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Comment by madmads | Hacker News Reader

I mean the universe is so incredibly vast that even if we figure out how to travel at the speed of light, we'll only ever get to see a small fraction of it. I don't think we'll have to worry about running out of places to explore.

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So, about that. One of the weird things about General Relativity is that if we COULD travel at or near the speed of light, then time dilation and length contraction will conspire to enable a trio to the end of the observable universe in 30 years.

So we could definitely explore the universe, we just have no way to share what we discover with our friends back home.

This is forgetting to account for the accelerating expansion of the universe. Even if one were to depart from Earth today, traveling at light speed, 94% of the observable universe is already impossible to reach. See this excellent video for more detail: https://m.youtube.com/watch?v=uzkD5SeuwzM

Still, the observable universe is only a small fraction of the whole universe (we believe, based on spacetime curvature, I think).

For the timelines we are discussing here, sure there will lots of new discoveries in physics. And who knows may be somebody will toss out what we know today and come up with something new, where none of these limitations we know today apply.

> we'll only ever get to see a small fraction of it

True, but on the other hand, due to relativistic time dilation, a very fast traveller could visit very far away destinations if they get closer and closer to the speed of light.

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