Can the curvature of space-time in general relativity describe an apple falling from a tree? - by Michael Mooney, by Kip Ingram and by Patrick Dolan- Quora Question Review

Is it Can the curvature of space-time in general relativity describe an apple falling from a tree? - by Michael Mooney, by Kip Ingram and by Patrick Dolan - Quora Question Review

This document contains a review of the answer by Michael Mooney, by Kip Ingram and by Patrick Dolan on the question in Quora: "Can the curvature of space-time in general relativity describe an apple falling from a tree?"
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: No. "Space-time" is not a real thing with shape, including curvature. Space is emptiness and time is our *concept* of the duration of specified movements (like Earth's rotation and orbit.) Neither emptiness or the concept of time (or both "woven together" replace the universal pulling force of gravity.
The *force of gravity* is generated by all masses… stronger the more mass interacting and weaker with distance between masses. Earth's gravity pulls the apple to the ground. No curved fabric (or whatever imaginary medium) is involved.
IMO this is the right approach. There is one problem, in Newton's mechanics Gravity acts instantaneous. That is physical not possible. To make this model physical acceptable the speed of gravity has to be accepted. It should be mentioned that the speed of gravity and the speed of light are physical two complete different parameters.

: Sure - that's exactly what it does. You'd plug the energy distribution represented by Earth (and everything else in the vicinity of the apple tree) into Einstein's field equations and you'd solve for the metric tensor g everywhere.
You have to add the energy distribution of all the stars in the universe. That is extremely complex.: Then you'd put that into the geodesic equation, and it would reveal to you that as soon as the stem snapped the "normal inertial path" of the apple (that is, it just trying to move on a line that was as "straight as possible" in spacetime) would map out its fall to the ground.
This is really the entire point of general relativity.
The entire point of Newtons Mechanics and general relativity that you have to include all the massa's in the Univerese.




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