Dark matter and Black hole

[Nirmal]

My theory about  Black holes is that they are made of Dark black matter. When normal matter enters the event horizon; they get transformed in to Dark Matter.

So my proposal here is that the Dark Matter is not a hallow around the galaxies but highly concentrated lumps( Black Holes) in the galaxies.

1. This explains  the additional mass of galaxies

2. Black holes are black not because light can't escape it but there is no source that can produce light in a black holes

 

Edited December 29, 2017 by Nirmal
I intended to say Dark matter but by mistake typed it as Black matter

[radonek]

Light-stopping gravity is defining property of black holes. You are really trying to define very different new kind of stellar object. And prety silly one at that, you are basicaly saying that dark matter is made of objects made of dark matter. Wow. Never thought of that.

[ARS]

Black hole does glow when they are absorbing matter from poor stars that got on their way. Also, we can see stuff because light is reflected from them into our eyes. Black hole does not reflect light since black hole prevents light from escaping, thereby, no light being reflected back. Mind you, black hole gravitational force is so powerful it can bend light and create gravitational lensing. See this:

https://upload.wikimedia.org/wikipedia/commons/thumb/0/03/Black_hole_lensing_web.gif/220px-Black_hole_lensing_web.gif

Edited December 29, 2017 by ARS

[cubinator]

(Gravitational lensing of a background galaxy by a foreground one)

By black matter, you must mean what is more commonly called dark matter?

Relativity is a pretty solid concept, and we know well what happens to light as it passes through a gravitational field from observation of large galaxies. Black holes are black because any light that falls in doesn't have enough velocity to come out again. They (the black part at least) are not made of matter, but are a region of spacetime where the escape velocity is greater than the speed of light.

The mysterious additional mass of galaxies is problematic not only because of how much there is, but how it affects the movement of stars. We see stars in the outer edges of galaxies moving a lot faster than they should be if there was only normal matter, while stars in the core move more like we'd expect. This doesn't work out if the mass is concentrated in a central black hole as you (and traditional physics) predict. There seems to be extra mass in the outer regions of galaxies, which we call dark matter. Dark matter also seems to exist way out in intergalactic space in great quantities, so it must not be highly concentrated. We know this is true because we can see gravitational lensing around seemingly empty space on galactic scales.

Edited December 28, 2017 by cubinator

[K^2]

First, just to be picky, you have a hypothesis, not a theory. Theory requires rigorous testing.

But more importantly and on point, your hypothesis is thoroughly disproven by available data. While black holes accounting for dark matter is an idea that has been put forward, the problem is that we know only about super-massive black holes at the centers of galaxies that have a chance to contribute enough. Gravitational lensing experiments, however, show that dark matter is distributed throughout the galaxy. Distribution is believed to be slightly different than that of luminous matter, but mostly along the same lines. Which means that a few super-massive black holes can't account for it. And regular sized-black holes we've observed can't account for all the necessary mass - they'd have to be far more common than we observe them to be. Finally, there has been proposals that there are tons and tons of tiny, undetectably small black holes buzzing about the galaxy. However, we've not observed any, and there are no mechanisms to explain their formation. So that seems to be out as well.

Consequently, black holes do not explain discrepancy between luminous and dark matter content of the universe. Your hypothesis is busted by SCIENCE! But it's not a stupid idea, people did think about it, just happens not to be the case.

Edited December 28, 2017 by K^2

[PB666]

15 hours ago, K^2 said:

Gravitational lensing experiments, however, show that dark matter is distributed throughout the galaxy. Distribution is believed to be slightly different than that of luminous matter, but mostly along the same lines. Which means that a few super-massive black holes can't account for it. And regular sized-black holes we've observed can't account for all the necessary mass - they'd have to be far more common than we observe them to be.

^

Also there is an open thread on the discussion of dark gravity and this thread should be merged into it.

