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Big Bang Initial Size

  1. May 22, 2010 #1
    I have not learned of any evidence that would help me decide between these two theories:

    1. The big bang was an explosion of an object smaller than an atom.

    2. The big bang was an explosion of an object larger than a base ball.

    Does our current technology permit us to find such evidence?

    Do you know of any such evidence?

    Thank you for your help

    Jim Adrian
  2. jcsd
  3. May 22, 2010 #2


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    The big bang was not an explosion.
  4. May 23, 2010 #3
    I would suggest you read about BB theory and inflationary cosmology a bit, the internet is full of useful references, including threads here on PF. As nicksauce said, it was not an explosion, so the evidence you're looking for is not extant.
  5. May 23, 2010 #4
    I need to rephrase my question:

    Does our current technology permit us to obtain evidence that the universe was ever smaller than a base ball?

    Do you know of any such evidence?

    Would you briefly describe any such evidence?

    Thank you for your help

    Jim Adrian
    Last edited by a moderator: May 11, 2012
  6. May 23, 2010 #5
    These are matters of theory extrapolated from math, and from observations of an expanding homogeneous universe. You're talking about a BB singularity, something that is not yet described under current theories. I for one, would be curious as to why you're asking this, and how you understand the BB. You said explosion, and that is a fairly huge mistake.
    Last edited by a moderator: May 11, 2012
  7. May 23, 2010 #6
    This answer is helpful and much appreciated.

    For a few years now, I have repeatedly seen on the History Channel one-hour and two hour presentations about the big bang. I have been irritated by what seems to be a number of statements and implications that I cannot infer from the evidence offered in these presentations. This last time, I went on the Internet to find a place like this to ask my unanswered question.

    I am not a physicist.

    When something proves itself important to my business or life, I get some books and maybe take a course and all that stuff; but, I don't investigate that way if there is no compelling reason to do so. One does not investigate a crime without some hint that a crime may have been committed. I may yet become interested in physics enough to make a study of the big bang and all the public talk about it. The way I currently understand the big bang (only from these presentations) is that it was the source of everything we see, and that it was initially very small.

    I appreciate this source of answers and discussion. I have always been able to say 50 words about anything I have seriously studied. I assume there are others who also can do this about physics. You have done this for me.

    Thank you for your answer. There is nothing like a good answer to inspire interest.

    Jim Adrian
    Last edited: May 23, 2010
  8. May 23, 2010 #7

    Your question of the initial "size" of the universe is a interesting one. "Size" as we know it is the spatial distance between two point. Now how we measure that distance is with a standard. In daily life, we use a ruler. In the space time, we use a metric. The metric of the modern universe, far from intense gravitation sources is nearly flat: one meter here is one meter there. In the early universe, there was extreme curvature of the metric. So to define a distance at creation is almost pointless (sorry for the obvious pun). The universe, as best we can determine began as a singularity. The evidence points to period shortly after the initial creation of rapid expansion that flatted out the universe, removing nearly all curvature from the universe (known as the inflation phase), making the universe safe for rulers.

    Hope that helps.

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