On the Pseudospectra of q-Quasinormal Operators
International Conference on Approximation Theory and Special Functions (ATSF 2026 – 9th Series), Ankara, Türkiye, 2 - 05 Eylül 2026, ss.49, (Özet Bildiri)
- Yayın Türü: Bildiri / Özet Bildiri
- Basıldığı Şehir: Ankara
- Basıldığı Ülke: Türkiye
- Sayfa Sayıları: ss.49
- Açık Arşiv Koleksiyonu: AVESİS Açık Erişim Koleksiyonu
- Karadeniz Teknik Üniversitesi Adresli: Evet
Özet
This study investigates the ε-pseudospectra of bounded q-quasinormal operators acting on separable Hilbert spaces, where q > 1. By using the structural representation of such operators as weighted shift-type tensor product operators, several geometric properties of their pseudospectra are obtained. It is also shown that, as q → ∞, the pseudospectra of these operators approach the pseudospectrum of a rank-one nilpotent operator. This shows that the limiting behavior is determined mainly by the nonnormal structure of the operator rather than by its spectrum.