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Spooky Alignment of Quasars Across Billions of Light-years (eso.org)
225 points by Zomad on Nov 20, 2014 | hide | past | web | favorite | 70 comments



>"The new VLT results indicate that the rotation axes of the quasars tend to be parallel to the large-scale structures in which they find themselves. So, if the quasars are in a long filament then the spins of the central black holes will point along the filament."

Though I have no real idea what I'm talking about...

This feels intuitive to my mental picture of the universe.

The description of this large scale structure and the expansion of the universe has always put me in mind of watching the patterns form and reform from drips in a soapy sink or an elastic fabric being pulled apart.

In both cases, you end up with these big expanses bordered by dense stringy areas. That the motion of the stuff that snaps / shears / collapses or whatever into these strings and knots would be aligned seems perfectly logical.


Conservation of angular momentum. I don't see this as all that shocking. If you consider that the universe is growing (or at least it appears to be and to the best of our knowledge), and that therefore at some point the matter that now comprises these quasars was quite probably part of a single coherent system, say, an earlier galaxy, which would have had angular momentum - all this is showing is the angular momentum of the structure which birthed the quasars. Which is neat.

Simple version: imagine you have a long pole which is spinning, fast. Then imagine a ninja comes in and slices the pole up, perpendicular to its axis, so you've got 20 short poles. The 20 short poles continue to spin on the same axis as the original long pole. If those poles are in the vacuum of space with nothing slowing them down, they will continue to spin in the same way for a very, very long time. They might wobble a bit (precession), which explains why the poles aren't all perfectly aligned in this data.


Our intuition does a very poor job of answering questions like this (well, almost any questions, really) and we can spend a lot of time fooling ourselves that the way the universe actually is "makes sense" in some intuitive way. It doesn't. If it did, we'd have had correct physics in 1687 BCE instead of 1687 CE.

One way to test this is to ask yourself what your intuition tells you before you know the answer. You'll mostly get it wrong, unless you have formal training in the field. Intuitive "explanations" are only good after the fact, and even after the fact can be misleading and problematic, as the one you bring up here is.

The universe as a whole (very probably) has zero angular momentum. There are consequences on the large scale if this is not the case that we'd probably have detected by now. So early star formation, including quasar formation, happened in a hot zero-momentum gas cloud that filled the expanding universe. That is the structure that birthed the quasars. That means that while there may well have been local eddies, there was not any overall rotation to the gas. So why would quasars that formed in distant parts of that gas have their axes aligned in the same direction?

Short version: your mental model of the early universe is not accurate, so your intuitive explanation doesn't actually explain the phenomenon under study. Simply because it "makes sense" of the data does not make it useful. In particular, you've assumed a counter-factual.

The reason why cosmologists are surprised by these results is because they have a better understanding of the early universe, and know that there is no known mechanism to align the rotational axes of these objects. They are now wondering what that mechanism might be. Global angular momentum is one possibility, but it is far, far down on the list because it is contradicted by a lot of other data.


Why there's angular momentum - turbulence.

I do have formal training in the field, if a masters in physics counts, with a specialisation in cosmology and astrophysics.

My thesis was oriented around computational simulations of the early universe, using fluid dynamics.


> Our intuition does a very poor job of answering questions like this (well, almost any questions, really) and we can spend a lot of time fooling ourselves that the way the universe actually is "makes sense" in some intuitive way. It doesn't. If it did, we'd have had correct physics in 1687 BCE instead of 1687 CE.

This is excellent.


> The universe as a whole (very probably) has zero angular momentum.

Relative to what? Or do you mean the observable universe relative to the CMB?


> Then imagine a ninja comes in and slices the pole up, perpendicular to its axis, so you've got 20 short poles.

Why would you expect the ninja to do this? Why would you expect large-scale structures of the universe to form parallel to the quasars' axes?

As far as we can tell, the alignment of planetary systems in the Milky Way are random.[1]

[1] http://astronomy.stackexchange.com/questions/546/why-is-our-...


> Conservation of angular momentum. I don't see this as all that shocking.

What is fascinating is that the angular momentum seems to be roughly aligned with the underlying "membranes", as if the voids themselves are actually expanding.


> A correlation between the orientation of quasars and the structure they belong to is an important prediction of numerical models of evolution of our Universe.

This was predicted so there must be some understanding of how it works. Doesn't seem that spooky.


Yes, it looks rather like one more confirmation that the expansion actually happened.


