| | [[Image:Iu8969hu.jpg|right|thumb|300px|Artist's conception of a binary system consisting of a black hole and a main sequence star. The black hole is drawing matter from the main sequence star via an [[accretion disk]] around it, and some of this matter forms a gas jet.]] | | [[Image:Iu8969hu.jpg|right|thumb|300px|Artist's conception of a binary system consisting of a black hole and a main sequence star. The black hole is drawing matter from the main sequence star via an [[accretion disk]] around it, and some of this matter forms a gas jet.]] |
| − | '''Black holes''' are theoretical entities which are suggested by the [[theory of relativity]]. They are postulated to be collapsed objects, usually [[stars]], which have so much mass that at a certain radius referred to as the Schwarzschild radius, there is an event horizon, beyond which the dilation of space-time due to the mass of the black hole results in all possible paths leading closer to the black hole. | + | '''Black holes''' are theoretical entities which cannot be directly observed and may not exist. Suggested by the controversial [[theory of relativity]] (see [[Counterexamples to Relativity), black holes are postulated to be collapsed objects, usually [[stars]], which have become so [[dense]] that within a certain radius their [[escape velocity]] exceeds the [[speed of light]]. Thus, they absorb all matter and energy within that radius. Light and matter can enter, but nothing can ever escape. |
| − | Black holes have become an increasingly popular topic for magazines, the science page of the [[New York Times]], and science fiction, as their nature results in a profound paradox. Using classical theory, black holes have been described using the "no hair theorem", which states that black holes can be described using mass, charge, and angular momentum, and are otherwise indistinguishable. This results in the Black hole information paradox, which is part of the incomplete understanding of the relationship between classical and quantum mechanics. | + | Black holes are increasingly favored by [[liberal]] publications, such as the science page of the [[New York Times]] and glossy magazines, as well as science fiction writers. As with the related theoretical concept of a "[[wormhole]]",<ref>The prediction of the existence of wormholes, and its naming in 1957, predates the prediction and naming (1967) of a black hole.[http://www.nytimes.com/2008/04/14/science/14wheeler.html?pagewanted=print]</ref> it is impossible to prove that no black hole exists anywhere, and thus they fail the [[falsifiability]] requirement of science. |