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CarolBaskinDidntDoit t1_jb1985y wrote

Reply to comment by Aseyhe in Does the age of the universe depends on where you are? by _bidooflr_

In a similar (and possibly dumb) question: When we say that the expansion of the universe is accelerating, is it possible that the objects at the far edges of the universe are actually travelling at constant velocity from their reference, but as they get further away from the gravitational center of the universe, the time dilation reduces what a second is and therefore appears from our reference to be accelerating?

E.g. if a=dv/dt. If we measure the velocity of the distant object for an arbitrary amount of time - say 10,000 seconds. And let’s say the object is travelling at constant velocity, but as the object gets away from the gravitational center, a delta 10,000 seconds from the object’s reference would be shorter than a delta 10,000 seconds from our reference. So therefore we perceive this as a change in velocity?

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bluesam3 t1_jb1txud wrote

The universe expanding isn't anything to do with objects having velocities: it's the space between them getting bigger.

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Howrus t1_jb2mmeo wrote

> objects at the far edges of the universe are actually travelling at constant velocity from their reference

That's the neat trick - they are not traveling at all! Expansion of Universe is happening because space between everything is growing, not because something is flying away.

Closest analogue would be - draw two points on a balloon and start inflating it. Distance between this two points would start to increase without them moving by themselves.

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