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A comment on Proving our universe is one among many would be a fourth Copernican revolution. Parent comment

Re:Proving our universe is one among many would be a fourth ... by lisper on Friday September 28, 2018 @03:38PM (#18096392)
> within existing theory, the location of "the farthest we can see" is not particularly meaningful physically

Except that you can always put a finite upper bound on that distance. That is what matters with regards to the topic under discussion.

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Re:Proving our universe is one among many would be a fourth ... by btilly on Friday September 28, 2018 @04:36PM (#18096829)
Which means that it is exactly as meaningful as the event horizon of a black hole. The last point where the external observer (ie us) can see what happens. But in a different coordinate system, not particularly special at all.
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Re:Proving our universe is one among many would be a fourth ... by lisper on Friday September 28, 2018 @04:49PM (#18096943)
Yes, that's right. Different observers have different light cones. Yours is a little different from mine. But that is missing the point, which is that every observer has a light cone beyond which they cannot see -- not even by collaborating with other observers with different light cones.
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