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- Time Dilation When In Orbit 1 answer
When orbiting a massive object, perhaps a neutron star, you maintain your altitude while at the same time you are close to a very strong gravitational field. Being in orbit, and being in free fall is indistinguishable for the object in question. The object is not affected by gravity, locally.
Another free falling object can't be "less affected" than this first object, since the first object is in fact not noticing any gravity. Logically, both object should age equally fast if we ignore the relativeness of aging.
There is no doubt that the gravitational field is strongest around the first object, but neither object experiences any gravitational field. Object one looks at object two is in free fall, and vice versa.
Of object one records a video of object two, and then later plays that video - but adjust the playback rate to account for all doppler shift effects - what would object one see?
Is doppler the only effect causing the difference in relative aging in this case?