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See 4-D Space With 3-D Glasses

purpleant writes: "A hyperplane is a 3-dimensional space that slices through the 4-dimensional space, the same way a 2-dimensional plane can slice through our 3-dimensional space. The bounding hyperplanes can be extended infinitely so that they criss-cross through each other, chopping up hyperspace into many 4-dimensional 'chunks.' Again the inner chunks are finite, and they are distributed in shells around the core polytope. The HyperStar applet displays those finite chunks, one shell at a time. The inner shells are complete -- each shell completely encases the previous shell. The outermost shells have holes in them."

214 comments

  1. I don't understand by Anonymous Coward · · Score: 0

    4 dimensional space is relevant to slashdot, why?

    1. Re:I don't understand by utdpenguin · · Score: 0
      4 dimensional space is relevant to slashdot, why?

      Gee. I can't Imagine what 4-dimensional space, you now, physics and math and crap, would have to do with "news for nerds." Its not liek nerds migt be interestedis it, do you suppose?

      --
      In Soviet Russia you dant have to put up with these crappy jokes
    2. Re:I don't understand by Anonymous Coward · · Score: 0

      ...and it's not like you're a dyslexic retard, is it?

    3. Re:I don't understand by cioxx · · Score: 1

      Because It will take us closer to understanding or at least experiencing a dimension beyond 3rd, even if simulated.

    4. Re:I don't understand by DemonicAngel · · Score: 1

      Humans place too much value in understanding. Soon, you'll realize you don't understand half of what you think you do.

      --
      Nitwit! Blubber! Oddment! Tweak!
    5. Re:I don't understand by shftleft · · Score: 1

      All geeks should know about hyperspace! :) To learn more read some Michio Kaku... He really explains hyperspace to non-astrophysicists well.

      Here are some of his works.

      --
      People who have witty things here blow.
    6. Re:I don't understand by acasto · · Score: 1

      Beyond Einstein is an excellent read, highly recommended.

    7. Re:I don't understand by Anonymous Coward · · Score: 0

      Look out for the trolls, they bite. Well, they are not REAL trolls, but there's not really a better word.

    8. Re:I don't understand by airrage · · Score: 0

      That's a load of crap. My dad used to make cool pictures using his old mainframe terminal in the 70's. All those terms in the applet are made up: why not call ISOTOPYL 'MAKE COLORS CHANGE' instead.

      Yeah, this crap get's on slashdot...makes you wonder who you have to know to get submitted.

      "My father would make outrageous claims like he invented the question mark."

      --
      "This isn't a study in computer science, its a study in human behavior"
  2. 4 Dimensions by Anonymous Coward · · Score: 0, Funny

    In my complex analysis class at University, my professor said it was easy to visualize 4 dimensional functions. He proceeded to draw some kind of squiggle on the chalkboard and said, "There, just don't be close minded". We didn't laugh.

    1. Re:4 Dimensions by Anonymous Coward · · Score: 0

      Of course it's easy, just don't try to do it all at once. I start every day with visualizing a special case of a 4-dim object. In fact I'm doing that right now.

    2. Re:4 Dimensions by Izanagi · · Score: 1

      What, I only just found the 3rd dimension, now your telling me there are more!!!

      --
      SCO (noun.)- A Slimy Corporate Ogre. Often seeks free money.
  3. This looks vaugely familair by utdpenguin · · Score: 0, Funny
    Oh my God!!

    It the worlds first java-based kaladioscope!!

    Now all I need s a webbrowser at the end of a tube and I can relive my childhood.

    --
    In Soviet Russia you dant have to put up with these crappy jokes
  4. 4d space? by Anonymous Coward · · Score: 0

    I thought the fourth dimension was time.....

    1. Re:4d space? by Anonymous Coward · · Score: 0

      The fourth dimension is whatever you want it to be. Mostly it's just about stuffing another number into a vector. If that means time to you, so be it.

    2. Re:4d space? by Anonymous Coward · · Score: 0
      is whatever you want it to be.

      But what is the secret ingredient?

    3. Re:4d space? by Angry+White+Guy · · Score: 1

      But are there quantifiable planes which mimic the mathematical proof? I mean in 1D space, it's a dot. In 2D space it's a parabola, in 3D space it's a satellite dish. In 4D space is it a moving satellite dish? Does this hold true for higher functions as well?
      Or am I just talking out of my ass here?

      --
      You think that I'm crazy, you should see this guy!
    4. Re:4d space? by tgibbs · · Score: 2

      There is no natural numbering of dimensions, so time doesn't have to be the 4th. While time can be treated as a dimension, it's easier to think about additional spacial dimensions. Some current models in theoretical physics have a bunch of extra spacial dimensions in addition to time.

  5. Holy crap! by eatenn · · Score: 0, Troll
    My God...

    Think of the PORN!

    --
    "But the cars are all flashing me, bright lights are passing me, I feel life passing me by" - Stiff Little Fingers
    1. Re:Holy crap! by NanoGator · · Score: 3, Funny

      You realize, though, that real life girls are 4-dimensional. 5 if you count their emotional state.

      --
      "Derp de derp."
  6. Purdy... by blackcoot · · Score: 0, Offtopic

    ... too bad I don't really have a clue what it means. *sigh* I guess this is why I'm not majoring in Math ;-)

    1. Re:Purdy... by AaronBaker2000 · · Score: 3, Interesting

      ... too bad I don't really have a clue what it means. *sigh* I guess this is why I'm not majoring in Math ;-)


      You should read Flatland. It's a fun beginners guide to other deminsions. It's a great story too.

    2. Re:Purdy... by Anonymous Coward · · Score: 0



      int space[10][10][10][10]; or new Array(10, 10, 10, 10);

      has 4 dimensions

      [1][1][2][2] is a point in my 4d space array

      [2][2][1][1] is another point

      a plane (infinatly thin and infinately wide perfectly flat sheet) passing through both points is a 4 dimensional hyperplane.

    3. Re:Purdy... by ComaVN · · Score: 1

      uh no, you need 3 points to define a plane in 3d, and 4 to define a hyperplane in 4d. A hyperplane is 3d infinite "block". These pictures represent the intersections of such hyperplanes with certain 4d shapes.

      --
      Be wary of any facts that confirm your opinion.
    4. Re:Purdy... by Anonymous Coward · · Score: 0
      "beginners guide to other deminsions"

      is that like "amateur mars lander"?

    5. Re:Purdy... by Varitek · · Score: 1

      I agree, Flatland is great.

      Another tale to read is The Parable of the Cave, from Plato's Republic. This describes a person held from birth in a cave, behind a sheet of fabric, unable to move his head. All he has ever seen are shadows on the sheet from the fire in the cave - a 3d man in a 2d world.

      I did my third year project in hypergraphics. It took me a good 3 months to get beyond an inability to even conceptualise more than 3d. Reading Flatland helped, but I think the epiphany was when I came up with a word to add on to 'height, width, depth' - I decided to call the 4th 'outward'. That, and the mary jane, anyway.

    6. Re:Purdy... by tps12 · · Score: 1

      A great story? I thought Flatland was pretty cool from an historical standpoint, and it had some good stuff about visualizing higher-order geometry, but the story was pretty weak. IIRC, it was about a square who got squashed by a sphere and poked by some triangles. Not exactly edge-of-your-seat material.

      --

      Karma: Good (despite my invention of the Karma: sig)
    7. Re:Purdy... by dewhite · · Score: 1

      He (everyone with an interest) should read Michio Kaku's 'hyperspace' it covers most of the subject matter of flatland, and goes into more depth on the possibilities of higher dimensional space, and unified field theory.

      --
      -dewhite
    8. Re:Purdy... by _14k4 · · Score: 1

      Please, mod this up. Hyperspace is a Great book, that I have read many times. It's made the permanent collection above my toilet. Where all the good reading is done!

  7. cross eyed. by jericho4.0 · · Score: 1

    As if trying to visualize the 4th dimension wasn't enough to give you a headache it comes with a 'cross-eyed' setting.

    --
    "A language that doesn't affect the way you think about programming, is not worth knowing" - Alan Perlis
    1. Re:cross eyed. by Anonymous Coward · · Score: 0

      Yup, cross-eyes really stings. Choose 'parallel' everybody!

      z
    2. Re:cross eyed. by Anonymous Coward · · Score: 0

      I agree. Thinking too hard about a hypercube can make your head feel like it's about to explode. Damn that stupid Hypercube xlock screensaver.

  8. Reminds me of a story... by Overcoat · · Score: 2, Funny
    All this talk about envisioning 4-d space reminds me of an interview Forced Exposure did many years ago with SF writer/mathematician Rudy Rucker, who has written extensively about dimensional spaces beyond the third, both in fiction and nonfiction. I couldn't find the interview online anywhere, but the exchange went something like:

    FE:So, what's the closest you ever came to experiencing the fourth dimension?

    Rucker: Well, there was this one time, we'd been partying all night, and I wanted to get a little higher. We were almost out of drugs, but I did have some acid. So I took it, but then I fell asleep. And when I woke up...

    FE: Oh, I've been there. That's the fourth dimension?

    1. Re:Reminds me of a story... by Soulslayer · · Score: 2

      If youw ant to read an interesting description of "seeing" in a 5 dimensional plane (4 dimensions of space and 1 of time) checkout the excellent novel by Greg Egan called Diaspora.

