Galois correspondence
E904574
Galois correspondence is a fundamental concept in field theory that establishes a one-to-one relationship between intermediate field extensions and subgroups of a Galois group.
Statements (47)
| Predicate | Object |
|---|---|
| instanceOf |
concept in Galois theory
ⓘ
concept in field theory ⓘ mathematical concept ⓘ |
| appliesTo | Galois extensions ⓘ |
| assumes | field extensions are over a fixed base field ⓘ |
| centralTo |
inverse Galois problem
ⓘ
modern algebraic number theory ⓘ theory of finite fields ⓘ |
| characterizes | Galois extensions by the existence of a lattice isomorphism ⓘ |
| direction |
larger subgroups correspond to smaller intermediate fields
ⓘ
smaller subgroups correspond to larger intermediate fields ⓘ |
| domain | finite Galois extensions ⓘ |
| field |
Galois theory
NERFINISHED
ⓘ
abstract algebra ⓘ field theory ⓘ |
| formalizedAs | anti-isomorphism of lattices ⓘ |
| generalizedTo |
Galois theory of infinite extensions via Krull topology
ⓘ
infinite Galois extensions ⓘ |
| hasAnalogue | Galois connection in order theory ⓘ |
| hasVariant |
Galois correspondence for covering spaces in algebraic topology
ⓘ
Galois correspondence in algebraic geometry NERFINISHED ⓘ fundamental theorem of Galois theory ⓘ |
| historicalContext | developed in the 19th century ⓘ |
| implies |
normal subgroups correspond to normal intermediate extensions in towers
ⓘ
quotient groups correspond to subextensions ⓘ |
| involves |
Galois group
ⓘ
automorphisms of a field extension ⓘ fixed field of a subgroup ⓘ |
| is | a one-to-one correspondence between intermediate fields and subgroups of the Galois group ⓘ |
| maps |
each intermediate field to its stabilizer subgroup in the Galois group
ⓘ
each subgroup of the Galois group to its fixed field ⓘ |
| namedAfter | Évariste Galois NERFINISHED ⓘ |
| property |
inclusion-reversing
ⓘ
order-reversing ⓘ |
| relates |
intermediate fields
ⓘ
subgroups of a Galois group ⓘ |
| requires |
Galois group acts faithfully on the extension field
ⓘ
normality of the extension ⓘ separability of the extension ⓘ |
| structure | lattice anti-isomorphism between intermediate fields and subgroups ⓘ |
| typicalCondition |
the base field is contained in every intermediate field
ⓘ
the extension field is fixed by the trivial subgroup only ⓘ |
| typicalStatement | there is a bijection between intermediate fields of a finite Galois extension and subgroups of its Galois group ⓘ |
| usedIn |
classification of field extensions
ⓘ
construction of splitting fields ⓘ solvability of polynomial equations by radicals ⓘ study of normal closures ⓘ |
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.
subject surface form:
Évariste Galois