Algebraic entropies, Hopficity and co-Hopficity of direct sums of Abelian Groups

• Autorzy: Brendan Goldsmith , Ketao Gong
• Języki publikacji: EN

Abstrakty

EN

Necessary and sufficient conditions to ensure that the direct sum of two Abelian groups with zero entropy is again of zero entropy are still unknown; interestingly the same problem is also unresolved for direct sums of Hopfian and co-Hopfian groups.We obtain sufficient conditions in some situations by placing restrictions on the homomorphisms between the groups. There are clear similarities between the various cases but there is not a simple duality involved.

Słowa kluczowe

EN

algebraic entropy; adjoint entropy; direct sums; matrix of endomorphisms; Abelian groups

• Wydawca: De Gruyter Open
• Czasopismo: Topological Algebra and its Applications
• Rocznik: 2015
• Tom: 3
• Numer: 1

Daty

otrzymano

2015-08-07

zaakceptowano

2015-08-13

online

2015-11-09

Twórcy

autor

Brendan Goldsmith

• School of Mathematical Sciences, Dublin Institute of Technology, Aungier Street, Dublin 8, Ireland

autor

Ketao Gong

• School of Mathematics and Statistics, Hubei Engineering University, No. 272, Jiaotong
  Road, Xiaogan City, Hubei Province, 432000, P.R.China

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Identyfikatory

DOI

10.1515/taa-2015-0007