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  On the interpretation of general theory of relativity

+ 0 like - 0 dislike

GTR only redirects the question of why an apple falls, replacing it with a much deeper, perhaps even metaphysical question; why does matter bend spacetime?

Although there have been many direct and non direct confirmations of the theory, how bluntly should we really interpret it's assertions considering also all the the other questions it brings up;

( 85 percent of matter in the universe remaining hypothetical,almost all matter and energy completely undanstood. )

Also is it right to say that to a distant observer an apple and the Earth have no spatial velocity, only their worldlines meet due only to the movement in time directions in curved spacetime, so the neither the apple nor the earth actually move an inch through space, only through the time direction?

asked Nov 24, 2018 in Chat by anonymous [ revision history ]
recategorized Nov 25, 2018 by Dilaton

1 Answer

+ 0 like - 0 dislike

I believe that the reason for matter bending spactime it's not metaphysical at all. It is suggested, or rather demanded by, the equivalence principle and special relativity. So Einstein did not just pull it out of thin air, he had good physical reason to understand gravity in that way.

answered Nov 25, 2018 by facenian [ no revision ]

Equivalence principle or not its just a slight improvement and a fancy way of expressing 500 year old classical physics. EQ principle doesn't apply consistently to QM, and there have been no deep, fundamental indications as to why EQ or space time curvature should be of any real meaning..

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