Red stars and big bulges: How black holes shape galaxies

Red stars and big bulges: how black holes shape galaxies
Images of a small fraction of the galaxies analysed in the new study. The galaxies are ordered by total mass of stars (rising from bottom to top) and by ‘bulge to total stellar mass ratio’ (rising from left to right). Galaxies that appear redder have high values for both of these measurements, meaning that the mass of the bulge –and central black hole – determines their colour. Credit: A. Bluck.

( —The universe we can see is made up of billions of galaxies, each containing anywhere from hundreds of thousands to hundreds of billions of stars. Large numbers of galaxies are elliptical in shape, red and mostly made up of old stars. Another (more familiar) type is the spiral, where arms wind out in a blue thin disk from a central red bulge. On average stars in spiral galaxies tend to be much younger than those in ellipticals.

Now a group of astronomers led by Asa Bluck of the University of Victoria in Canada have found a (relatively) simple relationship between the colour of a galaxy and the size of its bulge – the more massive the bulge the redder the galaxy. The researchers publish their results in the Oxford University Press journal Monthly Notices of the Royal Astronomical Society.

Asa and his team used data from the Sloan Digital Sky Survey to group together over half a million galaxies of all different colours, shapes, and masses. They then used pattern recognition software to measure the shape of each one, to see how the proportion of red in a galaxy varies with its other properties.

They found that the in the central bulge (regardless of how big the disk surrounding it may be) is the key to knowing the colour of the whole galaxy. Above a given bulge mass, galaxies are red and have no new young stars.

Almost all galaxies have at their centres. The mass of the bulge is closely related to the mass of the black hole; the more massive the black hole the more energy is released into the surrounding galaxy in the form of powerful jets and X-ray emission. This can blow away and heat up gas, stopping new stars from forming.

Asa comments: "A relatively simple result, that large galaxy bulges mean red , has profound consequences. Big bulges mean big black holes and these can put an end to star formation."

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Ellipticals and spirals comprise two different populations of "green" galaxies

Citation: Red stars and big bulges: How black holes shape galaxies (2014, April 22) retrieved 22 September 2019 from
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Apr 22, 2014
"So... you think, for no good reason whatsoever, that the material was pulled up by... some other thing that you must invent entirely to explain why the material was pulled up.... That's not how science works, sorry."

Nope. You cannot state there is no good reason just because you ignore it. The observations of mass and luminosity alone put established objects out of the picture. Nothing known can be that massive and that dense, therefor something else is needed.

Black holes were theorised long before there were any observations to suggest them, they were not invented. SMBHs were a hypothesis to explain AGN in general. It was tested far beyond simple x-ray measurements inducing direct observations of orbiting stars, velocity profiles and orbiting masers. That's science, testing a hypothesis. That's all science is.

Apr 22, 2014
it is the least likely stucture to exist in the universe...except on paper. DM "particles" are a close second
@no fate
I think you might be having a problem with DM because you dont understand what DM is... it is really simple.
DM = Dark Matter = simply a name placeholder for an observed phenomenon that we are not able to currently describe in detail. We DO know certain things: it has mass (observed & inferred) which is where the "matter" part of the name comes from. it does not interact with light like normal matter which is where the "dark" comes from. thus, Dark matter is simply matter that is undetectable by its emitted radiation, but whose presence can be inferred from gravitational effects.

good video here: http://www.pbs.or...ter.html

Apr 22, 2014
showed this doesn't work as per points 1 & 2.

False. The model tells us the mass is there, you have nothing to show otherwise. That's just prejudice. We have a model which quantitatively explains these motions. We can test it, that's science.

They have attributed observations to an effect

That's all science is. You build a model and test it. They thought it was a black hole so they looked for orbiting objects, test and evidence. If you claim this does not apply to objects that have never been observed then nothing new could ever be observed.

A black hole isn't the only answer for these emissions

That's true of any scientific model. It explains more observations quantitatively than other models.

given what materials sciences tell us...

No, that's a shallow dismissal. If you want to talk about theory be specific, pointing to a vast field of physics and claiming "the evidence is in there" is not an argument.

Apr 22, 2014
it shouldn't be as difficult to find as it is proving to be.

Says who? The fact it's abundant doesn't mean it is easy to detect.

Nature tells us otherwise.

No it doesn't. What natural phenomenon tells us dark matter doesn't exist? None, that's pure bias. It's a model, we can test it. That's science right there.