      While the narrative occasionally grinds to a halt for lectures on advanced mathmatics and quantum physics it is a very enjoyable "hard science fiction" read.

      Greg Egan, Brian Stableford, Greg Bear and Robert Charles Wilson are my personal picks for the best hard science fiction writers out there today.

      And for you movie fans that wanted to know what James Cameron's "Avatar" was going to be like, BIOS by Robert Charles Wilson contains a large number of very similar elements.

      --


      Once more unto the breach dear friends...
    2. Re:Reminds me of a story... by Anonymous Coward · · Score: 0

      There aren't 4 dimensions of space.
      There are 3 dimensions of space.
      Height, Width, Depth.
      There is one 4th dimension.
      That being TIME.
      So im not exactly sure what the fuck u are talkin about.

    3. Re:Reminds me of a story... by invid · · Score: 3, Interesting

      According to the Theory of Relativity, mass curves space. The question is, in what direction is it curved? In the direction of a higher physical, non-time producing dimension, perhaps? You've seen all those pictures that show a representation of a black hole curving a two-dimensional space to a singularity. You've heard the theories about wormholes providing short-cuts through the universe. These theories take it for granted that our space is curved within a higher physical dimension. Instead of being the 4th dimension, time could be the 5th dimension.

      --
      The Moore-Murphy Law: The number of things that will go wrong will double every 2 years.
    4. Re:Reminds me of a story... by kasperd · · Score: 2, Insightful

      Instead of being the 4th dimension, time could be the 5th dimension.

      For some of that, there doesn't have to be more than 4 dimensions. The curving of space could happen in the time dimension, this just would require the curving only to change continuously over time, which seems quite reasonable. It might put some limitations to the geometrical structures of space, and I'm not sure if it would allow for wormholes, but it would still allow black holes to exist. The universe would be like a growing four dimensional ball with Big Bang in the middle at begining of time. Black holes would bend space backwards in time, all the way down to Big Bang. And the attraction in black holes could be coming from Big Bang itself which is presumably quite heavy. Anything entering a black hole could be traveling back in time to the very start of time, where they add to the mass that will in the past explode. (again?)

      It might require quite some imagination to understand this, but it surely makes sense to me.

      --

      Do you care about the security of your wireless mouse?
    5. Re:Reminds me of a story... by JohnsonJohnson · · Score: 5, Informative

      No.

      That's not a question in general relativity. The curvature of a spacetime can be measured without considering it as being embedded in manifold of higher dimension. How? Here is the common demonstration of the idea without using the language of math which makes the idea harder to convey. If you want a more rigourous explanation see here. Note that the curvature we are concerned with here is the Gaussian curvature which is intrinsic, ie it can be measured without considering directions outside of the dimension of interest.

      Consider the surface of sphere, any ball is a reasonable approximation. Now consider the following path. Starting at the equator while facing west (these are all well defined directions if you use the right hand rule and call north the direction of your thumb then east follows the curvature of your fingers and west is opposite east). Now go 1/4 of the circumference of the circle west, turn to face north. This is a 90 degree turn. Go to the north pole. Now turn 90 degrees again (again this is a well defined operation, when facing any direction a 90 degree turn is accomplished by orienting yourself such that the direction previously over your right shoulder is now the direction you are facing). Now continue to the equator. You should be at the original starting point, and another 90 degree turn will leave you facing west, your original direction of departure.

      So you've traced out a triangle: a closed path with three vertices, but you've made 3 90 degree turns so the sum of the interior angles is greater than 180 degrees in violation of euclidean geometry. Therefore you know your 2 dimensional world: which is the surface of the sphere, is curved. Note that is is not necessary for this surface to actually be curved "into" anything. If the sphere is the spacetime of a universe then there is by definition nothing outside of the surface of the sphere to consider, all of space and all of time are contained on the surface. The surface is still curved, but it doesn't "curve" into anything, that's just a property of the spacetime.

      I'm not sure I can make it any clearer, but if you consider Occam's razor you'll see that it doesn't make sense to thing about curved spacetimes as being embedded in some higher dimension. Since it is possible to measure curvature without appealing to a higher dimension (remember we never left the surface of the sphere in the above example) then you don't need the higher dimension, all the information required is contained in your local spacetime.

    6. Re:Reminds me of a story... by sg_oneill · · Score: 2

      Hell yeah. Greg Egan does my head in each and every time. Admittedly he does occassionally go off the rails with the maths and physics, but I kinda like that. The thing that amazes me with Egan is that for an author he really does understand his stuff. He publishes on physics, including all the mindboggling mega dimensional super flipout brainfuck stuff. His website (sorry no URL, google it) has all sortsa homespun java apps to illustrate the math in his books.
      For a real bender, try Permutation city where he posits a cellular automata simulation that kinda busts off into it's own reality due to the internal self sufficiency of it's math (yes I'm sure he's aware of philosophical-mathematical objections to this notion). It's a brainwarp of a book.

      --
      Excuse the Unicode crap in my posts. That's an apostrophe, and slashdot is busted.
    7. Re:Reminds me of a story... by invid · · Score: 2

      Thanks for explaining that, you did a good job. I always considered it necessary for a curved universe to curve into a higher dimension, and always wondered why scientists didn't announce things like "We know that there are higher dimensions because space is curved". It certainly does makes it easier to visualize curved space when you look at it like a 2d universe in a 3d one. Even with your example, your 2 dimensional universe does exist on a sphere. But the point is that something can behave like it is curved without actually being curved. It's just the way the universe behaves. However, while admitting that we don't require higher dimensions, I think it is more likely that they do exist if the universe behaves like it is curving into them.

      --
      The Moore-Murphy Law: The number of things that will go wrong will double every 2 years.
    8. Re:Reminds me of a story... by maryesme · · Score: 0

      However, while you may observe the curvature without leaving the 2-D space, the curvature can only exist within 3-D space. If this were not the case, how could you possibly have a sphere to begin your description.

      So, while we may observe the curvature of space without leaving 3-D space, I contend that there is necessarily a fourth dimension within which this curvature must take place.

    9. Re:Reminds me of a story... by SimCash · · Score: 1

      maryesme is, of course, correct. The example exactly demonstrates a technique for inferring a 3 dimensional space from two dimensional observations. We infer at least four dimensions based on our three dimensional observations. On the other hand, the higher dimensions are just a mathematical convenience that seems to fit observation, this does not mean they exist.

  9. hold up... by circletimessquare · · Score: 5, Funny

    so it's 5 am monday morning on the east coast and i decide to check out slashdot before going to bed for 4 hours of shuteye before work tomorrow (don't ask, crazy weekend). i am bleary eyed, brain dead, exhausted.

    and i read "The bounding hyperplanes can be extended infinitely so that they criss-cross through each other, chopping up hyperspace into many 4-dimensional 'chunks.' Again the inner chunks are finite, and they are distributed in shells around the core polytope."

    dudes! my functional iq right now is about 50! if you are going to post these kind of stories on slashdot, could you PLEASE post them around, say 3pm on a thursday? thanks ;-P

    i should be awake by then, and i promise i will come back and try to wrap my mind around this story at that time... grumble, grumble

    --
    intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
    1. Re:hold up... by Elbereth · · Score: 3, Informative

      That's nothing. I just took two Benedryl. I think I'll go to sleep now.

    2. Re:hold up... by Anonymous Coward · · Score: 0

      Sweet dreams.

    3. Re:hold up... by Anonymous Coward · · Score: 0
      Benedryl is for bitches, tramps, sluts, whores, and skanks.

      Nah... It's all about NyQuil! In the original Green Death fucking flavor! I find that 5 shots usually does the trick.

      "Big N, small y, big fucking Q! NyQuil NyQuil NyQuil, we love you, you giant fucking Q!"

    4. Re:hold up... by Crosis · · Score: 1

      Hey that depends on what time zone your in, ehh! For me it was posted at about 10pm, so I'm full up with caffeine ready to do about 5 hours of University assignments. So I think I'm triping out at the moment, ooh look at the pretty colours. Geez my hand is twitching so much I can hardly type. Getting back on topic (sorry), it is certainly an interesting bit of coding. It would be pretty cool as a screen saver (preferably using OpenGL or god forbid DX) for a bit more performance. Do you think they'll GPL the source?

  10. It's quite simple.... by Jeffv323 · · Score: 3, Funny

    Step 1: Make cool applet with shapes and colors.
    Step 2: Explain shapes and colors with big words and things nobody knows anything about ie: hyperplanes, polytopes, and the fourth dimension
    Step 3: .....
    Step 4: Profit!!

    --
    I'm a minister!
    1. Re:It's quite simple.... by Anonymous Coward · · Score: 0

      Oh no, the step-profit trolls are on the loose again!

    2. Re:It's quite simple.... by Anonymous Coward · · Score: 0

      1. Let loose step-profit trolls
      2. ...
      3. Profit!!!

    3. Re:It's quite simple.... by Anonymous Coward · · Score: 0

      What's step three?

      Jesus you gnomes need to think about these things before you start.

      p.s. Give me back my underwear you son's of bitches!

    4. Re:It's quite simple.... by Anonymous Coward · · Score: 0

      Actually, you CAN polish a turd. But it still smells, tastes, looks like, has the value of and -is- shit.

