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Common miscons (e.g. it exploded from a singularity) &why to check FAQ

  1. Apr 18, 2013 #1

    marcus

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    This is an idea for a thread. Might work or might not. Each post here should address a common misconception in 25 words or less.

    You don't have to restate the common misconception, just respond to it. I think we're all familiar with the main ones that keep coming up. Your post (if you contribute one) could motivate a puzzled newcomer to consult the FAQ for lengthier discussion.
     
    Last edited: Apr 18, 2013
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  3. Apr 18, 2013 #2

    marcus

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    A singularity is not thought of as a real thing in nature

    Singularity means glitch or breakdown in a math theory. Not a thing in nature.
    A symptom that the equations need fixing.
     
  4. Apr 18, 2013 #3

    marcus

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    No evidence that time stops if you go back to start of expansion. Depends on which model. In some, it continues on back before expansion.
     
  5. Apr 18, 2013 #4

    marcus

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    The currently observable portion of the universe is not the same as the universe ( the whole thing, which might be infinite, or might not.) Consult FAQ.
     
  6. Apr 18, 2013 #5

    marcus

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    No reason to think universe surrounded by empty space. It doesn't need empty space to expand into. No reason to imagine an edge. Consult FAQ.
     
  7. Apr 18, 2013 #6

    marcus

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    Universe may have been infinite at start of expansion. If finite size we don't yet have an estimate. AFAWK expansion isn't outwards from a point.
     
  8. Apr 18, 2013 #7
    Time does not stop inside an event horizon. To an outside observer it does but not for an observer inside it moves normally
     
    Last edited: Apr 18, 2013
  9. Apr 18, 2013 #8
    hawkings radiation occurs outside an EH and is not faster than light
     
  10. Apr 18, 2013 #9
    Which models? Please mention some names.
     
  11. Apr 18, 2013 #10

    marcus

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    All of the first 50 papers on this keyword search list of research literature are about that kind of model:
    http://inspirehep.net/search?ln=en&...2y=2013&sf=&so=a&rm=citation&rg=50&sc=0&of=hb

    Probably the majority of the 400 or so other papers are too, but I didn't scan the list beyond the first 100. Research with models that match the observation data as well as the classic model but go back further in time has gotten very active. These are paper just since 2009.

    We need a convention that if you have a question or want to discuss you start a new thread so this one can stay focused.
     
    Last edited: Apr 18, 2013
  12. Apr 19, 2013 #11
    Hubble red shift relationship did not prove the big bang. Hoyle's model was developed after Hubbles's observaitons and was compatible with it. If I had to pick one obervation that showed the big bang (phase not singulatiry) then I would not pick Hubble. I think I would pick the fact the CMb is a near perfect balck body. If COBe had found it was not a black body that might have really thrown the cat amongst the pigeons.
     
  13. Apr 20, 2013 #12
    If the universe started out, or was ever at a finite size, then it must be of a finite size forever, yes?
     
  14. Apr 20, 2013 #13
    yes a finite cannot become infinite.

    back to misconceptions. The word nothing has special meaning in physics. Quantum effects occur in regions often described as "nothing".
     
  15. Apr 21, 2013 #14
    To add a related one-liner:

    "The steady state universe model isn't the same thing as a static universe"
     
  16. Apr 21, 2013 #15
    Yes I think thats a nice way to sum it up.
     
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