Disjoint Union

In mathematics, the term disjoint union may refer to one of two different but related concepts:

  • In set theory, the disjoint union (or discriminated union) of a family of sets is a modified union operation that indexes the elements according to which set they originated in; disjoint sets have no element in common.
  • When one says that a set is the disjoint union of a family of subsets, this means that it is the union of the subsets and that the subsets are pairwise disjoint.

Read more about Disjoint Union:  Set Theory Definition, Category Theory Point of View

Famous quotes containing the word union:

    How can I explain the difference to me between America and Russia?... the America I’ve known is a place where men on horseback escort union marchers, the Russia I’ve known is a place where men on horseback slaughter young Socialists and Jews.
    Golda Meir (1898–1978)