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CrackerMcGinger
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I've been thinking for awhile now, and I still don't understand how these types of black holes form, since they can't form by conventional means.
CrackerMcGinger said:I've been thinking for awhile now
CrackerMcGinger said:they can't form by conventional means.
The most accepted explanation on how stellar black holes and SMBH that do not form in galactic center's.PeterDonis said:What do you mean by "conventional means"?
CrackerMcGinger said:The most accepted explanation on how stellar black holes and SMBH that do not form in galactic center's.
I might be a little tired... so, what do you mean by that?PeterDonis said:If you claim that SMBH in galactic centers cannot form by this means, you should be able to state briefly what this means is.
CrackerMcGinger said:what do you mean by that?
CrackerMcGinger said:they can't form by conventional means.
CrackerMcGinger said:If we figure out the most logical way black holes form that would be the most regular way that they can form, but that means the SMBH's form either differently or undergo changes that stellar black holes don't undergo.
CrackerMcGinger said:I also think that SMBH's in galactic cores have a less intense gravity well than that of other SMBH's and maybe even some strong stellar black holes
Black holes usually consume most of the matter around it, if that was the case then I would assume that the galactic core would have a lot less matter, but it appears to me that is not the case. I think that the black hole is more spread out, affecting a larger area and therefore not having the same intensity as more compact ones.PeterDonis said:Why do you think that?
CrackerMcGinger said:Black holes usually consume most of the matter around it
CrackerMcGinger said:I think that the black hole is more spread out, affecting a larger area and therefore not having the same intensity as more compact ones.
You are trying to reason from very vague non-numeric descriptions, which is what's leading to the errors Peter points out. Think about this: a black hole with a mass of a few million suns can be surrounded by just less than a few million suns and still be said to have consumed most of the mass around it. Since you haven't specified how big the volume "around" the black hole is, and you don't know how many stars you expect to be left (only that it's less than a few million) you don't have any way to say whether there are more stars "around" the black hole at the galactic core than you expect. This is why you always need to find numbers and maths before you try to make predictions, I'm afraid.CrackerMcGinger said:Black holes usually consume most of the matter around it
CrackerMcGinger said:can someone else describe the causes that link every known galaxy to a SMBH
CrackerMcGinger said:and why these black holes are different from stellar ones, other than the obvious fact that they are more powerful.
CrackerMcGinger said:I don't know how to explain what I'm trying to say without using my own drawing's.
CrackerMcGinger said:can someone else describe the causes that link every known galaxy to a SMBH
rootone said:This leaves two reasonable possibilities:
ebos said:Right now there is a medium sized black hole orbiting the SMBH at the Milky Way's center.
Have you checked for reports on gravitational lensing that could support his statement?nortonian said:I am unable to find anything that supports your statement. Can you cite something?
We know several that most definitely do not have SMBH at center. Like neither Magellanic cloud, nor Triangulum galaxy.PeterDonis said:We don't know that every known galaxy has a SMBH at its center.
Centrally symmetric mass distribution cannot emit gravity waves even when changing. The asymmetry of a binary black hole merging is what produces changing quadrupole moment and allows emission of gravity waves.Chronos said:LIGO has the potential for detecting direct collapse black holes. They should produce gravitational waves of measurable strength.
ebos said:Right now there is a medium sized black hole orbiting the SMBH at the Milky Way's center.
CrackerMcGinger said:Have you checked for reports on gravitational lensing that could support his statement?
You may find this of interest; http://arxiv.org/abs/1502.04125, Gravitational Waves from Direct Collapse Black Holes Formationsnorkack said:Centrally symmetric mass distribution cannot emit gravity waves even when changing. The asymmetry of a binary black hole merging is what produces changing quadrupole moment and allows emission of gravity waves.
true, but if their is no definite statement wouldn't an unusual gravitational reading be the next best thing?davenn said:he may well be right, but I would prefer a specific scientific reference related directly to his claim
Astronomers find evidence for 'direct collapse' black hole
Astronomers Aaron Smith and Volker Bromm of The University of Texas at Austin, working with Avi Loeb of the Harvard-Smithsonian Center for Astrophysics, have discovered evidence for an unusual kind of black hole born extremely early in the universe. They showed that a recently discovered unusual source of intense radiation is likely powered by a "direct-collapse black hole," a type of object predicted by theorists more than a decade ago. Their work is published today in the journal Monthly Notices of the Royal Astronomical Society.
Source: Astronomers find evidence for 'direct collapse' black hole - Royal Astronomical Society
I can't say for sure that that's wrong, but it seems unlikely since the orbits of the stars closest to the SMBH have been mapped in some detail and I do not recall that including any evidence that they were being perturbed by a much more massive object other than the SMBH itself. Of course, that would depend somewhat on what you mean by "medium sized". If it's something only a modest number of solar masses then it might not show up.ebos said:Right now there is a medium sized black hole orbiting the SMBH at the Milky Way's center.