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Supermassive Diet: Black Holes Bulk-Up On Dark Matter
astroengine writes It has long been assumed that the size of a supermassive black hole in a galaxy's core is intimately related to the number of stars that galaxy contains — but it might not be that simple after all. According to new research, it may in fact be a galaxy's extensive dark matter halo that controls the evolution of the central supermassive black hole and not the total number of stars that galaxy contains. "There seems to be a mysterious link between the amount of dark matter a galaxy holds and the size of its central black hole, even though the two operate on vastly different scales," said lead author Akos Bogdan of the Harvard-Smithsonian Center for Astrophysics (CfA), Cambridge, Mass.
After switching my diet, my blackhole no longer bulks up my dark matter.
Dark matter only interacts gravitationally with baryonic matter, right? If so, then I'd think it's pretty obvious that dark matter would be a major constituent of a galaxy's supermassive black hole. But then, according to Sheldon Cooper, I have only a Masters' Degree - in engineering, at that - so what do I know?
"A little misunderstanding? Galileo and the Pope had a little misunderstanding."
"Assuming?" I presume you know nothing of the abundance of research on the subject and you're talking out of your ass? Google "galaxy rotation curve" and "bullet cluster" before you embarass yourself further, please. Can't believe this trash gets modded as insightful...
Actually, it's an acronym but anyway...
MoND
I tried a supermassive diet, but it didn't work out so well. Turns out metabolism doesn't work that way.
Take it to the limit, everybody to the limit, come on, everybody fhqwhgads.
We also "assume" normal matter exists using the same definition of "assume'". It is true that Dark Matter could be a collection of stuff and not a single thing, but we know for sure that it is not normal.
Could it be that when energy/matter is ingested by a black hole it gets squeezed beyond the plank scale and into a dimension that is different than the space-time dimension we perceive; a dimension unconstrained by the black hole's gravity well -- effectively allowing the consumed energy/matter to exhaust back out into the galaxy as a different form?
Where's my latte dude? get back to work.
Know is a tricky word, but there is plenty of evidence that most of the dark matter is not baryonic. The proportions of light elements formed at the end of the big bang gives a contstaint on the baryon density of the universe at the time, as do the ripples in the cosmic microwave background (which reveal the balance between radiation pressure and gravity in the early universe and tell us that most of the mass did not interact with photons at all). The bullet cluster is another piece of evidence. The stars in the colliding galaxies interacted with one another and with dust and merged into one bigger galaxy, but something, detectable by its gravitational lensing of galaxies beyond it, went straight through. It's hard to see how brown dwarves would have done that.
They've already accounted for all forms of known types matter, including brown/black dwarfs.
Nice. Dark matter is the result of matter falling into the singularity.
Ok, ignorant i will answer on your level: Sure, just after i will take my dick from your mouth.
So where are all the dark matter black holes?
Sorry, I didn't realize that English wasn't your first language. I take back my previous post. No bully okay?
None of what you just wrote makes any sense... You're using word that a scientists might use, but out of their proper context. Again, google "galaxy rotation curve" and "bullet cluster". From what I gather, you seem to think we think dark matter exists because we're missing mass, but you are not taking into account the locations where we are missing mass. Black holes can't be responsible for what we're seeing. Also, dimensions are not places. Something can't be "in" a dimension. That's like saying that you got lost in a the third dimension... length! Dimensions are used to describe points in spacetime. The extra dimensions of string theory (which has yet to be proven in any way, might I add) can be thought of as extra numbers that you assign to every point of spacetime. That's all.
And just what a is a gravitational shadow?
Also the gravity that we see from black holes is from the core of the dead star that gave birth to them... Or in the case of supermassive black holes, the gas that presumably collapsed to form it. It is real matter, not twlight zone matter, and its effect is fully accounted for and routinely simulated.
Bullet cluster. Google. Now.
Why is it that people who have spent 30 seconds thinking about the problem think they know better than significantly more intelligent people who have spent decades? Especially when the (very large and convincing) amount of evidence for dark matter is easily accessible through a bit of googling. Guys, dark matter isn't just scientists throwing their arms in the air. It just works. Models with dark matter work much better than models without. And we've made multiple observations of things that point to dark matter existing. And no, it can't be black holes or brown dwarfs. That's been thought of a long time ago and it doesn't work. If you have a better idea and years of papers to support it, by all means, you can trash talk dark matter. Otherwise, please don't spread your ignorance. Science is not a democracy, and your opinion doesn't matter if it's unsupported.
