Differential graded module

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Short description: Mathematical concept

In algebra, a differential graded module, or dg-module, is a [math]\displaystyle{ \mathbb{Z} }[/math]-graded module together with a differential; i.e., a square-zero graded endomorphism of the module of degree 1 or −1, depending on the convention. In other words, it is a chain complex having a structure of a module, while a differential graded algebra is a chain complex with a structure of an algebra.

In view of the module-variant of Dold–Kan correspondence, the notion of an [math]\displaystyle{ \mathbb{N}_0 }[/math]-graded dg-module is equivalent to that of a simplicial module; "equivalent" in the categorical sense; see § The Dold–Kan correspondence below.

The Dold–Kan correspondence

Given a commutative ring R, by definition, the category of simplicial modules are simplicial objects in the category of R-modules; denoted by sModR. Then sModR can be identified with the category of differential graded modules which vanish in negative degrees via the Dold-Kan correspondence.[1]

See also

References