      - Cunt Mullet

  11. Re:Imagine NV30 images in 3D!!! by Anonymous Coward · · Score: 0

    These leaks should perhaps be viewed with 3D glasses, but yet more important - in the light of nVidia's financial turmoil in the stock market... ;)

  12. Aaahhh, now I see by RenHoek · · Score: 3, Funny

    It's one of those OpenGL Windows 95 screensavers! :) Why didn't you just say so?

    1. Re:Aaahhh, now I see by Jenova · · Score: 1

      Not really you see, running that thing will send WIndows95 to the 5th dimension!

    2. Re:Aaahhh, now I see by DjMd · · Score: 3, Funny

      Really?

      The BSOD (Blue screen of death) is the 5th Dimension?
      Cool. Bill Gates is Buckaroo Banzai!




      Oh come on you are just jealous that you didn't make the Buckaroo Banzai reference!

      --
      DJMD - The fourth man - Planetary
    3. Re:Aaahhh, now I see by JPriest · · Score: 1

      BSOD is dying.

      --
      Saying Java is nice because it works on all OS's is like saying that anal sex is nice because it works on all genders.
    4. Re:Aaahhh, now I see by f8xmulder · · Score: 1

      Anyway, Banzai travels to the 8th dimension, not the 5th, so you get a point for the great movie reference, but you lose a point for the incorrect dimension. D'oh! At least you still came out even.

    5. Re:Aaahhh, now I see by tlon · · Score: 1

      This applet has incredible depth if you crank up the detail level. It would make a sweet screen saver, if someone took the time to convert the Java applet into a more useable screensaver form.

  13. left out the most important part ! by Anonymous Coward · · Score: 2, Funny

    "Again the inner chunks are finite, and they are distributed in shells around the core polytope."

    uhh yeah, but it all depends on the capacitive current getting to the space modulator

    come on, lets do a thorough reporting job. You didnt even mention the fucking space modulator.

    1. Re:left out the most important part ! by Kredal · · Score: 2

      Oh, the Q-36 explosive space modulator? I'm going to use it to blow up the earth.

      --Marvin

      --
      Whoever stated that signature sizes should be limited to one hundred and twenty characters can just go ahead and kiss my
    2. Re:left out the most important part ! by howlingfrog · · Score: 1

      It's the Illudium Q-36 explosive space modulator, silly.

      --
      The original Howling Frog is a fictional character and has no UID.
    3. Re:left out the most important part ! by Kredal · · Score: 2

      I knew I was forgetting something... Thanks!

      --
      Whoever stated that signature sizes should be limited to one hundred and twenty characters can just go ahead and kiss my
    4. Re:left out the most important part ! by Anonymous Coward · · Score: 0

      you are both silly :P

      It's "The Aludium Q36 Explosive Space Modulator"

    5. Re:left out the most important part ! by Anonymous Coward · · Score: 0

      You can try to use the Aludium Q36 Explosive Space Modulator to blow up the world, but I'll foil your cunning plot by reversing the polarity of the flux capacitor, works every time.

  14. ! Warning ! by BoBaBrain · · Score: 2

    Looking directly at four-dimensional stereograms can *really* screw up your eyes. Caution or strong hallucinogenics advised.

    --
    I am a Karma Library.
  15. 4-D Pr0n by Jeffv323 · · Score: 1

    It's already been invented. It's quite simple really. To travel forward in the 4th dimension, simply insert your pr0n tape into the device and hit Fast-Forward. To travel backward in the 4th dimension, hit Rewind.

    --
    I'm a minister!
    1. Re:4-D Pr0n by Anonymous Coward · · Score: 0

      Pictures are 2-dimensional, thus pr0n video is 3-dimensional. You'll have to try much harder to experience the 4th dimension.

    2. Re:4-D Pr0n by Jeffv323 · · Score: 1

      No, the actors^H^H^H^H^H^H pornstars are in the third dimension while filming, you use the VCR to travel in the 4th dimension (time.)

      --
      I'm a minister!
  16. You don't need 3-D glasses... by AaronBaker2000 · · Score: 5, Informative

    If you set the Stereo mode to "Cross-eyed," you can view the picture in 3-D using the Magic Eye technique.

    1. Re:You don't need 3-D glasses... by Jugalator · · Score: 2

      I knew about that technique and tried but failed in getting any 3D effect like usual. I think it's because I have crystal clear vision on my left eye and quite poor on my right. I think that method requires you to have about the same vision on both eyes.

      Someone buy a new right eye for me :)

      --
      Beware: In C++, your friends can see your privates!
    2. Re:You don't need 3-D glasses... by flonker · · Score: 5, Funny

      Simple solution. Stick a crayon in your left eye. That'll fix things real good.

    3. Re:You don't need 3-D glasses... by BJH · · Score: 1

      I got much better results with the 'Parallel' method. 'Crosseyed' seemed to turn parts of the object inside-out (not on purpose... I think), whereas parallel looked great.

    4. Re:You don't need 3-D glasses... by Grandpa+Jive · · Score: 1

      Hey how about that? Its a Schooner!

    5. Re:You don't need 3-D glasses... by Anonymous Coward · · Score: 0

      Cross-eyed seems to be easier for some persons to do.

      Only us superhumans can see the magnificent parallel!

    6. Re:You don't need 3-D glasses... by Crowley · · Score: 2, Informative

      Bzzzt. Wrong. I've got *extremely* poor vision in my left eye (very astigmatic in my left eye, on top of long sightedness in both eyes). With my glasses on, using the crosseyed method I see a 3D image.

      I reckon you could do with going to see an optician...

      --
      Caffeine fault: operator dumped
    7. Re:You don't need 3-D glasses... by Anonymous Coward · · Score: 0

      Uh, smart ass, not every vision problem can be fixed with a pair of glasses. I'm in the same boat as the original poster, I have perfect vision in my left eye, but my right eye is poor enough for me to be considered partially blind(*).

      I have a hole in my retina. Glasses cannot fix it. I lost the ability to "see" magic eyes when that hole was created.

      Footnote: The left eye compensates, and I have never had any problems; I can still sit in front of a monitor for 12 hours straight!

    8. Re:You don't need 3-D glasses... by Kredal · · Score: 1

      Ha ha ha, you dumb kid.. that's not a schooner, it's a SAILBOAT!

      (before you mod me down, realize I'm quoting a movie)

      (ok, mod me down as off topic, but not as troll.. thanks)

      --
      Whoever stated that signature sizes should be limited to one hundred and twenty characters can just go ahead and kiss my
    9. Re:You don't need 3-D glasses... by Anonymous Coward · · Score: 0

      Actually, "Magic Eye" type 3D images use the Parallel mode. You're not quite crossing your eyes in a Magic Eye, you're focusing behind the image. Whereas in Cross-eyed, you're crossing your eyes to focus in front of the image.

      If you're using the wrong technique, you can tell immediately because everything that looks like it's supposed to pop out looks concave instead.

      Personally, I find Parallel to not only be easier on the eyes, but it makes the image appear larger. Plus it's easy. Just focus on your reflection in the screen. Of course, most people can cross their eyes just as easily, but that technique is harder on the brain. It's true, ask your local specialist.

    10. Re:You don't need 3-D glasses... by Anonymous Coward · · Score: 0

      Way to get a hole in your retina, fag!

    11. Re:You don't need 3-D glasses... by Walt+Dismal · · Score: 1

      I use the Cowboy Neal technique to view hyperspace. Cross-eyed and painless.

    12. Re:You don't need 3-D glasses... by Anonymous Coward · · Score: 0

      >Only us superhumans can see the magnificent parallel!

      I think Quake1 had a parallel view setting of some sort (had to tweak somewhere in the settings). I remember playing it (or was it Quake2?) in parallel view - it was wicked to actually see grenades coming toward you...

    13. Re:You don't need 3-D glasses... by Jugalator · · Score: 2

      Yes, we apparently have similar problems. I too compensate with the other eye and with both I can see perfectly fine. I don't get headaches, etc either.

      And to the poster saying I was wrong, well, you said you used glasses. Wouldn't that improve sight on your "bad" eye good enough to make them equal? I'm not using glasses since there is normally no need to.

      --
      Beware: In C++, your friends can see your privates!
    14. Re:You don't need 3-D glasses... by Jugalator · · Score: 2

      .. and of course I've been to an optician, but I didn't demand glasses to see those special 3D images. ;) I saw good enough in traffic, etc he said, so... :)

      --
      Beware: In C++, your friends can see your privates!
    15. Re:You don't need 3-D glasses... by Anonymous Coward · · Score: 0

      Yeah? I got a five figure settlement and made a medical journal.

      If you like, I'll show you how I got it.

    16. Re:You don't need 3-D glasses... by hopews · · Score: 1

      Focusing on my reflection in the screen would be a whole lot easier if I didn't have one of these damned anti reflective coatings on the monitor. I can't see even the slightest hint of my reflection. Don't they think about magic eyes when they build these things? Maybe I should ask my boss for an office with a window.

      Fortunately I have no problems crossing my eyes.

    17. Re:You don't need 3-D glasses... by Verne · · Score: 1

      Almost...

      You will get better results using the magic eye technique on "parrallel" as BJH further down this thread discovered.

      A common misconception of the magic eye technique is that you can go cross-eyed to see them. While this is correct, the images are inside out as the wrong eye is looking at the wrong image.

