In mathematics, specifically module theory, given a ring R and R-modules
,the module E is an essential extension if for every nonzero submodule
,we have
. Mathematics is the body of Knowledge and Academic discipline that studies such concepts as Quantity, Structure, Space and In Abstract algebra, the concept of a module over a ring is a generalization of the notion of Vector space, where instead of requiring the scalars In Mathematics, a ring is an Algebraic structure which generalizes the algebraic properties of the Integers though the rational, real In Abstract algebra, the concept of a module over a ring is a generalization of the notion of Vector space, where instead of requiring the scalars Also, M is then said to be an essential submodule of E.
Some key properties are that given
,there exists a maximal submodule

containing M with respect to the property of being an essential extension of M. Given such modules, F being injective implies that E is injective. In Mathematics, especially in the area of Abstract algebra known as Module theory, an injective module is a module Q that shares certain Finally, given any module M, there is an essential extension E of M that is an injective module, and E is unique up to isomorphism. In Abstract algebra, an isomorphism ( Greek: ἴσος isos "equal" and μορφή morphe "shape" is a bijective Such a module E is called the injective envelope of M. In Mathematics, especially in the area of Abstract algebra known as Module theory, the injective hull (or injective envelope) of a module is