Geodesic
Boundary Points of the Numerical Range of an Operator
Canadian mathematical bulletin, Tome 17 (1975) no. 5, pp. 689-692

Voir la notice de l'article provenant de la source Cambridge University Press

The purpose of this note is to investigate boundary points of the numerical range of an operator in terms of inner and outer center points. Some applications on commutators are given.Throughout this note, an operator will always mean a bounded linear operator on a Hilbert space X. 
Lin, C.-S. Boundary Points of the Numerical Range of an Operator. Canadian mathematical bulletin, Tome 17 (1975) no. 5, pp. 689-692. doi: 10.4153/CMB-1974-125-5
@article{10_4153_CMB_1974_125_5,
     author = {Lin, C.-S.},
     title = {Boundary {Points} of the {Numerical} {Range} of an {Operator}},
     journal = {Canadian mathematical bulletin},
     pages = {689--692},
     year = {1975},
     volume = {17},
     number = {5},
     doi = {10.4153/CMB-1974-125-5},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CMB-1974-125-5/}
}
TY  - JOUR
AU  - Lin, C.-S.
TI  - Boundary Points of the Numerical Range of an Operator
JO  - Canadian mathematical bulletin
PY  - 1975
SP  - 689
EP  - 692
VL  - 17
IS  - 5
UR  - http://geodesic.mathdoc.fr/articles/10.4153/CMB-1974-125-5/
DO  - 10.4153/CMB-1974-125-5
ID  - 10_4153_CMB_1974_125_5
ER  - 
%0 Journal Article
%A Lin, C.-S.
%T Boundary Points of the Numerical Range of an Operator
%J Canadian mathematical bulletin
%D 1975
%P 689-692
%V 17
%N 5
%U http://geodesic.mathdoc.fr/articles/10.4153/CMB-1974-125-5/
%R 10.4153/CMB-1974-125-5
%F 10_4153_CMB_1974_125_5

[1] 1. Berberian, S. K., Approximate proper vectors, Proc. Amer. Math. Soc. 13 (1962) 111–114. Google Scholar

[2] 2. Berberian, S. K. and Orland, G. H., On the closure of the numerical range of an operator, Proc. Amer. Math. Soc. 18 (1967) 499–503. Google Scholar

[3] 3. Halmos, P. R., A Hilbert Space Problem Book, Van Nostrand, Princeton (1967). Google Scholar

[4] 4. Hildebrandt, S., Über den numerischen Wertebereich eines Operators, Math. Ann. 163 (1966) 230–247. Google Scholar

[5] 5. Istrăţescu, V. and Istrăţescu, I., On bare and semibare points for some classes of operators, Portugal. Math. 29 (1970) 205–211. Google Scholar

[6] 6. Meng, Ching-Hwa, A condition that a normal operator have a closed numerical range, Proc. Amer. Math. Soc. 8 (1957) 85–88. Google Scholar

[7] 7. Orland, G. H., On a class of operators, Proc. Amer. Math. Soc. 15 (1964) 75–79. Google Scholar

[8] 8. Stampfli, J. G., Hyponormal operators and spectral density, Trans. Amer. Math. Soc. 117 (1965) 469–476. Google Scholar

[9] 9. Stampfli, J. G., Extreme points of the numerical range of a hyponormal operator, Michigan Math. J. 13 (1966) 87–89. Google Scholar

[10] 10. Stampfli, J. G., On hyponormal and Toeplitz operators, Math. Ann. 183 (1969) 328–336. Google Scholar

Cité par Sources :