I was watching a program that aired tonight on the science channel and it was discussing how black hole may play a central role in the formation and evolution of galaxies... I believe they said that all galaxies have a super-massive black hole that has a mass that's .25% of the galaxy's mass.

So what I'm searching for is any information about how black holes may have effected the formation and evolution of galaxies... any info on the subject would be appreciated

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The first principle is that you must not fool yourself - and you are the easiest person to fool.
~~~ Richard Feynman ~~~
It is imperative in science to doubt.
~~~ Richard Feynman ~~~
Common sense is not so common
~~~ Voltaire ~~~

0.25% is way too large. The mass of the central Black Hole for the Milky Way is about 4x10⁶ solar masses, but the whole Milky Way comes in at about 10¹² solar masses. 0.25% Of the whole mass is 2.5x10⁹, but 4x10⁶ is only about 0.0004% of the mass of the Milky Way.

it is now well established that the velocity dispersion of the stars in the central bulge of a spiral galaxy is directly proportional to the mass of the central black hole, which implies a connection between the formation of the black hole and the formation of the stars around it (i.e., Alister, 2008; Cen, 2006 published as Cen, 2007).

I don't think the black hole plays a central role in the formation of the galaxy. Rather, the formation of the galaxy is what allows the formation of the black hole. However, it does seem that the black hole plays a central role in the evolution of galaxies. Quasars are thought to be powered by mass accretion onto a central super massive black hole. Quasars are limited to a narrow range of redshifts, and there are no low redshift quasars. It is likely that quasars represent the stage in galaxy evolution where the central black hole is actively accreting mass.

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The point of philosophy is to start with something so simple as not to seem worth stating, and to end with something so paradoxical that no one will believe it. -- Bertrand Russell

Here Ya Go...I hope you TV'oed it You can definitely pick up more 'intuitions' watching it multiple times.

http://www.bbc.co.uk/science/horizon...anscript.shtml

Tim is right that .25% is wayyyyyy to large....it was the SMBH's mass is 1/2 of 1% of the "Whole Galaxies Mass". There is another number the Nuker Group came up with for the ratio of the mass of the SMBH to just the "Bulge Mass", but I don't recall offhand what that was right now....it wasn't in that show.

Tim is a little off about a couple of other things that I will respond to in his post.

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RussT
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Everything is, as it should be, otherwise, it wouldn't be!

While this is certainly the case, the Nuker Group went well beyond just the 'central bulge' in terms of the relation between the rotation rates of the entire galaxy, including the speeds of the stars in the outer rims, where those stars cannot feel the SMBH at all.

The Nuker Group saw this quite differently.

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RussT
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Everything is, as it should be, otherwise, it wouldn't be!

I'm not sure it's true to say there is an SMBH at the centre of every galaxy. Bulge dominated galaxies - yes, but not all galaxies.

While I don't know what the average mass of the SMBHs as a percentage of the total galaxy mass is, I don't think it's fair to compare that 0.25% value to the Milky Way since, from memory, it's SMBH is underweight compared to the 'norm'.

This Nature paper is a place to start -- it (and another one by Volker Springel, Tiziana Di Matteo and Lars Herquist) opened the floodgates on the theoretical modeling side. Laura Ferrarese's paper (this one is an update) along with the work of Tremaine and co-workers and Gebhardt and co-workers (and probably others who I don't remember right now) pioneered the observational side.

The established ratio is ~0.002 (0.2%) between the masses of the central supermassive black hole and the galaxy's stellar spheroid mass. And yes, it is viewed as a co-evolution between the supermassive black hole and the stellar spheroid. This paper describes this mechanism for an extreme case.

The MW's ratio falls a bit on the low side of the correlation, and there are studies that have been done and are underway to understand whether this ratio is a function of lookback time (redshift) or other parameters (such as environment). It is thought that this number (0.002) represents something like an asymptotic ratio between stellar spheroid mass and central black hole mass.

This paper from Science by John Kormendy of the NUKER team summarises their understanding of the correlation between Black Hole mass and the mass of the bulge, and sigma, the velocity dispersion.

It would appear that the formation of the stellar concentration, or bulge, and the black hole at the centre of the bulge, are both symptoms of the merger history of the galaxy, rather than one arising from the other.

There was also a suggestion recently that formation of a SMBH can jet gas out of the galaxy core thereby bringing growth to an end.

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plenty of woo, at the hotel hoagaland...

My bad... I was going on what the science channel show said, which was "1/2 of half of a percent"... I'm not sure why they were quoting such info if it's indeed false... is the NUKER group mainstream?

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The first principle is that you must not fool yourself - and you are the easiest person to fool.
~~~ Richard Feynman ~~~
It is imperative in science to doubt.
~~~ Richard Feynman ~~~
Common sense is not so common
~~~ Voltaire ~~~

John Kormendy certainly is. And if by the NUKER team you're talking about these guys, then certainly they are. And it's not the mass of the MW, but the mass of the (true) stellar spheroid (the bulge) that's relevant here.