      Magic eye pictures require the left eye to look at the left image, and the right eye to look at the right image (Think of looking past the picture instead of in front)

      It's harder to get the hang of, but much easier on your eyes for prolonged viewing.

      I'm still hanging out for a magic eye movie...

      --


      There are only two things in this world that smell like fish. And one of them's fish...
    18. Re:You don't need 3-D glasses... by p3d0 · · Score: 2

      Actually, it's the opposite of the Magic Eye technique. This is crosseyed, while Magic Eye is walleyed.

      --
      Patrick Doyle
      I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
  17. As if Monday morning weren't bad enough... by Anonymous Coward · · Score: 0

    ...now you go and give me a bastard headache looking at 3D images of a 4D environment on a 2D screen. Yowch.

  18. Alternative to 3D glasses? by legomad · · Score: 1

    I don't have a pair of 3d glasses, is there any kind of computer screen filter that has the same effect? Or do one's actual eyes need to be cross-eyed?

    1. Re:Alternative to 3D glasses? by Anonymous Coward · · Score: 0

      Get a sheet of overhead projector film, cut out two squares of it, and use OHP marker pens to colour one of them red and the other one blue (or green). Stick the coloured films over a pair of spectacles. You may look silly, but it works.

    2. Re:Alternative to 3D glasses? by philipsblows · · Score: 2

      I found the Parallel (sometimes called "Wall-Eyed") mode to be the best, especially at this early hour. If you get your head in just the right spot and relax your eyes just right, you get a decent 3D effect without the odd color effects of the old 3D glasses method (which also works, but to me it looks odd).

      If you've viewed random dot autosteroegrams using the wall-eyed technique (or the cross-eyed technique) this is the same thing, except the movement will be a distraction.

      As always, YMMV

    3. Re:Alternative to 3D glasses? by af_robot · · Score: 2, Funny

      I don't have a pair of 3d glasses, is there any kind of computer screen filter that has the same effect?

      Yeah, they call it "Alcohol"

  19. Time Cube by Mark4ST · · Score: 1


    This sounds alot like Gene Ray, of Time Cube. Creepy, man.

    1. Re:Time Cube by betatron · · Score: 0

      Not really. The author didn't insult your intelligence yet, "because you are two stupid to understand the Time Cube."

  20. Um, no it doesn't. by legomad · · Score: 1

    How exactly do you think they are similar?

  21. This is not new! by scrod · · Score: 1

    This isn't new. There have been real applications and Java applets, too that have been able to do this sort of thing. I've got an old app for the classic Mac OS called "HyperSpace" that does exactly this (draw multiple 3D cross-sections of 4-D hypercubes). It's a really, really old app.

  22. Hypercube by imevil · · Score: 3, Informative

    Here

    Less pretty but more understandable

  23. Edwin Abott would've loved it by SpatialJ · · Score: 3, Informative
    It's a pity E. Abott, author of "Flatland: A Romance of Many Dimensions" has died some 80 years ago. Maybe he even would have sold the film-rights of his n-dimensional love story "soon showing in java-applet near you".

    BTW: things like the famous Stereoscopic Animated Hypercube have been around for quite some while. There even is a game around to be played.

  24. Well, it is new to me. by legomad · · Score: 1

    Thanks to slashdot many people can actually find out about it.

    1. Re:Well, it is new to me. by scrod · · Score: 1

      Yeah, well slashdot should've told them sooner! I try to explain higher dimensional space to people and they just blink and say "but I thought the fourth dimension was time!"

    2. Re:Well, it is new to me. by DrVxD · · Score: 2

      Isn't that what search engines are for?

      --
      Not everything that can be measured matters; Not everything that matters can be measured.
    3. Re:Well, it is new to me. by protonman · · Score: 1

      > "but I thought the fourth dimension was time!"

      Jeah I hate that. So when people say that, I always ask what the second dimension is called. Is it width? heigth? Most of the time they then realise naming dimensions that way is rather silly.

      --
      The man of knowledge must be able not only to love his enemies but also to hate his friends.
  25. It is difficult, but... by tanveer1979 · · Score: 4, Interesting

    the thing about opening our minds is right.
    We have always lived in three dimensions, so visualizing 4 dimensions Per Se is almost impossible coz our nuerons have been hardwired for 3 dimensions. So we can observe 4 dimensions in transit. For example if youwere a 2 dimensional being(thats not possible coz 3 is the minumum number of dimensions to sustain life) and a 3D sphere passed through your space, you will see a point, growing into a circle and then again into a point.
    So if a 4D object came it would look like a morphing 3D object.
    If mankind were able to create and use 4D's travel would be a whole new frontier. Esp since space-time is curved, Just imagine traveling a million miles instantaniosly
    Confused! Go through stephen hawkings works! you will be even more so :-)

    --
    My Aurora : http://www.youtube.com/watch?v=o91ZsGwJYyg
    FB : https://www.facebook.com/TanveersPhotography
    1. Re:It is difficult, but... by philipsblows · · Score: 2

      Actually, a sphere passing through a 2D world would appear to be a point, then a line of increasing length, then decreasing length, then a point again.

      Or maybe that is a 3D'er view of things? I used a compact disc and a pencil to demonstrate this recently, and if my 2D example beings lived in the plane of the CD, then the pencil passing through the center of the CD would look similar to a sphere passing through a similar plane, if viewed along the plane (as a resident of said plane).

      A long time ago, I read this silly book called Planiverse about a fictitious 2D world. The author presented it in a fantasy-like format about encountering 2D beings via a computer, but the concepts were presented such that a young person (as I was then) could see what was going on. For what it's worth...

      By the way, I just looked, and it Planiverse is still around. I had never read Flatland, but that is linked there on that Amazon page as well.

    2. Re:It is difficult, but... by Anonymous Coward · · Score: 0

      The line would be a 1d projection of the 2d object. We see our 3d world as two slightly parallaxed 2d projections from which our brain conveniently reconstructs some 3d information. A sphere passing through a 2d world would be seen as two parallaxed lines from which depth information would be reconstructed, giving the impression of a circle.

    3. Re:It is difficult, but... by andhar · · Score: 1
      For example if youwere a 2 dimensional being..., growing into a circle and then again into a point

      Wrong. If you were a 2D being and a sphere assed through your plane you'd see a dot grow into a long "wall" or "line", disappearing into a dot again.

      The book Flatland (available online in its entirity) covers all the nuances of the 2D lifestyle.

      --
      Vaya con huevos, my darling.
    4. Re:It is difficult, but... by Genom · · Score: 2

      We have always lived in three dimensions...
      So if a 4D object came it would look like a morphing 3D object.

      Actually, if you define time as the 4th dimension, we *are* in fact 4-dimensional beings (and perceive our world in 3-space, although we are capable of perceiving motion over time, which could be argued as a 4th-dimensional perception...). We indeed do appear in 3-space as a "morphing" 3D object -- think of how a human is born, grows, matures, and dies as the "motion".

      Of course, I'm no mathemetician or physicist, so I have no idea as to whether the "time as the 4th dimension" thing is even valid, but at least it's something fun to ponder on the long commuter rail trip =)

    5. Re:It is difficult, but... by Anonymous Coward · · Score: 0

      How is this so?

      Slice a sphere with a 2 dimensional plane and you get a circle

    6. Re:It is difficult, but... by psych031337 · · Score: 3, Insightful
      We have always lived in three dimensions, so visualizing 4 dimensions Per Se is almost impossible coz our nuerons have been hardwired for 3 dimensions.


      Breaking up these limitations is not as hard as it might seem. The traditional length X width X depth is just an example of a 3d room. I understood multi-dimensionality with this simple analogy:

      Imagine the "room of cookies"

      1st dim: color (red, green, blue,...)
      2nd dim: shape (round, square, triangular,...)
      3rd dim: consistency (very hard, hard, soft,...)
      4th dim: size (from very small to very large)

      There you have it. A 4dim room that can be used to express any kind of cookie in a mathematical vector. For adding more dimensions all you have to make sure is that the new dimension os orthogonal, which means that the new component/unit has to be linear independent of all the other components/unit (which could for instance be the 5th dimension of texture (like smooth, rugged, etc.)

      (Not an native english speaker, so please excuse me for using incorrect/half correct words.)
      --
      +++ath0
    7. Re:It is difficult, but... by dbarclay10 · · Score: 2

      This guy doesn't know what he's talking about, he's just trying to sound smart.

      Please ignore him.

      --

      Barclay family motto:
      Aut agere aut mori.
      (Either action or death.)
    8. Re:It is difficult, but... by Anonymous Coward · · Score: 0

      Only if flatland does not have stereovision will a sphere be seen as a line without information about its 2-dimensional shape.

    9. Re:It is difficult, but... by vjzuylen · · Score: 2, Insightful
      Actually, a sphere passing through a 2D world would appear to be a point, then a line of increasing length, then decreasing length, then a point again.
      If 2D lifeforms did exist (Planiverse suggests they would need zipper-like 2D organ structures) it's quite likely they would have some form of 'depth' perception - along a plane, of course. A sphere intersecting with their world could indeed be recognized as a circle, much like our brains can recognize the depth difference between a ball and a flat disc. The interesting thing about a book like Planiverse is that it inspires you to think about higher dimensions, using the simple 2D to 3D examples in the book as analogies. In my opinion, this serves as a better starting point for learning about the fourth dimension than any visualization applet.
      --

      Hee-hee. Dying tickles!
    10. Re:It is difficult, but... by dollargonzo · · Score: 1

      there is a big difference between orthogonal and lineraly independent. and it DOESN'T have to be orthogonal. there is no reason a new dimension should be entirely perpendicular. it just needs to be off the previous hyperplane, aka linearly independent. sure, u can *make* it orthogonal, but there is no need.

