Slashdot Mirror


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."

2 of 214 comments (clear)

  1. 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.

  2. 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