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James Webb Space Telescope reveals that most galaxies rotate clockwise

smithsonianmag.com

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Re: James Webb Space Telescope reveals that most galaxies rotate clockwise

#201

Post by kmoser »

keyle wrote: post #9

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?

Dumber question: would a galaxy that appears to spin clockwise appear to spin counter-clockwise when viewed from the other side? Does this imply that the real question is why galaxies' relative orientations seem to favor more spinning in one direction than the other?

Re: James Webb Space Telescope reveals that most galaxies rotate clockwise

#202

Post by SkyBelow »

Contax wrote: post #135
vlovich123 wrote: post #126

Earlier quoted context omitted.

But the universe isn’t spherical. I’m not sure I understand this hypothesis as explained.

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.

It is often presented this way because models generally mix up the observable universe and the universe. One key notion is that we are at the center of the universe. Not the Milky Way, not the Sun, Earth is. Yet we know that Earth isn't at the center, so what is that? Because it is defined as our ability to travel from where we are at. Each of us could be considered at the center of our own observable universes, but this is a distinction we don't make because they overlap so closely that we don't have tools with the precision to tell them apart. I would guess that even aliens on the other side of Milky Way have an observable universe that overlaps so closely with our that they are equal to whatever level of precisions our tools allow for. Once you get to someone in a different galaxy, especially one that is moving away from us and not closer, then they have a different observable universe.

But then, what is the universe? One way to think of it is to imagine that every galaxy has at least one intelligent species with their own observable universe. The universe is the sum of all observable universes. The very nature of how to sum them together, what it means to combine multiple sets of thing which include items that don't exist relative to other items in the set, is a question we can't really answer yet. Because of this, even a question like the size of the universe is unknown, and even the question of if more of the universe exists outside of the observable universe isn't simple to answer and gets into the nature of what it means to exist. If someone exists in the universe, but not in the observable universe, it becomes an instance of Russell's Teapot.

Re: James Webb Space Telescope reveals that most galaxies rotate clockwise

#203

Post by irrational »

soulofmischief wrote: post #173
nashashmi wrote: post #80

Earlier quoted context omitted.

“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.

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

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.

Re: James Webb Space Telescope reveals that most galaxies rotate clockwise

#204

Post by SkyBelow »

vlovich123 wrote: post #183
pests wrote: post #133

Earlier quoted context omitted.

But the observable universe roughly is.

The observable universe is an illusory artifact of being an observer traveling at less than the speed of light. A constant distance in every direction is a sphere. That tells us nothing about the actual structure of the universe. In other words, your observable universe is different than mine and that's both spheres we're in the middle of. That suggests the universe itself probably isn't a sphere.

Is it an illusory artifact or is it all that exists? If it can't be observed, it can't be tested, it can't be verified in any way or ever interacted with, then isn't it just an instances of Russell's Teapot and thus does not exist? What does it mean for science if existence isn't a binary property or one that we set as a truth yet is entirely untestable?

Re: James Webb Space Telescope reveals that most galaxies rotate clockwise

#206

Post by peterburkimsher »

jenadine wrote: post #200
peterburkimsher wrote: post #198

Earlier quoted context omitted.

We're in the centre of the observable universe. The observable universe is the only true sphere. The observable universe is expanding into the unobservable universe. What would be interesting is to run a diff on the cosmic microwave background and the pictures from the James Webb space telescope to figure out where the true centre of the universe is, and derive the poles from there.

> The observable universe is expanding into the unobservable universe. Is that so? My understanding is that it doesn't expend into something. And that it expend so fast that the edge of it becomes unobservable.

Space and time are related, and expanding rapidly since the Big Bang (though there was a time in the early universe when the expansion rate was faster).

https://cds.cern.ch/images/CERN-HOMEWEB-PHO-2022-023-1

Observing the edge is effectively looking back in time, to see the conditions of the universe closer to the time of the Big Bang.