      QED

      --
      BSD is for people who love UNIX. Linux is for those who hate Microsoft.
    11. Re:It is difficult, but... by n-baxley · · Score: 2

      For example if youwere a 2 dimensional being(thats not possible coz 3 is the minumum number of dimensions to sustain life) and a 3D sphere passed through your space, you will see a point, growing into a circle and then again into a point.

      Actually, all you would see was a line that got bigger and then smaller. That assumes that you are a 2D being living in a 2D world. In that world, you would only be able to see things from along the plane that you live in. However, if the sphere passed through a plane that was perpendicular to yours, you would see what you describe. For more info on this, read the book Flatland. An interesting read for stretching your mind and pretty funny in parts. At least for a /. crowd.

    12. Re:It is difficult, but... by Java+Pimp · · Score: 1

      Actually, the world you describe is 3 dimensional, the third being time. A 2 dimensional being would not be able to see the point morph into a circle and back to a point. Nor would the 2D being see a point morph to a line and back. To see anything would require a 3rd physical dimension since the 2D plane is infinitely thin. Possibly the 2D being may be able to detect a disturbance but that would be about it.

      We as 3D (physical - 4th dimension temporal) beings can observe this phenomenon on a 2D (physical - 3rd temporal) universe because we are outside that universe. Likewise in order for us to view a similar phenomenon on our own 4D universe, we must step outside our universe into a 5D universe. We may be able to detect a disturbance but we could never physically observe the phenomenon. Not even with a cute java applet.

      --
      Ascalante: Your bride is over 3,000 years old.
      Kull: She told me she was 19!
    13. Re:It is difficult, but... by Paolomania · · Score: 1

      For example if youwere a 2 dimensional being ... and a 3D sphere passed through your space, you will see a point, growing into a circle and then again into a point.

      If you are a 2D being existing in some 2D subspace which a sphere is passing through, you do not have the advantage of an external view of the subspace in which you exist. Its not like you are looking at a sheet of paper - its like you are on the sheet of paper. what you would see is a point growing to a line then shrinking back to a point. If you had stereoscopic 2D vision you would be able to see how far away it is, and perhaps that it has a circular curvature to it - but that would all depend on the information you brain could extract from the lighting and texture on the line.

    14. Re:It is difficult, but... by Alsee · · Score: 2

      3 is the minumum number of dimensions to sustain life

      Ok, I'll bite.
      Why is 3 is the minumum number of dimensions to sustain life?

      hehe, this ought to be amusing.

      -

      --
      - - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
    15. Re:It is difficult, but... by seanadams.com · · Score: 2


      Why is 3 is the minumum number of dimensions to sustain life?


      I can't answer this completely, but trying to draw a 2D animal with a digestive tract will give you an idea of what is meant by that statement.

    16. Re:It is difficult, but... by Alsee · · Score: 2

      Ah yes, the good old "mouth/digestive tract/anus would cut it in half" argument.

      Lets see how many ways I can shred that one off the top of my head...

      1: Photosynthisis does not require a digestive tract.
      2: Many bacteria re-seal the "mouth" opening and digest in a completely enclosed vacuole. The vaculoe merges with the outer surface creating a temporary "anus" to expel the waste.
      3: Many bacteria (and to a certain extent some flies) preform digestion OUTSIDE their bodies. They excrete digestive juices and adsorb/swallow the pre-digested food.
      4: Hydra and some other animals combine mouth and anus as a single opening. They are bag shaped. They swallow food, digest it, and "vomit" the waste back out.
      5: Cutting the creature in half may not be prohibitive if the two halves are held together by adheasion, suction, or some attactive force.
      6: You are assuming life has to resemble us.
      7: You are assuming the usual laws of physics apply. I'd say that's a bad assumption since we are already talking about some sort of 2D universe or enviornment.

      -

      --
      - - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
    17. Re:It is difficult, but... by PlaysByEar · · Score: 1
      3 is the minumum number of dimensions to sustain life
      Ok, I'll bite
      Okay, I'll bite off the other end. Is our life sustaining universe only "3-D"? Could something from an additional dimension (which we don't see, but exists) be necessary for sustaining life?
    18. Re:It is difficult, but... by seanadams.com · · Score: 2

      Ah yes, the good old "mouth/digestive tract/anus would cut it in half" argument.

      I agree - it's a very simplistic argument which makes a lot of assumptions about the definition of "life". I don't really agree with the assertion, since I have a very broad definition of what I would consider to be alive. But it's an interesting idea anyway.

    19. Re:It is difficult, but... by Tablizer · · Score: 2

      (* There you have it. A 4dim room that can be used to express any kind of cookie in a mathematical vector. For adding more dimensions all you have to make sure is that the new dimension os orthogonal......*)

      OOP fans don't seem to get this. Their single-demensioned taxonomy that they use for polymorphism assumes that a single dimension is sufficient. (I know, some OO fans realize that simple-minded textbook polymorphism is not sufficient, but their "fixes" are often worse than the desease in many cases.)

      Polymorphism is pretty much one-demensional, while the real world is multi-demension (WRT number of orthogonal or semi-orthogonal factors which influence behavior and grouping.)

      Stepanov (of STL fame) has recognized this also when complaining about OOP. OO authors like Meyer gloss over it or pretend like it is a non-issue using wiggle words.

      OOP has dimension problems. Your cute shape and animal taxonomy examples can't scale beyond the dimension of the demonstration. (They pick examples where one dimension just happens to reign supream).

    20. Re:It is difficult, but... by P-Nuts · · Score: 1

      Well, I don't know about life, but take a one-dimensional universe first. Place a bunch of points in it (they will all be on a straight line). Each point can only be connected with two neighbouring points.

      Now do the same with a two-dimensional universe (try with pen and paper). Connect one point to all of the other points without any lines crossing. No do the same for another point (this should be possible). However, there will no longer be any other way of connecting a third point with all the remaining points.

      I believe that it is possible to connect all points to all others in three dimensions, which is probably handy for life and stuff.

    21. Re:It is difficult, but... by tcc · · Score: 2

      > For example if youwere a 2 dimensional being(thats not possible coz 3 is the minumum number of dimensions to sustain life)

      My ex girlfriend could prove you wrong :)

      (sorry couldn't resist :) )

      --
      --- Metamoderating abusive downgraders since my 300th post.
    22. Re:It is difficult, but... by SectoidRandom · · Score: 2

      To grasp the 4D space idea, I always like the example of the unfolded cube.

      If you were to be a two dimentional creature, you could not see a cube as anything more than a standard 2d square. But if I were to unfold that cube into two dimentions, you would see a cross like 2D shape like remember when in primary school you made those cubes from paper? With four squares up and to the left and right of the second square down another square on each side. (giving a t shape?)

      Now just imaging in a 3D world, take a 4D cube and unfold it, now you have a simiar cross shape, but with 4 CUBES high, with a cube connected to each side of the second cube down!

      The only other thing you have to accept is that it is not possible for you to percieve 4 dimentions, so only try to percieve it in 3 dimentions..

    23. Re:It is difficult, but... by Guppy06 · · Score: 2
      It's amazing how high you can get modded up around here when pretend you know what you're talking about...

      "the thing about opening our minds is right."

      Opening one's mind is one thing. Recreational drug use is something else entirely.

      "We have always lived in three dimensions,"

      I don't know about you, but I was born and raised in 4-D space-time. If you live in three dimensions, then your life would be (by definition) quite short. Just because our perception of time differs from length, bredth and height doesn't mean that it's not a dimension just the same.

      Don't think of 3 * 10^8 m/s as a speed limit, think of it more like "300,000 km = 1 s."

      "For example if youwere a 2 dimensional being(thats not possible coz 3 is the minumum number of dimensions to sustain life)"

      Look, string theorists are having a hard enough time trying to figure out if we're living in 11 or 12 dimensions (let alone whether we're talking about space-like or time-like dimensions), the quantum mechanics folks are still scratching their heads trying to figure out what happens to all those other states that get resolved away, so could you please hold off on the xenobiological conclusions at least until those two juries come back?

      "and a 3D sphere passed through your space, you will see a point, growing into a circle and then again into a point."

      ... so you'd see a shape that changes over (wait for it...) TIME! Hey, look folks! This kid just proved 1=1! Give him a medal!

      And what's this "time" I speak of? Why, it's the fourth dimension, it's that thing you have to add to space before you can start talking about constants in this relativistic universe of ours. It's the dimension along which our universe is expanding.

      "So if a 4D object came it would look like a morphing 3D object."

      Morphing? As in "change in time?" As in "a change in space-time coordinates?" That's like saying "You wouldn't see a cone, you'd see a circle whose radius changes with height." What's "height" you ask? Why, it's the third dimension! Dur!

      "If mankind were able to create and use 4D's travel would be a whole new frontier."

      I use 4-D travel every time I get up and walk to the damn bathroom. Same thing with that morning communte. Hell, I sit on my ass and do nothing and I'm whipping about through space-time like a bat out of hell. Moving from point (x1, y1, z1, t1) to (x2, y2, z2, t2) is by definition moving through all four dimensions of space-time.

