Types of Black Holes
There are four known, exact, black hole solutions to Einstein's equations, which describe gravity in General Relativity. Two of these (the Kerr and Kerr-Newman black holes) rotate. It is generally believed that every black hole decays rapidly to a stable black hole; and, by the no-hair theorem, that (modulo quantum fluctuations) stable black holes can be completely described at any moment in time by these eleven numbers:
- mass-energy M,
- linear momentum P (three components),
- angular momentum J (three components),
- position X (three components),
- electric charge Q.
These numbers represent the conserved attributes of an object which can be determined from a distance by examining its electromagnetic and gravitational fields. All other variations in the black hole will either escape to infinity or be swallowed up by the black hole. This is because anything happening inside the black hole horizon cannot affect events outside it.
In terms of these properties, the four types of stable black holes can be defined as follows:
| Nonrotating (J = 0) | Rotating (J > 0) | |
| Uncharged (Q = 0) | Schwarzschild | Kerr |
| Charged (Q ≠ 0) | Reissner-Nordström | Kerr-Newman |
Read more about this topic: Rotating Black Hole
Famous quotes containing the words black holes, types of, types, black and/or holes:
“Just like those other black holes from outer space, Hollywood is postmodern to this extent: it has no center, only a spreading dead zone of exhaustion, inertia, and brilliant decay.”
—Arthur Kroker (b. 1945)
“The wider the range of possibilities we offer children, the more intense will be their motivations and the richer their experiences. We must widen the range of topics and goals, the types of situations we offer and their degree of structure, the kinds and combinations of resources and materials, and the possible interactions with things, peers, and adults.”
—Loris Malaguzzi (1920–1994)
“The wider the range of possibilities we offer children, the more intense will be their motivations and the richer their experiences. We must widen the range of topics and goals, the types of situations we offer and their degree of structure, the kinds and combinations of resources and materials, and the possible interactions with things, peers, and adults.”
—Loris Malaguzzi (1920–1994)
“The desire of most parents is first and foremost to do what is best for their children. Every interview with a mother or father confirms this, every letter written by a parent breathes this deep-seated wish, “I hope I am doing the right thing for my child.” This is real and honest, and at the very base of parenthood.”
—Irma Simonton Black (20th century)
“But Father John went up,
And Father John went down;
And he wore small holes in his shoes,
And he wore large holes in his gown.”
—William Butler Yeats (1865–1939)