I'd guess it's referring to Einstein's "spooky action at a distance"


No, it's not. Spooky action at a distance refers to phenomena arising at the quantum level. The scale difference between that and alignment of the rotations of quasars is getting near the largest observable scale difference there can be. Which, itself, is kinda satisfying :).

The spookiness here is of similar nature as the spookiness how the eurasian continental plate seems to fit snugly with the american one although they are now quite far apart - i.e. we should be able to figure out which past events led to the current configuration.

I would call this result 'really cool' rather than 'spooky' but neither of those are very specific terms ;)


You're right, but the journalist probably selected that word for the 'Science!' association with the QM term.


That is what I thought to, but I do not see anything in this article that hint as some sort of spooky action at a distance.


Out of "93 quasars", "19 of them found a significantly polarized signal." "Results indicate that the rotation axes of the quasars tend to be parallel to the large-scale structures in which they find themselves."

Do quasars that aren't parallel to their large-scale structures not have a significantly polarized signal? Maybe interference from the structure or a weaker signal because of their alignment?


If we wind the clock back far enough couldn't we explain this if the original matter that went on to form the black holes originated from blobs of matter that were affected by the same local forces? Then we just wait long enough and things that were next to each other in the distant past now reside long the dark mater filaments? Given the angular momentum of these suckers I'd guess that it is pretty hard to significantly change their axis of rotation even over a couple billion years.


I don't see how that explains the axes aligning along the filaments. It might explain the axes being aligned.


“The first odd thing we noticed was that some of the quasars’ rotation axes were aligned with each other — despite the fact that these quasars are separated by billions of light-years,” said Hutsemékers.

This seems like it might be a breakthrough result.


"So, if the quasars are in a long filament then the spins of the central black holes will point along the filament."

the filament formation means the matter moving inward toward the virtual "centerline" (the term is used here pretty loosely obviously) of the filament. As this movement isn't perfectly aligned/balanced there is a total nonzero angular moment of the matter kind of orbiting around the "centerline" - the vector of the moment pointing along the "centerline". The bigger the object inside the filament, the more [statistically] expected its angular moment to be aligned with the total angular moment of the filament.


what? Can I have this translated "for dummies" also?


Imagine an airplane at an airshow. It flies past with a smoke generator belching out smoke, leaving a rough trail behind it that churns and deforms. It's roughly a long tube of churning particles.

Now take this shape into space and make it enormously large. All of the particles in this long, stringy, tube-shaped arrangement attract each other gravitationally, so the tube starts to tighten. The particles around the outside of the tube are pulled back toward the other particles in the tube, which generally pulls them toward the centerline of the tube. Of course, each particle will have its own momentum, so if you looked down the centerline of the tube, you'd see some particles heading a little to one side of the centerline, some heading toward the other. Looking down that centerline, you'd see some particles tending to orbit around the center in a clockwise direction, some others going counter-clockwise.

It's very unlikely that there would be the same number of particles going clockwise around the centerline as counter-clockwise. Just randomly, there would very likely be somewhat more particles going one way than the other, so eventually the tightening tube would seem to be rolling around its centerline in the majority direction.

What trhway is saying is that any really big, dense clusters of particles in the tube would probably have roughly the same characteristics as the whole tube they were a part of. The particles rotating around the center of a large, dense cluster of particles in the tube would tend to resemble the rest of the tube statistically, so they would tend to roll in the same direction as the tube itself, meaning the axes of rotation of these big chunks would tend to be parallel with each other and parallel to the centerline of the tube.


>What trhway is saying is that any really big, dense clusters of particles in the tube would probably have roughly the same characteristics as the whole tube they were a part of. The particles rotating around the center of a large, dense cluster of particles in the tube would tend to resemble the rest of the tube statistically, so they would tend to roll in the same direction as the tube itself, meaning the axes of rotation of these big chunks would tend to be parallel with each other and parallel to the centerline of the tube.

yep. Just to add that as those chunks has already clumped close together they are forced to rotate much faster to preserve their share of angular momentum - thus we see rotating quasars on the background of seemingly (in our observation timescale) static filament.


