dist-FORMULAS AND TOEPLITZ OPERATORS
ANNALS OF FUNCTIONAL ANALYSIS, cilt.6, sa.1, ss.221-226, 2015 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 6 Sayı: 1
- Basım Tarihi: 2015
- Doi Numarası: 10.15352/afa/06-1-16
- Dergi Adı: ANNALS OF FUNCTIONAL ANALYSIS
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Sayfa Sayıları: ss.221-226
- Süleyman Demirel Üniversitesi Adresli: Evet
Özet
The distance from the nonconstant function phi in L-infinity(T) to the set F-const of all constant functions is estimated in terms of Hankel operators on the Hardy space H-2(D) over the unit disk D = {z is an element of C : \z\ < 1}. We give a sufficient condition ensuring the equality dist(phi, F-const) = ||phi||(L infinity). Some other dist-formulas are also discussed.