 

[And to add to this, as one moves away from the galactic center the non-dark matter available to create black holes is not present in the density required. Its actually fairly easier to build a massive black hole than tiny black holes and tiny black holes are much less stable. For a typical black hole generating event to create a tiny black hole would take more time than the current age of the universe. ]

 

[Nirmal]

Thank you all for the valuable inputs. I would like to continue this discussion about the Dark matter and Black holes.

couple of reasons

1  The presence of Dark matter is identified by observing the effects. Which cannot pin point the location. It only gives a general idea of its presence

2  Number of Black hole in a galaxy or outside is again very difficult to accurately estimate.  The type - Stellar Black holes  for instance which can be approximately numbered is also very vague. for example the number in milky way could vary between 1 million to a billion ( according to one estimate ). This is just one type. So our understanding is not clear on the number of black holes in a Galaxy so how can we estimate the total mass and say that what we see cannot account for it all.  The mass estimated by gravitational methods would be inclusive of the mass of all the black hole( which are known and many which are unknown) in that galaxy. 

   

[cubinator]

38 minutes ago, Nirmal said:

Thank you all for the valuable inputs. I would like to continue this discussion about the Dark matter and Black holes.

couple of reasons

1  The presence of Dark matter is identified by observing the effects. Which cannot pin point the location. It only gives a general idea of its presence

But the lensing effects also give an idea of the size of an object. The black hole at the center of Andromeda, for instance, creates a lot of lensing but on a very small scale. A galaxy cluster with dark matter in it shows lensing on a very large scale.

 

[Green Baron]

12 hours ago, Nirmal said:

1  The presence of Dark matter is identified by observing the effects. Which cannot pin point the location. It only gives a general idea of its presence

I don't quite understand what you mean with "general idea". Do you think that dark matter must be concentrated like the light one, in stars, planets, etc. ?

Quote

so how can we estimate the total mass and say that what we see cannot account for it all.  The mass estimated by gravitational methods would be inclusive of the mass of all the black hole

The standard model of cosmology says 5% "normal" baryonic matter, 70% dark energy, 25% dark matter (+/-). Black holes, neutron stars and the likes belong to the "normal" stuff. And yes, that is a view on the level of galaxies and larger i think (but do not know) simply because our observation methods aren't fine grained enough yet.

Dark matter distribution is estimated by observation (grav. lensing, cosmic microwace-background) as well as theoretic modeling.

Edited December 30, 2017 by Green Baron

[PB666]

47 minutes ago, Green Baron said:

The standard model of cosmology says 5% "normal" baryonic matter, 70% dark energy, 25% dark matter (+/-). Black holes, neutron stars and the likes belong to the "normal" stuff. And yes, that is a view on the level of galaxies and larger i think (but do not know) simply because our observation methods aren't fine grained enough yet.

That is a sort of subjective classification. The are black dwarfs that we cannot see that also are not large enough to lens. It not so much what the classes, its the fact that where ever you draw the lines, there is still an excess of unexplained gravity around galaxies. I'm inclined to believe its the underlying physics that is estranged. Oh and if I am not mistaken a black hole technically non-baryonic " The information that is lost includes every quantity that cannot be measured far away from the black hole horizon, including approximately conserved quantum numbers such as the total baryon number and lepton number." And the charge and rotation of a black hole is possible an effect of the surface state, the plasma that circles the black hole can loose its electrons. I think the reason we study black holes is to obtain these answers. 

If you define a black hole by its outward appearance, it could be described as collectively baryonic, but its outward appearance is not the hole, the hole itself projects no appearance. Therefore if you remove all of these superficial traits what is left is a Einsteinian singularity, that is to say whats inside it is its own universe that is immaterial to our point of view . . . .it could be energy for all we know. . . .  and what we see does not have any characteristics of our universe other than commonality with other black holes.

[sevenperforce]

@Nirmal -- this is not a bad idea. Quite the opposite; it's a very good idea. However, it's not a new idea, not in physics. Other individuals have already proposed this sort of idea, numerous times, and so there's a broad body of research and investigation as to whether this might actually be the case (and, if so, what we would expect to see).

So don't take it personally; this is just stuff that I've already looked at pretty intensely.

17 hours ago, Nirmal said:

The presence of Dark matter is identified by observing the effects. Which cannot pin point the location. It only gives a general idea of its presence

That's a common misconception when people are just starting to learn about dark matter. Although dark matter does not emit light of its own, dark matter CAN be mapped using gravitational lensing, just like we can chart the bottom of a lake using sonar even though we can't see it. And because galaxies are dynamic, not static, we can use that mapping to see how dark matter behaves...how it moves, how it interacts with the galaxies it is in. What we know about dark matter from these observations pretty neatly rules out baryonic matter.

