Planck reveals link between active galaxies and their dark matter environment

Planck reveals link between active galaxies and their dark matter environment
Gravitational deflection by quasar-hosting dark matter halos. Credit: David Tree, Professor Peter Richardson, Games and Visual Effects Research Lab, University of Hertfordshire

Scientists have used the tiny distortions imprinted on the cosmic microwave background by the gravity of matter throughout the universe, recorded by ESA's Planck satellite, to uncover the connection between the luminosity of quasars – the bright cores of active galaxies – and the mass of the much larger 'halos' of dark matter in which they sit. The result is an important confirmation for our understanding of how galaxies evolve across cosmic history.

Most in the universe are known to host , with masses of millions to billions of times the Sun's mass, at their cores. The majority of these cosmic monsters are 'dormant', with little or no activity going on near them, but about one percent are classified as 'active', accreting from their surroundings at very intense rates. This accretion process causes material in the black hole's vicinity to shine brightly across the electromagnetic spectrum, making these active galaxies, or , some of the brightest sources in the cosmos.

While it is still unclear what activates these black holes, switching on and off their phase of intense accretion, it is likely that quasars play an important role in regulating the evolution of galaxies across cosmic history. For this reason, it is crucial to understand the relationship between quasars, their host galaxies, and their environment on even larger scales.

In a recent study led by James Geach of the University of Hertfordshire, UK, scientists have combined data from ESA's Planck mission with the largest survey of quasars available to date to shed light on this fascinating topic.

According to the leading scenario of structure formation in the universe, galaxies take shape out of in the densest knots of the cosmic web – a filamentary network, made up primarily of the invisible , that pervades the cosmos. In turn, the complex distribution of both ordinary and dark matter originates from tiny fluctuations in the primordial universe, which leave an imprint in the cosmic microwave background (CMB), the most ancient light in the history of the universe.

The Planck satellite has been scanning the sky between 2009 and 2013 to create the most precise all-sky map of the CMB, enabling scientists to refine our knowledge of the age, expansion, history, and contents of the universe to unprecedented levels of accuracy.

Planck reveals link between active galaxies and their dark matter environment
Gravitational lensing of the cosmic microwave background. Credit: ESA and the Planck Collaboration

And there is more: as predicted by Albert Einstein's general theory of relativity, massive objects bend the fabric of spacetime around them, distorting the path of everything – even light – that passes nearby. This phenomenon, known as , affects also Planck's measurements of the CMB, which carry an imprint of the large-scale distribution of matter that the most ancient cosmic light encountered along its way to the satellite.

"We know that galaxies form and evolve within an invisible 'scaffolding' of dark matter that we cannot directly observe, but we can exploit the gravitational lensing distortions imprinted on the cosmic microwave background to learn about the dark matter structures around galaxies," says James Geach.

Gravitational lensing distortions of the CMB are small, rearranging the CMB sky picture on scales of about 10 minutes of arc – equivalent to just one third the diameter of the full Moon. But many tiny deflections from across the sky can be combined, with the help of statistical methods, to obtain a stronger signal, piling up the data gathered around many quasars.

In their research, Geach and colleagues analysed the latest gravitational lensing map obtained by the Planck team, made public as part of the Planck Legacy Release in 2018, in combination with 200 000 quasars drawn from the largest sample ever compiled, the more than half-a-million quasars that comprise Data Release 14 of the Sloan Digital Sky Survey quasar catalogue.

"By combining the Planck data with such a large sample of quasars, we could measure the mass of the dark matter halos in which the quasar host galaxies are embedded, and investigate how this varies for quasars of different luminosity," says Geach.

The analysis hints that that the more luminous a quasar is, the more massive its halo of dark matter.

Planck reveals link between active galaxies and their dark matter environment
Gravitational deflection by quasar-hosting dark matter halos. Credit: David Tree, Professor Peter Richardson, Games and Visual Effects Research Lab, University of Hertfordshire

"This is compelling evidence that a correlation exists between the luminosity of a quasar, energy that is released in the immediate vicinity of a supermassive black hole – a region spanning perhaps a few light days – and the mass of the encompassing halo of dark matter and surrounding environment, which extends for tens of millions of light years around the quasar," Geach explains.

