Message #599

From: Chris Locke <>
Subject: Salutations!
Date: Tue, 09 Dec 2008 16:28:42 +0900

Hello everyone! First of all, I’d like to thank Melinda for inviting me to
this mailing list!

My name is Chris Locke, and I recently solved the 3^4, 4^4, and 5^4
puzzles. Roice’s solution guide was indispensable for getting started.
After solving the 3^4 using Roice’s guide (although I had to use my own
notation for moves), I was familiar enough with the Magic Cube 4D interface
to move on to the higher order puzzles. Macros were critical, as I don’t
think I would’ve had the patience to go through the algorithms by hand every
time. The 4^4 cube presented a new challenge, as I had no guide to start
with. So the first thing I did was try out the algorithms I already knew
for the 3D case. It turned out, that by using conjugation and/or
commutators, I was able to build new algorithms to accomplish the tasks I
wanted. For instance, I had one algorithm that would swap two pairs of face
pieces. I would then take that algorithm, then after applying it move one
of the affected edges such that it would flip its orientation, then undo the
original algorithm to get an new algorithm for building edge pieces. As for
parity, the 3D algorithms were sufficient I found for solving face parity
situations, but I didn’t know how to deal with edge parity cases. Luckily,
I never ran into edge parity problems! Once I moved to the 5^4 cube, I
realized that for moving center and face pieces around, I couldn’t just use
the 4^4 algorithms, as they weren’t general enough. However, I had never
solved a 3D 5^3 cube yet, so I had to look up some 3D algorithms. Then,
using the same ideas as before, I was able to discover ways of doing
3-cycles to center and face pieces. Although if I remember correctly, it
wasn’t just one commutator any more; I think one of the moves ended up being
a quadruple nested commutator (of the form [[[[a,b],c],d],e]), although the
original 3D move was already a double commutator. Took a bit of work to
find moves that actually did what I wanted to, but eventually I succeeded.
Although I didn’t macro the full algorithm, as inputting a 46 move algorithm
was a little bit much… so instead I macroed the 22 move triple commutator,
then simply did the middle move and inverse by hand :D. As for building
edges, I was able to just use my 4^4 move to accomplish this task. I found
that the biggest difficult with these larger cubes was patience… patience
to find the right pieces and being able to find out exactly where you want
them to go. There’s a lot going on after all. Oh yeah, and I don’t think
you’ll be seeing me attempt the 5D cube any time soon… the main reason I
was able to cope with the 4D cube was because of the friendly interface.
Being able to navigate in 3D really helped me in solving it. But when I
look at the 5D cube, it is just a scary mess! And it seems difficult to
input moves based entirely and chosing which axis and whatnot. I wouldn’t
be surprised if I tried sometime though, just not soon :). Oh yeah, and
that Magic Cell 120 thing is a monster… although the one redeeming feature
of it is that it is so large, it’s practically 3D!

As for myself, I finished my undergrad this summer, majoring in physics and
mathematics. This fall, I moved to Tokyo, where I’m working at a
university, on scholarship as a research student. That basically means I do
research, but don’t have to do any of the other things that grad students do
:D. After this research term is over, I will enter grad school, although in
exactly what disipline I haven’t yet decided. Obviously, something
physics/math related though. It will probably involve programming too
(although most research does now anyway), as I have lots of experience now
in that field. My favorite past-time would have to be ice hockey. I still
closely follow the Vancouver Canucks from Tokyo, and also am playing ice
hockey here on a weekly basis. Outside of hockey, I like music, watching
TV, playing some video games, and just hanging out with friends. I only
started solving cubes and whatnot this summer. Although I hate memorizing
algorithms and don’t want to "practice" it, so I’m not very fast at all!

Well, that’s about it!

Chris Locke