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Multiple collections of energy, very far apart

  1. Jun 7, 2012 #1
    Is it possible that the big bang, and all the energy we know of in the universe, is just one big collection of energy of many? Is it possible that big bangs are happening all the time, but just so vastly far apart that we could never detect them?

    This seems to get into the "Could anything exist outside of the big bang?" question, to which I'm told the answer is "no" because there WAS no outside of the big bang, which is still confusing to me.

    Is the idea that the big bang truly encompasses absolutely everything in the entire universe, including the universe itself?

    Help, please. And thank you.
  2. jcsd
  3. Jun 7, 2012 #2
    Well, we don't know. We have absolutely no (factual) idea regarding what happened at t=0. The big bang model is more of an 'after the bang' model. We know the universe was extremely hot, and extremely dense, and expanded rapidly. What happened before that? As I said, we don't know. It's pure speculation.

    To add: If you are wondering about 'multiverse' scenarios, you should read Tegmark's article. If that's what you're interested in, I'd recommend reading over the innumerable amount of threads regarding it. As you will notice, any discussion that involves any talk of a multiverse devolves pretty quickly into nothing useful.
  4. Jun 7, 2012 #3


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    What definition of energy are you using here?

    According to our current understanding of the early universe and what the big bang was, I don't believe so. To my knowledge the big bang was not an explosion in space, it actually isn't even a real event at all, but a name made up in an attempt to discredit the initial theory. The Big Bang theory as it is commonly called simply states that the very very early universe was much hotter and much denser than it is now. It expanded from there and has been expanding since. It doesn't say there was a giant explosion or anything else about where the universe came from.

    I would guess that you are imagining this large explosion in space that everything expanded outward from. This is incorrect. As I said above the universe, ALL of it, everything within it, was simply much closer together about 14 billion years ago. So close that the density of the universe was exceedingly high, driving the temperature up to phenomenal levels as well. The entire universe existed as an extremely hot plasma where light created matter and antimatter which then annihilated with itself to create light, with the cycle repeating over and over. Luckily for us the universe wasn't static, it was expanding. And as the universe expanded it cooled off until the matter-antimatter created ceased. At this point something weird happens that we are still investigating. For some reason, when the final matter-antimatter pairs annihilated there was still matter left over. Enough matter to create everything we see in the universe today. That means that somehow matter was created in slightly larger amounts than antimatter, the exact reasons we don't know yet.
  5. Jun 8, 2012 #4
    Thanks very much for the replies.

    So basically, we don't know and can't talk without wild speculation about what happened before, or outside of, the big bang? That's what I think I'm hearing here.

    Why do we think that the big bang encompassed everything, instead of just everything in the known universe?
  6. Jun 8, 2012 #5


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    Pretty much.

    Given what we know about the early universe there isn't any reason to believe that any part of the universe is different from our observable one in terms of how it evolved from it's earlier state or what it was like 14 billion years ago.
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