Structure Theorem For Finitely Generated Modules Over A Principal Ideal Domain - Statement

Statement

When a vector space over a field F has a finite generating set, then one may extract from it a basis consisting of a finite number n of vectors, and the space is therefore isomorphic to Fn. The corresponding statement with the F generalized to a principal ideal domain R is no longer true, as a finitely generated module over R need not have any basis. However such a module is still isomorphic to a quotient of some module Rn with n finite (to see this it suffices to construct the morphism that sends the elements of the canonical basis Rn to the generators of the module, and take the quotient by its kernel.) By changing the choice of generating set, one can in fact describe the module as the quotient of some Rn by a particularly simple submodule, and this is the structure theorem.

The structure theorem for finitely generated modules over a principal ideal domain usually appears in the following two forms.

Read more about this topic:  Structure Theorem For Finitely Generated Modules Over A Principal Ideal Domain

Famous quotes containing the word statement:

    The force of truth that a statement imparts, then, its prominence among the hordes of recorded observations that I may optionally apply to my own life, depends, in addition to the sense that it is argumentatively defensible, on the sense that someone like me, and someone I like, whose voice is audible and who is at least notionally in the same room with me, does or can possibly hold it to be compellingly true.
    Nicholson Baker (b. 1957)

    He that writes to himself writes to an eternal public. That statement only is fit to be made public, which you have come at in attempting to satisfy your own curiosity.
    Ralph Waldo Emerson (1803–1882)

    Eroticism has its own moral justification because it says that pleasure is enough for me; it is a statement of the individual’s sovereignty.
    Mario Vargas Llosa (b. 1936)