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The way I understood general relativity is that there is no force of gravity but instead all object just move forward but the space they move through is distorted and that's why their trajectory seems to be different than a straight line. Now here is the question, if an object is not moving at all, i.e. it has no speed, does that mean that even though space is curved around them there is no speed to move the object towards the larger object?

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  • $\begingroup$ If an object has 'no speed' then it can't be freely falling in a curved spacetime. (I.e. there's some external non-gravitational force on it). $\endgroup$ – Eletie Nov 29 '20 at 18:30
  • $\begingroup$ You are always moving within spacetime. Your scenario is not possible. $\endgroup$ – m4r35n357 Nov 29 '20 at 18:34
  • $\begingroup$ I understand that you are always moving through time but how are you always moving through space? @m4r35n357 $\endgroup$ – Warix3 Nov 29 '20 at 18:36
  • $\begingroup$ Time and space should be treated on equal footing, so that one talks about paths (worldlines) through spacetime as a whole $\endgroup$ – Eletie Nov 29 '20 at 18:37
  • $\begingroup$ So if an object moves through time that automatically makes it move through space too? How does that work? @Eletie $\endgroup$ – Warix3 Nov 29 '20 at 18:39
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If an object is initially static from a larger object (assuming they have the same density), it will follow the geodesics in space-TIME. So the answer is yes because space-time is curved by the second object. This is why when you drop an object, it falls down to earth.

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  • $\begingroup$ Does that mean the object with no speed would be affected by the gravity of the larger object and move towards it? $\endgroup$ – Warix3 Nov 29 '20 at 18:37
  • $\begingroup$ In the referential of the larger object, the first one will progressively acquire speed, though initially, it did not have any. $\endgroup$ – Jeanbaptiste Roux Nov 29 '20 at 18:53

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