Slashdot Mirror
A Working 5D Rubik's Cube
Melinda Green writes "Readers who enjoyed the previous
Slashdot postings regarding the 4-dimensional Rubik's cube called MagicCube4D will
be interested to know that a couple of brilliant developers have
recently created a working 5-dimensional Rubik's
cube. Operating a 5 dimensional puzzle projected all the way down
to a 2D computer screen may seem a hopeless task but the full 5D puzzle
has already been solved
by 3 people. Also noteworthy is the fact that the 4D puzzle has now
been ported to Java and is available as both a full-featured desktop
application and as an Applet."
n/t
You don't need to explain your reasons not to solve this puzzle.
Anyone know where you can buy a real 5D cube? I hate trying to solve them on a computer screen. Much easier in real life.
Also I will need a spare set of 4 dimensional stickers in case the original ones fall off.
I'll probably be modded down for this...
...peel off the stickers in 5 dimensions?
And the least time in which I could solve the cube was 20 minutes.
o n.html
Using a few simple, easy-to-learn algorithms, and with a few weeks practice it is possible for pretty much anyone to solve the 3D cube in just 2 or 3 minutes. Using a layer-by-layer method you can solve each piece one at a time in the first two layers, then learn 4 algorithms to fix the last layer (not necessarily in this order):
1) Rotate edges
2) Rotate corners
3) Permute corners
4) Permute edges
Sometimes you will have to use an algorithm twice. Each algorithm takes about 10 moves, and at a slow speed of one move per second and a bit of luck you can solve the last layer in under a minute. Here's a beginner's guide:
http://peter.stillhq.com/jasmine/rubikscubesoluti
If you want to get faster you need to learn more algorithms so that you can complete two steps at once.
A popular method which can be used to get very fast times is the Fridrich method, but it requires a lot of memorisation and lots and lots of practice:
http://www.ws.binghamton.edu/fridrich/cube.html
Personally I managed to get times of under 1 minute by practising the cube every day in the bus to and from work.
I'll probably be modded down for this...
it requires .NET. Thanks. I don't mind downloading and installing
30MB's of framework just to play with a Rubik's cube. Really, I don't.
.NET developer who
does not), since Visual Studio 2005 builds to .NET 2.0, just about
everything will use it within a year or two. Add to that Vista's
intended use of WinFX (basically just .NET 3) as the core API, and you
can pretty much kiss Win32 goodbye.
.NET has truly abysmal performance. Who cares
about the size on disk - I care far more that it eats memory like
a kid with a box of tic-tacs. (Cue someone parroting that you can get 4GB
for about $250 nowadays, which I think you'll agree completely misses the
point).
.NET; Sooner
or later you will have no choice, so why deprive yourself of
cool toys that (unfortunately) use it now?
I see you've gotten spanked as a troll... Unfortunate. Personally, I don't suspect you of trolling, just stating a fact. However...
Whether you like it or not (and I say this as a
A pity, really, because
Regardless, you would do yourself a favor to get used to
But you can get 4GB for about $250 nowadays! Stop complaining!
Join the anonymous, help develop the network: http://www.i2p2.de
And that's in flash... with an iPod Nano surrounding it!
You know, the Nazis had pieces of framework that they made the Jews download.
Oh my god, you're right! It does look like he wrote this application in .NET solely for the purpose of being a huge burden on everyone! After thinking about it, I guess it really does have nothing to do with .NET probably being the language he's most familiar with. I'm sure that he probably did want to spend several months learning a new language for something that could best be described as an amusing diversion, but chose not to because he wanted to waste the few minutes it would take you to download and install .NET. Come to think of it, I'm sure the fact that most people already have .NET installed probably just makes him mad, because it mitigates the toll his application will take on society.
The fact that it's kind of cool is only a ruse in his more diabolical agenda of making your life miserable for five or so minutes. The fact that we are compelled to install it by means I don't quite understand yet only makes the situation worse. If only we had a choice whether or not we wanted to play with a 5-dimensional Rubik's Cube!
Personally, I think that if you're as outraged as I am, since you're obviously so much smarter then me, you should rewrite his application in a morally superior language. The kink in this fool's plan is that he seems to have forgotten to patent the application (but be careful, it could be another trick!), which leaves the door open for anyone to simply rewrite it!
Please start working on it right away, as this outrage must not go unanswered!
It's a true 4 dimensional puzzle in the sense that this is what you could build as a rubik's cube equivalent if we lived in a 4d universe rather than a 3d universe.
... the 'rear' of the cube if you will.
The green cubes that appear and disappear as you make moves are from the 'hidden' face of the hypercube, which has 8 faces. Their projection is using a base unfolding, to understand what they've done consider the parallel from unfolding a 3d cube into 2d. Imagine you are staring precisely face on at a cube:
XXX
XXX
XXX
Now unfold all the sides connected to the X's so you can see them straight on:
OOO
OOO
OOO
AAAXXXBBB
AAAXXXBBB
AAAXXXBBB
MMM
MMM
MMM
If you started playing a game of rubik's cube on this, you'd soon see another letter show up whenever you made a move, let's call it G for green. Where do the G's come from? From the sixth face of the cube that wasn't visible due to the choice of unfolding. The face exactly opposite of the X's
Same thing in the 4d case. There are 8 faces, only 7 of which are visible due to their poor choice of unfolding technique.
Here's wolfram's hypercube page for more info:
http://mathworld.wolfram.com/Hypercube.html
"Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
Although time is said to be the 4th dimension is time, it is only an analogy. Time appears in several physical equations in a context similar to the 3 spatial dimensions, but it is always treated differently.
For example, the spacetime "distance" is calculated by:
sqrt(x^2+y^2+z^2-c^2*t^2)
Notice the negative sign and the additional speed-of-light factor.
If there were 4 spatial dimensions, the distance would be calculated by
sqrt(x^2+y^2+z^2 + v^2)
taking v as the displacement in the 4th dimension.
The Rubik's cube programs work by projecting 4 or 5 dimensions onto a 2 dimensional plane (your screen), basically in the same way that perspective is used to project 3D pictures onto 2D planes.
So the 4th and 5th dimension aren't mathematically or conceptually different to the familiar 3 dimensions. The only difference is that we cannot comprehend them.
Here you go:
http://ptth.net/slashdot/2d_rubik's_cube.JPG
"Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking