Kummer theory

E463784

Kummer theory is a branch of algebraic number theory that studies abelian extensions of fields, especially cyclotomic and radical extensions, using properties of roots of unity and ideal class groups.

All labels observed (5)

How this entity was disambiguated

Statements (49)

Predicate Object
instanceOf branch of algebraic number theory ⓘ
theory in field theory ⓘ
appliesTo global fields ⓘ
local fields ⓘ
number fields ⓘ
assumes base field contains enough roots of unity ⓘ
characterizes Galois group as subgroup of multiplicative group modulo n-th powers ⓘ
abelian extensions via n-th power classes ⓘ
describes structure of abelian extensions of prime power degree ⓘ
extends Gauss’s theory of quadratic residues ⓘ
focusesOn abelian extensions of exponent n ⓘ
formalism often expressed using Galois cohomology groups H^1 and H^2 ⓘ
generalizes classical theory of cyclotomic fields ⓘ
hasGeneralization Artin reciprocity ⓘ
Iwasawa theory ⓘ
Lubin–Tate theory ⓘ
hasVariant global Kummer theory ⓘ
local Kummer theory ⓘ
historicalContext developed in the 19th century ⓘ
influenced development of class field theory ⓘ
development of ideal theory ⓘ
isPartOf abelian extension theory ⓘ
algebraic number theory ⓘ
namedAfter Ernst Kummer ⓘ
linked to: Ernst Eduard Kummer
originallyMotivatedBy study of Fermat's Last Theorem ⓘ
study of cyclotomic fields ⓘ
prefigures global class field theory ⓘ
relatedConcept Kummer character ⓘ
Kummer extension ⓘ
linked to: Kummer theory

Kummer radical ⓘ
Kummer surface (terminologically related but different area) ⓘ
relatesTo Galois cohomology ⓘ
Hilbert class field ⓘ
Kummer map ⓘ
Kummer pairing ⓘ
Kummer sequence ⓘ
class field theory ⓘ
ideal class group ⓘ
ray class group ⓘ
requires primitive n-th root of unity in the base field ⓘ
studies abelian extensions of fields ⓘ
cyclotomic extensions ⓘ
radical extensions ⓘ
typicalAssumption characteristic of the field does not divide n ⓘ
uses ideal class groups ⓘ
local–global principles ⓘ
multiplicative group of a field ⓘ
n-th power residue symbol ⓘ
roots of unity ⓘ

How these facts were elicited

Referenced by (15)

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

Ernst Eduard Kummer → knownFor → Kummer theory ⓘ
Ernst Eduard Kummer → knownFor → Kummer extensions ⓘ
linked to: Kummer theory
cyclotomic field → centralTo → Kummer theory ⓘ
subject linked to: cyclotomic fields
Gaussian periods → relatedTo → Kummer theory ⓘ
Cohomologie Galoisienne → topic → Kummer theory ⓘ
Ernst Eduard Kummer → notableFor → Kummer theory in algebraic number theory ⓘ
subject linked to: Kummer
linked to: Kummer theory
Ernst Eduard Kummer → notableFor → Kummer extensions ⓘ
subject linked to: Kummer
linked to: Kummer theory
Kummer → hasEponym → Kummer theory ⓘ
Kummer → hasEponym → Kummer extension ⓘ
linked to: Kummer theory
Kummer theory → relatedConcept → Kummer extension ⓘ
linked to: Kummer theory
Artin–Schreier theory → isAnalogousTo → Kummer theory for multiplicative extensions ⓘ
linked to: Kummer theory
Hilbert symbol → relatedTo → Kummer theory ⓘ
Galois cohomology → hasKeyConcept → Kummer theory ⓘ
Tate pairing → definedUsing → Kummer theory ⓘ
Cohomologie Galoisienne → relatedTo → Kummer theory ⓘ
subject linked to: CG