Laconicity and redundancy of Toeplitz matrices.
We find the limit distributions for a spectrum of a system of n particles governed by a k-body interaction. The hamiltonian of this system is modelled by a Gaussian random matrix. We show that the limit distribution is a q-deformed Gaussian distribution with the deformation parameter q depending on the fraction k/√n. The family of q-deformed Gaussian distributions include the Gaussian distribution and the semicircular law; therefore our result is a generalization of the results of Wigner [Wig1,...
The study on limit points of eigenvalues of undirected graphs was initiated by A. J. Hoffman in 1972. Now we extend the study to digraphs. We prove: 1. Every real number is a limit point of eigenvalues of graphs. Every complex number is a limit point of eigenvalues of digraphs. 2. For a digraph , the set of limit points of eigenvalues of iterated subdivision digraphs of is the unit circle in the complex plane if and only if has a directed cycle. 3. Every limit point of eigenvalues of a set...
The methods to establish the limiting spectral distribution (LSD) of large dimensional random matrices includes the well-known moment method which invokes the trace formula. Its success has been demonstrated in several types of matrices such as the Wigner matrix and the sample covariance matrix. In a recent article Bryc, Dembo and Jiang [Ann. Probab.34 (2006) 1–38] establish the LSD for random Toeplitz and Hankel matrices using the moment method. They perform the necessary counting of terms in the...
The set of all Boolean matrices is denoted by . We call a matrix regular if there is a matrix such that . In this paper, we study the problem of characterizing linear operators on that strongly preserve regular matrices. Consequently, we obtain that if , then all operators on strongly preserve regular matrices, and if , then an operator on strongly preserves regular matrices if and only if there are invertible matrices and such that for all , or and for all .
The maximal column rank of an m by n matrix is the maximal number of the columns of A which are linearly independent. We compare the maximal column rank with rank of matrices over a nonbinary Boolean algebra. We also characterize the linear operators which preserve the maximal column ranks of matrices over nonbinary Boolean algebra.
The Boolean rank of a nonzero Boolean matrix is the minimum number such that there exist an Boolean matrix and a Boolean matrix such that . In the previous research L. B. Beasley and N. J. Pullman obtained that a linear operator preserves Boolean rank if and only if it preserves Boolean ranks and . In this paper we extend this characterizations of linear operators that preserve the Boolean ranks of Boolean matrices. That is, we obtain that a linear operator preserves Boolean rank...
Let be a Boolean matrix. The isolation number of is the maximum number of ones in such that no two are in any row or any column (that is they are independent), and no two are in a submatrix of all ones. The isolation number of is a lower bound on the Boolean rank of . A linear operator on the set of Boolean matrices is a mapping which is additive and maps the zero matrix, , to itself. A mapping strongly preserves a set, , if it maps the set into the set and the complement of...