TY  - JOUR
T1  - General Upper Bounds for the Numerical Radii of Powers of Hilbert Space Operators
AU  - Al-dolat, Mohammed
PY  - 2023
DA  - September
DO  - 10.55549/epstem.1334983
JF  - The Eurasia Proceedings of Science Technology Engineering and Mathematics
JO  - EPSTEM
PB  - ISRES Publishing
WT  - DergiPark
SN  - 2602-3199
SP  - 15
EP  - 25
VL  - 22
LA  - en
AB  - In this paper, we will present several upper bounds for the numerical radii of a operator matrices. We use these bounds to generalize and improve some well-known numerical radius inequalities. We provide a refinement of an earlier numerical radius inequality due to (Bani-Domi & Kittaneh, 2021) [Norm and numerical radius inequalities for Hilbert space operators], (Bani-Domi & Kittaneh, 2021) [Refined and generalized numerical radius inequalities for operator matrices] and (Al-Dolat & Kittaneh, 2023) [Upper bounds for the numerical radii of powers of Hilbert space operators].
KW  - Numerical radius
KW  - Usual operator norm
KW  - Operator matrix
KW  - Buzano inequality.
CR  - Abu-Omar, A. & Kittaneh, F. (2015). Upper and lower bounds for the numerical radius with an application to involution operators, Rocky Mountain Journal Math., 45(4), 1055-1065.
CR  - Al-Dolat, M., & Al-Zoubi, K. (2023). Improved and refined numerical radius inequalities for Hilbert space operators.https://assets.researchsquare.com/files/rs2668438/v1/a5b67b067e6f6fddcf09cb22.pdf?c=1678771282
CR  - Al-Dolat, M., Al-Zoubi, K., Ali, M., & Bani-Ahamed, F. (2016). General numerical radius inequalities for matrices of operators, Open Math., 4, 1-9.
CR  - Al-Dolat, M., & Jaradat, I. (2023). A refinement of the Cauchy-Shwarz inequality accompanied by new numerical radius upper bounds. Filomat, 37, 971-977.
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UR  - https://doi.org/10.55549/epstem.1334983
L1  - https://dergipark.org.tr/en/download/article-file/3296580
ER  -