Could Stellar Black Holes Account for Half of Dark Matter in the Universe?

[Imax]

Twenty first century dark matter reminds me of ninetieth century luminiferous aether. Without dark matter, current models of galaxies fall apart. What could happen if some of that dark matter mass was from stellar black holes?

The supermasssive black hole at the center of our galaxy, the Milky Way, is about 10% the mass of our galaxy. In current models, the universe is made up of about 5% matter, the stuff we can see, about 25% dark matter, the stuff we can’t see, and about 75% dark energy.

What would happen to current models if half the dark matter mass (i.e. 10% of the universe) was from stellar black holes? To me, that could mean that there could be a lot more stellar black holes than anticipated from the current model. It could mean that stellar back hole mass is about twice the mass of the universe as we can observe.

Within this model, the universe could be made up of about 5% matter, about 10% stellar black holes, about 15% dark matter, and about 75% dark energy.

 

[DaveC426913]

1] Mass concentrated at a point at the centre of a galaxy would not explain the anomalies. The anomalies suggest an excess of mass in a halo including the outer reaches of the galaxy. http://en.wikipedia.org/wiki/Galaxy_rotation_problem
2] Contrary to popular belief, black holes are very visible and have a distinctive radio signature.

 

[Imax]

Stellar black holes would not be concentrated to a center, but could be distributed throughout a galaxy.

 

[DaveC426913]

Stellar black holes would not be concentrated to a center, but could be distributed throughout a galaxy.

OK. And point 2?

 

[nicksauce]

This scenario has basically been ruled out by observations. See: http://en.wikipedia.org/wiki/Massive_compact_halo_object , in particular the "detection" section.

 

[nicksauce]

The supermasssive black hole at the center of our galaxy, the Milky Way, is about 10% the mass of our galaxy.

Where do you get this? Going by the wikipedia values, Sgr A* is about 4*10^6 solar masses, while the Milky Way is something like 7*10^11 solar masses.

 

[Janus]

Twenty first century dark matter reminds me of ninetieth century luminiferous aether.

There is a big difference between the aether and DM. The aether, when we went looking for it, was conspicuously absent, in that predictions using the model failed when it came to actual observation. Predictions based on the DM model however keep bearing fruit.

 

[Imax]

2) Contrary to popular belief, black holes are very visible and have a distinctive radio signature.

Possibly, but only for those black holes near matter. Other black holes could be invisible, with no distinct radio signature.

 

[DaveC426913]

Possibly, but only for those black holes near matter. Other black holes could be invisible, with no distinct radio signature.

All of them? That'd be a neat trick. The galaxy is permeated with dust and gas. Where in the galaxy are all thse expanses of uncharacteristically hard vacuum that these black holes gather?

 

[Nabeshin]

Possibly, but only for those black holes near matter. Other black holes could be invisible, with no distinct radio signature.

Also, does not the process of black hole formation necessitate that they exist in a nebulous environment?