn’t make a lot of sense to me
yet. I think that I feel the same way about MC5D.

I’m definitely comfortable with all of the 4D puzzles and I have a good
sense about how the difficulty can go down as the number of faces goes
up but that’s different from the extra "room" that you get with each new
dimension which I have less of an intuitive feeling about. I also think
that it’s interesting that as the number of faces goes down that puzzles
get harder but only to a point. After that they seem to get easier
again. I think that we’ve wondered before about which puzzle has the
most difficulty for its size. I’m not sure whether there’s a good metric
for that concept but for me it is probably the original 3D Rubik’s cube,
or possibly the Skeweb <>. or other
small 3D puzzle.

I’m betting that a lot of members would like to hear more about your
latest conquest. I know that I’d like to hear as much about how you felt
during the experience than I would about your technical approach and
techniques. I’m interested in both aspects but I would especially like
to hear more about how this puzzle is different than lower-dimensional
ones. Like the concept of there being more freedom and how to use that
freedom. And more about your misplaced 6C cubies, that sort of thing.
You’re the only person so far to climb this peak and return alive so I’d
like to hear more about the trip up and the view from the top. Whatever
you care to describe.


Andrey wrote:
> Melinda, thank you!
> Somehow I’m sure that I’ll not try to solve 3^6 in the nearest future. Even if it’ll take 5 days, it’s too much for me now. And there are too much challenges ahead: 4^5, some 4D puzzles (like {3}x{3},4), maybe 120cell (but I’m not sure about it), implementation of 24cell and 5D simplex…
> Strange thing is that solving of 3^7 doesn’t mean that you can solve 3^4 or 3^3 :) If you reduce higher dimensonal puzzle to lower dimensional you restrict your set of operations and may meet parity or orientation problem. And if one is able to walk around it in 7D, e.g if he designs macros for transposition of two stickers of single cubie - and 3-cycle of stickers of corner, he still will not be able to use them in 3D :) And "14 of them" - do you include there 2^1? :D
> There is another kind of confusion - how to count 5D solutions of MC7D… In one sense they are same 5D puzzles, in another interface of MC7D is very different from MC5D.