:) imagine say 2 objects in space moving toward each other like 2 cars in the opposite direction lanes. Imagine there is a long metal bar across the road such that these 2 cars hit it simultaneously from their respective directions - the bar will rotate - i.e. the combined system of these 2 cars has angular moment. In space there is no bar, instead there is gravitation - these 2 cars would get clumped together (on the "divider" between the "lanes") due to gravitation pull between them. The resulting clump will rotate as result of the angular moment preservation. Now if we expand the model to billions of billions of rocks and gas clouds which form the filament ... :)


Ignoring the fact we can't get out there, does this give us a neat method of orienting ourselves when travelling through these vast distances?


Even today, the celestial co-ordinates we use are based on references to the positions of extra-galactic radio sources. See for example ICRF (1)

(1) https://en.wikipedia.org/wiki/International_Celestial_Refere...


At first glance it seems so, but afterwards it still seems like nothing has changed for the space travellers. Maybe the picture gives an illusion of a 2D birds eye view hence looking simpler than the reality.


This is not as spooky as what I was expecting. Maybe if all of the quasar axes pointed at us...


Well, the ones we can see are! They're very very very distant objects that are very very bright, but they mostly emit along their axes. So, we can only detect the ones that are pointing at us.


Hmm. If the only ones that we can see are pointing at us then it seems really unspooky that we should be able to look at quasars that are very far apart and see that they all appear to have the same orientation. The ones which have any other orientation are being filtered out. I'm guessing the astronomers must have somehow accounted for this though? Seems like if all of the quasars really were aligned then there would appear to be a lot more quasars when observing in a direction which was parallel to the common direction along which they emit light.


This is not an observation of axes visible from Earth (since that is obviously biased):

The team could not see the rotation axes or the jets of the quasars directly. Instead they measured the polarisation of the light from each quasar and, for 19 of them, found a significantly polarised signal.

Even if it had been the case that they were directly observing axes visible from Earth, those wouldn't appear to be parallel unless they were also proximate in the sky.


More wild speculations: could it be, that these quasars are somehow connected through some yet unknown medium, that allows such behaviour? I mean it's difficult to sync clocks on several computers in the same building, how the hell could massive, hulking rotating blobs of pure gravity billions of light years apart "sync"?


Because in some rough sense, at one time all the blobs, filaments, etc. were close together and, there, got coordinated.


Those sneaky assholes...


The Moon is in sync with the Earth. By the mechanism of Tidal locking.

So, there might be some possibilities.



If you randomly sampled a set of 93 dice floating in space from a set of 200,000, what are the odds that 20 of them are closely aligned along the same axes?

Is this a fair analogous question?


Isn't this on (way smaller) scale how the Solar system works? The spin of the planets and their axes are similar and mostly aligned?


Could this be the sign of a larger type of object in the cosmos? That would be neat.


Dumb question alert. Could an advanced civilization have done this? Perhaps to collect power?


Not answering your question, but I expect it would take a ridiculous amount of energy to change the angle of rotation on these things.


Sure. A dumb civilization could have done it too, perhaps as something to do with crystals or the Zodiac.

But in all seriousness, Occam's Razor is a great tool here. So far, every cosmological problem we believe we've figured out has occurred due to natural processes. There is very likely something we don't know about large scale structures (an understatement!).


In all seriousness, civilizations, dumb or not, are natural processes. There is very likely something we don't know about advanced civilizations.


I guess another dumb question; what does Occam's Razor say about the Fermi equation?


A couple possibilities that I'm aware of:

* All intelligent life goes extinct before achieving interstellar colonization, or is content to remain in their home stellar system.

* We are in the first generation of life in the galaxy capable of achieving interstellar colonization, due to the time scales required for sufficient heavy elements and evolutionary complexity to arrive.


To the down voter. If you think an advanced alien civilization is out of hand then why does SETI exist? Why did we put messages on voyager?


"Resist complaining about being downmodded. It never does any good, and it makes boring reading."

-- https://news.ycombinator.com/newsguidelines.html


I wasn't complaining. I just wasn't sure how else to address a rebuttal since people often downvote to disagree.


You’re not downvoted because you suggested the existence of aliens in general. Sure, we all hope that there is intelligent life somewhere else in the Universe or even in our own galaxy. But that doesn’t mean that every cosmological mystery we find we’ll attribute it to some advanced civilization.

Besides, even if this was the works of some super duper advanced civilization what difference does it make? Our quest is to explore and learn new things, whether they were made by nature, God, or any freaking alien out there is irrelevant.


SETI exists for that tiny, tiny chance that in the few years (very, very, very few) we look at data, the Earth is receiving transmissions from a remote part of the universe. Voyager's messages are far more likely to make contact with an alien species, since they'll be around effectively forever. It's just a matter of whether that happens while we're still in existence.


