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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

#301

Post by SkyBelow »

vlovich123 wrote: post #293
SkyBelow wrote: post #288

Earlier quoted context omitted.

>Just because something is untestable today doesn’t mean it will be for all time. This is generally true, but such ideas are kept outside the realm of science until they are. In this case specifically, all our knowledge points to this remaining untestable as it would require FTL travel which is on par with violating conservation of energy or time travel. It even allows solving the halting problem (Turing machine in t…

> Do they? The nature of the observable universe is that, if you can communicate with someone else, any information they can receive and pass on to you is part of your observable universe as all information travels at the speed of light or slower. If they can receive information and cannot pass it on to you, they are not part of your observable universe any longer and no longer exist (exception if FTL interactions ar…

>It says nothing about repeaters. If someone id at the edge of your observable universe they could still send you a message. They’re observable universe would necessarily include light that wouldn’t reach you due to expansion.

I don't think it does once accounting fully for relativity (and assuming perfect sensors, so the idea of information being too redshifted to be detected isn't a factor until that information no longer exists within the universe, and immortality of participants, and near light speed travel).

Say Alice and Bob can communicate X years apart at near C speed. At any time, Alice can jump on a spaceship and reach Bob in ~X years. Therefore, anything in Bob's observable universe at that time counts as also being in Alice's observable universe.

If the distance is so far apart that one day space will expand too fast, then there is a moment where Alice stops being able to travel to see Bob ever again. At that moment, Bob's observable universe is now distinct for Alice's, but they also can no longer communicate.

Bob could get on a spaceship going near C away from Alice and access information that is outside of Alice's observable universe, but Bob only crosses that barrier when he moves far enough away from Alice that he exits her observable universe. (Technically I think you get some sort of infinite sphegettification of Bob leaving as he crosses Alice's observable universe's event horizon, where he never fully leaves and sends back photos that become more and more red shifted until their wavelength equals the diameter of the observable universe.)

So Bob has an observable universe that is different from Alice's, but it is predicated on him exiting from Alice's observable universe to access it. Either he accesses it and stops existing to Alice, or he doesn't access it and eventually it falls out of what he can possible access. The only part he can access and still communicate back to Alice is the part within Alice's universe. It is a bit like a superpower to turn invisible only when no one is looking... sorta kinda...

Given enough time, Alice and Bob either drift together until they clearly share the same observable universe, or eventually drift apart to the point expansion of space shifts them into two separate unrelated observable universes and they stop existing relative to each other.

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

#302

Post by kadoban »

bencyoung wrote: post #296
thunder-blue-3 wrote: post #75

Earlier quoted context omitted.

I've been following this news for the past couple of weeks-- in essence your statement is what they are hypothesizing, and that the "something at the center that unites the two poles" might be that we are within a black hole. https://en.wikipedia.org/wiki/Black_hole_cosmology for the curious.

From what I remembe of Undergrad physics this isn't actually possible. According to GR, within an event horizon, space-like pths become "time-like" which effecitvely means the singularity is unavoidably "in the future". No matter how big a black hole is, you can't just drift around inside it as literally all paths lead downward (hence even light not escaping) If you were inside a black hole you wouldn't be able to se…

All paths _eventually_ lead downward. Is there any limit to how long? Can't we just be near the outside of the blackhole and can't see the doom yet?

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

#303

Post by namaria »

MichaelZuo wrote: post #287
namaria wrote: post #272

Earlier quoted context omitted.

I don't get it, why did you ask for clarifications about why this was not expected if you're just going to be adamant it should have been expected? Is it really your honest position that everyone has been doing cosmology wrong and you would have known better?

I didn’t ask for clarifications… I asked how it followed… Are you sure you understood the comments completely? It’s my honest opinion that anyone assuming away phenomena like turbulence, without credible proof, cannot be relied upon to have accurate insights. So yes whenever I do have better insights, than by definition that’s more than 100% of the population who do not.

Right. I guess I did not understand your comment at all then. I am sorry I engaged.

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

#304

Post by joe_the_user »

iainmerrick wrote: post #277
joe_the_user wrote: post #266

Earlier quoted context omitted.