New telescopes keep expanding that edge, and new particle colliders (such as those at CERN or Fermilab) keep "bashing 2 rocks together to make fire" - recreating the conditions of the Big Bang to see what comes off.

What I'm not sure about is whether the speed of light (assumed to be constant) is correlated with the size of the observable universe. Perhaps a physicist could shed some light on that question. Relativity means that galaxies that are moving at the speed of light away from one another (one travelling at c, another travelling at -c) have a relative velocity of higher than the speed of light (|c| + |-c| = 2c).

There's also the theory of the One Electron Universe, which I quite like (though that reveals my bias as an electronic systems engineer). Perhaps what we see is the One photon universe. https://en.wikipedia.org/wiki/One-electron_universe

Hopefully this rambling makes sense to someone!

Re: James Webb Space Telescope reveals that most galaxies rotate clockwise

#207

Post by pixl97 »

SkyBelow wrote: post #204
vlovich123 wrote: post #183

Earlier quoted context omitted.

The observable universe is an illusory artifact of being an observer traveling at less than the speed of light. A constant distance in every direction is a sphere. That tells us nothing about the actual structure of the universe. In other words, your observable universe is different than mine and that's both spheres we're in the middle of. That suggests the universe itself probably isn't a sphere.

Is it an illusory artifact or is it all that exists? If it can't be observed, it can't be tested, it can't be verified in any way or ever interacted with, then isn't it just an instances of Russell's Teapot and thus does not exist? What does it mean for science if existence isn't a binary property or one that we set as a truth yet is entirely untestable?

From all we can tell at this point is the universe is flat.

https://en.wikipedia.org/wiki/Shape_of_the_universe

Re: James Webb Space Telescope reveals that most galaxies rotate clockwise

#209

Post by q_andrew »

rob74 wrote: post #105
vincnetas wrote: post #67

But rotation direction depends on the observer. If i see galaxy spinning clockwise, this means someone observing galaxy from behind it sees it rotating counter clockwise. So are we just located so in the universe that we see 2/3 spinning clockwise and another counter?

It just occured to me that "rotation direction" is a pretty coarse measurement. Actually, you could look at the angle of a galaxy relative to ours, where (let's say) 0° is viewed exactly from "above" (rotating clockwise), 180° is viewed exactly from "below" (rotating counterclockwise), 90°/270° is viewed side-on etc. How about some stats based on this parameter?

This is actually why rotational math is more complicated in 3d than you would expect. It's something game developers get used to, because accessing and modifying a rotation requires knowing what the orientation is relative to a fourth axis. That's what a quaternion is. In the situation of this story, it's in reference to the milky way's vertical axis.

Re: James Webb Space Telescope reveals that most galaxies rotate clockwise

#210

Post by lostmsu »

like_any_other wrote: post #137
tomr_stargazer wrote: post #111

Earlier quoted context omitted.

I think this may be a subtle reference to what is usually called "relativistic beaming" or "Doppler beaming" [0], though I normally associate this effect with matter that is moving quite close to the speed of light. [0]: https://en.wikipedia.org/wiki/Relativistic_beaming

perihelions [1] phrased it best - a galaxy spinning clockwise is just the mirror image of one spinning counter-clockwise. So why should mirroring change brightness? I don't really understand why Doppler beaming would cause this (though one of the papers did also mention it). The other question is - what does the rotation of our own galaxy have to do with it? Let's keep the Solar system as is, and mirror the rest of t…

This is only obvious when you yourself are not moving on a curved trajectory.

In GR curved trajectories lead to "weird" observations. For instance, I'd expect the side of the remote galaxy that is closer (visually, for you as an observer) to the center of your galaxy to be gravilensed slightly more than the other side. Because the effect is non-linear, it does not just compensate when sides are reversed.

P.S. Not claiming this has any significant effect on the described phenomenon, just that mirror symmetry does not apply.

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