All Topics  
Computation

 

 
   Email Print
   Bookmark   Link
 

 

Computation
 
 
  Topics Computation Topic Home

Computation is a general term for any type of information processing
Information processing

Information processing is the change of information in any manner detectable by an observation. As such, it is a Process which describes everything which happens in the universe, from the falling of a rock to the printing of a text file from a digital computer system....
. This includes phenomena ranging from human thinking to calculations with a more narrow meaning. Computation is a process following a well-defined model
Model (abstract)

In mathematical logic, the formal languages, formal systems, and theory which are studied have no meaningful content until they are given an interpretation within some other system....
 that is understood and can be expressed in an algorithm
Algorithm

In mathematics, computing, linguistics and related subjects, an algorithm is a sequence of finite instructions, often used for calculation and data processing....
, protocol
Protocol (computing)

In computer science, a protocol is a convention or standard that controls or enables the connection, communication, and data transfer between computing endpoints....
, network topology
Network topology

Network topology is the study of the arrangement or mapping of the elements of a Computer networking, especially the physical and logical interconnections between nodes....
, etc. Computation is also a major subject matter of computer science
Computer science

Computer science is the study of the theoretical foundations of information and computation, and of practical techniques for their implementation and application in computer systems....
: it investigates what can or cannot be done in a computational manner.

lass="link1" onMouseover='showByLink("m317667",this)' onMouseout='hide("m317667")'href="http://www.absoluteastronomy.com/topics/Evolutionary_computation">Evolutionary computation
Evolutionary computation

In computer science evolutionary computation is a subfield of artificial intelligence that involves combinatorial optimization problems.Evolutionary computation uses iterative progress, such as growth or development in a population....
), including those that are more naturally described by analog models of computation (for example, Artificial neural network
Artificial neural network

An artificial neural network , often just called a "neural network" , is a mathematical model or computational model based on biological neural networks....
).






Discussion
Ask a question about 'Computation'
Start a new discussion about 'Computation'
Answer questions from other users
Full Discussion Forum



Encyclopedia


Computation is a general term for any type of information processing
Information processing

Information processing is the change of information in any manner detectable by an observation. As such, it is a Process which describes everything which happens in the universe, from the falling of a rock to the printing of a text file from a digital computer system....
. This includes phenomena ranging from human thinking to calculations with a more narrow meaning. Computation is a process following a well-defined model
Model (abstract)

In mathematical logic, the formal languages, formal systems, and theory which are studied have no meaningful content until they are given an interpretation within some other system....
 that is understood and can be expressed in an algorithm
Algorithm

In mathematics, computing, linguistics and related subjects, an algorithm is a sequence of finite instructions, often used for calculation and data processing....
, protocol
Protocol (computing)

In computer science, a protocol is a convention or standard that controls or enables the connection, communication, and data transfer between computing endpoints....
, network topology
Network topology

Network topology is the study of the arrangement or mapping of the elements of a Computer networking, especially the physical and logical interconnections between nodes....
, etc. Computation is also a major subject matter of computer science
Computer science

Computer science is the study of the theoretical foundations of information and computation, and of practical techniques for their implementation and application in computer systems....
: it investigates what can or cannot be done in a computational manner.

Classes of computation


Computation can be classified by at least three orthogonal criteria: digital
Digital

A digital system uses discrete values, usually but not always symbolized numerically to represent information for input, processing, transmission, storage, etc....
 vs analog, sequential vs parallel vs concurrent, batch
Batch processing

Batch processing is execution of a series of Computer programs on a computer without human interaction.Batch jobs are set up so they can be run to completion without human interaction, so all input data is preselected through Script s or command-line parameters....
 vs interactive
Interactive computation

Interactive computation involves communication with the external world during the computation. This is in contrast to the traditional understanding of computation which assumes a simple interface between a computing agent and its environment, consisting in asking a question and generating an answer ....
.

In practice, digital computation is often used to simulate natural processes (for example, Evolutionary computation
Evolutionary computation

In computer science evolutionary computation is a subfield of artificial intelligence that involves combinatorial optimization problems.Evolutionary computation uses iterative progress, such as growth or development in a population....
), including those that are more naturally described by analog models of computation (for example, Artificial neural network
Artificial neural network

An artificial neural network , often just called a "neural network" , is a mathematical model or computational model based on biological neural networks....
). In this situation, it is important to distinguish between the mechanism of computation and the simulated model.

