Projectivity and quasi-projectivity with respect to epimorphisms to simple modules


ALAGÖZ Y., Alizade R., Büyükaşlk E.

Journal of Algebra and its Applications, 2025 (SCI-Expanded, Scopus) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Basım Tarihi: 2025
  • Doi Numarası: 10.1142/s0219498825420071
  • Dergi Adı: Journal of Algebra and its Applications
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, MathSciNet, zbMATH
  • Anahtar Kelimeler: max-p-poor modules, max-projective modules, Simple-quasi-projective modules
  • Hatay Mustafa Kemal Üniversitesi Adresli: Evet

Özet

Using the notion of relative max-projectivity, max-projectivity domain of a module is investigated. Such a domain includes the class of all modules whose maximal submodules are direct summands (this class denoted as MDMod -R). We call a module max- p-poor if its max-projectivity domain is exactly the class MDMod -R. We establish the existence of max- p-poor modules over any ring. Furthermore, we study commutative rings whose simple modules are projective or max- p-poor. Additionally, we determine the right Noetherian rings for which all right modules are projective or p-poor. Max- p-poor abelian groups are fully characterized and shown to coincide precisely with p-poor abelian groups. We also further investigate modules that are max-projective relative to themselves, which are known as simple-quasi-projective modules. Several properties of these modules are provided, and the structure of certain classes of simple-quasi-projective modules is determined over specific commutative rings including the ring of integers and valuation domains.