Baryonic matter interacts electromagnetically. Dark matter does not. If something doesn't walk like a duck, or look like a duck, or quack like a duck...well, it's probably not any kind of duck we've ever found before.

17 hours ago, Nirmal said:

Number of Black hole in a galaxy or outside is again very difficult to accurately estimate.  The type - Stellar Black holes  for instance which can be approximately numbered is also very vague. for example the number in milky way could vary between 1 million to a billion ( according to one estimate ). This is just one type. So our understanding is not clear on the number of black holes in a Galaxy so how can we estimate the total mass and say that what we see cannot account for it all.  The mass estimated by gravitational methods would be inclusive of the mass of all the black hole( which are known and many which are unknown) in that galaxy.    

Black holes are not found floating naked through the galaxy. They form during core-collapse supernovae and end up surrounded by dust clouds and accretion disks. They may be "black" in the sense that the object itself does not emit visible light (other than Hawking radiation), but they stick out like a sore thumb wherever they are found.

3 hours ago, PB666 said:

That is a sort of subjective classification. The are black dwarfs that we cannot see that also are not large enough to lens. It not so much what the classes, its the fact that where ever you draw the lines, there is still an excess of unexplained gravity around galaxies. I'm inclined to believe its the underlying physics that is estranged.

No problem with the underlying physics. The lensing observations of dark matter perfectly fit the required distribution of gravity in galaxies. And observations of the Bullet Cluster prove beyond reasonable doubt that the dark matter is actual stuff, not just some trick of spacetime.

3 hours ago, PB666 said:

Oh and if I am not mistaken a black hole technically non-baryonic " The information that is lost includes every quantity that cannot be measured far away from the black hole horizon, including approximately conserved quantum numbers such as the total baryon number and lepton number." And the charge and rotation of a black hole is possible an effect of the surface state, the plasma that circles the black hole can loose its electrons. I think the reason we study black holes is to obtain these answers. 

If you define a black hole by its outward appearance, it could be described as collectively baryonic, but its outward appearance is not the hole, the hole itself projects no appearance. Therefore if you remove all of these superficial traits what is left is a Einsteinian singularity, that is to say whats inside it is its own universe that is immaterial to our point of view . . . .it could be energy for all we know. . . .  and what we see does not have any characteristics of our universe other than commonality with other black holes.

Au contraire; a black hole is nonbaryonic by its outward appearance, but it is baryonic in origin, so we classify it with baryonic matter.

[PB666]

5 hours ago, sevenperforce said:

@Nirmal -- this is not a bad idea. Quite the opposite; it's a very good idea. However, it's not a new idea, not in physics. Other individuals have already proposed this sort of idea, numerous times, and so there's a broad body of research and investigation as to whether this might actually be the case (and, if so, what we would expect to see).

So don't take it personally; this is just stuff that I've already looked at pretty intensely.

That's a common misconception when people are just starting to learn about dark matter. Although dark matter does not emit light of its own, dark matter CAN be mapped using gravitational lensing, just like we can chart the bottom of a lake using sonar even though we can't see it. And because galaxies are dynamic, not static, we can use that mapping to see how dark matter behaves...how it moves, how it interacts with the galaxies it is in. What we know about dark matter from these observations pretty neatly rules out baryonic matter.

Baryonic matter interacts electromagnetically. Dark matter does not. If something doesn't walk like a duck, or look like a duck, or quack like a duck...well, it's probably not any kind of duck we've ever found before.

Black holes are not found floating naked through the galaxy. They form during core-collapse supernovae and end up surrounded by dust clouds and accretion disks. They may be "black" in the sense that the object itself does not emit visible light (other than Hawking radiation), but they stick out like a sore thumb wherever they are found.

No problem with the underlying physics. The lensing observations of dark matter perfectly fit the required distribution of gravity in galaxies. And observations of the Bullet Cluster prove beyond reasonable doubt that the dark matter is actual stuff, not just some trick of spacetime.

Au contraire; a black hole is nonbaryonic by its outward appearance, but it is baryonic in origin, so we classify it with baryonic matter.

Everything is something else in its origin, As I said it is only superficially baryonic due the events close to the event horizon.