Massive black holes have been found at the centres of almost all galaxies, where the largest galaxies -- who are also the ones embedded in the largest halos of dark matter -- harbour the most massive black holes. This led to the speculation that there is a direct link between dark matter and black holes, i.e. that exotic physics controls the growth of a black hole.
Scientists at the Max Planck Institute of Extraterrestrial Physics, the University Observatory Munich and the University of Texas in Austin have now conducted an extensive study of galaxies to prove that black hole mass is not directly related to the mass of the dark matter halo but rather seems to be determined by the formation of the galaxy bulge. Their findings are published Jan. 20, 2011 in journal Nature.
The Astronomical Research Center (A.R.C) mentioned that Galaxies, such as our own Milky Way, consist of billions of stars, as well as great amounts of gas and dust. Most of this can be observed at different wavelengths, from radio and infrared for cooler objects up to optical and X-rays for parts that have been heated to high temperatures. However, there are also two important components that do not emit any light and can only be inferred from their gravitational pull.
All galaxies are embedded in halos of so-called dark matter, which extends beyond the visible edge of the galaxy and dominates its total mass. This component cannot be observed directly, but can be measured through its effect on the motion of stars, gas and dust. The nature of this dark matter is still unknown, but scientists believe that it is made up of exotic particles unlike the normal (baryonic) matter, which we, the Earth, Sun and stars are made of.