OOPs, not so fast...;>)

http://www.sciencedaily.com/releases...0411070039.htm

It is certainly beginning to appear that if it rotates like a galaxy, even Dwarfs, that it has a Massive Black Hole.

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RussT
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Everything is, as it should be, otherwise, it wouldn't be!

That article doesn't contradict what I wrote. Perhaps you should take a closer look?

There is a strong possibility that the Birth of the SMBH is intimately tied to the creation of the galaxy.

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RussT
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Everything is, as it should be, otherwise, it wouldn't be!

Maybe the BH came first and was the nucleus about which the galaxy formed. It's excessive to claim that all galaxies have a central SMBH because there are various processes such as collisions between galaxies and mergers of binary SMBHs which could separate a galaxy from its SMBH, even assuming every galaxy is "born" with a SMBH.

This topic has come up several times before.

And, as usual, Spaceman Spiff is on the ball, while RussT is misinterpreting the press-releases he is quoting.

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"What do you care what other people think?" -- Richard Feynman
"For a successful technology, reality must take precedence over public relations, for nature cannot be fooled." -- Feynman, at the conclusion of his Challenger report

Sorry, But here's what you wrote;
I'm not sure it's true to say there is an SMBH at the centre of every galaxy. Bulge dominated galaxies - yes, but not all galaxies.

Now, if that does not give the distinct impression that only bulge galaxies contain SMBH's, then I don't know what to say!

Why don't you guys just admit this kind of stuff when it happens rather than nit-picking everything to death. Over the last 3 years I have tried presenting these kinds of things in every way imaginable...oops's, humor, giving praise and then showing the discrepancy, Etc Etc Etc...but it doesn't matter in the end!

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RussT
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Everything is, as it should be, otherwise, it wouldn't be!

This statement is absolutely correct. M33 is an example of a galaxy whose central black hole is no more than ~a few thousand solar masses. Greene and Ho have found evidence for quite a few others like this. That there exist bulgeless galaxies with SMBHs does not contradict the statement that some galaxies do not have central SMBHs.

What are you driving at, RussT?

__________________
"What do you care what other people think?" -- Richard Feynman
"For a successful technology, reality must take precedence over public relations, for nature cannot be fooled." -- Feynman, at the conclusion of his Challenger report

Rather than just make a derogatory statement about...RussT is misinterpreting , please, explain to the class, what and how I am misinterpreting.

ANd, if you would like, I will show where the scientists themselves have said certain things VS the 'science writter'!

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RussT
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Everything is, as it should be, otherwise, it wouldn't be!

Bulge dominated galaxies - yes, but not all galaxies.

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RussT
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Everything is, as it should be, otherwise, it wouldn't be!

As Parejkoj has pointed out, there are observations which show no evidence for a SMBH in galaxies such as M33 and NGC 205. These observations use stellar dynamics to constrain the existence of a black hole at the galaxy centres to have an upper mass limit of ~3000 - 30000 solar masses. Thus, while there may be black holes at the centres of these galaxies, they certainly aren't supermassive. (see e.g. here)

Thus, my statement is correct - it is not true that there are supermassive black holes at the centre of every galaxy. I am not saying that they only occur in bulge dominated galaxies, nor am I saying they don't occur in galaxies without a bulge, rather it is probably more correct to say they occur at the centres of all bulge dominated galaxies.

Hogg lauds the quantitative treatment given to disk collision models that produce the bulge-dominated galaxies.

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Everyone is entitled to his own opinion, but not his own facts.

It does not give that distinct impression. It gives the distinct impression that galaxies of types other than bulge dominated may contain an SMBH at their center, but not all galaxies of that particular type.

Your misinterpretation seems to be that the second sentence is equivalent with "Bulge dominated galaxies - yes, but no other types of galaxies." and I don't think it is.

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Geeezzz...
Uh, No, parejokj did not leave out the "S"

And Now, we are down to arguing "S" (Super MBH) and "I" (Intermediate MBH)

And then you link to Dwarf galaxies M33/NGC 205 with, galaxy centres to have an upper mass limit of ~3000 - 30000 solar masses.

And I link above to LSB's with, The scientists determined that galaxy NGC 4395, a flat "pure-disk" galaxy with no central bulge, has a central black hole approximately 10,000 to 100,000 times the mass of our sun.