      "Esp since space-time is curved"

      You came so close to realizing how silly your whole post sounded... so close yet so far...

      "Just imagine traveling a million miles instantaniosly
      Confused! Go through stephen hawkings works! you will be even more so :-)"


      You just used the word "instantaneously" in a sentence. You obviously need to graduate from Einstein before trying to figure out Hawking.

      Burn, karma, burn!

    24. Re:It is difficult, but... by Alsee · · Score: 2

      take a one-dimensional universe first

      I suggest that life could function even in a one-dimensional universe, given a sufficiently rich set of physics. Sceptical? Consider this - in our universe there are things that can pass though each other. Light. Sound. Forces like magnetism that can affect things at a distance even when there is something in the way. Maybe one-dimensional life would be made of "stuff" that can pass though other "stuff". Perhaps in some cases it could pass through something and be unaffected. In other cases maybe it "eats" some energy from it in the process.

      Being "trapped" in a one-dimensional line may not be as restrictive for "them" as it would be for us.

      -

      --
      - - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
    25. Re:It is difficult, but... by Anonymous Coward · · Score: 0

      blah blah blah.... I dont know what I'm talking about ^H^H^H^H^H^H blah blah blah I think I'm cool yeah man

  26. Simple question.... by Lumpy · · Score: 2

    I would assume that if multiple dimensions exist, then we actually live in them already, it's just that we only have the ability to percieve the 4 obvious dimensions to us. While the other Nth dimensions are still existing just not eaqsily percieved by us. (AS in that quarks may in fact exist in the "4th dimension" (or properly termed by us as the 5th dimension.... don't start with the classic rock jokes!!) which would easily explain how some of them can exist in 2 physical "3d" locations at once.. existing in the "4d" space there will be multiple intersections from the "3d" space.... espically if the particle was elongated.

    Is this a correct assumption?

    --
    Do not look at laser with remaining good eye.
    1. Re:Simple question.... by Solaristrum · · Score: 1

      Your general inclination about high energy particles is in line with current theoretical thinking. Today, most popular theories about physical nature are based on multiple higher dimensional universes (usually 10 or 11 dimensions including the three spatial and one temporal that we know about) that permit the existence of our current physical universe within them. The higher dimensions are generally thought to be collections of "super symmetric strings" which vibrate in various different modes. Occasional vibrations intrude into our classical four dimensions particuarly in high energy situations like the particle accelerators that permit us to see quarks. The difficulty is that there are many of these competing ten dimensional spaces that can give rise to our universe so it is tough to tell them apart and the energy to do so would be so prohibitive that we will not be able to do it for thousands of years. Thus these notions remain embedded purely in the theoretical world.

      Of course, this is just my understanding from what I read a couple of years ago. I think that "strings" my be superceded by "M-theory" or something more esoteric these days.

      --
      Solaristrum: One who has spent way too long staring at the Sun
  27. Using 3D senses to visualize 4D by thaddjuice · · Score: 1

    If you think about it, it doesn't really make sense to be able to visualize a four-dimensional object using sight. Why? Because sight is a two-dimensional sense that on a daily basis we use to visualize three-dimensional space. Visualize trying to understand a 3D shape looking at a pinhole view of it (1D to 3D). Can't really be done, certainly not without a ton of staring at it.

    Seeing as how it's so difficult to jump two dimensions in visualization, how do we do it? We use the only 3D sense that we've got... touch. Since we can "see" all sides of an object at once using touch, then we are truly experiencing that object in 3D.

    So create some kind of device that you hold in your hands and moves around to simulate a hypercube. Simple answer :).

    --
    Find me in ~/.sig
    1. Re:Using 3D senses to visualize 4D by jo-do-cus · · Score: 1

      you are not really right about this. Sight is not a truly 2-dimensional sense because we have 2 eyes. This makes it possible, for example, to determine which one of two objects is the furthest away from you. So our brain does have some 3d-information from that. Because we do not get a complete 3d-picture, I would rather call sight a 'partly 3D' sense.

      Besides that, we also get some 3d information form hearing (yes we do!) and proprioception (which is kind of like feeling your body's position & balance). And then, when you move your head, you can very effectively add information about the 3d layout of your surroundings.

      Like someone argued before me, the real problem is that we try to make a picture of a 4-dimensional object by projecting a 3d projection of it onto a 2d surface (paper or screen). We really should use a 3d-printer that just 'prints' the 3d projection. The fourth dimension could then be added by colour, or time, or whatever.

      by the way, i do believe those 3d-printing devices exist.

  28. Re:Hi handsome by KinkyClown · · Score: 1

    Somehow my pride of my country (Netherlands) has been deministed :(

  29. This was an old college argument... by Thalia · · Score: 5, Insightful

    We used to argue this in the computer science lab at college. Can the human mind gain visualization skills in four dimensional geometry? We came up with the following interesting answers:

    1. It's hard. We never see four diminsions. The brain would keep wanting to make one dimension some known continuim such as time, a color sequence, tone, or intensity. Only after this intermediate step would you get a true four dimensional geometry in your head.

    2. You would need to have a true 3D display. Current rendering of three dimensional pictures flattened onto simple two dimensional screens would never work. Imagine using a laser pointer as a point source, and imagine that you had never seen a three dimensional object; now draw a three dimensional picture of a pick-up truck using the laser pointer. At the time, we were trying to get a simple three dimensional output, like <a href="http://www.stereographics.com/frames/frame-p rod.html">Crystal Eyes</a>. Now there are liquid crystal on silicon solutions that are much cleaner, if not cheaper.

    We were students once, and poor.

    1. Re:This was an old college argument... by psavo · · Score: 2

      2. You would need to have a true 3D display.

      This is a requirement that fascinates me, how are you supposed to perceive something in 3D, when your receptors (eyes, retina) are 2D by their nature.
      As far sa my brains go, 2D surface emulator will do that just fine, so 3D screen is just a fancy toy that eases manipulation by having better interface to Real World(tm) than 2D screen.

      --
      fucktard is a tenderhearted description
    2. Re:This was an old college argument... by forsetti · · Score: 1

      Each eye is a 2D receptor, but the use of two 2D receptors allows the extrapolation of 3D data. Although the eye cannot do 3D, your brain can. And we (as humans) do not receive "raw data" from our eyes, but rather our brains' interpretation of that data.

      --
      10b||~10b -- aah, what a question!
    3. Re:This was an old college argument... by psavo · · Score: 1

      So 2x 2D monitors will do it. Still no need for 'real' 3D monitor.

      --
      fucktard is a tenderhearted description
    4. Re:This was an old college argument... by mobets · · Score: 1

      yes, but only if we can set it up so that each eye only sees one monitor and the two images line up. also, the two screens would have to be rendered from two points of veiw. This is what most VR sets do.

      --

      It was me, I did it, I moved your cheese
    5. Re:This was an old college argument... by AffineTransform · · Score: 1
      1. It's hard. We never see four diminsions.

      Guess what - we never see three dimensions either. We see a 2-D projection of 3-D space, and use stereoscopic vision (i.e. 2 eyes), motion, and pattern recognition to build a mental model of the 3-D structure of the world around us.

      Using the data visualization technique known as the Grand Tour, one can visualize things in arbitrarily high dimensions. See the GGobi software for examples.

    6. Re:This was an old college argument... by UranusReallyHertz · · Score: 1

      I always wondered what the effect is if the two views are rendered using a distance greater than that between people's eyes? I'm thinking it would give you one hell of a headache, and be pretty weird.

      --
      Smoking is an expensive, slow, and unreliable method of suicide.
    7. Re:This was an old college argument... by cheese_wallet · · Score: 2

      I saw a show about an experiment where they had a person wear strange glasses that through the use of mirrors made everything appear upside down.

      It took about a week for the person to completely adapt to perceiving everything upside-down. I imagine it would be the same for rendering the view for each eye as being greater than the normal distance.

      Besides, not everyone's eyes are the same distance apart, yet the brain has coped quite well.

    8. Re:This was an old college argument... by UranusReallyHertz · · Score: 1

      True, but I was thinking of HUGE distances, like 3 feet, or 10, or a 100, etc. Or you could try really freaky things like place each "eye" so that the lines of sight are perpindicular, or even point them at each other to see both sides of an object at once.

      --
      Smoking is an expensive, slow, and unreliable method of suicide.
  30. Re:I want it to be pizza by Anonymous Coward · · Score: 0

    I'm looking forward to attending your lecture on the topic. Please remember to give enough examples.

  31. God by VirexEye · · Score: 2

    After stareing at this for about 30 mins it made me wonder if God is a 4D being..

    1. Re:God by GigsVT · · Score: 1, Funny

      If by 4D you mean totally fictional and only created to serve social leader's agendas and scare ignorant masses into submission through threats of eternal punishment, then yes, yes he is.

      --
      I've had enough abrasive sigs. Kittens are cute and fuzzy.
    2. Re:God by Anonymous Coward · · Score: 0

      SHE is!

    3. Re:God by xscottyx · · Score: 2, Interesting

      IF there is a god, I imagine that he would have to be 5D or 6D. I say that because I think that we ourselves are 4D beings, since we experience time. I imagine that God would be 5D, since I don't think that he would be limited to any particular time like us. I think that God could also be 6D, since I can't see God as being limited to one universe, but that depends on whether or not there is a multiverse. Is that weird?

