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− | [[Image:Biophysics_of_computation_2.jpg|right|frame|<center>ISBN 0-19-510491-9</center>]] | + | [[Image:Biophysics_of_computation_version_2.jpg|right|frame]] |
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− | '''Computation''' is a general term for any type of [[information processing]] that can be represented mathematically. This includes phenomena ranging from simple calculations to human thinking. In a more narrow meaning, computation is a process following a well defined [[Model (abstract)|model]] that is understood and can be expressed in an [[algorithm]], [[Protocol (computing)|protocol]], [[network topology]], etc. | + | ==Origin== |
| + | from French ''computer'' or [[Latin]] ''computare'', from ''com''- ‘[[together]]’ + ''putare'' ‘to settle (an account). |
| + | *[http://en.wikipedia.org/wiki/15th_century 15th Century] |
| + | ==Definitions== |
| + | *1a : the act or [[action]] of computing : [[calculation]] |
| + | :b : the use or operation of a [[computer]] |
| + | *2: a system of [[Accounting|reckoning]] |
| + | ==Description== |
| + | '''Computation''' is any type of calculation or use of computing [[technology]] in [http://en.wikipedia.org/wiki/Information_processing information processing]. Computation is a [[process]] following a well-defined [[model]] understood and [[expressed]] as, for example, an [[algorithm]], or a protocol. Computation can be [[classified]] by mainly three unique criteria: digital versus analog, sequential versus parallel versus concurrent, batch versus interactive. |
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− | === Classes of computation ===
| + | In [[practice]], digital computation aids [[simulation]] of natural processes (for example, [http://en.wikipedia.org/wiki/Evolutionary_computation evolutionary computation]), including those that are naturally described by analog models of computation (for example, [http://en.wikipedia.org/wiki/Artificial_neural_network artificial neural network]). Otherwise, calculation is a term for the computation of [[numbers]], while computation is a wider reaching term for [[information]] processing in general.[http://en.wikipedia.org/wiki/Computation] |
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− | Computation can be classified by at least three orthogonal criteria: [[digital]] vs [[analog electronics|analog]], [[sequential]] vs [[parallel computation|parallel]], [[batch processing|batch]] vs [[interactive computation|interactive]].
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− | In practice, digital computation is often used to simulate natural processes (for example,
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− | [[Evolutionary computation]]), including those that are more naturally described by analog models of computation (for example, [[Artificial neural network]]). In this situation, it is important to distinguish between the mechanism of computation and the simulated model.
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− | === Computations as a physical phenomenon ===
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− | A computation can be seen as a purely physical phenomenon occurring inside a closed [[physical system]] called a [[computer]].
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− | Examples of such physical systems include [[digital computer]]s, [[quantum computer]]s, [[DNA computer]]s, [[molecular computer]]s, [[analog computer]]s or [[wetware computer]]s.
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− | This point of view is the one adopted by the branch of theoretical physics called the [[physics of computation]].
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− | An even more drastic point of view is the postulate of [[digital physics]] that the evolution of the universe itself is a computation.
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− | === Mathematical models of computation ===
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− | In the [[theory of computation]], mathematical models of computers are defined. A computation is the evolution over discrete time epochs of this model.
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− | Typical mathematical models of computers are the following:
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− | * [[Turing Machine]]
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− | * [[push-down automaton]]
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− | * [[Finite state automaton]]
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− | Different mathematical models of computers can be classified according to their expressive power, see the [[Chomsky hierarchy]].
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− | == History ==
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− | The word computation has an archaic meaning (from its [[Latin language|Latin]] etymological roots), but the word has come back in use with the arising of a new scientific discipline: [[computer science]].
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− | == See also ==
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− | * [[Computing]]
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− | * [[Physical information]]
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− | * [[Real computation]]
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− | * [[Reversible computation]]
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− | * [[Theory of computation]]
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− | * [[Physics of computation]]
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− | * [[Hypercomputation]]
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− | [[Category: General Reference]]
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| [[Category: Computer Science]] | | [[Category: Computer Science]] |