If the universe is 13.8B years old, how can we see 46B light years away? (2018)

Re:If the universe is 13.8B years old, how can we see 46B li... by coding123 on Saturday December 07, 2019 @11:54AM (#21731211)

I feel like we are all idiots repeating "space is expanding" if humans could live 14billion years in age, and we were present when it started, but we left good old Bob on the part of the universe that was travelling away from us, he would have traveled FTL from us. Even if you said space expanded, the traveling has been accomplished. So now we know that space expansion is how you travel FTL.

In other words if humans ever invent warp, the space expansion work around we would effectively have FTL travel.

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Re:If the universe is 13.8B years old, how can we see 46B li... by beisner on Saturday December 07, 2019 @12:02PM (#21731256)

Just a minor technicality, it’s not that Bob travelled faster than the speed of light, it’s that the distance between you and Bob increased faster than the speed of light. Nothing can travel FTL through space, but space itself can be made smaller or larger.

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Re:If the universe is 13.8B years old, how can we see 46B li... by simonh on Saturday December 07, 2019 @01:21PM (#21731706)

Ok, but you can’t use it to go to anywhere FTL. You can only use it to get further away from somewhere FTL.

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Re:If the universe is 13.8B years old, how can we see 46B li... by gls2ro on Saturday December 07, 2019 @04:19PM (#21732625)

I think we can use it to go back to a place. It is the same as going further just that now we “just” need to shrink the space. Of course all is so far just an exercise of our imagination.

You can take a look at the curvature or more concrete to the density of the Universe. It is possible to be positive and in this case at one point in the future the Universe will collapse back on itself. Nothing will stop it to do this apparently FTL.

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Re:If the universe is 13.8B years old, how can we see 46B li... by rfhjt on Saturday December 07, 2019 @08:14PM (#21733783)

Unless we create a link between two points nearby ahead of time, wait for a billion years and then use this link to jump between the two points. In fact, I think that such links exist everywhere between any two points in space, but they remain latent in the form of quantum entanglement.

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Re:If the universe is 13.8B years old, how can we see 46B li... by saagarjha on Saturday December 07, 2019 @04:16PM (#21732605)

https://en.wikipedia.org/wiki/Alcubierre_drive

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