Inequalities for the numerical radius in unital normed algebras

• Autorzy: Dragomir S.
• Języki publikacji: EN

Abstrakty

EN

In this paper, some inequalities between the numerical radius of an element from a unital normed algebra and certain semi-inner products involving that element and the unity are given.

Słowa kluczowe

EN

unital normed algebras; numerical radius

PL

algebra unitarna; promienie

• Wydawca: De Gruyter
• Czasopismo: Demonstratio Mathematica
• Rocznik: 2010
• Tom: Vol. 43, nr 1
• Strony: 129--137
• Opis fizyczny: Bibliogr. 6 poz.

Twórcy

autor

Dragomir S.

• Mathematics, School of Engineering & Science Victoria University PO Box 14428, Melbourne Victoria, 8001, Australia,

Bibliografia

• [1] H. F. Bohnenblust, S. Karlin, Geometrical properties of the unit sphere of Banach algebras, Ann. of Math. 62 (1955), 217-229
• [2] F. F. Bonsall, J. Duncan, Numerical Ranges of Operators on Normed Spaces and of Elements of Normed Algebras, Cambridge University Press, 1971.
• [3] M. J. Crabb, Numerical range estimates for the norm of iterated operators, Glasgow Math. J. 11 (1970), 85-87.
• [4] S. S. Dragomir, Semi-inner Products and Applications. Nova Science Publishers, Inc., Hauppauge, NY, 2004. x+222 pp.
• [5] G. Lumer, Semi-inner product spaces, Trans. Amer. Math. Soc. 100 (1961), 29-43.
• [6] B. W. Glickfeld, On an inequality of Banach algebra geometry and semi-inner product space theory, Illinois J. Math. 14 (1970), 76-81.