What percentage of the universe's baryonic matter is made up of black holes?
After reading a post from +From Quarks To Quasars
regarding black holes: "Stephen Hawking Bombshell: "Black Holes, As We Know Them, Do Not Exist", I went looking for the answer to: What percentage of the universe's matter is made up of black holes?
I couldn't find the answer, so I submitted the question tohttp://imagine.gsfc.nasa.gov/docs/ask_astro/ask_an_astronomer.html
Hans Krimm replied with the following:
"This is a good question. Here is my educated estimate, taking some
numbers from this site:http://hubblesite.org/explore_astronomy/black_holes/encyc_mod3_q7.html
First, consider stellar mass black holes, which are the remnants of very massive stars. Maybe one in a thousand stars becomes a black hole.
Taking that the mass of such a black hole is roughly ten times the mass of an average star, means that (1/1000)*(10) = 0.01, or one percent of the mass of stars is black holes.
Second, consider the supermassive black holes in the center of most, and probably all galaxies. The masses of these beasts can vary quite a bit, but a reasonable order of magnitude is 100 million times the mass of an average star. Since a typical galaxy contains 100 billion stars, this means that (100 million)/(100 billion) = 0.001, or a tenth of a percent of the mass of a galaxy is in the central supermassive black hole.
There may also be intermediate mass black holes, but these are probably rare and would be an even smaller contributor.
So taking these rough order of magnitude estimates together, one can see that black holes account for somewhere around 0.1 - 1% of the "normal" mass of the universe. But remember that "normal" matter like atoms, is itself only about 5% of the total mass of the universe.
Hans Krimm for Ask an Astrophysicist "
Thank you Mr. Krimm.
It's hard to say if 0.1 to 1.0 % of baryonic matter is a lot or not. Our own star makes up 99.8 percent of the mass of our solar system.
It takes suns 3 solar masses or more to turn into black holes.
How much of the stars mass is thrown into space, and how much is captured in the black hole?
How much is turned into energy? Supernova's are seen for very large distances. Does this energy represent a significant amount of it's mass?
That gets me wondering what kind of stars are the most plentiful, and what are the least, and what are the distribution in the universe? Is our Milky way different from the Andromeda Galaxy? Or older galaxies?
The problem with having one question answered is it begets another ten questions.