Galois cohomology
E839567
Galois cohomology is a branch of mathematics that studies Galois groups and their actions on modules using cohomological methods, providing powerful tools for understanding field extensions, algebraic number theory, and arithmetic geometry.
Statements (60)
| Predicate | Object |
|---|---|
| instanceOf |
branch of mathematics
ⓘ
cohomology theory ⓘ |
| appliesTo |
absolute Galois groups
ⓘ
algebraic extensions of fields ⓘ algebraic number fields ⓘ field extensions ⓘ global fields ⓘ local fields ⓘ |
| field |
algebra
ⓘ
arithmetic geometry ⓘ number theory ⓘ |
| formalDefinition | right derived functors of the fixed-point functor for Galois modules ⓘ |
| hasCanonicalReference | Serre: Galois Cohomology NERFINISHED ⓘ |
| hasHistoricalDevelopmentBy |
Chevalley
NERFINISHED
ⓘ
Serre NERFINISHED ⓘ Tate NERFINISHED ⓘ |
| hasKeyConcept |
Brauer group
NERFINISHED
ⓘ
Galois module ⓘ Hilbert 90 NERFINISHED ⓘ Hochschild–Serre spectral sequence NERFINISHED ⓘ Kummer theory NERFINISHED ⓘ Poitou–Tate duality NERFINISHED ⓘ Shapiro lemma NERFINISHED ⓘ Tate cohomology NERFINISHED ⓘ Tate–Shafarevich group NERFINISHED ⓘ cohomological dimension of a field ⓘ cohomology group H^n(G,M) ⓘ continuous cochains ⓘ corestriction map ⓘ cup product ⓘ fundamental class in H^2 ⓘ inflation–restriction sequence ⓘ local Tate duality NERFINISHED ⓘ norm map ⓘ profinite Galois group ⓘ restriction map ⓘ |
| relatedTo |
Galois representations
NERFINISHED
ⓘ
K-theory of fields NERFINISHED ⓘ Selmer group NERFINISHED ⓘ Weil group NERFINISHED ⓘ class field theory ⓘ motivic cohomology ⓘ étale cohomology ⓘ |
| studies |
Galois groups
ⓘ
actions of Galois groups on modules ⓘ continuous group cohomology of Galois groups ⓘ |
| typicalGroup | absolute Galois group of a field ⓘ |
| typicalModule |
discrete Galois module
GENERATED
ⓘ
finite Galois module GENERATED ⓘ p-adic Galois representation GENERATED ⓘ |
| usedIn |
classification of central simple algebras
ⓘ
description of the Brauer group of a field ⓘ obstructions to local-global principles ⓘ study of principal homogeneous spaces ⓘ study of rational points on varieties ⓘ study of torsors under algebraic groups ⓘ |
| usesMethod |
Ext functors
ⓘ
derived functors ⓘ group cohomology ⓘ homological algebra ⓘ |
Referenced by (5)
Full triples — surface form annotated when it differs from this entity's canonical label.
subject surface form:
Évariste Galois