Universal Turing machine (nonfiction): Difference between revisions
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[[File:Universal Turing machine.svg|thumb|A Universal Turing machine '''U'''. '''U''' consists of a set of instructions in the table that can “execute” the correctly-formulated “code number” of any arbitrary Turing machine '''M''' on its tape. In some models, the head shuttles back and forth between various regions on the tape. In other models the head shuttles the tape back and forth.]]In [[computer science]], a '''Universal Turing machine''' ('''UTM''') is a Turing machine that can simulate an arbitrary Turing machine on arbitrary input. | [[File:Universal Turing machine.svg|thumb|A Universal Turing machine '''U'''. '''U''' consists of a set of instructions in the table that can “execute” the correctly-formulated “code number” of any arbitrary Turing machine '''M''' on its tape. In some models, the head shuttles back and forth between various regions on the tape. In other models the head shuttles the tape back and forth.]]In [[computer science]], a '''Universal Turing machine''' ('''UTM''') is a Turing machine that can simulate an arbitrary Turing machine on arbitrary input. | ||
The universal machine essentially achieves this by reading both the description of the machine to be simulated as well as the input thereof from its own tape. | The universal machine essentially achieves this by reading both the description of the machine to be simulated as well as the input thereof from its own tape. | ||
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It is also known as universal computing machine, universal machine (UM), machine U, U. | It is also known as universal computing machine, universal machine (UM), machine U, U. | ||
== | In terms of [[Computational complexity (nonfiction)|computational complexity]], a multi-tape universal Turing machine need only be slower by logarithmic factor compared to the machines it simulates. | ||
== In the News == | |||
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== Fiction cross-reference == | == Fiction cross-reference == | ||
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* [[Mathematics (nonfiction)]] | * [[Mathematics (nonfiction)]] | ||
External links: | |||
* [https://en.wikipedia.org/wiki/Universal_Turing_machine Universal Turing machine] @ Wikipedia | * [https://en.wikipedia.org/wiki/Universal_Turing_machine Universal Turing machine] @ Wikipedia | ||
Revision as of 06:40, 30 June 2016
In computer science, a Universal Turing machine (UTM) is a Turing machine that can simulate an arbitrary Turing machine on arbitrary input.
The universal machine essentially achieves this by reading both the description of the machine to be simulated as well as the input thereof from its own tape.
Alan Turing introduced this machine in 1936–1937.
This model is considered by some (for example, Martin Davis (2000)) to be the origin of the stored program computer—used by John von Neumann (1946) for the "Electronic Computing Instrument" that now bears von Neumann's name: the von Neumann architecture.
It is also known as universal computing machine, universal machine (UM), machine U, U.
In terms of computational complexity, a multi-tape universal Turing machine need only be slower by logarithmic factor compared to the machines it simulates.
In the News
Fiction cross-reference
Many scrying engines behave according to Universal Turing machine principles.
- Gnomon algorithm - a mathematical function which converts computation to force.
- Scrying engine - closely related to Universal Turing machines.
Nonfiction cross-reference
Alan Turing (1930s).
- Algorithm (nonfiction)
- Computational complexity (nonfiction)
- Computer science (nonfiction)
- Mathematics (nonfiction)
External links:
- Universal Turing machine @ Wikipedia