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Theories on Dimensions/Time Quantized?

  1. Jun 23, 2011 #1
    I wasn't sure what category to put this in or if the proceeding questions are established theory so I decided to put it in "Beyond the Standard Model."

    Is there evidence to suggest that a length can only be so small or that all lengths are infinitely divisible?

    Is there evidence to suggest that time is continuous or that it exists only in discrete frames?

  2. jcsd
  3. Jun 23, 2011 #2
    Myself, I believe that lengths are infinitely divisible simply because I can't imagine a object so small that you can't split/divide it. Even if we (humans) cannot divide it in a experiment, the object still exists and has mass. Even if it was 1000's of times smaller than a proton, emphasis on 'if it was', I believe that you could always, theoretically divide it. I simply can't imagine not being able to divide something even if we don't have the technology to do so. Also, I can't imagine a particle that is made up of nothing except itself - if that makes sense.

    What do you mean by, is time continuous?
  4. Jun 23, 2011 #3
    I mean, are moments in time infinitely divisble or does change occur in discrete frames, analgous to the way that light have bundled energy quanta.
  5. Jun 24, 2011 #4
    what do you think?
  6. Jun 24, 2011 #5


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    There is currently absolutely no evidence to suggest that space and time are anything but continuous.

    Theoretically, people often talk about the planck length and planck time being the smallest meaningful units of space and time. This is, however, more a statement about our lack of knowledge than any deep truth about the universe. Essentially, the planck scale simply tells us when our currently decoupled theories of quantum mechanics and gravity will need to be unified in order to get a correct picture of reality.
  7. Jun 24, 2011 #6


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    Fundamental particles have distinct "sizes" that are quantized in a way if you will. You cannot ever divide them into anything. But we are talking about spacetime, not matter. As has been said above, we have no reason to believe that time or space is quantized.
  8. Jun 24, 2011 #7
    But even if you had the smallest particle, wouldn't you be able to accelerate them to high speeds and collide with each other so they split up, like we do with protons?
  9. Jun 24, 2011 #8


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    No, as the particles do not split up. Lets look at electrons since protons are not fundamental particles but are composite particles made up of quarks. When two electrons are collided at high speeds they create a number of particles. The key here is that they can create particles that are MORE massive than they are! It's like crashing your car into a brick wall at 99% the speed of light and having 5 buses appear from the wreckage! The particles were not part of the electrons to begin with, they were created from the kinetic energy of the two electrons. To the very best of our knowledge Electrons, Photons, Quarks, and various other particles ARE fundamental. IE they are not made up of smaller less massive particles.
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