Difference between revisions of "Entscheidungsproblem"
Karl Jones (Talk | contribs) (→External links) |
Karl Jones (Talk | contribs) (→See also) |
||
| Line 14: | Line 14: | ||
* [[Algorithm]] | * [[Algorithm]] | ||
| − | * [[Alonzo Church | + | * [[Alonzo Church]] |
* [[Lambda calculus]] | * [[Lambda calculus]] | ||
| − | * [[Alan Turing | + | * [[Alan Turing]] |
* [[Turing machine]] | * [[Turing machine]] | ||
* [[Undecidable problem]] | * [[Undecidable problem]] | ||
Revision as of 12:44, 24 April 2016
In mathematics and computer science, the Entscheidungsproblem (pronounced [ɛntˈʃaɪ̯dʊŋspʁoˌbleːm], German for 'decision problem') is a challenge posed by David Hilbert in 1928.
Description
The Entscheidungsproblem asks for an algorithm that takes as input a statement of a first-order logic (possibly with a finite number of axioms beyond the usual axioms of first-order logic) and answers "Yes" or "No" according to whether the statement is universally valid, i.e., valid in every structure satisfying the axioms.
By the completeness theorem of first-order logic, a statement is universally valid if and only if it can be deduced from the axioms, so the Entscheidungsproblem can also be viewed as asking for an algorithm to decide whether a given statement is provable from the axioms using the rules of logic.
In 1936, Alonzo Church and Alan Turing published independent papers showing that a general solution to the Entscheidungsproblem is impossible, assuming that the intuitive notion of "effectively calculable" is captured by the functions computable by a Turing machine (or equivalently, by those expressible in the lambda calculus).
This assumption is now known as the Church–Turing thesis.
See also
External links
- Entscheidungsproblem @ Wikipedia