"We're using the cosmic microwave background as a kind of '' to the universe. That backlight has been gravitationally lensed by foreground matter, and so by correlating galaxies with the Planck lensing map, we have a new way to study galaxies and their evolution."

The finding supports theoretical models of quasar formation, which predict a correlation between quasar luminosity and halo mass, in particular for the most luminous quasars, where the black holes are accreting matter at close to the maximum rate.

The study focused on distant quasars that are observed as they were when the universe was about four billion years old – about one third of its current age of nearly 14 billion years. This is close to the peak era of supermassive black hole growth. In combination with deeper quasar surveys in the future, the Planck data could enable scientists to push these investigations to even earlier times in cosmic history, up to the epoch when the first quasars formed.

"This result shows the power of Planck's gravitational lensing measurements, which make it possible for us to measure the invisible structures of dark matter in which galaxies form and evolve," says Jan Tauber, Planck project scientist at ESA.

"The legacy of Planck is quite astonishing, with data that are being used for a much wider range of scientific applications than originally conceived for."

"The halo mass of optically-luminous quasars at z~1–2 measured via gravitational deflection of the " by J. E. Geach et al. is published in The Astrophysical Journal, Volume 874, Number 1.


Explore further

Active galaxies point to new physics of cosmic expansion

More information: J. E. Geach et al. The Halo Mass of Optically Luminous Quasars at z ≈ 1–2 Measured via Gravitational Deflection of the Cosmic Microwave Background, The Astrophysical Journal (2019). DOI: 10.3847/1538-4357/ab0894
Journal information: Astrophysical Journal

Citation: Planck reveals link between active galaxies and their dark matter environment (2019, April 18) retrieved 26 May 2019 from https://phys.org/news/2019-04-planck-reveals-link-galaxies-dark.html
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Apr 18, 2019
Dark matter is a supersolid that fills 'empty' space, strongly interacts with ordinary matter and is displaced by ordinary matter. What is referred to geometrically as curved spacetime physically exists in nature as the state of displacement of the supersolid dark matter. The state of displacement of the supersolid dark matter is gravity.

The supersolid dark matter displaced by a galaxy pushes back, causing the stars in the outer arms of the galaxy to orbit the galactic center at the rate in which they do.

Displaced supersolid dark matter is curved spacetime.

In the Bullet Cluster collision the dark matter has not separated from the ordinary matter. The collision is analogous to two boats that collide, the boats slow down and their bow waves continue to propagate. The water has not separated from the boats, the bow waves have. In the Bullet Cluster collision the galaxy's associated dark matter displacement waves have separated from the colliding galaxies, causing the light to lense

Apr 18, 2019
Hey Bob, still trying to sell Universal Jell-O? What flavors does that come in, again? & can I get it sugar-free?

Apr 18, 2019
I would think this indicates dark matter is made from Black holes munching on ordinary matter.

Apr 18, 2019
The analysis hints that that the more luminous a quasar is, the more massive its halo of dark matter.


Bingo! Take this to the logical conclusion instead. The more massive the core star, the quasar, the more time it has ejected newly formed matter therein to build out the galaxy into a more massive monster, thereby influencing the surrounding halo of 'non-empty' space to refract light as dark matter. Never mind the galactic rotation problem, as it will likely be solved to be closer to MOND by considering that gravity does not have infinite reach.

Apr 18, 2019
Nice use of Planck data! And that more matter - of any kind - would be correlated with more massive supermassive black holes [SMBHs] and more galaxy core activity is unsurprising, but good to know.

"about one percent are classified as 'active'".

I did not know this! What I know is that in our galactic neighborhood about half the galaxies have "cusp", central peak "cold, classical" dark matter distributions, tentatively associated with low star formation rates; Milky Way is one of those (according to Gaia). And the other half has "core", evened out "hot" distributions, tentatively associated with active star formation associated with stuff like lots of mergers and active cores.

So - on the background of mergers and what not - if active cores are so rare, their SMBHs should go "on and off" at high rates as gas clouds drives their jets. Guess they could, they are small compared to the size of the galaxy they sit in.

Apr 18, 2019
I think my earlier comment may give the impression that I talk of AGN activity of the scales of days or weeks; as the just imaged M87* has. But the jet associated activity must live on scales of millions up to 100s of million years; see the length of M87 jet.

I would think this indicates dark matter is made from Black holes munching on ordinary matter.


