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Which conserves energy better? Expanding space or Shrinking matter?

  1. Feb 3, 2008 #1
    How would we ever tell the difference between a universe that has expanding space and a universe that has shrinking matter?

    How do we reconcile our beliefs about the conservation of energy with the notion of expanding space?

    Wouldn't it be easier to account for energy if it involved shrinking matter?

    Can the notion of shrinking matter (as well as the shrinking space around it) be reconciled by string theory or some other similar unification theory?

    Perhaps matter is shrinking at an accelerated rate, explaining why supernovas at some redshifts are dimmer than they are supposed to be?

    At some point, some places in the universe would have matter shrinking faster than others, making those other places experience a universe that appears, to them, accelerating away to oblivion?

    Maybe we could discover other places where matter was shrinking more slowly?

    Maybe the most distant galaxies which appear faded (although large in terms of angular size for their actual size) are shrinking a slower rate and therefore experience a less accelerated universe?

    Maybe the shrinking of one galaxy affects the development of other galaxies? Like a Julia set?

    Maybe the shrinking is due to billions of years of scaling down of atoms and molecules as a result of energy leakages from the smallest scales of matter (entropy losses)?

    Maybe as time progresses, this energy that is lost is simply lost to the empty space causes energies within atomic, molecular, and gravitational systems to move around and smaller and smaller distances?
    Last edited: Feb 3, 2008
  2. jcsd
  3. Feb 3, 2008 #2


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    if matter were shrinking then our metersticks would be shrinking and the distance to the sun would be a larger and larger number of meters.

    also the diameter of our Milkyway galaxy would be a larger and larger number of those meters.

    It would be easy to tell the difference.

    the real world has some distances expanding and others not
    according to the GR theory of gravity.

    this is very different from your imaginary world where we have our metersticks shrink so that all distances become a larger number of meters

    Your world would not follow GR. I don't think there would be any recognizable law of gravity

    why do you want to get rid of General Relativity? it is the most accurate law of gravity we have. sounds kind of foolish if you ask me.
  4. Feb 3, 2008 #3


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    Shrinking matter? This is just another variant of the 'tired light' hypothesis that does not survive scientific scrutiny. Need any peer reviewed paper references?
  5. Feb 3, 2008 #4
    I'm not talking about the idoitic expanding earth hypothesis. That's b.s. No. I am taking about where instead of "rather uniformly" expanding space relative to matter we have matter "rather uniformly" shrinking relatively to space.

    Einstein's theory of gravity combined with the cosmological principle implies that the universe is not stable and must either expand or contract. Isn't that relative in of itself? Using one coordinate system, you will very well get the expanding space. Using another, you might have matter shrinking relative to space. Why is one preferred over the other?

    GR is in combination with Schwarzschild, Kerr, Logarithmic, and many other metrics; there is not only one kind.
    Last edited: Feb 3, 2008
  6. Feb 3, 2008 #5


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    You could try writing down mathematically what you mean. I doubt you could do it, because I doubt that what you are proposing has any precise meaning. But you could try and it would be interesting to see the result, if you succeeded!

    One trouble with your idea is that----well first of all space is not expanding that is a verbal shortcut and gives people the wrong idea immediately. DISTANCES are changing, and different distances are changing at different rates. Not all distances are expanding.

    and the next trouble is that if you translate the picture of a dynamic metric into talking intuitively about "space expanding", then there is no one rate of expansion, different blobs of space are expanding (or contracting) at different rates

    and the blobs arent very well defined, and will most likely (if you try to define them) depend on the observer's perspective.

    So you would be unable to say at what rate you want matter to shrink. Or even relative to WHAT you want it to shrink.

    The basic trouble, Marinas, is that your words only sound superficially as if they mean something. I don't think there is any well-defined mathematical substance to what you are proposing.

    But go ahead and show us, if you can!
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