Analytic theory of crossed -modules and generalized numerical radius inequalities


Çetin S., GÜRDAL M., Gürdal U., Kittaneh F.

Journal of Analysis, cilt.34, sa.4, ss.2363-2385, 2026 (ESCI, Scopus)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 34 Sayı: 4
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1007/s41478-026-01089-7
  • Dergi Adı: Journal of Analysis
  • Derginin Tarandığı İndeksler: Emerging Sources Citation Index (ESCI), Scopus
  • Sayfa Sayıları: ss.2363-2385
  • Anahtar Kelimeler: -algebra, Crossed Hilbert space, Crossed module, Multiplier algebra, Numerical radius, Operator inequality
  • Süleyman Demirel Üniversitesi Adresli: Evet

Özet

This study establishes a rigorous bridge between the theory of crossed modules and functional analysis by extending homological structures to the setting of -algebras. We develop a well-defined framework for crossed modules of Banach and -algebras, utilizing the theory of bimultipliers and their isometric relationship with multiplier algebras to ensure analytic consistency. Central to our construction is the introduction of a novel class of multidimensional structures termed crossed Hilbert spaces. By leveraging bounded linear transformations on these spaces, we construct a categorical bridge between operator algebras and crossed modules. As a primary application, we derive significant generalizations of classical numerical radius inequalities. Our results provide a higher-dimensional perspective on the relationship between the numerical radius and the operator norm, extending fundamental inequalities of operator theory to a broader analytic context.