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Creation of matter

  1. Jul 24, 2010 #1
    This has puzzled me for a very long time. I know the theory that the universe was created from a big bang, but this means that all the matter in the universe existed in a different form before that. Be it gas or some other weird substance, it still existed. So how can all this substance appear from nothing? I cannot see how it possibly could, so the answer must be that all matter has just existed for an infinite time. This answer puzzles me too and leads me to the conclusion that the human brain simply cannot comprehend the big picture at all, including space, time and motion. I believe time is a factor in the mystery somewhere along the line, and we do not understand it at all. Any ideas as to how something was created out of nothing? Thanks for reading this.
  2. jcsd
  3. Jul 24, 2010 #2
    1. Any form of matter could not exist BEFORE the Big Bang, because before the Big Bang there was no TIME. At least, in its current form.
    2. Time is not infinite. This is a key to understand the Big Bang. It was not an explosion somewhere at some time.
    3. Energy and matter is not conserved in Cosmology (surprise!) - this subject is lengthy...
  4. Jul 24, 2010 #3
    BB theory does not state that there could not exist any form of matter before the Big Bang.

    Read into inflationary cosmology.

    Conservation of matter/energy is valid in cosmology also. Why do you think otherwise?
  5. Jul 25, 2010 #4


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    Not really. Read this for more:

    The basic, basic idea is that General Relativity doesn't conserve energy, but instead conserves the stress-energy tensor, an object which includes energy, momentum, pressure, and stress. Conservation of the entire stress-energy tensor, under many circumstances, forces some of the components of said tensor to not be conserved, including energy.

    For example, photons experience pressure equal to one third their energy density in each direction. Because of this, conservation of the stress-energy tensor makes it so that in an expanding universe, an expanding volume of photons loses energy with time (we see this as the redshift).

    Furthermore, there wasn't any matter around at all during inflation. The matter was produced out of the exceedingly hot thermal bath that was produced as inflation ended, a temperature which was high enough for the balance between matter and anti-matter to be upset, allowing some small amount of matter to survive annihilation as our universe cooled.
  6. Jul 25, 2010 #5
    yeah, me too. But I think the human brain can comprehend it. you're just not thinking about it right. Phenomena in our Universe are not continuous but exhibit jump-discontinuities, catastrophes in fact. You know this, the straw that breaks the camel's back. Often these catastrophes result in qualitatively different phenomena: a single snapping bolt on a bridge causes the qualitatively different phenomena of a pile of rubble, gas entering a room with a lit match reaches a critical concentration and suddenly and qualitatively changes to an explosion.

    I've personally grown convinced that is how the Universe emerged, through a catastrophe of some larger system and what we observe now in the Universe, the matter, energy, time, even the physics, is qualitatively different than what existed before the Big Bang so I do not believe it is correct to suppose anything in our Universe, the matter for example, "existed" before the Big Bang. Even the very word "exist" may very well not have meaning in that epoch.

    Some may argue the pile of rubble on the ground is still metal but the concept of "bridge" looses meaning at the catastrophe point of collapse in the same way perhaps the concept of "matter" may lose meaning at the catastrophe of the Big Bang.

    I don't know, perhaps this is against forum rules. It's my personal believe however in defense of that believe, it does fit with observation: look around you, the world is filled with jump-discontinuities from fission/fusion to super nova. Why wouldn't the whole Universe act the same way?
    Last edited: Jul 25, 2010
  7. Jul 25, 2010 #6
    You don't know that. And the Big bang Theory does not explicate that such was the case. Instead of thinking that the Big bang was the event of 'creation' you should reflect on this theory more in the sense of how the universe evolved from a previous, partly unknown, state.
  8. Jul 25, 2010 #7
    This was one of the ideas, the idea of a phase change of matter, as the birth of the universe, that lead into the theory of cosmic inflation. Btw. that whole idea, which proved succesfull, originated in the Soviet Union by the soviet cosmologist Starobinsky.
  9. Jul 25, 2010 #8

    What I wrote is my idea from scratch. Didn't take it from anyone but I don't mind if others are thinking that way too as I believe in it.
    Last edited: Jul 25, 2010
  10. Jul 25, 2010 #9
    Starobinsky came up with the idea end 70-ies and early 80-ies Allan Guth more-or-less reinvented the idea and labelled it 'inflation'.
  11. Jul 25, 2010 #10
    Ok then. That's before me. Didn't realize inflation was a theory of catastrophe or "phase-transition" but can't say I'm very familiar with modern Cosmology.
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