The "now we have it right" rhetoric doesn't fly.

That's not scientific criticism. If models were thrown away at the first sight of conflicting data we would have nothing. Conservation of energy and momentum, abandoned. Classical electromagnetism, abandoned. No, that's not how science works. We know our models work well so far so how can we extend their usefulness and how can we test that extension?

gravitationally compress to a star under it's own mass...not physically possible

I asked you to be specific. Why isn't it physically possible?

Apr 22, 2014
Interacting magnetic fields behave exactly how DM is proposed to....and...they exist
@no fate
this is where you and I will differ.
interacting magnetic fields (IMF) do not have mass, nor do they allow for the observed lensing or (again observed) galactic stellar motion. There is no data to support IMF as a reliable substitute for the placeholder name of "dark matter".
according to what I have read thus far, dark matter is the only thing that covers it all with one simple object (albeit unknown and invisible currently to us).
Sure, we have inferred it, but the inference is due to observed phenomenon (as I stated above)

IMHO - I believe that this was addressed earlier on when the observations were first noticed, but there is no supporting empirical data that would show/allow for IMF to replace DM.

If you have anything to support your position, feel free to post it.

I would suggest sticking to reputable science sites and not anything like EU spam though.

Apr 23, 2014
@ no-fate-Skippy, it looks like you mixing up what the Reg-Skippy and the cantdrive-Skippy are all the time writing about. Don't listen to them Cher they is both the wrong when it comes to the science stuff. Reg-Skippy is the one that says there is no gravity, but that is wrong Cher, you can google that. cantdrive-Skippy is the one that writes all the foolishment about the plasmas and magnets. You got them crossed up. Not one or the other of them knows about real science stuff so quit trying to use their stuffs to help you understand this stuff. Stick with the smart peoples like Captain-Skippy and Magnus-Skippy and the IMP-Skippy, they are the Skippys that know this stuff.

Apr 23, 2014
The same one telling you it You just disagree with ones that don't say what you want to hear.

Where did I say the dynamics of the universe told us dark matter exists? I didn't, it doesn't. What the voices in your head are telling you is irreverent. It's a model, we can test it. Anything else isn't science.

Find one experiment where gravity does and post your evidence please.

Gravitational lensing round the Sun. From only the value of GM taken from observations general relativity predicted gravitational lensing as well as can be measured. What other model can claim that?

the physical properties of Hydrogen will not allow it to self compress due to it's own mass, regardless of ANY math that says it can.

Ok, so you can observe a few hundred littres of hydrogen, how do you predict what the "physical properties of hydrogen" will do in the presence of a solar mass of the stuff? Only math can tell you that. Ignoring mathematics is willful ignorance.

Apr 23, 2014
Has any mainstream physicist in the history of the world been able to condense hydrogen outside of a storage device?

Has any crank scientists in the history of the world been able to accumulate a Jean's mass of hydrogen? No. I can heat an egg up to a few hundred degrees but I see no plasma. Does that mean plasma cannot exist because I did not observe it? No. The same goes for this stupid experiment of yours. Saying something hasn't been done doesn't mean it is impossible. Was manned heaver than air flight impossible before the 20th century? Of course not.

In a vacuum chamber we can create structures that look somewhat similar to what we see in space using plasma and magnets.

Just no. Even the most advanced plasma galaxy modes do not describe the most basic features. Scott's model (all math by the way) cannot explain the agreement between Hi regions and stars in rotation.

When you are out by this much, it is the fundamental principle that is flawed

Pure assumtion

Apr 23, 2014
here is one of many papers
@no fate
actually, this is just google results... but from one of those results found here http://van.physic...?id=2009
Nice try. Unfortunately, the path light takes is not affected by the presence of a magnetic field
even though a magnetic field won't do anything for the light, a gravitational field, sufficiently strong, will in fact bend light. This was observed early in the 20th century confirming Einstein's General Theory of Relativity in which light from the planet Mercury was bent by a very tiny amount by the enormous gravitational field of the sun

also... about this comment
Google it and there are dozens of examples of EXPERIMENTAL evidence
just because there are Google results, doesn't mean that it is empirical experimental data, after all you can also find https://www.googl...ens+real
75 million results for that link

Apr 23, 2014
Find one experiment where gravity does and post your evidence please
@no fate
1 experiment where gravity bends light? REALLY?
start here:

then: http://en.wikiped...lativity where you will also find references to the Eddington study
Dyson, F. W.; Eddington, A. S., Davidson C. (1920). "A determination of the deflection of light by the Sun's gravitational field, from observations made at the total eclipse of 29 May 1919". Philosophical Transactions of the Royal Society 220A: 291–333.

