Halting problem

E143342

The halting problem is a fundamental decision problem in computability theory that asks whether a given program will eventually stop running or continue to run forever, and is famously proven to be undecidable.

All labels observed (2)

Label Occurrences
Chaitin's constant 1
Halting problem canonical 1

How this entity was disambiguated

Statements (50)

Predicate Object
instanceOf decision problem
problem in computability theory
undecidable problem
appliesTo Turing-complete programming languages
abstract machine models equivalent to Turing machines
asks whether a given program halts on a given input
whether a given program runs forever on a given input
cannotBe decided by any single algorithm for all program–input pairs
concerns Turing machine
surface form: Turing machines

behavior of algorithms
doesNotApplyTo finite-state machines in the same way
field computability theory
mathematical logic
theoretical computer science
formalizedAs membership problem for the halting set K
set of indices of Turing machines that halt on a given input
hasComplexityClass not decidable in any classical time or space complexity class
hasConsequence no algorithm can detect all infinite loops
no perfect general-purpose program verifier exists
hasEncoding as a yes–no decision problem
hasNotation HALT
K
hasProperty undecidable
unsolvable by any general algorithm
hasVariant termination problem in program analysis
totality problem
implies existence of undecidable problems in arithmetic
limits of algorithmic computation
influenced development of program verification
philosophy of computation
theory of formal methods
introducedInWork On Computable Numbers with an Application to the Entscheidungsproblem
surface form: On Computable Numbers, with an Application to the Entscheidungsproblem
isCompleteFor recursively enumerable sets under many-one reduction
proofTechnique diagonalization
reduction ad absurdum
self-reference
proofYear 1936
provenBy Alan Turing
relatedTo Church–Turing thesis
Entscheidungsproblem
Gödel's incompleteness theorems
Rice's theorem
Turing degree of the halting set
computable functions
partial computable functions
solutionSet recursively enumerable but not recursive
solutionType no total computable function decides it
standardFormulation Given a description of a program and an input, decide whether the program eventually halts when run on that input
usedIn proofs of undecidability of other problems
reductions in computability theory

How these facts were elicited

Referenced by (2)

Full triples — surface form annotated when it differs from this entity's canonical label.

Church–Turing thesis relatesToConcept Halting problem
Kolmogorov complexity relatedTo Halting problem
this entity surface form: Chaitin's constant