[nashashmi]

“The universe is an orb and that orb is rotating causing all the other stuff to spiral.” This was a long held theory of mine because I could not understand why a galaxy would spiral.

I think there is a men in black scene, where an alien is rotating the universe globe like a toy they are playing.

[rdtsc]

> This was a long held theory of mine because I could not understand why a galaxy would spiral.

I think in general it would be unusual if they didn’t rotate. Any large non-uniform mass of gas or rocks when colliding will induce some rotation. What is odd though is that for galaxies we see more of them spinning one way than another.

[soulofmischief]

Ok but what is making the universe spin? This kind of theory is turtles all the way down.

[irrational]

Is this getting into questions like "Where did the singularity come from?" and "What came before the singularity?". We don't have a way to answer these kinds of questions.

[soulofmischief]

My point is that it's not much helpful to say, "galaxies spin a certain way because the universe spins", because it shifts the problem without actually answering the "why". "Turtles all the way down" is a saying about such infinite regress. https://en.wikipedia.org/wiki/Turtles_all_the_way_down

And yes, I'm familiar with Dawkins' famous retort when someone asked how magnets repel things.

[thaumasiotes]

> And yes, I'm familiar with Dawkins' famous retort when someone asked how magnets repel things.

I'm not. I was unable to substantiate that anyone named Dawkins, Richard or otherwise, made or is popularly associated with a comment about magnets. What was the retort?

[soulofmischief]

I deeply apologize, it was late and I mixed up my Richards. :)

https://youtube.com/watch?v=36GT2zI8lVA

[eightysixfour]

Doesn’t it have to spiral? Think of the gravity well, anything not orbiting is just falling. The only things not racing towards the black hole at the center of the galaxy are the ones that are orbiting.

[nashashmi]

It can be directly sucked into the center. A spiral implies a lateral movement plus a centripetal force

[eightysixfour]

Right, I guess what I am saying is if it didn't spiral, it wouldn't be a galaxy for "long." It would just be a super massive black hole.

[lolc]

The trick to having a galaxy is for mass to fall towards the black hole and miss it all the time.