Abstract
Let A be a bounded linear operator defined on a complex Hilbert space and let
Also, we develop inequalities involving the numerical radius and the spectral radius for the sum of the product operators, from which we derive the inequalities
for all
Funding statement: Dr. Pintu Bhunia would like to thank SERB, Government of India for the financial support in the form of National Post Doctoral Fellowship (N-PDF, File No. PDF/2022/000325) under the mentorship of Professor Apoorva Khare.
References
[1] A. Abu-Omar, Spectral radius inequalities for sums of operators with an application to the problem of bounding the zeros of polynomials, Linear Algebra Appl. 550 (2018), 28–36. 10.1016/j.laa.2018.03.033Search in Google Scholar
[2] A. Abu-Omar and F. Kittaneh, Upper and lower bounds for the numerical radius with an application to involution operators, Rocky Mountain J. Math. 45 (2015), no. 4, 1055–1065. 10.1216/RMJ-2015-45-4-1055Search in Google Scholar
[3] P. Bhunia, S. Bag and K. Paul, Bounds for zeros of a polynomial using numerical radius of Hilbert space operators, Ann. Funct. Anal. 12 (2021), no. 2, Paper No. 21. 10.1007/s43034-020-00107-4Search in Google Scholar
[4] P. Bhunia, S. S. Dragomir, M. S. Moslehian and K. Paul, Lectures on Numerical Radius Inequalities, Infosys Sci. Found. Ser., Springer, Cham, 2022. 10.1007/978-3-031-13670-2Search in Google Scholar
[5] P. Bhunia, S. Jana, M. S. Moslehian and K. Paul, Improved inequalities for the numerical radius via Cartesian decomposition, Funct. Anal. Appl. (2023), 10.4213/faa3990. 10.4213/faa3990Search in Google Scholar
[6] P. Bhunia and K. Paul, Furtherance of numerical radius inequalities of Hilbert space operators, Arch. Math. (Basel) 117 (2021), no. 5, 537–546. 10.1007/s00013-021-01641-wSearch in Google Scholar
[7] P. Bhunia and K. Paul, New upper bounds for the numerical radius of Hilbert space operators, Bull. Sci. Math. 167 (2021), Paper No. 102959. 10.1016/j.bulsci.2021.102959Search in Google Scholar
[8] P. Bhunia and K. Paul, Proper improvement of well-known numerical radius inequalities and their applications, Results Math. 76 (2021), no. 4, Paper No. 177. 10.1007/s00025-021-01478-3Search in Google Scholar
[9] P. Bhunia and K. Paul, Annular bounds for the zeros of a polynomial from companion matrices, Adv. Oper. Theory 7 (2022), no. 1, Paper No. 8. 10.1007/s43036-021-00174-xSearch in Google Scholar
[10] M. L. Buzano, Generalizzazione della diseguaglianza di Cauchy–Schwarz, Rend. Semin. Mat. Univ. Politec. Torino 31 (1971/73), 405–409. Search in Google Scholar
[11] M. Fujii and F. Kubo, Operator norms as bounds for roots of algebraic equations, Proc. Japan Acad. 49 (1973), 805–808. 10.3792/pja/1195519149Search in Google Scholar
[12] M. Fujii and F. Kubo, Buzano’s inequality and bounds for roots of algebraic equations, Proc. Amer. Math. Soc. 117 (1993), no. 2, 359–361. 10.1090/S0002-9939-1993-1088441-XSearch in Google Scholar
[13] K. E. Gustafson and D. K. M. Rao, Numerical Range, Universitext, Springer, New York, 1997. 10.1007/978-1-4613-8498-4Search in Google Scholar
[14] R. A. Horn and C. R. Johnson, Matrix Analysis, Cambridge University, Cambridge, 1985. 10.1017/CBO9780511810817Search in Google Scholar
[15] T. Kato, Notes on some inequalities for linear operators, Math. Ann. 125 (1952), 208–212. 10.1007/BF01343117Search in Google Scholar
[16] F. Kittaneh, Notes on some inequalities for Hilbert space operators, Publ. Res. Inst. Math. Sci. 24 (1988), no. 2, 283–293. 10.2977/prims/1195175202Search in Google Scholar
[17] F. Kittaneh, Singular values of companion matrices and bounds on zeros of polynomials, SIAM J. Matrix Anal. Appl. 16 (1995), no. 1, 333–340. 10.1137/S0895479893260139Search in Google Scholar
[18] F. Kittaneh, Norm inequalities for sums of positive operators, J. Operator Theory 48 (2002), no. 1, 95–103. Search in Google Scholar
[19] F. Kittaneh, A numerical radius inequality and an estimate for the numerical radius of the Frobenius companion matrix, Studia Math. 158 (2003), no. 1, 11–17. 10.4064/sm158-1-2Search in Google Scholar