    4. Re:God by Anonymous Coward · · Score: 0

      Man, what's your gripe with the forth dimension, anyhow? Hasn't time been kind to you? :)

    5. Re:God by Anonymous Coward · · Score: 0

      Yes, yes it is.

    6. Re:God by Anonymous Coward · · Score: 0
      Wow. Somebody woke up on the cranky and cynical side of life.

      Here, have an M&M.

    7. Re:God by Archfeld · · Score: 2

      I was just in an argument with a very smart mathmetician and long after he lost me in proofs he deigned to lower himself and explain to me what he actually meant. From what I understand it boils down to this...

      Time is not a dimension, as it is merely an expresion of the relative speed of movement.

      Now I am not sure if that makes any sense in reality but my heads hurts to much to keep thinking about it.

      --
      errr....umm...*whooosh* *whoosh* Is this thing on ?
  32. I have a large collection of 4D media by guttentag · · Score: 5, Funny
    Each one takes a 3D image and progresses along a fourth dimensional plane I like to call:

    <fingerquotes>TIME<fingerquotes>
    This combination is stored in a media format I call a:
    <fingerquotes>MO-VIE<fingerquotes>
    4D is very subjective, so long as you are allowed to define the four dimensions involved.
    1. Re:I have a large collection of 4D media by Anonymous Coward · · Score: 0

      Not so fast, hotshot. A movie is 2D by time, so it's effectively a 3D medium (by your clever redefinition).

    2. Re:I have a large collection of 4D media by elzahir · · Score: 1

      Ah, but is it an... EVIL movie?

      --
      For a successful technology, reality must take precedence over public relations, for nature cannot be fooled - R Feynman
  33. space and time by Erpo · · Score: 1

    It's talking about a shape in 4 spatial dimesions, not 3 spacial dimensions and one time dimension. Also, movies aren't 3d - not even those red-cyan ones. If movies were truly 3d, you'

    1. Re:space and time by Erpo · · Score: 1

      d be able to see the entire scene in the movie from all angles at the same time. Not really of course, since you can't see in 3d, only two 2d images, but you get the idea.

      Sorry about the split post - I guess I'm not very coordinated at 4am :P.

  34. ur so smrat! by Anonymous Coward · · Score: 0

    i finde ur ideers intreeging an wants to sib...sebsri...subscrib to ur news leter!

  35. Re:I don't understand(fixed link) by shftleft · · Score: 1

    to learn more read some Kaku - one of the foremost scientist on hyperspace....(fixed link from previous post.

    Hyperspace

    --
    People who have witty things here blow.
  36. 4-D / Banchoff by Anonymous Coward · · Score: 0

    Hey, did anyone tell Tom Banchoff@Brown University
    about this? He is the master when it comes to
    4-d visualization. I still remember the opening
    celebration of the Thomas J. Watson Jr. Center
    for Information Technology at Brown when he
    put on a music/graphics show projected outdoors
    onto these huge screens.

    http://www.math.brown.edu/~banchoff/

  37. Extrapolation for 4d/5d sound by metlin · · Score: 3, Interesting

    There was something similar done by a guy called Luke Dahl, only it was for audio.

    It was a Markhov chain extrapolation of the 3d sound as perceived by a 3d being and using a series of normalizations and transforms.

    It was called Frobenius Norm, and was a composition of how a 4-d sound would sound to a 5-d being, I think. I just remember it being "spiffy" and very addictive! :-)

    It was also featured in Woodstockhausen 2000.

    1. Re:Extrapolation for 4d/5d sound by indole · · Score: 2


      Fantastic piece that Frobenius Norm is.

      http://www.sonarplexus.com offers a download of it.

      Now if only he'd come out with another 55 mins of music so I could buy the cd...

      --
      (2,3-Benzopyrrole)
    2. Re:Extrapolation for 4d/5d sound by metlin · · Score: 1

      Yup! That's the one. I remember it being featured in Geisswerks. Extraordinary piece of work!

      Moderators pls mod parent up.

  38. Oh my god! by Jugalator · · Score: 2

    It's full of stars!

    --
    Beware: In C++, your friends can see your privates!
    1. Re:Oh my god! by longbottle · · Score: 1

      LOL! Please dear god, someone mod parent up as funny! Dammit, no mod points... :(

      --
      I don't suffer from insanity. I enjoy every minute of it!
  39. Not a sphere or a line, more like an arc by Ark42 · · Score: 1


    A 3D sphere intersecting a 2D plane would create a circle, but you could only see the circle from a 3D view ontop of the plane.
    If you were on the plain and had no concept of 3D, but still had depth perception, what you would see would be an arc. You could think its a circle, but without going around to the back and making sure the arc follows itself around the entire 360 degrees, you wouldnt know it was complete from just a single viewpoint on the 2D plane.

    1. Re:Not a sphere or a line, more like an arc by Anonymous Coward · · Score: 0

      You must be the lunatic who's calling every ball a hemisphere because you can't see the other half of it.

    2. Re:Not a sphere or a line, more like an arc by _14k4 · · Score: 1

      but still had depth perception I think that's just it. If you're living on a 2d plane, you cannot have depth perception. It reminds me of CAD Diagrams on graph paper for some reason. If depth perception was represented by color (red shift like) then you could tell, but only by infering because of the change in color.

      Then again, IMHO, if you're living on a 2d plane, EVERYTHING is nothing but black. All around you.

    3. Re:Not a sphere or a line, more like an arc by Fred+Ferrigno · · Score: 1

      Ever played Wolfenstein 3D? Despite the name, Wolf 3D is actually 2D world. You can go around objects but not over them. But Wolf 3D still had the illusion of distance and depth perception. Objects far away appear smaller than closer ones. If you had two eyes on the plane, the difference between their linear views could be used to estimate distance, the same as in our world.

      Just look at a frisbee from the side and see if you can still tell it's round.

  40. Re:The answer is yes. by Qbertino · · Score: 2

    Can the human mind gain visualization skills in four dimensional geometry? ... We never see four diminsions. The brain would keep wanting to make one dimension some known continuim such as time, a color sequence, tone, or intensity. Only after this intermediate step would you get a true four dimensional geometry in your head.

    Your actually wrong in the second part. While our senses can't pick up more than 3D Sensory input our brain can very well imagine (and sense) more dimenions. It's simply a matter of training.
    Indian Yogis would call that 'meditation'.

    The stuff those kind of people talk about like "when time becomes irrelevant" and such isn't some mystical BS (at least not with the honorable ones) - it's actually what you expierience when your brain is trained apropriately. Or forced into such condition by (ab)use of drugs.
    You can see "everything happen at once" like one would say. It's interesting that people reaching this kind of 'sense' have a syncronized activity of both halfs of the brain.
    Normaly we don't have that. But Yogis and people who have trained meditation can actually achieve such 'brainsyncing' at will. (a tranquil enviroment given)

    Tibetian meditation 'training' is known to train the same as modern biofeedback 'brainsyncing', often with a nearly identical setup like: "look at those 2 spots and see them as one".

    --
    We suffer more in our imagination than in reality. - Seneca
  41. 3d perception in a 10d universe by Anonymous Coward · · Score: 0

    if a 3d sphere in a 2d perception looks like a circle growing and then shrinking over a long period of time, could time itself be just a approxmiation of objects that have more than just 3 diminsions?
    as in, are we just in a single 3d plane and our perception of time is just things moving through it?
    I don't know enough about hyperspace to properly explain this, is this what hyperspace is about though? /andrew

  42. GPL'ed 3-D Anaglyphics by dav · · Score: 1

    I have some GPL'ed 3-D Anaglyphic code here if anyone wants to play with this sort of 3-D rendering. Of course, you could also use jad to decompile that applet if you feel randy.

  43. yeah but by AndyAMPohl · · Score: 0

    I thought hyperplanes are just 3D slices of data taken from any number of dimensions. So if you have an m x n matrix and want to visualize it, just take 3 of the columns.

  44. I Won't Truly Understand It by Rayonic · · Score: 2

    ... Until someone makes a videogame using these shapes. Maybe something funky like Frequency Cubed, Dance Dance Dance Revolution, or Duke Nukem 4D?

    I'm serious though.

  45. See n-D Space Without any Silly Glasses by AffineTransform · · Score: 1

    High-dimensional (or multivariate) visualization is nothing new in the world of statistics & exploratory data analysis. Check out the freely available XGobi software or the new GGobi package. For a 100% Java version, see Blue Orca.

  46. Heinlein did a better job of explaining by Phoenix-kun · · Score: 1

    Read "And He Built a Crooked House". Heinlein did a bang up job of explaining a hypercube there using toothpicks and clay.

    --
    Phoenix
  47. Welcome to the 4th Dimension by k0tic · · Score: 0

    Don't be fooled--this is not a kaleidoscope! : )

    --
    hell
  48. This... by CoderByBirth · · Score: 1

    "..The bounding hyperplanes can be extended infinitely so that they criss-cross through each other, chopping up hyperspace into many 4-dimensional 'chunks.' Again the inner chunks are finite, and they are distributed in shells around the core polytope."
    ...must the best BOFH "Plausible Excuse" ever!

