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Issues regarding the expansion of the Universe at the subatomic level

  1. Mar 30, 2012 #1
    Sorry for my bad English and mostly for my bad Physics.
    For me it doesn't make any sense regarding the expansion of the Universe as a distant process, a sort of time&space machine which 'degulfs' more room for the known things to occupy. My guess is the expansion is happening here now at a subatomic level and it swells matter, distancing the quarks from each other within the hadron, forcing gluons to attempt linking their more and more distant quarks (and having this confinement condition as a safety measure against proton disintegration).
    This could mean that the age of the Universe could be measured according to the distance between quarks. If space-time fabric has the structure of a net, its constant number of nodes get farther from each other and the ridges get longer, so the speed of light is a constant if measured by nodes but a variable if we measure the real distance it covers per time unit. Moreover, if a proton indicates the distance in time from the Big Bang by its size, maybe if one could shrink a proton to a previous size, it will necessarily transpose itself in that past moment when all the protons had this size. It's like the standard meter from Paris is getting longer each split-second. This also could lead to a critical moment when protons will break at an exponential rate and all the matter in the Universe will be shred by the tension of the space-time mesh.
    How am I wrong here? I guess I must be awfully wrong, given my poor knowledge (which is hardly past the high school level and some books for dummies).
  2. jcsd
  3. Mar 30, 2012 #2


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    I'm fairly certain that the other fundamental forces are enough to nullify expansion. So the Earth doesn't get further from the sun due to gravity holding them together and atoms in molecules don't get further away due to electromagnetic interaction.

    Hopefully an expert will wander by to confirm this.
  4. Mar 30, 2012 #3
    This is right. Gravitationally bound systems overcome the force of expansion on the local scale. (Local planetary systems, star systems, galaxies and clusters.) On the large scale expansion wins out but on the small scale gravity is king.
  5. Apr 3, 2012 #4

    i like this..

    i often feel looking in rather than out is the way
  6. Apr 3, 2012 #5


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    The "dark energy" that causes the expansion of the universe is VERY weak on small scales and systems such as atoms and galaxies that are bound by strong/weak/gravity forces are NOT affected by it.

    It is like an ant pushing on a house. You might think that it has a tiny effect that could add up over time, but that is not correct. It has NO effect.

    On REALLY LARGE scales (billions of light years of distance) the cumulative effect of dark energy has a large effect.
  7. Apr 3, 2012 #6


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    The way to where/what? We cannot observe expansion at the subatomic scale. Period. So we learn nothing about it by doing so. Similarly we didn't learn about gravity by looking at the subatomic scale because, like expansion, the other forces are many many orders of magnitude stronger at that scale.
  8. Apr 6, 2012 #7
    I guess we did, because it happens in black holes and armies of physicists try to 'look' for the gravity at the subatomic scale.
    And, if I'm not wrong, the main purpose of CERN these days is exactly to probe gravity at small scales.
  9. Apr 6, 2012 #8
    We do observer expansion from the subatomic scale how else do you explain light? :confused:
  10. Apr 6, 2012 #9


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    What they mean is that the expansion of the universe does not take place on small scales. Distances between subatomic particles are not increasing. It's only on scales of galaxy clusters and larger that objects are moving away from each other.

    Your question about light is a bit too vague for me to address.
  11. Apr 6, 2012 #10


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    We are trying to learn about gravity at that scale now, but our current and previous main theories on gravitation did not. (GR and Newtonian)

    I don't believe so. CERN has multiple experiments running, one of the main is the LHC, who's "main" purpose is searching for new particles such as the higgs and trying to understand why antimatter is so much less dominant than normal matter in the universe. If quantum gravity is involved I doubt that it is its "main" purpose.
  12. Apr 17, 2012 #11
    A photon even when thought of as a packet of energy is subatomic, and when we measure it as "longer" we think of space expanding because the photon is older. This is a measure of distances between subatomic particles increasing. :confused:
  13. Apr 17, 2012 #12


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    We can measure red-shifts of distant galaxies. And such galactic red-shifts are caused by the wave crests (and troughs) slowly spreading apart, due to expansion, as the light wave traveled through the gradually expanding cosmos. This cosmic expansion has the effect of increasing a photon's wavelength. So yes, that's kind of on a microscopic scale. But I would not say that it is due to the distance between subatomic particles increasing. The crests and troughs of a given photon are not individual particles.

    But particles that are interacting due to other forces (such as in the case of solids, liquids, solar systems, etc.) are overwhelmed by the other forces compared to whatever force is causing [edit: accelerated] expansion.

    For example, take a meter stick and place one hand near each end and try to pull it apart. Give it a good yank, and try to stretch the meter stick making it longer. If you're only using your hands and arms, it probably won't budge. What's keeping it together? Essentially, it's the electromagnetic force in this case (it also involves the minutia of atomic bonds between atoms and molecules, but these bonds are ultimately a manifestation of the electromagnetic force, is my point). Pull on that meter stick until you're 100 years old, and it's not going to make a difference. Find a way to keep it up for 10 billion years and that meter stick still won't pull apart (ignoring things like corrosion, fire, natural disasters, etc.)

    The force you're applying with your arms is many, many orders of magnitude greater than the cosmic expansion force acting on that meter stick. So if you are not able to increase the length of the meter stick (with your hands and arms), the expansive force certainly won't either.
    Last edited: Apr 17, 2012
  14. Apr 17, 2012 #13
    I strongly agree with you. Its so weak that the expansion is termed by a fraction of 1 followed by 100 zeros. If its anything less than that, then our universe will shrink away and anything greater causes the disappearance of universe within seconds. Its constant. But, the wonder here is that Even though the expansion rate is constant, the universe expansion is not slowing down. In fact, its accelerating towards its edges. That led to the theory of Inflation.

    You are right bro. Gravity is never, of course negiligibly, effected by the dark energy. It only pushes one part of matter away from another unlike gravity, but doesn't break the fundamental part of the matter. I am not sure on this, because its not yet experimented or theorized to full extent. Super symmetry theory discusses this better
  15. Apr 20, 2012 #14


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    Prior to the bolded part, you are referring to the accelerated expansion of the universe. Inflation is a totally different thing ... something that happened in a very early and very tiny fraction of the first second after the singularity.
  16. Apr 20, 2012 #15
    I don't think so. I read that Inflation theory is also extended to explain the concept of ever accelerating universe. Look at wikipedia to avoid confusions. I don't think wikipedia can get confused like me. I watched a documentary (The Fabric of Cosmos), which said the same. Check it out.
  17. Apr 20, 2012 #16


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    Wiki agrees w/ me:

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