Or this research should point us in the other direction. Perhaps it's the size of these black holes that is the source of the extra gravity that we currently attribute to the existence of dark matter...
I've always figured there is a term missing from our formula for gravity that is only significant at large scales. Perhaps with larger black holes, this theoretical missing term is similarly larger.
09F91102 no, 455FE104 nope, F190A1E8 uh-uh, 7A5F8A09 that's not it, C87294CE no. Ah! 452F6E403CDF10714E41DFAA257D313F.
Remember we learned today that dark matter is information and when a tree falls in the forest it DOES make a sound.
411 Y0UR 8453 4R3 8310NG 70 U5!! -NSA
Stars on the outskirts of a galactic disk have been observed to orbit in around the same time as the inner ones. This means there is more mass in the galaxy that we can see. Something like an order of magnitude more. Feel free to dismiss it as an assumption if you like, but I don't see your alternative explanation. Your casually ignorant arrogance is sadly really typical of this place.
I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
The rotation rates of stars in the outer edge of a galactic disk is inconsistent with your theory that all the missing matter is in the black hole. The distribution is likely to be spherical and possibly larger than the galaxy in extent.
I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
So now we're assuming dark matter exists and we know how much of it is in any given galaxy?
I'm far from an expert in the subject but as I understand it's pretty simple. Total Mass (or whatever) or a galaxy - visible/known mass = assumed dark matter mass.
If we weren't assuming it wouldn't be dark.
Wanna buy a shirt?
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You're not hearing me. The "location" of that mass is obviously not in the center of the singularity, given the rotation rates. Of course there is no such thing as a center of a singularity, it has no volume at all, so I'm not sure why people would expect gravity, which depends on mass in a 4d manifold, to emanate from it.
(But dang, flamebait, really? It's a science discussion; it can't be flamebait. What are we supposed to talk about here then? We want hundreds of posts that all simply repeat the current theory?)
In the bullet cluster the stars passed right through each other as well it is only the dust clouds in the galaxies that really exchanged momentum. So extra brown dwarfs as dark matter probably isn't in conflict with the bullet cluster.
As you point out BBN and CMB measurements do suggest that dark matter in non-baryonic. Another one to add to that list is structure formation, the large structures of the universe would be very different if the dark matter was baryonic.
If we don't know how many brown dwarfs there are we don't know how much non Baryonic matter there is. Duh.
Baryonic matter has _not_ been excluded. It's unlikely to account for all of the missing matter, but certainly accounts for some.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
All points in space have volume. The smallest anything can be is a cubic plank unit, which still has volume.
OK. I stand corrected.
The distinction here is the complete lack of humility showcased by people like you. You know that you know very little about the subject, and yet you start to make claims about how things work as if you had any authority. When you don't know much about something, you approach it with humility and try to better your reasoning before passing judgement. For example, I gave you some excellent starting points for your journey. How much time did you spend writing that post? Now, did you actually google "galaxy rotation curve" and "bullet cluster"? Cause if you didn't, I think it just shows everyone how you have zero desire to learn and only want to be argumentative for the sake of it. You lack humility. If you had approached me and asked me kindly to explain to you why dark matter must exist, I would have gladly explained this to you. But if you act like a jackass and pass judgment on something in complete ignorance of the facts, you're going to get a keyword and an invitation to google it. Dipshit.
If you can't see the difference between "Hey, I don't understand why this must be true. It makes no sense to me. Can you explain?" and "Haha! Scientists are such morons for thinking this!", you've got serious issues, and it's not my job to fix them.
The only loudmouths are the people who are claiming to know better than scientists despite being completely ignorant of the facts. As I explained above, there's a difference between "I don't understand, can you explain?" and "I don't understand, this is stupid." The first will get you a helpful reply. The second will get you scorn, a keyword and an invitation to goole.
Also, I don't think you spent very long thinking about the bullet cluster. It is solid evidence for dark matter. Alternative explanations cannot explain this behaviour to the same precision, something that even a cursory search reveals. You can't just look for one discerning opinion and use that to justify your position, that's cherry picking data. The preponderance of evidence is in the direction of the existence of dark matter. I gave you a place to start, now go and educate yourself. This is slashdot, people here are supposed to be good at learning on their own.