Just to be clear, it's not fine at all in any "this is a fine physical theory". A statistically unlikely arrangement of cosmic objects relative to earth only - earth in particular, violates not just the properties of the big bang but "the cosmological principle" and common sense. It's a garbage theory, a headline that makes a math person just have a "how stupid do they expect the average person to be" reaction.

No, I don't think you have this right. There was no physical theory claimed, just a very surprising observation (though of course it turns out to be bogus). If it were true it would require an incredible explanation, but that's not at all the same as just proposing an outlandish theory with no motivation. If you take the approach you describe, I think you'd have incorrectly dismissed the observation that distant cont…

TL;DR; all your analogies are less extreme than the claimed observation because they don't violate the principle that physical laws apply uniformly throughout space/time.

Theory or data/observation is a sort of layered thing. The lowest data level is the data that the Webb or whatever telescope gets, then you have the theory that what's being represented in galaxies and you have all suppositions of standard cosmology and in that you have a posited theory that galaxies as viewed from earth rotate in a "given direction".

The thing about this theory/observation/whatever is that it's a pattern that, if true, would only be visible on earth (or in vanishingly small area relative to the claimed area of the pattern). If such a thing were happening, it wouldn't just contradict current physical laws. It would contradict the paradigm science has had since Newton that physical laws apply uniformly throughout the cosmos and especially that the earth isn't the "center" of the universe. The observation of continents fitting together or violations of parity conservation aren't analogous because they involve things that can be meaningfully observed anywhere.

All this is to say "extraordinary claims require extraordinary evidence". As far as investigating. I could or someone could, spend the effort needed to investigate this. But science actually should have one level of claim+evidence that's "interesting, let's investigate" and another that's "oh dear, that's really crank stuff and you'd need to truly vast evidence before I'd even look". Other science would be overwhelm by bullshit.

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

#305

Post by hnaccount_rng »

MichaelZuo wrote: post #227
hnaccount_rng wrote: post #217

Earlier quoted context omitted.

I think you are misunderstanding the point being made: The _only_ random chance that is part of current models is "quantum uncertainty at big bang time" and we can give upper bounds for the variations that can be explained from that. So what's really being said here is "We found a significantly larger discrepancy between Milkyway-corotating galaxies and Milkyway-counterrotating galaxies than can be explained by ~init…

That doesn’t make sense, they can’t be assumed to have behaved like ideal gasses, thus turbulence alone can cause significant uncertainties. Let alone all other possibilities combined.

No it can't. Turbulence does not introduce net-angular momentum. It just (re)distributes it. And the scale on which that "mixing" can happen is limited (essentially the speed of sound is smaller than the expansion of the universe in the early universe). So on large enough scale, it (~any vector value) must be add up to ~zero (up to the initialisation uncertainties). Or one of our fundamental assumptions is wrong. And that's why this is so interesting

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

#306

Post by vlovich123 »

SkyBelow wrote: post #301
vlovich123 wrote: post #293

Earlier quoted context omitted.

> Do they? The nature of the observable universe is that, if you can communicate with someone else, any information they can receive and pass on to you is part of your observable universe as all information travels at the speed of light or slower. If they can receive information and cannot pass it on to you, they are not part of your observable universe any longer and no longer exist (exception if FTL interactions ar…

>It says nothing about repeaters. If someone id at the edge of your observable universe they could still send you a message. They’re observable universe would necessarily include light that wouldn’t reach you due to expansion. I don't think it does once accounting fully for relativity (and assuming perfect sensors, so the idea of information being too redshifted to be detected isn't a factor until that information no…

It’s not possible for Alice and Bob to be within each other’s light cones but observe galaxies that aren’t in the other’s light cone? That seems wrong - there are galaxies that disappear from our light cone due to the expansion of the universe and they have neighbors that are still visible to us which would imply that the neighbors can still see the galaxy that became invisible to us.

I’m willing to concede I don’t know enough about the actual math of cosmology and relativity to say. How certain are you in your reasoning? I’m willing to admit either case could be possible and neither is a testable prediction at this time but maybe my first principles reasoning is outright flawed?

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

#307

Post by MichaelZuo »

namaria wrote: post #303
MichaelZuo wrote: post #287

Earlier quoted context omitted.

