Ideal Class Group

Ideal Class Group

In mathematics, the extent to which unique factorization fails in the ring of integers of an algebraic number field (or more generally any Dedekind domain) can be described by a certain group known as an ideal class group (or class group). If this group is finite (as it is in the case of the ring of integers of a number field), then the order of the group is called the class number. The multiplicative theory of a Dedekind domain is intimately tied to the structure of its class group. For example, the class group of a Dedekind domain is trivial if and only if the ring is a unique factorization domain.

Read more about Ideal Class Group:  History and Origin of The Ideal Class Group, Definition, Properties, Relation With The Group of Units, Examples of Ideal Class Groups, Connections To Class Field Theory

Famous quotes containing the words ideal, class and/or group:

    “The ideal college is Mark Hopkins on one end of a log and a student on the other.”
    —James A. Garfield (1831–1881)

    “Each class of society has its own requirements; but it may be said that every class teaches the one immediately below it; and if the highest class be ignorant, uneducated, loving display, luxuriousness, and idle, the same spirit will prevail in humbler life.”
    —First published in Girls’ Home Companion (1895)

    “No other group in America has so had their identity socialized out of existence as have black women.... When black people are talked about the focus tends to be on black men; and when women are talked about the focus tends to be on white women.”
    —bell hooks (b. c. 1955)