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Is space a property of matter?

  1. Dec 8, 2009 #1
    What is the essence of space? Is it a property of matter? If not, is it an entirely new stuff distinct from matter? If the former is true, why does space seem so homogeneous to us while the distribution of matter seems so uneven. If the latter is the case, what does it mean by the matter without space, or the space without matter? If both is not the case, what is the fundamental relationship between space and matter? Is the concept of space just a convenience without real substance? Then what does it mean by general relativity describing distortion of space due to gravity?

    Pardon me, these may seem to be a bunch of dumb questions as I didn't study physics in college.
    Last edited: Dec 8, 2009
  2. jcsd
  3. Dec 8, 2009 #2


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    There was an era in the universe when there was plenty of space but no matter. It was too hot for matter to condense out of energy.
  4. Dec 8, 2009 #3
    Thank you for reply, Dave. I thought energy counts as matter, too. According to E=mc^2, matter and energy seem equivalent though they have different forms. Let me rephrase my question, is there a possibility of the space deprived of both energy and matter, "and" energy and matter without space?
    Last edited: Dec 8, 2009
  5. Dec 8, 2009 #4


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    It's true that there is an equivalency, but that does not mean that one is the other.

    A one dollar bill and 100 pennies are equivalent, but that does not mean that 100 pennies can be folded into a sailboat. :wink:

    Even the erstwhile empty vacuum is seething with energy. It has been so since very shortly after the Big Bang.

    So I don't really have an answer to your question, just more questions...
  6. Dec 8, 2009 #5


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    There are two notions of "space" in general relativity. There is the featureless smooth manifold on which everything occurs. Then on the manifold there is the "metric" field, and "matter" fields which include the electromagnetic field, which many would say is a force field, just like the metric field. The metric field can be used to provide notions of distance and time, and forms the other notion of "space" or more properly "spacetime" in general relativity. However, fundamentally, the metric field is just another force field produced by matter, just like the electromagnetic field is a force field produced by charged particles. Because the metric field is produced by matter, and also provides notions of distance and time, it is therefore said that matter curves spacetime.
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