CatDat

category of graded modules over a graded ring

Here, GG is a monoid (written additively), R=(Rn)nGR = (R_n)_{n \in G} is a non-trivial GG-graded ring, and we consider GG-graded RR-modules, consisting of abelian groups (Mn)nG(M_n)_{n \in G} and bilinear maps Rn×MmMn+mR_n \times M_m \to M_{n+m} satisfying the module axioms. Typical examples are G=NG = \IN and G=ZG = \IZ, both with respect to addition.

Satisfied Properties

Assigned properties

Deduced properties

Unsatisfied Properties

Assigned properties

Deduced properties*

*This also uses the deduced satisfied properties.

Unknown properties

Undecidable properties

There are 2 properties for which it cannot be decided if they are satisfied or not.

Special objects

  • terminal object: the zero graded module with 0n00_n \coloneqq 0
  • initial object: the zero graded module with 0n00_n \coloneqq 0
  • products: degree-wise defined direct products
  • coproducts: degree-wise defined direct sums

Special morphisms

  • isomorphisms: morphisms that are bijective in each degree
  • monomorphisms: morphisms that are injective in each degree
  • epimorphisms: morphisms that are surjective in each degree
  • regular monomorphisms: same as monomorphisms
  • regular epimorphisms: same as epimorphisms