[20] F. Kittaneh, Bounds for the zeros of polynomials from matrix inequalities, Arch. Math. (Basel) 81 (2003), no. 5, 601–608. 10.1007/s00013-003-0525-6Search in Google Scholar
[21] F. Kittaneh, Numerical radius inequalities for Hilbert space operators, Studia Math. 168 (2005), no. 1, 73–80. 10.4064/sm168-1-5Search in Google Scholar
[22] F. Kittaneh, M. Odeh and K. Shebrawi, Bounds for the zeros of polynomials from compression matrix inequalities, Filomat 34 (2020), no. 3, 1035–1051. 10.2298/FIL2003035KSearch in Google Scholar
[23] H. Linden, Bounds for zeros of polynomials using traces and determinants, Seminarberichte Fachb. Math. FeU Hagen 69 (2000), 127–146. Search in Google Scholar
[24]
C. A. McCarthy,
[25] S. Sahoo and N. C. Rout, New upper bounds for the numerical radius of operators on Hilbert spaces, Adv. Oper. Theory 7 (2022), no. 4, Paper No. 50. 10.1007/s43036-022-00216-ySearch in Google Scholar
[26] S. Sahoo, N. C. Rout and M. Sababheh, Some extended numerical radius inequalities, Linear Multilinear Algebra 69 (2021), no. 5, 907–920. 10.1080/03081087.2019.1698510Search in Google Scholar
[27] Y. Seo, Numerical radius inequalities related to the geometric means of negative power, Oper. Matrices 13 (2019), no. 2, 489–493. 10.7153/oam-2019-13-37Search in Google Scholar
[28] A. Sheikhhosseini, M. Khosravi and M. Sababheh, The weighted numerical radius, Ann. Funct. Anal. 13 (2022), no. 1, Paper No. 3. 10.1007/s43034-021-00148-3Search in Google Scholar
[29] M. P. Vasić and D. J. Kečkić, Some inequalities for complex numbers, Math. Balkanica 1 (1971), 282–286. Search in Google Scholar
[30] P. Y. Wu and H.-L. Gau, Numerical Ranges of Hilbert Space Operators, Encyclopedia Math. Appl. 179, Cambridge University, Cambridge, 2021. Search in Google Scholar
© 2023 Walter de Gruyter GmbH, Berlin/Boston
Articles in the same Issue
- Frontmatter
- On the numerical solvability of the initial problem with weight for ordinary linear differential systems with singularities
- Multiplicative Lie-type derivations on standard operator algebras
- Numerical radius inequalities and estimation of zeros of polynomials
- Convolution equations on the Lie group G = (-1,1)
- Positive solutions for a fourth-order p-Laplacian boundary value problem
- Existence and asymptotic behavior of strictly convex solutions for singular k-Hessian equations with nonlinear gradient terms
- Characterization of Jordan two-sided centralizers and related maps on triangular rings
- Convergence and integrability of rational and double rational trigonometric series with coefficients of bounded variation of higher order
- Weak and strong type inequalities criteria for fractional maximal functions and fractional integrals associated with Gegenbauer differential operator
- Generating sets of F/R' Leibniz algebras
- New results of uncertain integrals and applications
- Multilinear commutators of multilinear strongly singular integral operators with generalized kernels
Articles in the same Issue
- Frontmatter
- On the numerical solvability of the initial problem with weight for ordinary linear differential systems with singularities
- Multiplicative Lie-type derivations on standard operator algebras
- Numerical radius inequalities and estimation of zeros of polynomials
- Convolution equations on the Lie group G = (-1,1)
- Positive solutions for a fourth-order p-Laplacian boundary value problem
- Existence and asymptotic behavior of strictly convex solutions for singular k-Hessian equations with nonlinear gradient terms
- Characterization of Jordan two-sided centralizers and related maps on triangular rings
- Convergence and integrability of rational and double rational trigonometric series with coefficients of bounded variation of higher order
- Weak and strong type inequalities criteria for fractional maximal functions and fractional integrals associated with Gegenbauer differential operator
- Generating sets of F/R' Leibniz algebras
- New results of uncertain integrals and applications
- Multilinear commutators of multilinear strongly singular integral operators with generalized kernels