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We consider the problem of determining which matrices are permutable to be supmodular. We show that for small dimensions any matrix is permutable by a universal permutation or by a pair of permutations, while for higher dimensions no…

Combinatorics · Mathematics 2024-09-13 Shmuel Onn

Given an integral domain A we consider the set of all integral elements over A that can occur as an eigenvalue of a symmetric matrix over A. We give a sufficient criterion for being such an element. In the case where A is the ring of…

Number Theory · Mathematics 2016-08-12 Mario Kummer

Dual complex matrices have found applications in brain science. There are two different definitions of the dual complex number multiplication. One is noncommutative. Another is commutative. In this paper, we use the commutative definition.…

Rings and Algebras · Mathematics 2023-06-26 Liqun Qi , Chunfeng Cui

Eigenvalues of a density matrix characterize well the quantum state's properties, such as coherence and entanglement. We propose a simple method to determine all the eigenvalues of an unknown density matrix of a finite-dimensional system in…

Quantum Physics · Physics 2014-01-24 Tohru Tanaka , Yukihiro Ota , Mitsunori Kanazawa , Gen Kimura , Hiromichi Nakazato , Franco Nori

We characterize the relationship between the singular values of a complex Hermitian (resp., real symmetric, complex symmetric) matrix and the singular values of its off-diagonal block. We also characterize the eigenvalues of an Hermitian…

Algebraic Geometry · Mathematics 2007-05-23 Sergey Fomin , William Fulton , Chi-Kwong Li , Yiu-Tung Poon

The concepts of differentiation and integration for matrices are known. As far as each matrix is differentiable, it is not clear a priori whether a given matrix is integrable or not. Recently some progress was obtained for diagonalizable…

Combinatorics · Mathematics 2023-09-08 Suren Danielyan , Alexander Guterman , Elena Kreines , Fedor Pakovich

In this note we describe the limit and the extended limit sets of every vector for a single matrix in Jordan normal form.

Functional Analysis · Mathematics 2010-08-02 George Costakis , Antonios Manoussos

In this paper, we classify Jordan superalgebras of dimension up to three over an algebraically closed field of characteristic different of two. Our main motivation to obtain such classification comes out from the intention to give an answer…

Rings and Algebras · Mathematics 2017-08-25 M. E. Martin

We obtain general upper bounds of the sizes and the numbers of Jordan blocks for the eigenvalues $\lambda \not= 1$ in the monodromies at infinity of polynomial maps.

Algebraic Geometry · Mathematics 2012-02-24 Yutaka Matsui , Kiyoshi Takeuchi

In this article we give bounds for the eigenvalues of a matrix, which can be seen as a common generalization of meet and join matrices and therefore also as a generalization of both GCD and LCM matrices. Although there are some results…

Number Theory · Mathematics 2015-11-06 Mika Mattila

We consider the density of states of structured Hermitian random matrices with a variance profile. As the dimension tends to infinity the associated eigenvalue density can develop a singularity at the origin. The severity of this…

Probability · Mathematics 2024-11-06 Torben Krüger , David Renfrew

In this article we give explicit descriptions of the multiplicities of some classes of monomial ideals. For instance, we give a formula for the multiplicities of all codimension 1 monomial ideals, and another formula for the multiplicities…

Commutative Algebra · Mathematics 2019-01-29 Guillermo Alesandroni

The problem of classifying all unitary R-matrices of arbitrary finite dimension that have precisely two distinct eigenvalues is described, working up to a natural equivalence relation given by the characters of their braid group…

Quantum Algebra · Mathematics 2026-03-23 Gandalf Lechner

We consider perturbations of a large Jordan matrix, either random and small in norm or of small rank. In both cases we show that most of the eigenvalues of the perturbed matrix are very close to a circle with centre at the origin. In the…

Spectral Theory · Mathematics 2007-05-23 E B Davies , Mildred Hager

In this paper we analyze the geometric structure and properties of a certain class of subsets of $\Bbb R^d$, known in the literature as 1-multicones, and here simply called multicones, which are quite natural generalizations of the…

Spectral Theory · Mathematics 2016-12-08 Michela Brundu , Marino Zennaro

We study in this article multiplicities of eigenvalues of tensors. There are two natural multiplicities associated to an eigenvalue $\lambda$ of a tensor: algebraic multiplicity $\operatorname{am}(\lambda)$ and geometric multiplicity…

Spectral Theory · Mathematics 2014-12-10 Shenglong Hu , Ke Ye

For a given complex square matrix $A$ with constant row sum, we establish two new eigenvalue inclusion sets. Using these bounds, first we derive bounds for the second largest and smallest eigenvalues of adjacency matrices of $k$-regular…

Combinatorics · Mathematics 2020-08-27 Ranjit Mehatari , M. Rajesh Kannan

For given k distinct complex conjugate pairs, l distinct real numbers, and a given graph G on 2k+l vertices with a matching of size at least k, we will show that there is a real matrix whose eigenvalues are the given numbers and its graph…

Spectral Theory · Mathematics 2018-03-16 Keivan Hassani Monfared

We characterize the eigenvalues and eigenvectors of a class of complex valued tridiagonal $n$ by $n$ matrices subject to arbitrary boundary conditions, i.e. with arbitrary elements on the first and last rows of the matrix. %By boundary…

Numerical Analysis · Mathematics 2018-01-17 J. J. P. Veerman , D. K. Hammond , Pablo E. Baldivieso

We present a prescription for forming matrices with specified eigenvalues and known eigenvectors. With this method, we can form Hermitian, anti-Hermitian, symmetric and general matrices with arbitrary eigenvalues. In addition we propose an…

Quantum Physics · Physics 2007-05-23 Habatwa V. Mweene