Turing degrees

E679185

Turing degrees are an abstract classification of sets of natural numbers or decision problems according to their relative level of algorithmic unsolvability or computational complexity under Turing reducibility.

All labels observed (2)

Label Occurrences
Turing degrees canonical 3
Turing degree 1

How this entity was disambiguated

Statements (50)

Predicate Object
instanceOf equivalence classes under Turing reducibility ⓘ
mathematical concept ⓘ
structure in computability theory ⓘ
basedOn Turing reducibility ⓘ
captures relative algorithmic unsolvability ⓘ
relative computational complexity ⓘ
connectedTo effective descriptive set theory ⓘ
set of reals under Turing reducibility ⓘ
definedOn decision problems ⓘ
sets of natural numbers ⓘ
equivalenceClassOf sets of natural numbers mutually Turing reducible to each other ⓘ
equivalenceRelation mutual Turing reducibility ⓘ
field computability theory ⓘ
mathematical logic ⓘ
recursion theory ⓘ
formalizedIn second-order arithmetic ⓘ
hasBottomElement degree of computable sets ⓘ
hasOpenProblems automorphism group of the Turing degrees ⓘ
exact lattice-theoretic properties of the degrees ⓘ
hasOperation join ⓘ
hasProperty contains high and low degrees ⓘ
contains incomparable degrees ⓘ
contains minimal degrees ⓘ
every nonzero degree bounds a minimal degree ⓘ
not a lattice under Turing reducibility ⓘ
uncountable set of degrees ⓘ
hasStructure upper semilattice ⓘ
hasTopElement degree of the halting problem ⓘ
introducedInField mid 20th century computability theory ⓘ
namedAfter Alan Turing ⓘ
orderType partial order under Turing reducibility ⓘ
relatedTo Medvedev degrees ⓘ
Muchnik degrees ⓘ
Turing jump ⓘ
arithmetical hierarchy ⓘ
linked to: Kleene hierarchy

degrees of unsolvability ⓘ
hyperarithmetical hierarchy ⓘ
many-one degrees ⓘ
truth-table degrees ⓘ
studiedBy Alan Turing ⓘ
Emil Post ⓘ
Lachlan ⓘ
Sacks ⓘ
Shore ⓘ
Slaman ⓘ
Stephen Kleene ⓘ
symbol D_T ⓘ
usedFor analyzing the structure of unsolvable problems ⓘ
classifying decision problems by relative computability ⓘ
studying relative computability of real numbers ⓘ

How these facts were elicited

Referenced by (4)

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

Computability Theory → fieldOfStudy → Turing degrees ⓘ
Kleene hierarchy → relatedTo → Turing degrees ⓘ
Turing reducibility → relatedConcept → Turing degree ⓘ
linked to: Turing degrees