I'm not going to get into an argument about how many dimensions (in addition to the standard 3+1) the Universe has (do note that the inverse square law implies three spatial dimensions). However, saying something is "in" a dimension is stupid. You can say that most of the Universe is at one fifth-dimensional coordinate value and something else is at -20m from that (in a certain frame of reference), but that's not really saying it is in the fifth dimension, and I have no idea how you'd falsify it. If whatever strange ideas you cook up aren't potentially falsifiable, you're not talking science.
Singularities have no volume, true, but their effects do. Singularities containing enough mass to matter have event horizons big enough to matter, and you can't falsify any theory about the details of what happens inside an event horizon. (You can make calculations based on certain assumptions, and people have, but that isn't is more using the results of science than actual science.) Now, suppose you have a singularity (which you cannot see) that has mass, and you put more mass in. It goes into the singularity, duh. If you can put mass into something, there's no conceptual reason why you can't put more mass into it. You've now got a bigger black hole.
You also haven't explained galactic rotation curves, which imply distributed unseen matter, not centralized unseen matter.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
Last I looked, while that was a plausible theory, there was no real evidence for the Planck length being significant. It's a very plausible hypothesis, but at the moment that's all is.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
Dark matter is matter that does not interact using electromagnetism. Simple enough? Think something like slow, massive, neutrinos. (Three sentences.)
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
First, thank you for phrasing your comment in a respectful way. It goes a long way to getting some good answers. I actually want to help you.
It is probably not supermassive black holes that are responsible for dark matter. That is in fact why I encouraged others to google for "galaxy rotation curves". Your orbital speed around the center of the galaxy is affected by the amount of mass inside that orbit and your distance from the point you're orbiting. Since most of the mass in the galaxy is close to the center, we should expect that a plot orbital speed vs distance would result in the orbital speed decreasing after a certain point, since there is little mass being added inside the orbit with distance. However, that is not the case. What we observe is that the orbital speed just keeps going up and up as you go further out. This relation is not just true for our galaxy. We have catalogues full of rotation curves for galaxies that obey this relation. This seems to indicate there is extra, non-luminous mass out there, further out from the center.
This means the supermassive black hole cannot be responsible for this, as its mass is located entirely in the center. The extra mass must be futher out for this to work. We quickly thought it might be objects like brown dwarfs (failed stars, essentially) that caused this, but our experiments overwhelmingly demonstrate this is not the case. That is why the commonly accepted theory is that dark matter must be particles.
Let me add that galaxy rotation curves are but one piece of a large body of evidence in favour of dark matter. The existence of dark matter is hardly a matter of debate amongst astronomers and astrophysicists. Sure, you've got some theory people trying to come up with alternate explanations cause that's their job, but by and large dark matter must exist for things to make sense. We have seen the shadow of the beast, we know it is there. Now we just have to find it.
This seems to indicate there is extra, non-luminous mass out there
And that's the statement that I question. Sure there's an extra force, but is it due to more mass or just more gravity than we expect? Can a super-massive black hole contribute more gravitational force at greater distances than other forms of matter?
I don't have the data at my fingertips, and I suspect I'd get the maths wrong. But is this new finding inconsistent with my above poorly defined idea?
09F91102 no, 455FE104 nope, F190A1E8 uh-uh, 7A5F8A09 that's not it, C87294CE no. Ah! 452F6E403CDF10714E41DFAA257D313F.
As far as we know, gravity acts the same way for black holes as it does for everything else. There is no reason to believe that it could be different for supermassive black holes.
And this is the part that requires a bit of trust. People have tried alternate theories of gravity, but they always kind of single out one case and manage to do an ok job, but no one has come up with anything that explains such a large amount of observations as dark matter. Dark matter just works for a wide range of situations. This is why people are so confident in its existence. To prove this, you need to do some math, unfortunately. I can't explain the ideas to you, but ultimately what distinguishes between something that's just a neat idea and what is actually real is the cold hard math. We might dislike the idea of dark matter, but bear in mind that people really disliked quantum mechanics when it was first introduced. Our dislike for something doesn't affect how real it is. It's the experiment that makes the call.
There are many papers on the subject if you want to investigate, but it makes for quite dense reading.
Thank you for the correction. Dark matter is matter that does not interact electromagnetically, or does so only very weakly. Got it. Is there any reason to think it would or would not be affected by the weak force?
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes