Class Field Theory

This group gathers theorems from class field theory, the branch of algebraic number theory that describes the abelian extensions of a number field in terms of data intrinsic to the field itself, together with its Langlands-program descendants. It covers the Kronecker-Weber and Artin reciprocity theorems that found the pattern, the Takagi existence theorem and Chebotarev density theorem that make it precise, and later refinements involving Iwasawa theory, class number formulas, and automorphic representations that extend the same circle of ideas.