Voyager's won't reach the nearest star before 40,000 years, but, dunno, are any of the two actually aimed at any neighbouring star? I mean, come one, having a Voyager pass by some anonymous star at 170 light years of distance in 1,2 million years, and never come closer than 2650 AU to the star, what's the chance of actually detecting it by ET - even if an advanced civilisation is (will be) watching from one of its planets. It's tiny and, by the time it arrives, even the radioactivity levels will have dwindled to nothing. The only things that would make it stand out is it's speed, and the fact it's made of metal. They would need a very advanced radar, capable of detecting tiny masses of metal at enormous distances. Then, to investigate it, they would basically have to go grab it - but would you justify hunting for any chuck of metal transiting by the Oort cloud - what if it were just a piece of debris from an asteroid?!


But you don't know what advances would happen in 40,000 years, that too on another solar system. Maybe alien kids would be playing in their back-yard beside their Oort cloud equivalent and might check out Voyager just for fun.


Seems far more likely that in 40k years, humans will have discovered the ability of interstellar travel. Heck, at that point we could go out and fetch Voyager 1 ourselves before it comes within 1.6 light years of AC+79 3888. If we can't in 40k years, it's likely not possible that we'll ever leave this solar system. It could be that's it's just not physically possible. But more likely, do we survive long enough to develop that technology?

I've always viewed the Golden Record as a way to make humanity feel better about its future. The need to leave a legacy behind is core to who we are, and that's exactly what we did with those two discs. We left something behind that will survive for 1 billion years, with the infinitesimally small hopes that someone will find it. But, it makes us feel good.


This is a related effort http://en.wikipedia.org/wiki/KEO


Wouldn't common interpretations of the Fermi equation argue that it's not a tiny chance?


Man, you just have to ignore the downvotes. They really are inconsistent and meaningless.


The golden ratio at work.


"We apologise for the inconvenience"


Bad title.


Another severe blow to the cosmological principle.


No, because the quasars weren't aligned with each other globally (cosmologically), it appears they are aligned with whatever structure they are embedded in at large scales. I think the term is a filament, but I'm not sure.

If every quasar wherever we looked was aligned such that their axes of rotation were parallal, that would be a huge blow to the cosmological principal. Or more spookily, suppose all of the quasars studied were oriented with their poles lining up to some point in the universe. A good hint that some God created the universe for us, for example, would be for every single quasar's axis of rotation to be pointing at the earth.

But those things do not seem to be the case, and the cosmological principal appears to hold. Look at any corner of the universe, and quasars point in an arbitrary direction. Look at another corner, and they point in a different arbitrary direction. Zoom out, and now there is no cohesive direction. Homogeneity is preserved at scales much smaller than the largest structures we've observed, because the chains of quasars are themselves much smaller than the filaments and other super-structures that snake through the observable universe.


The principle is meant to apply only at a sufficiently large scale. If any particular scale goes against the principle, one can enlarge the scale to see if the principle still applies.


That still sounds like a blow to the meaningfulness or usefulness of the principle.


Why would it? If you enlarge the scale and find that the principle applies, it's useful.


And if all else fails, just scale out further... until you're effectively outside the universe.

Stipulate the presence of additional universes.

Then call the whole theoretical collection a "multiverse."

Voilà. We have no reason to believe this reflects reality, but it must be assumed...

...in order to preserve the Cosmological Principle.


genwin is talking about actual measurements, not speculation. Why are you throwing out a strawman?


You never get outside the universe, if it's infinitely large (and there's no evidence to the contrary).


Exactly


The alignments are exactly on the same scale of the filaments. It would be a contradition to the cosmological principle if, say, the alignments occurred only on one celestial hemisphere.


Is a line of basketballs all found to be spinning in the exact same direction more or less random than a line of basketballs spinning in random directions?

I know, I know. "Sufficiently large scale."

(lol)


Basketballs are not formed by gravity.

Edit: quote from the article:

“A correlation between the orientation of quasars and the structure they belong to is an important prediction of numerical models of evolution of our Universe. Our data provide the first observational confirmation of this effect, on scales much larger that[sic] what had been observed to date for normal galaxies,” adds Dominique Sluse of the Argelander-Institut für Astronomie in Bonn, Germany and University of Liège.

So clearly this was expected.




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