Repulsive Gravity & Its Impact on Space Geometry

flotsam
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I know that there are people with the idea that at great scales in space gravity is repulsive. Could someone tell me how this fits with the geometry of space. It is clearly bad news for GR if this is correct. How does repulsive gravity shape the geometry of space if indeed it does?
 
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The observational evidence (based on type Ia supernovae) is that the expansion of the universe is speeding up - that's where the idea of repulsion comes in. This is consistent with GR when Einstein's cosmological constant is included in the equations.
 
So if it were found to be true that on great scales gravity is indeed repulsive it does fit in with GR if the cc is included, good. But I can imagine GR geometry shaping space in my mind right now. To imagine repulsive gravity shaping space do I just turn this picture upside-down?
 

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