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Aescorvo t1_j0gs39z wrote

Actually, let me amend what I said. Without looking out the window (metaphorically) you couldn’t tell. However, if you had a clock on board, and and an identical clock far enough away that it was effectively in zero gravity, AND you could view it through a telescope each revolution, you would (eventually) see that the clock runs faster than yours. That would at least tell you that it was experiencing lower gravity than you were.

This is akin to one of the effects that we have to account for with GPS satellites. Putting a clock in orbit (with a big enough display) would let us see the discrepancy compared to an identical clock on the surface, deeper in the gravity well.

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alukyane t1_j0h92dr wrote

We then seem to agree that the top-level claim above about acceleration is wrong: you can't actually tell whether you're in an inertial or accelerating frame, if the acceleration is the same for all observable objects. Right?

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