Hello all, let me introduce myself to this select group.
I'm Chris Watson, 32 years old. Originally I was a physicist but I've
mutated into an engineer over time. I come from the UK, but I now
work in Germany, doing spacecraft operations. (This prob. sounds
quite exciting, but the reality is mainly lots of integration and
system testing prior to the real thing happening. It has it's moments
though, e.g. simulations - these can get (just a little bit) like
the simulation bit at the beginning of Wrath of Khan. Currently I'm
working on MSG2, a GEO meteosat that will go up early next year, and
Herschel-Planck, two astronomy sats going to Lagrange point L2 a few
years hence. These days some of what I do is dangerously close to
management :-( , but I prefer to think of it as some of the
things that I now integration test happen to be people.)
Outside of work I like books (e.g. Snowcrash, Strange Case of the Dog
in the Night Time), film (e.g. Cypher), martial arts and outdoorsy
stuff like climbing. I enjoyed leading a youthgroup whilst in the UK,
but my frankly rubbish German language skills have put this activity
on hold for now.
Anyway...
Magic cube-wise my solution wasn't very clean (it's uploaded if
anyone wants to see it in all it's messiness), since there was an
awful lot of me moving faces back and forth to get a feel for what I
was doing. My approach was to try to do it essentially the way I do
the normal cube, but obviously generalised up for the extra
dimension - complete one cube and then build outwards, through
the "middle layer" and on to the final still-muddled cube. In general
I tried to do all the "mixing moves" on (...sometime adjacent to) the
last cube to be solved. This final cube I did with adapted "final
face" moves from the 3d cube. I did the normal 3d algorithm one way,
rotated the inner unsolved cube, and then undid the 3d algorithm to
restrict all changes to the inner cube. This gives a set of
algorithms for moving a few hyper-cubies restricted to a single face.
This is an easy approach for someone like me thinking mainly in terms
of the 3d cube manipulations, but can't have been particularly
efficient. I should really have a go at cleaning the approach up
some...
Embarrassingly, having to unscramble the face centres mid way through
came as a surprise, because of course you don't have to worry about
this on the normal cube.
It took me back twenty years to when I was first playing with the
original cube. Thinking "...now if I just rotate this bit here... no
wait, that disturbs this part over here.." etc. Absolutely fantastic.
Thanks to Don, Melinda and Jay for putting the splendid thing
together.
Chris.
Hi Chris,
> It took me back twenty years to when I was first playing with the
> original cube. Thinking "...now if I just rotate this bit here... no
> wait, that disturbs this part over here.." etc. Absolutely fantastic.
Yes, I think that was the most pleasant surprise of this project for me--
it transports you back to a previous time,
and yet this new context is bigger and richer, too
(as is your brain!)
Congratulations on solving it,
and thanks for sharing your experience!
Don
--
Don Hatch
hatch@plunk.org
http://www.plunk.org/~hatch/
Hey Chris,
Congrats on the cube! And much thanks for the intro. It was really
interesting to read about your profession, which sounds very cool. I'm
amazed that accomplishing things like sending satellites to orbit Lagrange
points is even possible.
Not that you would want take your work into the hobby realm, but I thought I
would pass along a registration code for a shareware simulator I have online
called Gravitation3D (http://www.gravitation3d.com). You can just cut and
paste this registration information into the program if you are interested
in taking a look.
email address: youarenotmorgansullivan@yahoo.co.uk
registration key: LFL6-DBLX-7ZFZ-6JHG
The calculation engine uses a simple integration scheme and so is not very
accurate, but I may be upgrading it some relatively soon in response to a
request from a company doing some work for NASA. Because of their interest,
just earlier this week I was learning about Lagrange points and attempting
to create some stable L4 and L5 Lagrange point orbits with it. So reading
your intro was a cool coincidence.
Anyway, congratulations again on the cube :)
All the best,
Roice
> -----Original Message-----
> From: youarenotmorgansullivan
> [mailto:youarenotmorgansullivan@yahoo.co.uk]
> Sent: Sunday, June 13, 2004 1:39 PM
> To: 4D_Cubing@yahoogroups.com
> Subject: [MC4D] new member
>
>
> Hello all, let me introduce myself to this select group.
>
> I'm Chris Watson, 32 years old. Originally I was a physicist but I've
> mutated into an engineer over time. I come from the UK, but I now
> work in Germany, doing spacecraft operations. (This prob. sounds
> quite exciting, but the reality is mainly lots of integration and
> system testing prior to the real thing happening. It has it's moments
> though, e.g. simulations - these can get (just a little bit) like
> the simulation bit at the beginning of Wrath of Khan. Currently I'm
> working on MSG2, a GEO meteosat that will go up early next year, and
> Herschel-Planck, two astronomy sats going to Lagrange point L2 a few
> years hence. These days some of what I do is dangerously close to
> management :-( , but I prefer to think of it as some of the
> things that I now integration test happen to be people.)
