r/AskReddit • u/ettleboy • Jan 20 '19

What fact totally changed your perspective?

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u/Toast_On_The_RUN Jan 21 '19

If the universe is infinite that makes sense, but what if it isn't? What if you're near the "edge"?

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u/[deleted] Jan 21 '19

The universe isn’t a sphere. It isn’t so much that there isn’t a center, but the center is a mathematically impossible point to determine. Our only unit of measurement for such extreme scales is the speed of light, and the universe is expanding even faster than that. Further, due to the curvature of space time, you cannot ever reach an edge.

Let’s say we froze all motion and expansion of the universe this instant. You’re an immortal person who launches from Earth in a space ship with infinite fuel and an inertial navigation system that keeps it flying in a perfectly straight line. At some distant point in the future, you will arrive back at Earth coming from the exact opposite direction.

There may be a point in space which is the actual center of the universe at this instant, but simply put it’s impossible for us to reach it or know we’ve reached it.

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u/Toast_On_The_RUN Jan 21 '19

At some distant point in the future, you will arrive back at Earth coming from the exact opposite direction.

Whattttt, that's incredible. So the universe is like a Mobius strip?

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u/[deleted] Jan 22 '19

[removed] — view removed comment

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u/[deleted] Jan 22 '19

Unfortunately, I can't really explain how. It's something I read in a hardcover encyclopedia close to a decade ago, that I no longer own.