Black holes and star formation

Feb 09, 2012
An optical image of the "Antennae" galaxies. New research on interacting galaxies finds that interactions can stimulate bursts of star formation in the objects and also prompt the nuclear black hole to accrete material and become active. Credit: Hubble Space Telescope

(PhysOrg.com) -- It has long been recognized that galaxy mergers or even close interactions can play a vital role in shaping the morphology of galaxies. One way they can do so, it is thought, is by triggering bursts of star formation. But exactly how a collision produces new stars is not clear: sometimes star formation activity is seen all across an interacting galaxy, but in other cases it is localized to a region around the galactic nucleus.

Galaxy mergers and close interactions are also thought to drive the growth of central and their high-energy activity. The collision prompts material to fall into the massive central region, stimulating the black hole to become what is called an active galactic nucleus (AGN). Sorting out these two effects of a merger is a key issue in modern astronomy, and is associated with determining if and how star burst activity is connected to the growth of the central black hole.

CfA astronomers Xin Liu and Yue Shen, together with a colleague, studied a set of 1286 pairs of AGN, presumably interacting with one another, that were observed optically in a large, systematic survey of galaxies.

They used the strength of ionized oxygen and hydrogen emission lines to quantify the black hole and/or star formation activity in these sources, and then compared the results to strengths seen in single AGN that are not interacting. Writing in one paper of a series on this subject, they report that tidal interactions enhance both black hole accretion and , especially in closer pairs.

They also find that visible tidal features can be a misleading measure of an interaction - some AGN pairs may be interacting yet show no tidal features, perhaps because of the galaxy composition or details of the collision.

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ant_oacute_nio354
Feb 09, 2012
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Tuxford
1 / 5 (4) Feb 09, 2012
Not so confusing if you consider a 'continuous creation' model as the explanation. Be brave, and give it a try.

Suppose the presence of high mass density regions begets the creation of more matter in the same region. Of course, AGN's are the extreme case, producing the vast majority of new matter. Does this not fit the description given in this article???
ccr5Delta32
5 / 5 (4) Feb 09, 2012
high mass density regions begets the creation of more matter in the same region.


It's a bit vague "begets" .It would be brave of you to predict not postdict the nature composition H,He,Li ratios of this begotten matter emerging in a gravitational gradient .Something that could be tested with spectral analysis of the stars
Einstein said "light will be deflected by the sun's gravitational field and by how much" ,had it not being he would have ditched the theory start over or gone mad . That's brave and more importantly honest
Deesky
5 / 5 (5) Feb 09, 2012
Not so confusing if you consider a 'continuous creation' model as the explanation.

Can you direct me to a link to a scientific paper that discusses this model?

Be brave, and give it a try.

Always willing to read about a new scientific theory. Link?

Suppose the presence of high mass density regions begets the creation of more matter in the same region.

Why would I suppose that? Is that a part of the 'model'?

Does this not fit the description given in this article???

It's irrelevant whether mere words and baseless suppositions fit, without some kind of theoretical basis behind them. Does your 'continuous creation model' have the bona fides?
Tuxford
1 / 5 (5) Feb 10, 2012
Deesky,
It is not my model, but after reflecting on it for more than a year, I concluded that it is a worth consideration. It is simply difficult to approach, as it is radically different than current conclusions.

http://starburstf...l#papers

Yes, the physics model predicts the emergence of matter spontaneously, even in intergalactic space over time. However, the model also predicts this condition is greatly enhanced in stellar cores, or even much more in galactic core mother-stars (supermassive black holes). The model is derived from General Systems Theory, applied to physics.

Last year, LaViolette published a paper linking the last ice age event to changes in solar activity. His cosmology model links this change to the passage of the last cosmic ray superwave (now illuminating the Crab Nebula), from our galactic core star. The physics model predicts instability in the mother core star, as it grows over time, eventually becoming an AGN.
jsdarkdestruction
5 / 5 (4) Feb 10, 2012
you forget how laviolette believes in ancient aliens in that description tuxford. you also missed how he believes science and philosophy should be re-united and that astrology should be considered a scientific field.

all that is nonsense. he can say whatever he wants it doesnt make it true. yeah, lets say the reason we are so advanced is creatures in a spaceship, might as well say god did it like the creationists and be done with it. stop wasting our time please, paul laviolette is not a reputable source. he's just trying to cross all kinds of fields of science he doesnt understand and you admit you have no experience in any of this anyway.
Tuxford
1.7 / 5 (6) Feb 10, 2012
Destruction, Your comments are generally useless, except for the innocently ignorant. Why you insist on replying if you consider new ideas pointless. That you attack people without ever offering any technically relevant point, makes me think you are simply a government troll, bent on distracting the masses further into Big Bang fantasy in order to keep a classified physics out of the mainstream academia. If not that, then I must conclude even worse.

LaViolette's conclusions are very considered, with backup research. If anyone is truely interested in reality, rather than fantasy, then one has to break from what the irrationally rationale have proclaimed. Reality is much more interesting than what we have been led to believe.
jsdarkdestruction
5 / 5 (4) Feb 11, 2012
I have not proclaimed anything. I have examined the evidence and counter evidence. just like all the scientists you accuse of dishonesty. Paul laviolette is a crank tuxford. ancient aliens? come on man. thats sad. I can connect a bunch of fairy tails to a make believe scientific theory just like he can, anyone could.