I didn’t ask for clarifications… I asked how it followed… Are you sure you understood the comments completely? It’s my honest opinion that anyone assuming away phenomena like turbulence, without credible proof, cannot be relied upon to have accurate insights. So yes whenever I do have better insights, than by definition that’s more than 100% of the population who do not.

Right. I guess I did not understand your comment at all then. I am sorry I engaged.

Then why stick around for another reply that can only detract, or at best be neutral…?

It seems impossible for this to add to your argument.

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

#308

Post by MichaelZuo »

hnaccount_rng wrote: post #305
MichaelZuo wrote: post #227

Earlier quoted context omitted.

That doesn’t make sense, they can’t be assumed to have behaved like ideal gasses, thus turbulence alone can cause significant uncertainties. Let alone all other possibilities combined.

No it can't. Turbulence does not introduce net-angular momentum. It just (re)distributes it. And the scale on which that "mixing" can happen is limited (essentially the speed of sound is smaller than the expansion of the universe in the early universe). So on large enough scale, it (~any vector value) must be add up to ~zero (up to the initialisation uncertainties). Or one of our fundamental assumptions is wrong. And…

Can you link the proof for these claims?

I don’t see any obviously titled ones on Google Scholar, such as proving it’s impossible for turbulence to “introduce net angular momentum”.

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

#309

Post by hnaccount_rng »

MichaelZuo wrote: post #308
hnaccount_rng wrote: post #305

Earlier quoted context omitted.

No it can't. Turbulence does not introduce net-angular momentum. It just (re)distributes it. And the scale on which that "mixing" can happen is limited (essentially the speed of sound is smaller than the expansion of the universe in the early universe). So on large enough scale, it (~any vector value) must be add up to ~zero (up to the initialisation uncertainties). Or one of our fundamental assumptions is wrong. And…

Can you link the proof for these claims? I don’t see any obviously titled ones on Google Scholar, such as proving it’s impossible for turbulence to “introduce net angular momentum”.

I don't have anything more than Newton's third law for you and that its effects also hold in general relativity. The "far away parts of the universe are disconnected" is from my astrophysics courses back in university and the number of lectures to the cosmic microwave background, mostly coming from people discussing the Planck mission.

But.. no, I don't have a convenient citation for you. And at least for the "angular momentum is conserved thing", I'd be surprised if you'd find a google scholar paper, this is early GR

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

#310

Post by SkyBelow »

vlovich123 wrote: post #306
SkyBelow wrote: post #301

Earlier quoted context omitted.

>It says nothing about repeaters. If someone id at the edge of your observable universe they could still send you a message. They’re observable universe would necessarily include light that wouldn’t reach you due to expansion. I don't think it does once accounting fully for relativity (and assuming perfect sensors, so the idea of information being too redshifted to be detected isn't a factor until that information no…

It’s not possible for Alice and Bob to be within each other’s light cones but observe galaxies that aren’t in the other’s light cone? That seems wrong - there are galaxies that disappear from our light cone due to the expansion of the universe and they have neighbors that are still visible to us which would imply that the neighbors can still see the galaxy that became invisible to us. I’m willing to concede I don’t k…

It is about when they are or aren't in the light cones. If we remove relativity for a moment and define some time T=0, then Alice and Bob do see different things. The thing is that at 0, Bob and Alice aren't in each other light cones. Future Bob is in Alice's light cone and future Alice is in Bob's light cone, but at current they aren't. So you in the case of Alice, it is a question of what is in Bob's light cone.

There is also the matter of possible verses actual light cones. Assuming we had a ship that could go near C, imagine Alice doing three things. Alice v1 stays home. Alice v2 goes racing off near C to the left. Alice v3 goes racing off near C to the right. Each of these will have different light cones, but Alice v0 who hasn't made a decision could make any one of these decisions and thus all three light cones are in her possible light cones if she chooses to pick each action. Eventually each Alice will be so far away from each other that expansion of space splits their light cones into entirely separate ones from that point on.

>How certain are you in your reasoning?

Not at all. This is just based on my understanding of the very basics. The reason I'm sticking to it like I am is because, if I'm wrong and someone can point out where, it becomes a really good learning opportunity for me. And if I'm not wrong (at least given the layman level of detail of the conversation), the better I can explain my reasoning the better someone else might gain new ideas from it.

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