Will the Universe End in a Big Rip?

Discussion in 'Astronomy, Exobiology, & Cosmology' started by wet1, Mar 9, 2003.

  1. wet1 Wanderer Registered Senior Member

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    Will the Universe End in a Big Rip?
    Illustration Credit & Copyright: Lynette Cook

    How will our universe end? Recent speculation now includes a pervasive growing field of mysterious repulsive energy that rips virtually everything apart. Although the universe started with a Big Bang, analysis of recent cosmological measurements allows a possibility that it will end with a Big Rip. As soon as few billion years from now, the controversial scenario holds, dark energy will grow to such a magnitude that our own Galaxy will no longer be able to hold itself together. After that, stars, planets, and then even atoms might not be able to withstand the expansive internal force. Previously, speculation on the ultimate fate of the universe centered on either a re-collapsing Big Crunch or a Big Chill. Although the universe's fate is still a puzzle, piecing it together will likely follow from an increased understanding of the nature of dark matter and dark energy
     
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  3. blobrana Registered Senior Member

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    (Work done by John Webb, New South Wales University. )
    Analysis of the light coming from distant quasars suggests that a fundamental physical constant may have been increasing slightly over the past six billion years.
    The so-called fine structure constant - which measures the strength with which subatomic particles interact with one another and with light - may have been smaller at earlier times in the history of the Universe.
    The team looked at so-called absorption lines in the spectra of quasars, the highly active, bright cores of galaxies at the farthest reaches of the Universe.

    Gas clouds between Earth and the quasars absorb some of this light at specific wavelengths and produce the spectral lines.

    The spacing of the absorption lines depends upon one of nature's fundamental numbers: the fine structure constant or alpha.

    Alpha is something that is built into the very fabric of the Universe. It is a dimensionless number, the ratio between four physical constants: the speed of light, the quantum energy constant, the charge of the electron and pi.

    The value of alpha, currently about 1/137, determines much about the way the Universe works.

    (These dimensionless numbers are much more important than any of the dimensional constants)

    Alpha determines the strength of interactions between charged particles and electromagnetic fields, and, as such, is central to the understanding of electromagnetism - one of the four fundamental forces of nature.

    ( BTW, Alpha is the central parameter in anything to do with atoms, electricity, magnetism - everything except for gravity)

    The spacing between the wavelengths absorbed by the intervening atoms depends on alpha. If alpha changes, then so will the absorption pattern in the spectra.

    The researchers looked for this effect using the world's largest telescope: the 10-metre Keck facility in Hawaii.

    Dr Webb and his co-workers found evidence that alpha was slightly smaller in the past than it is now.

    The team say there is a one in 10,000 chance that the result is a statistical fluke. They also say they have eliminated 13 potential sources of systematic error.

    the so-called constants of the Universe that appear in the equations for the fundamental laws of physics - such as the speed of light in vacuum and the electron charge - MAY not be constant.
    The current value of alpha could not have been very different in the past. A small variation in alpha would imply that carbon atoms could not be stable, and carbon-based life such as us could not have arisen.

    In fact, modern attempts to unify gravity with the other fundamental forces do allow for Nature's constants to vary.

    Proposed theories can accommodate changes in alpha over time. Known as string theories, they allow either a 10- or 26-dimensional universe, rather than our 4D one.
    But having said that,
    The big rip will only happen IF the cosmological constant, is not a constant...And only IF it is increasing...

    I think that it would be reasonable to think that the CC is a constant (less hassle), and that if anything WERE to change over time then it would be the value of gravity.
     
    Last edited: Mar 9, 2003
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  5. shadows technocrat:Teach me Registered Senior Member

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    perhaps the universe will cancel out and create a new universe on a different fequency. There is aot of empty space in matter. Maybe this space is decressing as energy is being moved to other universes. This would mean that we are near the end of this one.
     
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  7. blobrana Registered Senior Member

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    you may have to explain/expand to me a few/all of those ideas.

    Do you mean the quantum wavelength of a baby universe when you refer to the `frequency`?

    I think that it is possible for the inflation energy of SPACE to be converted to other forms of energy.

    Are you saying that energy is leaking to another universe?
    (i wish i had a link to membrane theory)
     

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