About the decomposability of almost completely decomposable groups

Budak, Canan
Almost completely decomposable groups are extensions of completely decomposable groups of finite index. They can be written as a sum of indecomposables. Every almost completely decomposable group is the direct sum of indecomposables but this decomposition is quite complicated and not unique. Almost completely decomposable groups can be represented by matrices, called coordinate matrices. If the coordinate matrix of a given almost completely decomposable group is decomposable then the group is decomposable. Under some restrictions, for example considering a weakening of isomorphism, called near-isomorphism some spacial classes of almost completely decomposable groups can be classified.


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Citation Formats
C. Budak, “About the decomposability of almost completely decomposable groups,” M.S. - Master of Science, Middle East Technical University, 2020.