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Please answer a layman's questions about the Big Bang

  1. Aug 3, 2009 #1
    I know nothing about astronomy, (but I find it very interesting) so, here it goes:

    1-If you look at the sky, is there an exact location of the Big Bang? If so, where should one look at? Or is the BB more like space being created between the planets?
    -If the first one, Shouldn't that place of the sky be more full of light? (showing the light of the stars that were there before, or something?) Shouldn't it be like a cluster of things? Shouldn't it be more darkness towards the opposite direction. Are there any ideas of what should one find if he would go in that direction (towards the BB)?

    2-Does the fact that it is still expanding should mean that it is still producing time and matter?
    3-Could there be more elements (types of atoms) out there in the space? Could there be more elements in the future if the BB is still generating matter?
    4-Is it the very same expansion of the universe, the one that generates the energy that gives us the forces in F=m.a? Could there be any other source for the energy that generate those forces?
    5-Isn't kind of weird/silly the name "Big Bang"? Could there be sound at the time?
    6-Did discrete particles had the same size at the moment of the BB as they do now?
  2. jcsd
  3. Aug 3, 2009 #2


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    Hello there!

    1: No, there is no "exact location" you can point to and say the big bang happened here. For a question like this it is useful to think of the balloon analogy of the big bang. Imagine a balloon with a bunch of dots drawn on it. If the balloon is blown up, you have a picture of our current universe, with our galaxy being one of the dots. Imagine running the clock backwards as the balloon was blown up. All the dots get closet and closer together, and in the case of a perfect balloon, they all come together as the balloon shrinks to zero size at all. This is rather what the situation is like for our own universe. In a sense, the big bang happened everywhere. Refer to the sticky thread "An effort to get us all on the same page" in the Cosmology forum if this is a bit confusing.

    2: No. This doesn't make any sense.

    3: No, not really. The fact that we observe ~92 elements in nature is a result of the fact that the other chemical elements are unstable and decay quickly. The highest elements on the periodic table have been created in labs for only tiny fractions of a second, so any production in nature would instantly be reversed by decay. In general, the higher the atomic number (larger the atom) the more unstable it is. However, there is a theoretically predicted "island of stability" around Z=120 where it is possible that these elements could exist for anywhere from minutes and hours to billions of years.

    4: No. The expansion of the universe and Newton's second law are completely separate concepts. In the case of the expansion of the universe, there is no force necessary. We are simply coasting along on the push we got at the beginning (ignoring dark energy).

    5: Yes, it is a weird and silly name, and was actually coined by an opponent of the theory in order to discredit it! Of course, the depiction one might see on a NOVA special of a giant explosion with brilliant light and colours is wholly inaccurate. Light couldn't even move freely until about 300,000 years after the bang happened!

    6: What do you mean by discrete particles? Do you mean fundamental particles such as quarks and electrons? If so, I'm pretty sure these are postulated to be points according to the generally accepted theories.

    I realize I glossed over a lot of concepts in my explanations that you might not get so feel free to ask for clarification.
  4. Aug 3, 2009 #3
    Thanks!!! It has been very helpfull!!!!!!!!!!!!!
    I understand most of the things you said, except I know have a few new questions:
    -If we are simply "coasting along on the push we got at the beginning", shouldn't it be a space to support the expansion? Doesn't that need to be created? I mean, don't things exist in space/time? Doesn't space/time cames from the BB? Doesn't the very expansion implies more time/space in between the matter? Doesn't it implies more creation happening?

    Also, yes I meant fundamental particles. Thanks, I reckon now that it was a silly question, I was just testing my own philosophies with what QM said.
  5. Aug 7, 2009 #4
    Can someone answer this last question (in bold)?
  6. Aug 7, 2009 #5
    You're quite right and Nabeshin is mistaken. Space-time is doing all the expanding - work against the gravitational potential of the mass contained within. But the expansion, at a local level, is overwhelmed by the gravity of stars and planets so it, in theory, isn't noticeable except between distant galaxies not held together by local gravity. But there's signs that maybe gravity has other ideas - the Pioneer Anomaly and the flat rotation curve of the Galaxy are two possible lines of evidence for something odd going on with gravity.
  7. Aug 7, 2009 #6


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    "Spacetime doing work against potential" doesn't sound like a mainstream concept.
  8. Aug 7, 2009 #7


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    I'm pretty sure the explanation I posted is a representation of the standard, non-DE model of universal expansion.

    I'm not really sure I understand your question, the wording seems a little.. confused. Let me say this: One way of looking at the expansion of the universe is that space between two distant points is being created. Therefore, two distant galaxies aren't exactly moving away from each other, there is simply more space being created in between them. In this sense you can say there is a creation of space, but the extension of this to creation of time seems odd. Certainly if you favor this interpretation, space is being created, but this does not imply that matter is being created.

    The first part of your question about space supporting the expansion seems like gibberish to me... I have no idea what you're talking about... Perhaps you can try to rephrase?
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