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Black Hole

Quantum Physics And Black Holes

All that has been said so far involves black holes as described by the general theory of relativity. However, in the realm of the very small, quantum mechanics has proved to be the proper theory to describe the physical world. To date, no one has successfully combined general relativity with quantum mechanics to produce a fully consistent theory of quantum gravity; however, in 1974, British physicist Stephen Hawking (1942–) suggested that quantum principles showed that a black hole should radiate energy like a perfect radiator having a temperature inversely proportional to its mass. This radiation—termed Hawking radiation—does not come about by the conventional departure of photons from the black hole's surface—which is impossible—but as a result of certain effects predicted by quantum physics. While the amount of radiation for any astrophysical black hole is very small (e.g., the radiation temperature for a black hole with the mass of the Sun would be 10-7K), the suggestion that loss of energy from a black hole was possible at all was revolutionary. It suggested a link between quantum theory and general relativity, and has spawned a host of new ideas expanding the relationship between the two theories. It is the ability of a black hole to lose mass via Hawking radiation (i.e., to evaporate) that prevents microscopic black holes, such as those that physicists hope to produce at CERN, from swallowing up the earth. These black holes evaporate faster than they can grow.

George W. Collins, II



Hawking, Stephen. W. The Illustrated A Brief History of Time. 2nd ed. New York: Bantam Books, 2001.


Cowan, John. "Supernova Birth for a Black Hole." Nature. (September 9, 1999): 124–125.

Glanz, James. "Evidence Points to Black Hole At Center of the Milky Way." New York Times. October 17, 2002.

Irion, Robert. "Galaxies, Black Holes Shared Their Youths." Science. (June 16, 2000): 1946–1947.

Johnson, George. "Physicists Strive to Build a Black Hole." New York Times. September 11, 2001.


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Binary system

—Any system of two stellar-like objects that orbit one another under the influence of their combined gravity.


—A large collection of stars and clusters of stars, containing anywhere from a few million to a few trillion stars.

General relativity

—A theory of gravity put forth by Albert Einstein in 1915 that basically describes gravity as a distortion of space-time by the presence of matter.

Interstellar material

—Any material that resides between the stars. It makes up the material from which new stars form.

Perfect radiator

—Also known as a black body (not to be confused with a black hole). Any object that absorbs all radiant energy that falls upon it and subsequently re-radiates that energy. The radiated energy can be characterized by a single dependant variable, the temperature.

Quantum gravity

—A theory resulting from the application of quantum principles to interaction between two objects normally attributed to gravity.

Quantum mechanics

—The theory that has been developed from Max Planck's quantum principle to describe the physics of the very small. The quantum principle basically states that energy only comes in certain indivisible amounts designated as quanta. Any physical interaction in which energy is exchanged can only exchange integral numbers of quanta.

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Science EncyclopediaScience & Philosophy: Bilateral symmetry to Boolean algebraBlack Hole - The Event Horizon, Detection Of Black Holes, Centerpiece Of The Galaxy, Quantum Physics And Black Holes