Message #2073

From: Melinda Green <>
Subject: Re: [MC4D] MagicTile, Topology of MT IRP {5,5} 8c F 0:0:0.85
Date: Tue, 24 Apr 2012 11:46:16 -0700

Hello Eduard,

I tried your macro a13
and it is interesting. I’ve not used the macros in TM before so I’m not
sure how they are supposed to be used but when I click on a red face
near the vertex adjacent to the white and blue face it indeed exchanges
two edges but click it elsewhere makes a mess. This was done in the
hyperbolic view (Show as Skew = false) because in IRP mode I get an
error saying that macros are not available in IRP mode. It does seem to
work anyway, so maybe it is fine for this model though I’m not certain
that the behavior is the same as in the hyperbolic view. Regardless,
this is certainly an excellent macro and probably all one would need to
solve this odd, unlikely and lovely little puzzle.

Strange as it may be, I am fairly certain that it is still an orientable
surface. It has genus 3 which is common. I don’t know if there is
anything odd about its topology and would be interested to learn
anything more about it that people may discover.


On 4/24/2012 4:51 AM, Eduard wrote:
> This puzzle is not trivial. I wanted to have a sequence (macro) which flipps to neighbouring edges. A little by luck I found such a sequence which got the name a13. Doing a walk which brings back an edge in flipped state takes a lot of place and it is not easy to find a 3-cycle in the complement. Applying this macro is not easy in this puzzle. Having the reference point inbetween the two flipped edges I had to try all 5 positions in the face to find the only one which works (in wrong positions there was no effect or completely other effects than a double flip). With a setup it was always possible to get arround this problem.
> I think the problem is typical for the topology of this puzzle. Can anybody of you do a more profound analysis? Is this puzzle 1-sided? Is it orientable? We have only 8 colors what forces a non trivial "glueing" of edges (oriented edges?).
> I uplaod my macrofile for this puzzle on the 4D cubing group. Try the macro a13.\