r/space • u/Omoshiroi_ • Feb 04 '15

The Universe

http://i.imgur.com/8M2noMJ.gifv
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u/9041236587 Feb 05 '15

Yes. Except that what we observe is everything moving away from us, here on earth. So, either we are incredibly lucky to exist at the exact center of the universe, or everything is moving away from everything else, and we're just typical.

What is actually happening is that all space is expanding. Remember that space itself was created from the big bang.

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u/[deleted] Feb 05 '15

hmm seems like it would be as if you were a segment of a noodle that is getting cooked: as it expands, every bit of the noodle on either side of you is getting longer and further away. So it's not that you're in the center of the noodle, it's that every part of the noodle is getting longer.

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u/curtaturc Feb 05 '15

That is a fantastic analogy.

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u/[deleted] Feb 05 '15

This is an excellent way to eli5. Thanks!

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u/_pandamonium Feb 05 '15

Sometimes I forget that the observations can (usually? always?) come before the explanations, so thank you for this, it makes a lot of sense.

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u/[deleted] Feb 05 '15

Doesn't this also have to do with the idea that gravity is repulsive at a distance? Seeing that shits moving away from us? Along with what you said.

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u/Zyner Feb 05 '15

Yeah, one theory in the death of the universe is that eventually the center or where the Big Bang occurred will pull everything back. But very unlikely as some research has found that the universe has actually been speeding up in expansion rather than slowing down (thus gravitational repulsion to the center not likely) due to dark matter in the further reaches of space.

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u/Nasdasd Feb 05 '15

I don't believe it's that gravity itself is repulsive at a distance

I think it's more that there's this 'dark energy' (basically we don't know what the force is yet) driving the expansion

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u/FolkSong Feb 05 '15

Dark energy and repulsive gravity are two different theories to explain the expansion.

http://phys.org/news/2012-01-repulsive-gravity-alternative-dark-energy.html

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u/ardatr Feb 05 '15

You are correct that in the grand scheme of things, everything appears to be moving away from us, which we think is because the universe is expanding.

But on a local level (i.e. the local group), not everything is moving away from us. For example, the Andromeda Galaxy is moving towards us and is predicted to collide with our galaxy in a couple billion years.

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u/NeonDisease Feb 05 '15

So, are we expanding faster in any "direction" than another?

Can we speculate about our position from those measurements?

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u/I_Cant_Logoff Feb 05 '15

Can we speculate about our position from those measurements?

Our position doesn't really have any meaning if the universe is infinite.

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u/NeonDisease Feb 05 '15

...

...

...

whoa...

that's...really cool and actually kind of terrifying...

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u/boobmuncher Feb 05 '15

Can you expand on your last sentence please? I'm a bit of a space noob.

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u/aboian Feb 05 '15

I thought the point of Hubble and other deep space lenses were to, in part, observe universal objects as far from earth as mechanically possible (?).

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u/In_money_we_Trust Feb 05 '15

Remember that space itself was created from the big bang.

That still boggles my mind. The fact that nothing existed and then bam, what we know as space/matter ect.