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Spacetime to mass

  1. Jul 20, 2006 #1


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    If mass warps ST then can warped ST generate mass? For example, if I warp ST around a point (in ST) will that point have inertia? Will it be atracted to masses that warp ST more. Does this question make any sense? Thanks.
  2. jcsd
  3. Jul 20, 2006 #2


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    Gravity waves are just ripples in space-time. However, they carry energy and momentum. As is the case for light, E^2 - p^2 = 0 (in geometric units), so a single gravity wave is massless. As is also the case for the light, if you have a pair of gravity waves travelling in opposite directions, the total momentum p is zero, but the total energy E is greater than zero, which means that the system comprising the pair of gravity waves has mass.

    In GR gravity couples to energy (more precisely, the stress-energy tensor) rather than mass, anyway. The idea that gravity couples to mass is basically a carryover from Newtonian gravity.
    Last edited: Jul 20, 2006
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