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I have the impression that the idea was: mass doesn't cause gravitational force; it merely bends space time, and that's why an apple falls towards the center of Earth:

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and some people think: oh, if a bowling ball is on the sofa seat, then sure, a tiny metal ball near that will fall into that indentation. I get it. It is so sparkling clear.

But if the thinking is really is like that, it is using gravity experience to explain the effect of bending of space time.

If Newton's First Law still holds, then an apple that is cut from the branch of the tree, even in the presence of bending of space time, it experiences no external force. So why would it follow whatever bending of space time and falls towards Earth? How is this explained?

nonopolarity
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    although those answers seem to try to explain it, they were saying "travel in straight line"... well, if we see the apple not traveling at all, why is it all of a sudden "traveling"? – nonopolarity Dec 22 '22 at 05:55
  • This may help - A new way to visualize General Relativity – mmesser314 Dec 22 '22 at 06:39
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    ok, at least you are not pointing me to the Halliday textbook from page 1 to 1200. This video, and the other book Relativity Visualized by Epstein, says, everything in the universe is constantly moving at the speed of light, and it depends on whether it is x, y, z, or t. So according to the video, it is saying, the apple, when cut from the branch, is still going at a velocity of the speed of light, but only on the t axis. The Earth bends the space time so that the apple now travels less on t and more on x, y, and z. – nonopolarity Dec 22 '22 at 08:12
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    And I suppose the bending is more like less and less of t and more and more of x, y, and z, so that the velocity constituted by x, y, and z becomes greater and greater to make it a greater speed. – nonopolarity Dec 22 '22 at 08:14

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