Results 1 to 10 of about 1,268 (93)
On partial isometries with circular numerical range
Concrete Operators, 2021 In their LAMA 2016 paper Gau, Wang and Wu conjectured that a partial isometry A acting on ℂn cannot have a circular numerical range with a non-zero center, and proved this conjecture for n ≤ 4. We prove it for operators with rank A = n − 1 and any n.
Wegert Elias, Spitkovsky Ilya
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Dynamical study of Lyapunov exponents for Hide’s coupled dynamo model
Demonstratio Mathematica, 2021 In this paper, we introduced the Lyapunov exponents (LEs) as a significant tool that is used to study the numerical solution behavior of the dynamical systems. Moreover, Hide’s coupled dynamo model presents a valuable dynamical study.
Alresheedi Teflah, Allahem Ali
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The Numerical Range of C*ψ Cφ and Cφ C*ψ
Concrete Operators, 2021 In this paper we investigate the numerical range of C*bφm Caφn and Caφn C*bφm on the Hardy space where φ is an inner function fixing the origin and a and b are points in the open unit disc.
Clifford John +2 more
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Further extensions of Hartfiel’s determinant inequality to multiple matrices
Special Matrices, 2021 Following the recent work of Zheng et al., in this paper, we first present a new extension Hartfiel’s determinant inequality to multiple positive definite matrices, and then we extend the result to a larger class of matrices, namely, matrices whose ...
Luo Wenhui
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On 3-by-3 row stochastic matrices
Special Matrices, 2023 The known constructive tests for the shapes of the numerical ranges in the 3-by-3 case are further specified when the matrices in question are row stochastic. Auxiliary results on the unitary (ir)reducibility of such matrices are also obtained.
Pham Nhi, Spitkovsky Ilya M.
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Inverse properties of a class of seven-diagonal (near) Toeplitz matrices
Special Matrices, 2021 This paper presents the explicit inverse of a class of seven-diagonal (near) Toeplitz matrices, which arises in the numerical solutions of nonlinear fourth-order differential equation with a finite difference method.
Kurmanbek Bakytzhan +2 more
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Some consequences of the rank normal form of a matrix
Acta Universitatis Sapientiae: Mathematica, 2019 If A is a rectangular matrix of rank r, then A may be written as PSQ where P and Q are invertible matrices and s=(IrOOO)s = \left( {\matrix{ \hfill {{{\rm{I}}_{\rm{r}}}} & \hfill {\rm{O}} \cr \hfill {\rm{O}} & \hfill {\rm{O}} \cr } } \right).
Rădulescu Sorin +2 more
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New versions of refinements and reverses of Young-type inequalities with the Kantorovich constant
Special Matrices, 2023 Recently, some Young-type inequalities have been promoted. The purpose of this article is to give further refinements and reverses to them with Kantorovich constants.
Rashid Mohammad H. M., Bani-Ahmad Feras
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Distributive and Dual Distributive Elements in Hyperlattices
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2017 In this paper we introduce and study distributive elements, dual distributive elements in hyperlattices, and prove that these elements forms ∧-semi lattice and ∨-semi hyperlattice, respectively.
Ameri Reza +3 more
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On some reciprocal matrices with elliptical components of their Kippenhahn curves
Special Matrices, 2021 By definition, reciprocal matrices are tridiagonal n-by-n matrices A with constant main diagonal and such that ai,i+1ai+1,i= 1 for i = 1, . . ., n − 1.
Jiang Muyan, Spitkovsky Ilya M.
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