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352 points instagraham | 1 comments | | HN request time: 0.208s | source
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keyle ◴[] No.43533500[source]
Potentially a very dumb question, but seeing the difference between cyclones and hurricane on earth (clock-wise, anti-clock-wise)...

Does it mean that we are, potentially, on one of two poles(?) of the observable universe, if we're observing most galaxies around us rotating a certain way?

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tiffanyh ◴[] No.43534000[source]
My own dumb question …

How does cyclones/hurricanes relate to being “on one of two ‘poles’”?

Do you mean hemisphere?

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jeffdn ◴[] No.43534491[source]
If all of the galaxies we see rotate the same way, are we “looking down” from a pole and seeing only those with the same rotation we have, as opposed to a more equatorial view that would be evenly split.
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vlovich123 ◴[] No.43535156[source]
But the universe isn’t spherical. I’m not sure I understand this hypothesis as explained.
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Contax ◴[] No.43535422[source]
This along blows my mind: I picture this bin bang and everything expanding from that point and... that everything is now a sphere. In my mind. But it isn't? Yes, I know next to nothing but love thinking about all of this.
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jon_richards ◴[] No.43536092[source]
Picture an infinitely long piece of elastic. Now stretch that elastic.
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bigmadshoe ◴[] No.43536662[source]
Isn't this a 1d or 2d simplification?
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jon_richards ◴[] No.43537424[source]
Yes, 1d. But it's easier to go from a strip to a sheet to a block than trying to imagine an infinite block from scratch.

The important part is that at any given point on the elastic strip, both sides are getting further away. Everything else is getting further away.

You might think if A-B-C-D are points on the tape and A-B are expanding and C-D are expanding, then B and C must be squished together, but the distance between them is also expanding. You have infinite elastic, but you also have infinite room to stretch it (even along the direction it already occupies). You now have A--B--C--D.

It's tempting to think about that stretch from the point of view of the floor/table beneath the elastic, in which case some parts of the elastic move faster than others as they stretch, but if you always think from a point on the elastic, then the speed of the rest of the elastic depends on how far away it is. Stuff twice as far away moves away twice as fast. Stuff infinitely far away moves away infinitely fast. That's true for every point on the elastic. No bunching up.

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1. kirubakaran ◴[] No.43537540[source]
I usually just imagine an n-dimensional space and then substitute n as needed