Algebraic Structures in Cat<SUP>1</SUP>-Groups: Normality, Quotients, Coverings, and Actions via Crossed Modules


TEMEL S.

JOURNAL OF MATHEMATICS, cilt.2026, sa.1, 2026 (SCI-Expanded)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 2026 Sayı: 1
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1155/jom/5519446
  • Dergi Adı: JOURNAL OF MATHEMATICS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED)
  • Recep Tayyip Erdoğan Üniversitesi Adresli: Evet

Özet

This paper develops a systematic framework for coverings, actions, and quotient structures in cat(1)-groups. While cat(1)-groups are categorically equivalent to crossed modules and 2-groups, their explicit treatment via defining maps has remained limited. We introduce coverings and actions directly within the cat(1)-group structure and establish categorical equivalences between coverings, actions, and liftings of crossed modules. Constructive definitions of normal subcat(1)-groups and quotient cat(1)-groups are provided by translating properties of normal subcrossed modules through the equivalence functor. Our aim is to present a coherent algebraic framework that connects quotient structures of cat(1)-groups to coverings and crossed modules, thereby filling a gap in the literature and offering new tools for homological algebra and exact sequences. In particular, we show that the quotient structure of a cat(1)-group simultaneously generates its covering morphism and aligns with lifting constructions of crossed modules.