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Is it wrong to see the bang as insertion of space?

  1. Apr 2, 2013 #1
    Picturing the bang as an increasing presence of space between bits of energy, would be a kind of inside-out view from a picture of expanding mass energy. My first impression is that the two ideas seem equivalent, but suggest different inferences.
    i find Peacock commenting in Cosmological Physics, re common misconceptions: http://ned.ipac.caltech.edu/level5/Peacock/frames.html
    "...a common question asked by laymen and some physicists is what the universe expands into. The very terminology of the ``big bang'' suggests an explosion, which flings debris out into some void. Such a picture is strongly suggested by many semi-popular descriptions, which commonly include a description of the initial instant as one ``where all the matter in the universe is gathered at a single point'', or something to that effect. This phrase can probably be traced back to Lemaître's unfortunate term ``the primaeval atom''. Describing the origin of the expansion as an explosion is probably not a good idea in any case; it suggests some input of energy that moves matter from an initial state of rest. Classically, this is false: the expansion merely appears as an initial condition....it is one of the advantages of inflationary cosmology that it supplies an explicit mechanism for starting the expansion: the repulsive effect of vacuum energy..."
    This book was published in 1999, i think, and it appears Peacock is not looking at dark energy, which is suspected also of being a feature of vacuum energy or at least of space, and unless i'm off, this would not be considered an "initial condition."
    i assume i should consider that the nearest galaxies that are receding at Hubble rate are doing so as a result of the impetus of initial inflation/conflation, and not large scale expansion of space, and that the cosmological constant is due to a less initial vacuum energy.
    But to me the initial condition still looks like one of creation of space, between bits of energy. So inflation and accelerating expansion over time both look to me just like the creation of space. But the message i'm getting is that in the start vacuum imparts kinetic energy and later it expands space?
    Testing a definition of space as, "anywhere a particle can go," over time QM provides that particles can go more and more places. To me, this looks like the creation of space. i.e. particles create new places they can go, over time, and in this way create space. [trick definition?] i think current consensus is that space-time creates particle, i see energy in time creating space.
    i feel out of step here, i need counseling, intervention, and probably tough love, but i want to know the truth as we now it, and soon.
    Thx in advance for your kind attention,
    Last edited: Apr 2, 2013
  2. jcsd
  3. Apr 2, 2013 #2
    First off expansion is not the result of a singularity explosion.

    A good visualizer of expansion include Balloon analogy or raisin bread analogy. Keep in mind analogies can lead to confusion. as there is no inside or outside of the balloon surface.

    My preferred analogy is grids. Imagine a grid of squares each vertical and horizontal crossing of the grid lines is a coordinate. As space expands all distances between coordinates vertical, horizontal and diagonal increase equally. So the statement space expands between points is valid.

    The sticky thread above has some good coverage on the balloon analogy.

    there is several theories as to how this works so I will lead you to the roots of the inflationary model. This is the false vacuum model which originated with A.Guth. If you google false vacuum you will easily find some decent articles on this process.
    There are more current inflationary models such as eternal inflationary model, however they all derive from the false vacuum model. The virtual particle creation described by false vacuum is a form of Parker radiation. However start with flse vacuum before examining parker radiation. I found doing so in that order is easier to understand
    Last edited: Apr 2, 2013
  4. Apr 2, 2013 #3
    In the spirit of comiseration, Mordred, you said in part, "...A good visualizer of expansion include Balloon analogy or raisin bread analogy. Keep in mind analogies can lead to confusion...."
    Yes, looking at the beach ball's surface as an analogy for a closed universe, if you saw the stuff that turned into the local and current Milky Way coming back at you from over the horizon, doesn't it seem like it would be blue shifted? It's speeding away in one direction, but when it comes around, it should be coming at you at roughly about as fast as you saw it disapear over the horizon in the other direction.
    Now i buy my beachballs at Walmart, so they aren't the fancy dancy new ones. Just sayin'.
  5. Apr 2, 2013 #4
    Yeah the ballon analogy itself is full of problems hence why I prefer the grid line analogy
  6. Apr 2, 2013 #5
    My wife, always tolerant, became ever more appreciative after our youngest moved out at age 28. Living in a contested space was messing up the mood for everbody. Too much competition for a limited amount of monkey bars, not to mention how finicky multiple residents can be about their Monkey Chow.
    The strain was obvious by its absence when the stress was removed.
  7. Apr 2, 2013 #6
    lol you evidently looked at my signature, I hear ya on the room issue life is great now that the kids are out on their own. My wife still doesn't understand why I study this universe stuff as she says i'll never go there lol. Good thing I don't tell her about my QM studies. I don't believe she even understands what quantum mechanics is lol
  8. Apr 2, 2013 #7


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    Is the grid line analogy similar to my favorite, Escher's Infinite Lattice?


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  9. Apr 2, 2013 #8
    lol yeah though my quick descriptive above is a 2 dimensional whic is more accurate as a 3 dimensional
  10. Apr 2, 2013 #9
    Mordred: "...doesn't understand why I study this universe stuff ..."
    i'm attracted to the idea of a relatively exact science approaching a question for which there is likely no answer; and at the other end, at 60 i realized i didn't know what i was made of, and that nearly every thing but Higg's had been worked out by the Standard Particle Model. So it was a good time to finally find out. However, it became necessary to understand QM better to really understand what was being said about our bitty bits.
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