Decomposition of graded modules
Author:
Cary Webb
Journal:
Proc. Amer. Math. Soc. 94 (1985), 565-571
MSC:
Primary 13C05
DOI:
https://doi.org/10.1090/S0002-9939-1985-0792261-6
MathSciNet review:
792261
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Abstract | References | Similar Articles | Additional Information
Abstract: In this paper, the primary objective is to obtain decomposition theorems for graded modules over the polynomial ring $k[x]$, where $k$ denotes a field. There is some overlap with recent work of Höppner and Lenzing. The results obtained include identification of the free, projective, and injective modules. It is proved that a module that is either reduced and locally finite or bounded below is a direct sum of cyclic submodules. Pure submodules are direct summands if they are bounded below. In such case, the pure submodule is itself a direct sum of cyclic submodules. It is also noted that Cohen and Gluck’s Stacked Bases Theorem remains true if the modules are graded.
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Keywords:
Graded module,
direct sum,
pure submodule
Article copyright:
© Copyright 1985
American Mathematical Society