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In the Modified Theory of Newtonian Gravity or MOND, they say that massive objects, accelerating slowly, experience this modified gravity.

But are they actually gaining in velocity, albeit very slowly?

Or are the MOND theorists using the term "acceleration" differently, as in the sense that all objects in a gravitational field are accelerating, even if they soon end up traveling at a constant velocity?

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    $\begingroup$ "Acceleration" means changing the velocity vector, so an object in a circular orbit is always "accelerating" (because the direction of the velocity changes), even if its speed is constant. $\endgroup$ Commented Feb 11, 2021 at 15:55
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    $\begingroup$ Thank you.... I was losing my mind..... $\endgroup$
    – Kurt Hikes
    Commented Jun 2, 2021 at 11:00

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As @PeterErwin's comment compassionately points out:

"Acceleration" means changing the velocity vector, so an object in a circular orbit is always "accelerating" (because the direction of the velocity changes), even if its speed is constant.

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    $\begingroup$ There, I made Peter Erwin's 'comment' an 'answer'.... I hope that is okay.... $\endgroup$
    – Kurt Hikes
    Commented Jun 2, 2021 at 11:03
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    $\begingroup$ It's always okay to answer your own question, even if its by promoting a comment into an answer, and to accept your own answer as well. But it's still important to make it a good Stack Exchange answer post. I've tidied up a bit. $\endgroup$
    – uhoh
    Commented Jul 2, 2021 at 23:32

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