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A category equivalence between homogeneous completely decomposable abelian groups and modules over principal ideal domains

✍ Scribed by Lutz Strüengmann


Publisher
Elsevier Science
Year
2001
Tongue
English
Weight
91 KB
Volume
159
Category
Article
ISSN
0022-4049

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✦ Synopsis


Let Z ⊆ R be a subgroup of the rationals and (S; ≤) a ÿnite poset. In this paper we introduce the category Rep(S; R) of homogeneous completely decomposable groups H of type R with distinguished homogeneous completely decomposable subgroups H i (i ∈ S) of the same type, respecting the order of S, i.e. if i; j ∈ S and i ≤ j, then H i ⊆ H j . We construct a category equivalence between the two categories Rep(S; R) and Rep(S; R0), where R0 =End(R). Using this equivalence we are able to obtain decomposition theorems for certain subclasses of Rep 2 (R) and Rep 3 (R). We prove that these special representations admit a decomposition into indecomposable representations of rank ≤ 2.