>
> Outside of work I like books (e.g. Snowcrash, Strange Case of the Dog
> in the Night Time), film (e.g. Cypher), martial arts and outdoorsy
> stuff like climbing. I enjoyed leading a youthgroup whilst in the UK,
> but my frankly rubbish German language skills have put this activity
> on hold for now.
>
> Anyway...
> Magic cube-wise my solution wasn't very clean (it's uploaded if
> anyone wants to see it in all it's messiness), since there was an
> awful lot of me moving faces back and forth to get a feel for what I
> was doing. My approach was to try to do it essentially the way I do
> the normal cube, but obviously generalised up for the extra
> dimension - complete one cube and then build outwards, through
> the "middle layer" and on to the final still-muddled cube. In general
> I tried to do all the "mixing moves" on (...sometime adjacent to) the
> last cube to be solved. This final cube I did with adapted "final
> face" moves from the 3d cube. I did the normal 3d algorithm one way,
> rotated the inner unsolved cube, and then undid the 3d algorithm to
> restrict all changes to the inner cube. This gives a set of
> algorithms for moving a few hyper-cubies restricted to a single face.
> This is an easy approach for someone like me thinking mainly in terms
> of the 3d cube manipulations, but can't have been particularly
> efficient. I should really have a go at cleaning the approach up
> some...
>
> Embarrassingly, having to unscramble the face centres mid way through
> came as a surprise, because of course you don't have to worry about
> this on the normal cube.
>
> It took me back twenty years to when I was first playing with the
> original cube. Thinking "...now if I just rotate this bit here... no
> wait, that disturbs this part over here.." etc. Absolutely fantastic.
> Thanks to Don, Melinda and Jay for putting the splendid thing
> together.
>
> Chris.
>
>
>
>
>
>
> Yahoo! Groups Links
>
>
>
>
>
>
>
Hi Sebastian and all...:)
How are you?
It is great to see someone so excited...(whispering: It is you,
Sebastian)...
Sebastian wrote:
>The method I used is basically the same as for the 3x3x3 cube. I can detail
>it if you want me to.
So, I would like to know, which algorithm for the 3d-cube did you expand for
solving the 4d-cube?
Please, describe more specifically your ideas with regard to the expansion.
don't spare with mathematical details, if there are any.
bye for now,
Liati.
_________________________________________________________________
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> So, I would like to know, which algorithm for the 3d-cube did you
expand for
> solving the 4d-cube?
First of all, the method. I used the Petrus method which you can
find here: http://lar5.com. The idea of this method is the
construction of blocks of pieces that do not obstruct moving other
faces, so that more and more of the cube gets solved. When only one
face is left to be solved I apply algs which I know beforehand and
which I know how they will affect the cube. The algs I used for the
3x3x3x3 are the ones called Sune and Niklas in the Petrus method.
I used the Sune to permute centres and edges, and the Niklas to
permute the corners. There are two ways of executing an algorithm.
The first way, that which I used for permuting the centres, is
simply pretending that two adjacent faces are two-dimensional, and
the effect of the algorithm is that groups of 3 pieces in 4
dimensions correspond to one piece in three dimensions, that is one
centre piece and two edge pieces that touch that centre piece and
are opposite to each other correspon to an edge piece in three
dimensions, and a column of one edge piece and two corners
corresponds to a corner in three dimensions.
When I used this kind of algorithm, I only cared about permuting the
centres. The second way of doing it, the effect of which looks
exactly like the algorithm done in three dimensions, was used for
the edges. The idea is to pretend we only have to solve the last
face of a three-dimensional cube. We will simulate turning two 3x3
faces of the same 3x3x3 face of the 4D cube. We will turn one of
them by turning a 3x3x3 face (let this face be B) adjacent to the
3x3x3 face in question (let this face be A). Next, we move face A so
that the 3x3 face that we want to move next is oriented towards face
B. Then we move face B. And so on. Only faces A and B will be moved,
and so we can simulate any sequence on moves on the 3x3x3 cube. If
such an alg is done, the centres are not moved at all, and the
colour of all pieces that are in face A that is at the beginning in
face A stays in face A.
This just gave me an idea of a method:
1. Solve everything but one face of the cube
2. Orient all pieces of that face (let it be face A) so that their
stickers that belong to face A are in the face A
3. Solve that face like a 3x3x3 cube.
I'm going to try this right now.
Sebastian
Hi
My name is Tomaz Tomaszewski. I'm 16 years old (young :D). I'm form
Poland, Czaplinek. I like cubing, especially speedcubing. When I saw a
4D cube I thought I'll never solve it :)
I really enjoy belonging this group. I solved a 4D cube a couple days
ago. My first 3x3x3 solve was in march this year. I like math, but in
my school there is nobody (teachers too) who really knows well.
I don't know what more I should wrote, so this is the end of my story :)
P.S. sorry for my english