Why would you think that!? The article or the suggested physics says nothing of the kind. (Besides that black holes as dark matter was soundly rejected the other week, The only such option remaining was "primordial" black holes from the Hot Big Bang, and they did not lens light at sufficient rates: https://phys.org/...ial.html .)

Apr 18, 2019
Why would you think that!? The article or the suggested physics says nothing of the kind.


Oh, sorry, I believe I see now, you mean that SMBH activity forms and release dark matter rather than constitute dark matter; sloppy reading on my part.

Well, in principle perhaps they could, super accelerator energy levels in those jets. But that would not explain the seen observations of lots of dark matter not associated with black holes. The article (and I) discuss how the distributions of already present dark matter around galaxies are affected by the latter, i.e. look to the differences rather than absolute numbers.

Apr 18, 2019
Well this all seems rather simple. Wait, that was the article on keeping cats inside. :o)

Will have to brush up on Quasars and Seyfert galaxies to get a feel for this stuff.

Regarding primordial black holes being eliminated as dark matter, and the data from micro-lensing of stars:

"Limits are model-dependent. It has been also argued that if primordial black holes are regrouped in dense halos, the micro-lensing constraints are then naturally evaded.[20]"

https://en.wikipe...ack_hole

Any takers on this one? I am going to guess maybe. (Please don't shoot the messenger.)

I still love this notion. The "simplicity" of PBHs makes the whole story so neat. That may be where the problem lies. Sadly, Occam's razor may not function here, or many others places in modern science, etc.

Apr 18, 2019
Recently two papers have been published. The first one deals with the measurement of the speed of rotation of galaxies and, in our view, closes the issue of the existence of dark matter. The second one argues that the expansion of the universe is not accelerating. However, this fact does not answer the question as to what in general is the cause of the universe's expansion and does not address the widespread opinion that 70% of the universe consists of dark energy.
https://www.acade...k_Energy

Apr 18, 2019
I agree that this a very complicated subject.

In my opinion we need to keep in mind that the activities increasing Galactic Core Masses? Are chance events.

Especially keep in mind, we are considering time-spans of billions of years.

The cores are always pulling in material that is in close enough proximity to the major gravitational attractants. Materials such as stars, gas clouds & even other galaxies.
Maybe Dark Matter?

When there is little infall?
We will observe the Cores to be generally quiescent.

I am hedging my bets here, since so much potential activity & inactivity are dependent on unpredictably random events.

We are trying to make sense of the trials of unpredictable Chaos.

Apr 19, 2019
"Limits are model-dependent. It has been also argued that if primordial black holes are regrouped in dense halos, the micro-lensing constraints are then naturally evaded.[20]"

https://en.wikipe...ack_hole


You can almost always wiggle out, but the models gets complex, so less likely. I am happy with the "first order" test rejection, but that is my personal opinion.

Apr 19, 2019
I suppose it makes sense to suppose that dark matter can compose some of the material that would form a black hole. But we don't know much about dark matter. It would be interesting to find that it would behave sufficiently unlike visible matter as to complicate the singularity issue. Forget about singularity in fact-- just consider an extremely dense and tiny mass in the blackhole's interior. What happens to this picture if dark matter is a significant component, and dark matter behaves very much unlike visible matter under such conditions? Of course, it's all academic since we couldn't observe any of this. But maybe interesting to think about.

Apr 23, 2019
If the red shift data is indicative of some other property of light over space or time, and not necessarily indicative of expansion, as Hubble originally suspected, then. . . all this can be explained by a much older Universe with more (non-luminous) baryonic matter hanging around.

In other words, revisit red shift, or drive on with the Universe being 99% dark energy and dark matter? I'll take door number 1.

nok
Apr 25, 2019
Universe? I think we have sufficient theoretical knowledge in place to demand tightening the language concept 'universe' which no longer references essentially one agreeable and reliable abstraction. Moreover, it oscillates between object and environment. In an observable expansion context, the referent itself does change dynamically. Possible examples being pov? observable? and extent? as relevant.

Apr 25, 2019
"...massive objects bend the fabric of spacetime around them, distorting the path of everything – even light – that passes nearby."

The parrot chirps again. File as fiction.

Apr 25, 2019
Light curving in the presence of gravity was confirmed by Sir Arthur Eddington in 1919.

https://royalsoci...920.0009

Published in 1920.

