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Does Gravity expand space

  1. Oct 21, 2015 #1
    When watching a video of an explanation of Einstein's theory of General Relativity, you will see a star or planet distorting the fabric of space. This is always a 2 dimensional plane oriented in the x axis that gets "dished" by the larger star or planet and the satelite will then roll around inside this dished out area (gravity).
    However, this distortion of space would be in all dimensions and orientations, and when you look at it with all the distorted planes in view, it would seem that gravity has expanded space.
  2. jcsd
  3. Oct 21, 2015 #2


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    No, the "distortion" that you see in pop-sci is really just a "curvature" when represented in Euclidean Geometry that does not exist in the actual Riemann Geometry of space-time, where the path is NOT "curved" but is a straight line (formally, a "geodesic"). What you see in pop-sci is the best that can be done with a 2D representation of something that really can't be truly represented well in 2D, and pop-sci isn't likely to bring reality into the picture by talking about Riemann Geometry.
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