Refined q-Berezin Radius Inequalities for Operators and 2×2 Block Matrices


GÜRDAL M., Kittaneh F., Stojiljković V.

Complex Analysis and Operator Theory, cilt.20, sa.4, 2026 (SCI-Expanded, Scopus)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 20 Sayı: 4
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1007/s11785-026-01951-3
  • Dergi Adı: Complex Analysis and Operator Theory
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, MathSciNet, zbMATH
  • Anahtar Kelimeler: Berezin norm, Berezin number, Operator matrix inequality, q-Berezin radius, Reproducing kernel Hilbert space
  • Süleyman Demirel Üniversitesi Adresli: Evet

Özet

In this paper, we establish upper bounds for the q-Berezin radii of bounded linear operators acting on reproducing kernel Hilbert spaces. Specifically, we derive inequalities for the sum X+Y and product Y∗X of operators utilizing the Berezin norms of operator powers and integral refinements of the Cauchy-Schwarz inequality. We further provide explicit estimates for the q-Berezin radii of 2×2 block operator matrices bounding the off-diagonal terms in relation to the diagonal entries. The obtained results recover the standard Berezin number inequalities when q=1 and provide stronger estimates than the existing upper bounds for the general q-numerical radius.