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Does an apple "falling" from a tree move only in the time direction in curved spacetime?

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Does it appear to a distant observer that the distance between the earth and the apple is decreasing as they move along their geodesics but only in the time direction , and in reality neither the earth or the apple move through space?

Closed as per community consensus as the post is not graduate-level

asked Nov 25, 2018 in Closed Questions by anonymous [ no revision ]
recategorized Nov 27, 2018 by Dilaton

not graduate+ level. Users with 500+ reputation may vote here to close.

PhysicsOverflow is a site for advanced physics. Please ask elementary
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commented Nov 26, 2018 by Arnold Neumaier (15,787 points) [ revision history ]

I bet you can't answer it correctly..

commented Nov 26, 2018 by anonymous [ no revision ]

Your statement reveals elementary problems in understanding the notions involved. Motion ''in time only'' depends on the coordinate system used, and would imply in this coordinate system that the spatial distance does not change, which is obviously wrong.

commented Nov 27, 2018 by Arnold Neumaier (15,787 points) [ revision history ]

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1 Answer

In GR "moving through space" is implied; otherwise the notion of space would be useless. You mistake a "free motion" in space (=along geodesics) for "no motion at all".

answered Nov 27, 2018 by Vladimir Kalitvianski (102 points) [ no revision ]

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