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Artikay t1_j1gszt9 wrote

Reply to comment by duckiegooseman in Did you know it will still take 46 billion years to cross the universe at the speed of light? 65 mph = 4.8 * 10^17 years! by NotAndroid545

So if you place Earth in the center of our observable universe, and call it Planet A, then you take two planets on the far opposite ends and call them B and C. Does that mean to Planet A, B and C can be seen, but to planets B and C only Planet A can be seen?

Basically B and C have more than one observable universe between them? It would take exponentially longer for light to reach between stars because there is more space to expand between them?

If there is so much space between ends of the universe could two points be so far apart that light could never get from one end to the other?

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Wind_14 t1_j1gu400 wrote

the last one is the consequences of observable universe though. Yeah there's a point where light simply can't reach the other side, because the expansion is faster than the speed of light, thus limiting the size of the observable universe (of course, this is assuming our prediction/projection is really true which is the farther an object is from the center the faster the expansion rate is between them and center).

And you don't have to assume that earth is the center of our observable universe, since it is (or rather the center of your observable universe is you).

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duckiegooseman t1_j1hf4ic wrote

Yes to the last question. Actually since the universe is accelerating faster than light, every second more and more "things" get so far away they are "lost" to us permanently because light from them can never reach us anymore. At some point far far into the future, our cosmic horizon would be complete emptiness in every direction, and our galaxy would be the only thing that even exists to us anymore.

But to B and C, they don't exist for each other. Information from B can never reach C and vice versa.

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