Then you make your supposedly "More Correct" statement...
SO, let's see, for the kids/novices/inquiring minds want to know people reading Q&A, to become better informed and hopefully 'less confused' about Astronomy, it would appear, that by just using your bulge dominated galaxies for SMBH's has left a great deal of confusion, because again, it would appear that my orginal statement...
Where I left off the "S", is the MOST correct statement after all.

Now we could argue till the cows come home, when they actually died at the top of the snow covered mountain, as to whether "Every Galaxy" can ever be 'verified' to contain a SMBH/IMBH.

It has become pretty darned clear though, that IF it spins/rotates like a galaxy, it MUST have a SMBH/IMBH in it's center!

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RussT
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Everything is, as it should be, otherwise, it wouldn't be!

RussT - it seems you are the only one confused by what I said and I am not willing to continue this petty discussion with you.

Back to the original topic:

At the moment, black holes are of great interest due to their feedback mechanisms, which may help to solve a number of conundrums with not only galaxy evolution, but galaxy cluster evolution. For example, the Chandra X-ray telescope has discovered the jets coming from active galaxies at the centre of some clusters blow holes in the surrounding intracluster medium (ICM; see e.g. here and this press release and this one too). These outbursts heat the surrounding ICM and stop gas cooling and flowing into the central galaxy to form stars. On a smaller scale, these outbursts can also stir up the hot gas in ellipticals (see e.g. here) again preventing the gas from cooling.

LOL...Great tactic...label me confused, after I just clarified this perfectly, and then "Dismiss"

Uh, who's confused???

What in the world does AGN have to do with "Galaxy Formation"?
OR did you mean Quasars?

Do galaxies start out as Quasars and 'step down' to AGN's of Seyfert II's and I's, then to just HSB's without a bulge to cause 'jets', then to LSB's "In the Early Universe" where the mass of the SMBH's is 'trending to less massive'?

Are you referring to some 'steady state' formation process?

Was the Milky Way Ever an AGN? Quasar?

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RussT
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Everything is, as it should be, otherwise, it wouldn't be!

I meant exactly what I wrote, and since the OP asked about the effects of a black holes on both galaxy formation and evolution, I think my post was fairly well on topic.

I have no idea what you are talking about. Can you be clearer please? (maybe in your own thread)

I'm not sure what you mean by this.

There was another thread on this which parejkoj linked to in a previous post. I suggest you read that thread and ask questions there.

And, here was a relevant post from that thread:

Is the Milky way a Quasar?

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So basically what you guys are saying is all galaxies have a central black hole, however it may not be considered "super-massive"? Please correct me, if I have any misconceptions.

__________________
The first principle is that you must not fool yourself - and you are the easiest person to fool.
~~~ Richard Feynman ~~~
It is imperative in science to doubt.
~~~ Richard Feynman ~~~
Common sense is not so common
~~~ Voltaire ~~~

I am not sure you can say with certainty that all galaxies have a central black hole, since we haven't observed every galaxy. I don't think there are any theoretical reasons to suspect that galaxies cannot form without a black hole at the centre, although modelling of galaxy formation/evolution is still a very active ongoing area of research!

However, you can say for certain that not all galaxies host a central SMBH since there are observations which show this.

Okay, so you're saying that it's theoretically possible for a galaxy not to have a central black hole, but we currently haven't observed any such galaxies?

__________________
The first principle is that you must not fool yourself - and you are the easiest person to fool.
~~~ Richard Feynman ~~~
It is imperative in science to doubt.
~~~ Richard Feynman ~~~
Common sense is not so common
~~~ Voltaire ~~~

Better: "The upper-limits from the best measurements of the masses of central objects in some galaxies is consistent with that central object being very small. There are also objects (such as irregulars like the Magellanic clouds) where there is no evidence for a central massive object, nor any strong a-priori reason to suspect that one exists. There is also no theoretical reason to believe that all galaxies must have a central massive object, and there are strong theoretical reasons to believe that all bulge-dominated objects do, and that the mass of their central object is correlated with the mass of the bulge."

Pedantic enough for you?

I'm not being flippant here, just trying to be explicit about what we do and don't know about galaxy formation and evolution. Oh, and you can quote me on that!

And just for further clarification, a few thousand to a few tens of thousands of solar masses is not called "supermassive." Those would be "intermediate mass black holes" and we don't yet have solid evidence for much of anything in that range. Most such observations are upper-limits, meaning the object could well be much smaller.

__________________
"What do you care what other people think?" -- Richard Feynman
"For a successful technology, reality must take precedence over public relations, for nature cannot be fooled." -- Feynman, at the conclusion of his Challenger report