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True Age of The Universe

  1. Aug 17, 2006 #1
    Is there any true way to age the universe? i mean, i've done some research on this, and from several points of data, i can honestly say no. look at gravitational lensing for example. unless you're like a master at picking out what is a mirror image or something, you're already messed up, but i would also have to say that wouldn't gravitational lensing also move the location and the distance of a star or galaxy millions of light years off course? also, with such a problem, we can also only seen 'accurately' a couple hundred lightyears. after that the gravitational lensing messes everything up in their locations and distances.

    not only this, but does Gravitational lensing have any effect on the 'color' of the light reflected from stars? another thing, without knowing the exact 'size' of the explosion of the big bang, we therefore cannot determine the amount of accelleration from the beginning point of the explosion, plus we don't even know where this explosion occured. not only that, but with such a huge explosion wouldn't there be a very large time dilation factor? with that said, would that not allow stars to travel thousands of light years with a very large explosion, time dilation taking place on a major scale, thus causing the stars to seem to have stopped while the explosion is yet still occuring this very second, but has been slowed down at extreme proportions?

    just a question guys, i just want to hear from you guys and perhaps get some more feedback or some more info i can research. please be nice.:surprised
     
  2. jcsd
  3. Aug 17, 2006 #2
    Well gravitational lensing does change the apparent positions, sizes and shapes of objects in the universe, and we can even see multiple images but we are lucky since we can calculate the effects! :smile:

    No, while light emitted in a gravitational field slows down its frequency, gravitational lensing by itself does not influence it.

    But we can calculate backwards right?

    Presumably at the center of all mass! :wink:

    The explosion by itself, as you call it, would not impact the time dilation factor. Everything is part of that "explosion" so we all have the same factor right?

    The expansion is everywhere so from each perspective it would more or less be the same.
     
  4. Aug 18, 2006 #3

    Chronos

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    Interesting comment, MeJennifer. I perceive your are not as naive as the moniker suggests. I've also noticed you make too many well informed remarks to disguise the fact you know exactly what you are talking about. In fact, I doubt your name is Jennifer . . .
     
    Last edited: Aug 18, 2006
  5. Aug 23, 2006 #4

    So you're saying that, gravitational lensing isn't the only thing that could impare our perspective of the age of the universe?

    we can't calculate backwards if we really don't have anywhere to stand on first, and we don't. without knowing the size of the explosion, or being able to see its effects (the effects of an explosion that large could be extremely numberous, meaning we would only know a very small fraction of them, seeing that we are actually inside the explosion).

    Could you please refer me to this "center of mass"? from what i can see, seeing that we can't see to the other side of the universe, we therefore do not know where the other side is, nor the center, where the explosion would have occured. just because we can see a long ways out doesn't mean we can see all the way out.

    i would suspect that everything is not part of that explosion, and that, just like a firecracker, certain portions, because of the effects of its surroundings at very specific points in time, would have compeltely different effects, becoming very large as we make the explosion larger.

    yes, the explosion is everywhere, but with a huge time dilation factor starting immediately after the explosion, one would assume that the parts of the explosion (fragments) that left the mass first would be farther away, thus 'deaccelerate' faster than that which is behind it, even by a small fraction, which, by terms of time dilation, would allow even more distance to be taken, giving an even larger gap between the fragments that were slightly behind it, allowing it to completely stop its acceleration and continue floating as normal, cooling off, and becoming normal, while the others which we still yet closer to the explosion still have an accelerative force behind them, allowing them to move faster than the ones in front of them, eventually catching up.

    make any sense?
     
  6. Aug 23, 2006 #5

    DaveC426913

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    Funny you would say that, I've been thinking a similar thing. Thre first post I came across by MeJennifer made me think s/he was VERY inexperienced. But later posts - after I'd formed a mental model of MJ - powerfully belied that first impression.

    (Though IMO, I don't know why his/er moniker is necessarily either naive or faked.)
     
  7. Aug 23, 2006 #6

    russ_watters

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    Have you read about Hubble's worh measuring redshift, and correlating it to distance, christian_guy?

    This isn't really my area, but I've never seen anyone suggest that gravitational lensing could be used to determine the age of the universe. Where did you hear that?

    Also, your understanding of what the big bang was is quite badly flawed. You may want to read up more about it.
     
  8. Aug 24, 2006 #7

    Chronos

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    Just my impression, Dave, MeJennifer appears, at least, to have a steep learning curve. I'm not picking on MJ, merely admitting his/her more recent comments surprised me.
     
  9. Aug 24, 2006 #8
    MeJennifer is a top poster here in my books, she is right up there with pallidin and pervect.
     
  10. Sep 6, 2006 #9

    selfAdjoint

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    I see MeJennifer as a grad student; she has learned a lot (and not from us) in the past few months. Steep learning curve, yes, but she's on or ahead of it.
     
  11. Mar 2, 2009 #10
    Aren't you all forgetting the affects due to time dilation on the age of the universe? The universe isn't one age. It's infinite ages, depending upon where you are in it.

    Suppose the big bang happened with a velocity vector in some arbitrary direction (in addition to the vectors in all directions from the explosion). Say one of the galaxies traveling from the big bang along the path of that vector is our galaxy. We could be moving at near light speed with respect to the point of origin, and not even know it. To us, the effect of time dilation would be extreme, and the universe could be very young, while to someone on the other end of the big bang bubble, could have the opposite effect, and the universe could be very old.

    I've created a computer model that demonstrates this effect. It's a very small 3D application.
     
  12. Mar 2, 2009 #11

    DaveC426913

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    This makes no sense. With respect to what is this 'velocity vector in some arbitrary direction' measured?
     
  13. Mar 3, 2009 #12

    marcus

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    You are trying to talk in terms of the standard cosmo model that virtually everybody uses.
    That's where the usual numbers come from, including the age of the universe.

    Galaxies are not "traveling" away from some "point of origin".
    That is not what the expansion model of cosmology is about.
    Please take the time to ready a Scientific American article called Misconceptions about the Big Bang.
    I have the link in my sig. It is the princeton.edu link.

    You are suffering from one of the commonest popular misconceptions, picturing the Big Bang as a explosion with stuff flying out from a point of origin.

    Recession rate of most galaxies we can see are several times greater than the speed of light and there is no "time dilation". Special relativity effects like that do not apply. Recession is not ordinary motion (if it were it would have to obey the speed limit! :biggrin:)

    Better read the SciAm article in a hurry, Barbeau, you'v got catching up to do if you want to learn mainstream cosmology :smile:
     
  14. Mar 3, 2009 #13
    The age of the universe is NOT one of the many great unknowns....
    Wikipedia gives a decent overview: http://en.wikipedia.org/wiki/Age_of_the_universe
    and pegs it between 13.61 and 13.85 billion years....

    of course such consensus science has usually been WRONG!!!!!
     
  15. Mar 3, 2009 #14

    marcus

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    I will wager that this estimate will only be refined and further confirmed as more information comes it. But ironically it will turn out not to be the age of the universe but the time since the bounce.

    In other words, if it turns out to be wrong (as you suggest) it will not be because the number is wrong but because the rules of interpretation change. The universe may have no beginning, but the current episode of expansion we are witnessing may have begun some 13.7 billion years ago.
     
  16. Mar 3, 2009 #15
    In dealing with explosion, relativity does not apply because it is a space expansion, and remember that simply everywhere is the center like balloon analogy-- so no time dilation. Regarding time dilation in the early big bang I do not believe we can get any useful thing, because the absolute time itself is very hard to have meaning (to human?) separated from physical something changing, like motion or reaction etc, but we can raise a question like the modern physical principles like quantum and relativity can apply during those time or modification is needed.
     
  17. Mar 5, 2009 #16
    time,space,mass likely were unrecognizable to us....vast amounts of radiation energy would have prevented any formation of atoms....no stars,no planets, just incredible temperatures,energy,radiation.....as an analogy, perhaps consider the energy in a nuclear explosion times factor of a million or a billion....anyway, about the only thing that exists during such a period are quantum fluctuations which over eons gravity converts into stars and planets and galaxies.
     
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