In mathematics, a Galois module is a G-module, with G being the Galois group of some extension of fields. The term Galois representation is frequently used when the G-module is a vector space over a field or a free module over a ring in representation theory, but can also be used as a synonym for G-module. The study of Galois modules for extensions of local or global fields and their group cohomology is an important tool in number theory.
In mathematics, a Galoismodule is a G-module, with G being the Galois group of some extension of fields. The term Galois representation is frequently...
theory. More generally one can define the Selmer group of a finite Galoismodule M (such as the kernel of an isogeny) as the elements of H1(GK,M) that...
arithmetic interest over infinite towers of number fields. It began as a Galoismodule theory of ideal class groups, initiated by Kenkichi Iwasawa (1959) (岩澤...
can never form a Z-module basis of Z[i] because 1 cannot be an integer combination. The reasons are studied in depth in Galoismodule theory. The regular...
normal integral basis is part of Galoismodule theory. Let F ⊂ K {\displaystyle F\subset K} be a Galois extension with Galois group G {\displaystyle G} . The...
mathematics, Galois cohomology is the study of the group cohomology of Galoismodules, that is, the application of homological algebra to modules for Galois groups...
situations, the Galois group acts on other mathematical objects, for example a group. Such a group is then also referred to as a Galoismodule. This enables...
G are an abelian group. The p-adic Tate module Tp(G) of G is a Galois representation (of the absolute Galois group, GK, of K). Classical results on abelian...
In Galois cohomology, local Tate duality (or simply local duality) is a duality for Galoismodules for the absolute Galois group of a non-archimedean...
of the Milnor K-group of a field k with the Galois cohomology of k with coefficients in the Galoismodule of ℓth roots of unity. The point of the conjecture...
action of the absolute Galois group of K. Given a finite separable field extension L/K and a torus T over L, we have a Galoismodule isomorphism X ∙ ( R...
of extensions is known better when L/K is Galois. Let (K, v) be a valued field and let L be a finite Galois extension of K. Let Sv be the set of equivalence...
Frobenius reciprocity. Galois A Galoismodule is a module over the group ring of a Galois group. generating set A subset of a module is called a generating...
algebraic group Global field Hasse principle Hasse–Minkowski theorem GaloismoduleGalois cohomology Brauer group Class field theory Abelian extension Kronecker–Weber...
field theory. Unlike the classical case, Milnor K-groups do not satisfy Galoismodule descent if n > 1 {\displaystyle n>1} . General higher-dimensional local...
In mathematics, a finite field or Galois field (so-named in honor of Évariste Galois) is a field that contains a finite number of elements. As with any...
created by Kenkichi Iwasawa, Iwasawa theory was originally developed as a Galoismodule theory of ideal class groups. The main conjecture of Iwasawa theory...
this goal when K is an abelian extension of Q (that is, a Galois extension with abelian Galois group). Unique factorization fails if and only if there are...