I would recommend only using reputable science links when researching. otherwise you will get EU crap and get confused.

Apr 23, 2014
In a vacuum chamber we can create the structures we see in space using plasma and magnets
@no fate
you will also notice that studies in cosmology take this into consideration when researching or writing papers. here are some sites to help you:


your conjectures are reminiscent of EU speculations about modern cosmologists not knowing /considering plasma physics, which has been proven wrong time and again.
to IMF lensing
If your magnetic field is strong enough over a large enough distance, you can have enough energy stored in it to do gravitational lensing, and then refer to the above answer on gravitational lensing. This however is a very difficult way of getting a strong gravitational field. It is much easier just to collect a galaxy's worth of matter than to collect the equivalent energy in a magnetic field (neither is particularly easy, I admit!)


Apr 23, 2014
@no fate
more from that Google link http://van.physic...?id=2009
there is a small expected deviation from linearity of electric and magnetic fields due to quantum mechanics and the ability of electrons to pop out and go away on microscopic time scales. This only becomes noticeable for very very high frequency light colliding with other very very high-frequency light (it wouldn't be noticeable and may even have exactly zero effect for a static magnetic field and visible light -- I haven't done any calculations). There are plans to make such a light-light collider, but it requires a many-mile electron accelerator to get the energy of the light high enough

so far, you have proven nothing as far as empirical data supporting your IMF Lensing theory, and requested that I Google for info myself.
without getting into known EU crank sites, I am not finding info (but not looking hard either). I would suggest you get the empirical data and present it yourself.

Apr 23, 2014
@no fate
and again, refuting IMF's bending light
we have a beautifully accurate theory of electromagnetism, tested countless times here on earth. So we know that EM fields don't bend the paths of light, except to the negligible extent that their energy is itself a source of gravity, or that there's quantum-mechanical photon-photon scattering. Here on earth, you can shine two laser beams through each other or shine a beam through a big magnetic field, etc. to check that we're not missing something about electromagnetism. You may want to know how accurate our EM theory (quantum electrodynamics) actually is. In one case (the electron gyromagnetic ratio) it predicts a number to an accuracy of one part in one hundred billion

is there anything that you would care to add in support of your IMF lensing hypothesis?

so what we have I evidence against IMF lensing and nothing for it. you will have to provide some links for your support, otherwise we'll just spin in circles, ok?

Apr 23, 2014
What possible delusion makes you think that physical properties of Hydrogen at a given temperature change due to how much of it there is?

Can I liquidate gases with a compressor? Yes. So the physical properties of hydrogen depend on the pressure. So replace the compressor with a solar mass of hydrogen sitting on top. The physical properties of hydrogen at a given temperature depend on how much there is.

A Jeans mass is entirely relevant when we are discussing gravitational collapse.

Apr 23, 2014
Aren't you astounded by how much we don't know? Dark matter and dark energy are wonderful analogies for human ignorance and acting out of ignorance.

I think you might be having a problem with DM because you dont understand what DM is... it is really simple.
DM = Dark Matter = an observed phenomenon we are not able to describe in detail.... thus, Dark matter undetectable by emitted radiation, but can be inferred from gravitational effects.

The link above has a post boasting " DM detectable within 10 years." Good luck with that. You can be absolutely wrong but if enough people parrot your dogma, Nobel will give you a prize.

Our present position in the Universe on one of the spiral arms of the Milky way is not precisely known. We are between our SMBH and Andromeda's. The galactic current sheet is not known.
Could not the observed distortions including the acceleration of expansion be explained by two SMBH closing proximity?

Apr 30, 2014
Astrophysicist George F. R. Ellis explains: "People need to be aware that there is a range of models that could explain the observation.For instance, I can construct you a spherically symmetrical universe with Earth at its center, and you cannot disprove it based on observations.You can only exclude it on philosophical grounds. In my view there is absolutely nothing wrong in that. What I want to bring into the open is the fact that we are using philosophical criteria in choosing our models. A lot of cosmology tries to hide that."

I see the high priests of acceptable dogma are hard at work trying to discourage dissent. Going to get a lot harder to disparage EU theory with all the empirical evidence coming in.

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