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3D Pixels

  1. Apr 2, 2009 #1
    Okay, first of all I'm not a physicist, but I am a mathematician and programmer.
    I've been working on a computer game recently and its got me thinking about physics :)

    I'm hoping someone here will be able to point me at a theory that encompasses what I've been thinking about, or reasons why its nonsense...

    From what I've picked up in the very informal physics education I've had, most if not all physical theories of 3d space seem to be based on the model of a void partially filled with stuff that moves around in it.
    What evidence is there to suggest that it isn't a solid space made of 3d "pixels" that have a number of different properties. So instead of something moving from A to B, the properties at pixel A are reset and the properties of B become what was at A. In case thats not clear - think of a white dot moving one pixel to the right on your otherwise black computer screen. It appears that the dot has moved, but in fact the original pixel has turned black and the destination pixel has turned white.

    Any feedback greatly appreciated :)

    For info, I am intending to study physics properly soon
  2. jcsd
  3. Apr 4, 2009 #2
    I think it is generally accepted that there really isn't any 'void'. That even free space has a certain amount of energy even when there is no matter present. The energy is a result of 'virtual particles' popping into and out of existence. The virtual particles are inferred from Heisenberg's uncertainty principle. The principle says that there is a theoretical limit to the knowledge you can have of energy and time simultaneously. With regards to position and momentum(on which there is a similar limit) this fact was interpreted as evidence that a particle really does not have an exact position and momentum. And it's not just that we don't know these quantities, nature doesn't know them. So, because this must also apply to energy and time, you can't have precisely zero energy anywhere, even in a vacuum. There must be quantum fluctuations in energy. These fluctuations are interpreted as virtual particles. This all seems like nonsense but I think this energy has been detected. It was called the Casimir effect.

    It seems like the idea that there is no void would prove that motion is impossible. Things would'nt have anywhere to go. Perhaps an infinite space would fix this problem. Or perhaps, like you said, this would'nt matter because what we have is not motion at all, but just the propagation of change in the characteristics of particular points in space. Like a change in color of particular pixels to simulate an object moving across the screen.
  4. Apr 4, 2009 #3


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    Then you need to explain the presence of momentum. A "moving pixel" on your computer screen carries no momentum. A moving object does.

  5. Apr 4, 2009 #4
    3d pixels are called 'voxels', you may want to look that up learn about them. Your black and white pixel example is a bit confusing to me, but consider the model of electrical current where electrons occupy 'holes' and the electrons move from one hole to the next. There is clearly a momentum experienced by the electrons. Remember, one hole cannot be filled unless the electron moves from an adjacent hole and something must cause this movement. This something is a force carrier, also called a boson and in the case of the electron the force carrier is a photon.
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