Apr 25, 2019
"I hold that space cannot be curved, for the simple reason that it can have no properties. It might as well be said that God has properties. He has not, but only attributes and these are of our own making. Of properties we can only speak when dealing with matter filling the space. To say that in the presence of large bodies space becomes curved is equivalent to stating that something can act upon nothing. I, for one, refuse to subscribe to such a view." -Nikola Tesla

Apr 25, 2019
I'm going with Einstein and Eddington. Tesla had a lot of wild ideas, among them denying Newtonian gravity. Never mind relativity.

Apr 25, 2019
I'll go with what I think. Tesla's understanding pretty much brought us the modern world.

Apr 25, 2019
Actually Tesla got pwnt by George Westinghouse.

On Earth.

But go ahead and believe whatever stupidity you see fit.

Apr 25, 2019
"...massive objects bend the fabric of spacetime around them, distorting the path of everything – even light – that passes nearby."

The parrot chirps again. File as fiction.


Observed fact.

Apr 25, 2019
"...massive objects bend the fabric of spacetime around them, distorting the path of everything – even light – that passes nearby."

The parrot chirps again. File as fiction.


Observed fact.


Abductive reasoning.

Apr 25, 2019
Observed fact. With pictures to prove it.

Fact a hundred years old, often verified by further observation.

Don't lie. It won't help. There is nowhere to hide.

Apr 25, 2019
"...massive objects bend the fabric of spacetime around them, distorting the path of everything – even light – that passes nearby."

The parrot chirps again. File as fiction.


Observed fact.


Abductive reasoning.


Sheer denial of observed facts = some sort of quasi-religious hero worship. Sad.

Apr 25, 2019
The ApJ paper is paywalled, but it is available on Arxiv, here;

THE HALO MASS OF OPTICALLY-LUMINOUS QUASARS AT Z≈1–2 MEASURED VIA GRAVITATIONAL DEFLECTION OF THE COSMIC MICROWAVE BACKGROUND
Geach, J. E. et al.
https://arxiv.org...6955.pdf

Apr 25, 2019
"...massive objects bend the fabric of spacetime around them, distorting the path of everything – even light – that passes nearby."

The parrot chirps again. File as fiction.


Observed fact.


Abductive reasoning.


Sheer denial of observed facts = some sort of quasi-religious hero worship. Sad.


Space isn't curved because....Duh! It's space. It takes blind faith to believe the obvious fairy tale of curved space. Honestly sit and think about it for a while.

Apr 25, 2019
It feel like I'm trying to convince a Christian congregation that people can't walk on water.

Apr 25, 2019
It feel like I'm trying to convince a Christian congregation that people can't walk on water.


Nope, you are talking complete crap, and said crap is shown to be wrong. Nobody cares about your science-free belief system. Go write it up.

Apr 25, 2019
Why do you think curved space is responsible for the path of light being affected by an object?

Apr 25, 2019
Why do you think curved space is responsible for the path of light being affected by an object?


It isn't what I think. It is what is predicted by relativity, and is observed. Nobody is claiming otherwise. If you believe differently, then link to the paper that contends that lensing is due to something else.

Apr 25, 2019
I don't need a paper to know that lensing is due to something non-fictional.

Apr 25, 2019
Looks like Benni has a new sock puppet

Apr 25, 2019
Looks like Benni has a new sock puppet


Yup. All talk, no science!

Apr 25, 2019
"Curved space" is non-sense.

nok
May 04, 2019
"...To say that in the presence of large bodies space becomes curved is equivalent to stating that something can act upon nothing..." -Nikola Tesla


Nothing. Opposed to my above observation 'nothing' is quite well-defined. In fact, it's perfectly defined. It has no referent. When we speak of anything as nothing, make no mistake, we make the same claim each time. Now, say, in discussing physics, to reference nothing is to claim the referrer itself, in your case, space, is nothing. Forthwith, every time you utter the word 'space' you will have eructed an extraordinarily large contradiction, which, even if followed by eternal silence will unlikely ever redeem you from such an egregious display of bad form. Cheer up, if you're right we'll all be together like a tin of sardines, no longer separated by length, height or width, sailing forth in the kind of agreeable absolute simultaneity one really can't refuse.

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