Computations as a physical phenomenon


A computation can be seen as a purely physical phenomenon occurring inside a closed physical system
Physical system

In physics the word system has a technical meaning, namely, it is the portion of the physical universe chosen for analysis. Everything outside the system is known as the environment, which in analysis is ignored except for its effects on the system....
 called a computer
Computer

A computer is a machine that manipulates Data according to a list of Code .The first devices that resemble modern computers date to the mid-20th century , although the computer concept and various machines similar to computers existed earlier....
. Examples of such physical systems include digital computers, quantum computer
Quantum computer

A quantum computer is a device for computation that makes direct use of quantum mechanical phenomena, such as quantum superposition and quantum entanglement, to perform operations on data....
s, DNA computers, molecular computer
Molecular computer

Molecular computers are massively parallel computers taking advantage of the computational power of molecules .Molectronics specifically refers to the sub-field of physics which addresses the computational potential of atomic arrangements....
s, analog computer
Analog computer

An analog computer is a form of computer that uses continuous physical phenomena such as electrical, mechanical, or hydraulic quantities to model the problem being solved....
s or wetware computer
Wetware computer

A wetware computer is an biological matter computer built from living neurons. , at the Georgia Institute of Technology, is the primary researcher driving the creation of these artificially constructed, but still organic brains....
s. This point of view is the one adopted by the branch of theoretical physics called the physics of computation
Physics of computation

The study of the physics of computation relates to understanding the fundamental physical limits of computers. This field has led to the investigation of how thermodynamics limits information processing, the understanding of chaos and dynamical systems, and a rapidly growing effort to invent new quantum computers....
.

An even more radical point of view is the postulate of digital physics
Digital physics

In physics and cosmology, digital physics is a collection of theoretical perspectives that start by assuming that the universe is, at heart, describable by information, and is therefore Computability theory ....
 that the evolution of the universe itself is a computation - Pancomputationalism
Pancomputationalism

Pancomputationalism is a view that the universe is a huge computational machine or rather a network of computational processes which following fundamental physical laws compute its own next state from the current one....
.

Mathematical models of computation


In the theory of computation
Theory of computation

The theory of computation is the branch of computer science that deals with whether and how efficiently problems can be solved on a model of computation, using an algorithm....
, a diversity of mathematical models of computers and their software are defined. A computation is considered as the evolution over discrete time epochs of such a model. Typical mathematical models of computers are the following:
  • Turing Machine
    Turing machine

    Turing machines are basic abstract symbol-manipulating devices which, despite their simplicity, can be adapted to simulate the logic of any computer algorithm....
  • Push-down automaton
  • Finite state automaton
Typical mathematical models of computer software are the following:
  • Formal grammar
    Formal grammar

    In formal language theory, grammars, also called formal grammars or generative grammars, are a formalism used to describe formal languages – i.e....
  • Recursive function
    Recursive function

    Recursive function may refer to:* Recursion : a procedure or subroutine, implemented in a programming language, whose implementation references itself...
  • Computable and non-computable functions
Different mathematical models of computers (as well as programming languages) can be classified according to their expressive power, see, for example, the Chomsky hierarchy
Chomsky hierarchy

Within the field of computer science, specifically in the area of formal languages, the Chomsky hierarchy is a containment hierarchy of classes of formal grammars....
. There are also other classifications of computations than the Chomsky hierarchy.

History


The word computation has an archaic meaning (from its Latin etymological roots), but the word has come back in use with the arising of a new scientific discipline: computer science
Computer science

Computer science is the study of the theoretical foundations of information and computation, and of practical techniques for their implementation and application in computer systems....
.

See also

  • Computing
    Computing

    Computing is usually defined as the activity of using and developing computer technology, computer hardware and computer software. It is the computer-specific part of information technology....
  • Physical information
    Physical information

    In physics, physical information refers generally to the information that is contained in a physical system. Its usage in quantum mechanics is important, for example in the concept of quantum entanglement to describe effectively direct or causality relationships between apparently distinct or spatially separated particles....
  • Real computation
    Real computation

    In computability theory, the theory of real computation deals with hypothetical computing machines using infinite-precision real numbers. They are given this name because they operate on the set of real numbers....
  • Reversible computation
  • Theory of computation
    Theory of computation

    The theory of computation is the branch of computer science that deals with whether and how efficiently problems can be solved on a model of computation, using an algorithm....
  • Hypercomputation
    Hypercomputation

    Hypercomputation refers to various hypothetical methods for the computation of non-Computable functions . The term was first introduced in 1999 by Jack Copeland and Diane Proudfoot....
  • Pancomputationalism
    Pancomputationalism

    Pancomputationalism is a view that the universe is a huge computational machine or rather a network of computational processes which following fundamental physical laws compute its own next state from the current one....