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Name: EG Young
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: Around 1999


Question:
It seems to be the case that as larger and larger scales are observed more and more missing mass (dark matter) is need to balance understanding with observation. This appears to result from the 1/rr law of Newtonian gravity. We know that as scales become smaller Newtonian physics must eventually be replaced by quantum mechanics; and that all theories fail when tested against some extreme condition. What besides familiarity leads to the 1/rr law being used for large scale study of the universe? Has there been any serious consideration of possible alternatives to the 1/rr law? Do general relativistic models, such as the DeSitter universe, make a difference?



Replies:
A very simple answer is that 1/rr comes out of relativistic models in a very natural way at large distances. I don't think that there is any compelling reason to consider this as it would be a sort of change in gravity as opposed to the distribution of mass. For relativity the whole question is where is the mass distributed. From that you can determine the fields.

Sam B



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