  49. groan by X_Bones · · Score: 1

    I can't even take this writeup right after waking up, never mind the article itself... it sounds way too much like the timecube guy for me...

  50. Michio Kaku by bobgoatcheese · · Score: 1

    If you're into this sort of thing you should pick up Hyperspace by Michio Kaku, it's a very interesting book that does a pretty good job of explaining multiple dimensions in a way that most can understand.

    --
    How's my typing? Call 1-800-eta-shut
  51. Re: MagicEye in motion... by twoslice · · Score: 1

    Hey guys! It is really a full-motion magicEye and if you squint your eyes it will come into focus -- A resume of Bernard Shifman, in an apparent attempt to spam the 4th dimension.

    --

    From excellent karma to terible karma with a single +5 funny post...
  52. Tic tac toe by tuxedo-steve · · Score: 4, Interesting
    A fun four-dimensional exercise is 4d tic-tac-toe. It's easiest if you build yourself up to it:
    1. Start with your typical 3x3 tic-tac-toe, on a piece of paper.
    2. Now add two more grids. Visualise each grid on top of the one before. It's not difficult to see how this is played. You can get three in a row on a single grid, just like normal. Or you can get three in a row by getting the middle square of each grid (3 in a row, vertically). And so on. This is basically tic-tac-toe in 3D. 3 sets of 3x3 grids. 3x3x3.
    3. Now, add another two sets of three grids. So now you've got 3x3 3x3 grids (still with me?). You can still win just like in the 3x3x3 version. But you've got another 3x3 ways in which to do it. The tricky part is, to visualise each possible `3 in a row', you've got to mentally `rotate in' any one (and only one) 3x3x3 cubic plane.
    Sorry if that's difficult to follow. If you work it through on paper, you'll see what I mean. This is what being bored in math class will lead you to think of, when plain old tic-tac-toe just doesn't seem challenging anymore. :)
    --
    - SMJ - (It's not just a name: it's a bad aftertaste.)
    1. Re:Tic tac toe by Anonymous Coward · · Score: 0

      Who wins
      a) when the first player has to choose the middle field for his first move?
      b) with free first move?

      Solve for dimension d>2.
      Explain your proof.

    2. Re:Tic tac toe by Anonymous Coward · · Score: 0

      Extra points for movie references about d=2.

    3. Re:Tic tac toe by tuxedo-steve · · Score: 1

      Incidentally, I'm currently implementing this as a Java applet.

      --
      - SMJ - (It's not just a name: it's a bad aftertaste.)
  53. Incorrect definition of a hyperplane by dnxthx · · Score: 1

    The correct definition of a hyperplane is here.

  54. what IS hyperspace? by dewhite · · Score: 1

    If you all want to understand hyperspace better you shoud pick up a copy of Michio Kaku's 'Hyperspace'. It covers most of the subject matter of flatland, and goes into more depth on the possibilities of higher dimensional space and unified field theory. It's a really interesting read and speaks on a level that most people can understand. I got alot out of it when I first read the book 6 years ago (I was 14 years old). I didn't get all the mathematics then, but the basic concepts were very well illustrated, and it got me started thinking even then.

    --
    -dewhite
  55. Ouch.. by Mr2cents · · Score: 2, Funny

    Hello flonker,

    Could you please post your telephone number? My lawyer would like to talk to you. I'm off to the hospital, cu guys.

    --
    "It's too bad that stupidity isn't painful." - Anton LaVey
    1. Re:Ouch.. by flonker · · Score: 2

      Yeah, sure, whatever. The important thing is,...

      Can you see the picture now?

    2. Re:Ouch.. by blowhole · · Score: 1

      A sailboat!

      --
      "Ask me about Loom"
    3. Re:Ouch.. by P-Nuts · · Score: 1

      You know what... there is no easter bunny, over there is just a guy in a suit.

  56. Level Curve by Anonymous Coward · · Score: 0

    In calculus, a slice of a higher dimensional shape represented in lower dimesional space is called a level curve. For instance, a level curve of a sphere is a circle. So a sphere is the level curve of a 4th dimensional solid.

  57. interested in applet source code by Anonymous Coward · · Score: 0

    I didn't see any source code --
    If it is available, please say where!
    Just thought I'd mention the interest.

  58. question by coronaride · · Score: 1

    this is all well and good..but a question or two. first of all, isn't it generally agreed that time is the forth dimension? please correct me if i'm wrong, here. therefore, the whole thing about watching the sections transform over the fourth dimension like it's some super fancy function is preposterous! how hard is it to see something change over time? my bottom line is this: it's as easily explained from the second to third dimension as it is from the third to fourth or even seventh to eighth. the author is just relating one dimension to the next dimension up the order. no matter what dimension you stand in, there is going to be one more that you are incapable of seeing higher up. if you treat the fourth dimension like it's something that we have as much control over as the first, second, or third then you will find, eventually, that you are mistaken. finally, your analogy to a 2-d being observing a 3-d object brings up an interesting point. we, as humans, have long realized that while we have control over three dimensions we exist, actually, in many (at least 5, i believe), but are held directly captive by the fourth (which would, in turn, be held captive by the 5th, etc). you say that our brains are hardwired to think in 3 dimensions. is it possible to imagine a purely 2-d existence?

    --
    Those who can, do. Those who can't, go into business for themselves.
  59. 4-D on a 2-D Screen (monitor) by sarcast · · Score: 1

    I recently worked on a project (I am not the author) that modeled 4-D environments on the screen. We made a spaceship that had 4-D elements in it where doors would show or hide based on whether or not the correct hyperplane was in view.

    There is a demo of the software that runs on windows and the navigation is very easy to figure out.

  60. WHEN DO I GET TO SEE THE SAILBOAT?!?!? by Anonymous Coward · · Score: 0

    LOL... Wilhelm

  61. 4th Dimension by ElDuque · · Score: 1

    A few people have posted with a comment about how they consider time to be the fourth dimension.

    Sure, that's one way to think of it, but I think what this animation is attempting to describe is a fourth spatial dimension. That is, describing a geometry where 4 lines can be perpendicular to eachother, instead of the 3 that we are used to.

    Saying the 4th dimension is time is an easy way out.

  62. Fricken Applets! Broken P.O.C. by Anonymous Coward · · Score: 0

    The damned thing does not work. I just get a blank grey screen no matter which button or slider I press or change.

  63. Actually... by cluening · · Score: 2

    Any n-1 dimensional plane cutting through an n dimensional space is a hyperplane. So, the correct wording of the story would have been "A hyper plane is a 3-dimensional space that cuts through a 4-dimensional space, just as a 2-dimensional hyperplane cuts through 3-dimensional space."

    --
    Posted from the wireless couch.
  64. Re:Simple question....spacetime by lugonn · · Score: 1
    I've been reading The Elegant Universe. In it, it says that Einstein started thinking of time as a seperate dimension. As he started trying to figure out how gravity worked, he came to the conclusion that space and time are the same dimension. Time is actually the perception of warped space. The warping is due to gravity being exerted by physical objects, like the sun. So in a sense, time doesn't really exist, it's just in your head.

    Haven't gotten to the M-Theory section yet.

  65. recipe for straaaaange by Tablizer · · Score: 2

    (* If 2D lifeforms did exist (Planiverse suggests they would need zipper-like 2D organ structures) it's quite likely they would have some form of 'depth' perception - along a plane, of course. A sphere intersecting with their world could indeed be recognized as a circle, much like our brains can recognize the depth difference between a ball and a flat disc. *)

    If a 4th dimensional biological entity intersected our dimension, it would probably look really really funky, like a bunch of morphing blobs. Imagine sitting there in a chair watching Bay Watch, and suddenly in the middle of the room small blobs of flesh appear, grow in size, but change shape in really really odd, unnatural ways, then disappear.

    If that wouldn't make your skin crawl off, I don't know what would. It would even be odder than watching obese porn in reverse (not that I recommend it).

    Note that there are some UFO reports of odd blobs appearing, morphing funny, and then just dissappearing. Long shot, I know, but you just never know what may have came our way before.

  66. Obligitory Matrix Joke by Tokerat · · Score: 2

    I COULD see all angles of the scenes at the same time. Of course, time stopped... Sorry.

    --
    CAn'T CompreHend SARcaSm?
  67. more generally by Anonymous Coward · · Score: 0

    Actually, a hyperplane is a subspace of a vector space, with the stipulation that all of the vectors in the subspace have one specific dimension in common (i.e. the same for all of them). A 0D point is a hyperplane of a 1D line, a 1D line is a hyperplane of a 2D plane, ...

    E

  68. Question by Tarquin+Sidebottom · · Score: 1

    If I'm understanding it right... It seems that while it is modelling 4D space, it's stil only displaying 3D at any given time. The question is, can you extend the mathematics of displaying 3D on a 2D screen, to displaying 4D on a (not yet available) 3D holigraphical projector?

  69. Dimensions and Celebrity Deathmatch by black_widow · · Score: 1

    It looked painful when Beavis blew Butthead from 2 dimensions to 3 dimensions on the Celebrity Deathmatch episode...

    If the 4-D glasses are packaged with a fire extinguisher or another compressed air tank with a menacing looking hose (e.g. colonoscopy probe) watch out!

  70. Re:Simple question....spacetime by Anonymous Coward · · Score: 0
    Haven't gotten to the M-Theory section yet.

    Good luck. I've read the book three times and always get hung up on it.