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Big bang related questions

  1. Apr 27, 2005 #1
    I agree with the idea that a big bang was a singularity of matter, which burst into all matter that we know, and that the universe is expanding-galaxies are drifting apart.

    What is the common understanding of what was before this singularity. I can only deduce that it was another universe, with the "expanding and then contracting onto itself" idea of universe formation. So therefore, the universe is infinite because it will constantly be re developed. But how does one have infinity, i understand you cannot see the end because it has not happened yet but how could you have an undefined beginning :uhh:.

    there is a center to the solar system, and our galaxy, is there a center of the universe?

    Is the universe infinite and why does a galaxy appear to look two dimensional whereas a cluster of them is 3d.
  2. jcsd
  3. Apr 27, 2005 #2

    James R

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    Some theories say there was no "before". Time started at the big bang. The big bang was not like an ordinary explosion in space. It was an explosion OF space, and time as well.

    The universe has no centre. The big bang occurred everywhere at once. Remember, it was not an explosion in a pre-existing space, but an explosion OF space. The space between galaxies is currently expanding, so every galaxy moves away from every other galaxy, and there is no centre of expansion.
  4. Apr 27, 2005 #3
    I'm led to believe that the answer is definitely maybe! Noone knows for sure if the universe is open (infinite) or closed (finite), and the accepted theories allow for either. (but don't trust me on this...)

    What do you mean?
    Do you mean they look two dimensional because photographs are two dimensional?

    Or that they always seem to be flat disks?

    http://www.seds.org/messier/m/m104.html" [Broken]
    Last edited by a moderator: May 2, 2017
  5. Apr 28, 2005 #4
    2d as in protostar disk resembling galaxies, planets are spheroidal... :confused:.

    Relativity says space exploded? I was under the impression that all matter was compressed into a singularity until it detonated sending matter out into space.

    Either way, sense some form of intelligence behind the events. If there was nothing, why would something come of it? There must be some explainable impetus behind the event.
  6. Apr 28, 2005 #5


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    1. It is generally accepted that space is expanding even now, as it has from the first second (when space inflated very rapidly). It is this inflation that primarily accounts for the distribution of matter in the universe, and not the "explosive" nature of the BB itself (i.e. not because everything was so hot). As to what is causing the inflation - i.e. the details of the physics - this is still a bit hazy. It is consistent with some models of General Relativity.

    2. What good does postulating intelligence do? Suppose we are a lab experiment in some 26 dimensional super-universe. Everyone there would seem like a god to us. But who created them? There are some questions we will never know the answer to.
  7. Apr 28, 2005 #6
    oldunion and others -

    One of the best books I've read of late on the issues regarding the early universe, and on the thinking and people doing the thinking about it, is Alan Guth's "The Inlfatinary Universe" (1997).

    Dr. Guth, one of (and in some ways THE) individuals who put forth the inflationary aspect of the early universe, does a superb job at explaining, without detailing the mathematics, these ideas about how things may have gotten started.

    Dr. Guth is often quoted as saying that the universe may be the "ultimate free lunch" in that the there is much to suggest from his work and that of others that the emergence of everything we observe from 'nothing' is not such an impossible thing.
  8. Apr 28, 2005 #7
    Which is why im going to live forever, so i will know in the end.

    And ill definately read the book frank, after i finish up with einsteins dreams.
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