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Please clarify - Spacetime

  1. Oct 16, 2009 #1
    Please clarify / correct my misunderstanding. I'm not a physics pro (just a personal interest). Also, please excuse the complete lack of technical terms!


    It has been said that to move beyond the speed of light is to move backwards in time? (Though it's also stated that this isn't possible for matter?)

    The speed of light isn't constant - that is to say it is affected by forces such as gravity?

    Gravity appears to cause "compression" of mass ie higher density, and has a huge range, though it's effects appear to dimish sharply with range? (or vice versus depending on your perspective)



    I heard a comment some time back about the rate of the universe expanding at an increasing rate.

    First question: What methods were used / how do we determine the universe is growing at an increasing rate when we the observer are sat in a gravitational field and are thus subject to the same distortion of space/time?

    Is the typical "schooled" approach entirely misleading, portraying atoms etc as having fixed bounds and areas they "occupy", and would it be more accurate to portray the "effect" of am atom as being those of numerous flows or fields or "folds"?

    If this is the case, can they "scale" up or down? To put it in other words, can 1 cubic meter of space "on paper" represent 2 cubic meters, with the propogation of all waves ie space/time being at 1 constant unit, but 1 cubic meter on this planet "on paper" representing 2000 cubic meters of space, with waves propogating at a much higher rate?

    Sorry if the last bit makes little sense - hopefully someone will understand what i'm getting at despite the bad wording.
     
  2. jcsd
  3. Oct 16, 2009 #2
    Dr Einstein wrote a plain English exposition of Relativity which I have seen posted as a .pdf file on the web. In fact I just tried the terms 'Einstein, relativity, .pdf' as seeds for a google search and can report ready availability.
    I think that your questions are easier to ask than to answer, and that Einstein will set you right.
     
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