Results 21 to 30 of about 456,012 (313)

Polynomials and Numerical Ranges [PDF]

Proceedings of the American Mathematical Society, 1988
Let A A be an n × n n \times n complex matrix. For 1 ≤ k ≤ n 1 \leq k \leq n we study the inclusion relation for the following polynomial sets related to the matrix A A . (a) The classical numerical range of the k
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Some results on Drazin-Dagger matrices, reciprocal matrices, and conjugate EP matrices [PDF]

Journal of Mahani Mathematical Research
In this paper, a class of matrices, namely, Drazin-dagger matrices, in which the Drazin inverse andthe Moore-Penrose inverse commute, is introduced. Also, some properties of the generalized inverses of these matrices, are investigated.
Mahdiyeh Mortezaei, Gholamreza Aghamollaei   +1 more
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Volterra operator norms : a brief survey

Moroccan Journal of Pure and Applied Analysis, 2023
In this expository article, we discuss the evaluation and estimation of the operator norms of various functions of the Volterra operator.
Ransford Thomas
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Numerical Range of Moore–Penrose Inverse Matrices

Mathematics, 2020
Let A be an n-by-n matrix. The numerical range of A is defined as W ( A ) = { x * A x : x ∈ C n , x * x = 1 } . The Moore–Penrose inverse A + of A is the unique matrix satisfying A A + A = A , A + A A + = A ...
Mao-Ting Chien
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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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Generalization of numerical range of polynomial operator matrices

Tikrit Journal of Pure Science, 2023
Suppose that  is a polynomial matrix operator where  for , are  complex matrix and let  be a complex variable. For an  Hermitian matrix , we define the -numerical range of polynomial matrix of  as , where .
Darawan Zrar Mohammed, Ahmed Muhammad
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Reduction of the c-numerical range to the classical numerical range

Linear Algebra and its Applications, 2011
For an \(n\)-by-\(n\) complex matrix \(A\) and a real \(n\)-tuple \(c=(c_1,\dots, c_n)\), the \(c\)-numerical range \(W_c(A)\) of \(A\) is, by definition, the subset \[ \Biggl\{\sum^n_{j=1} c_j x^*_j Ax_j: x_1,\dots, x_n\text{ form an orthonormal basis of }\mathbb{C}^n\Biggr\} \] of the complex plane.
Chien, Mao-Ting, Nakazato, Hiroshi
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Discontinuity of maximum entropy inference and quantum phase transitions

New Journal of Physics, 2015
In this paper, we discuss the connection between two genuinely quantum phenomena—the discontinuity of quantum maximum entropy inference and quantum phase transitions at zero temperature. It is shown that the discontinuity of the maximum entropy inference
Jianxin Chen, Zhengfeng Ji, Chi-Kwong Li, Yiu-Tung Poon, Yi Shen, Nengkun Yu, Bei Zeng, Duanlu Zhou   +7 more
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On the Numerical Range and Numerical Radius of the Volterra Operator

Известия Иркутского государственного университета: Серия "Математика", 2018
In this paper, we investigated the numerical range and the numerical radius of the classical Volterra operator on the complex space $L^2[0,1]$. In particular, we determined the numerical range, the numerical radius of real and imaginary part of the ...
L. Khadkhuu, D. Tsedenbayar
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Inverse Numerical Range and Determinantal Quartic Curves

Mathematics, 2020
A hyperbolic ternary form, according to the Helton–Vinnikov theorem, admits a determinantal representation of a linear symmetric matrix pencil. A kernel vector function of the linear symmetric matrix pencil is a solution to the inverse numerical range ...
Mao-Ting Chien, Hiroshi Nakazato
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