Ni, Jiaqi
Published in
Complex Analysis and Operator Theory

Suppose ω\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\omega $$\end{document} is a rotation-invariant Borel measure, the support of ω\documentclass[12pt]{minimal} \u...

Babahmed, M. El asri, A.

In this paper, the invariant Subspace Problem is studied for the class of non-Archimedean compact operators on an infinite-dimensional Banach space E over a nontrivial complete non-Archimedean valued field K. Our first main result (Theorem 9) asserts that if K is locally compact, then each compact operator on E possessing a quasi null vector admits...

Krivosheev, A. Krivosheeva, O.
Published in
Lobachevskii Journal of Mathematics

In this paper lower bounds for entire functions of exponential type and regular growth, zero sets of which have zero condensation indices, are obtained. In this case, the exceptional set consists of pairwise disjoint disks centered at zeroes. Sufficient conditions for radii of these circles are indicated. We also obtain a result on representation o...

Luongo, Angelo D’Annibale, Francesco
Published in
Meccanica

The linear dynamics of finite-dimensional viscoelastic structures is addressed in this paper. The equations of motion of a general, discrete or discretized, dynamical system, made of elements behaving as multiparameter viscoelastic solid models, are formulated in terms of internal variables, whose evolution is ruled by flow laws. The classical elas...

Cowen, Carl C. Gallardo-Gutiérrez, Eva A.
Published in
Concrete Operators

The Invariant Subspace Problem for Hilbert spaces is a long-standing question and the use of universal operators in the sense of Rota has been an important tool for studying such important problem. In this survey, we focus on Rota’s universal operators, pointing out their main properties and exhibiting some old and recent examples.

Zhang, Lei Lin, Yezhi
Published in
Nonlinear Dynamics

Based on the invariant subspace method, a symbolic computation scheme and its corresponding MAPLE package are developed to construct exact solutions for nonlinear evolution equations. In the symbolic computation scheme, a crucial step is constructing the linear differential equations as invariant subspaces that systems of evolution equations admin ...

Chattopadhyay, Arup Krishna Das, B. Sarkar, Jaydeb Sarkar, S.
Published in
Integral Equations and Operator Theory

Doubly commuting invariant subspaces of the Bergman space and the Dirichlet space over the unit polydisc Dn\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\mathbb{D}^n...

Wójcik, Paweł
Published in
Linear Algebra and Its Applications

For Banach spaces we consider the bounded linear operators which are surjective and noninjective. We show some general properties of such mappings. We examine whether such operators can be restricted to an involution or a projection. Thus, we will show that there exist many invariant subspaces for those operators. In respect to this, we will unders...

Di, Yanmei Zhang, Danda Shen, Shoufeng Zhang, Jun
Published in
Applied Mathematical Modelling

In this paper, conditional Lie–Bäcklund symmetry method is used to classify a class of inhomogeneous nonlinear diffusion equations ut=e-qxepxw(u)uxx. Equations admitted conditional Lie–Bäcklund symmetries can be either solved exactly or reduced to finite-dimensional dynamical systems. A number of concrete examples defined on the exponential and tri...

Gómez-Cubillo, Fernando Suchanecki, Zdzislaw Villullas, S.

An exact theory of irreversibility was proposed by Misra, Prigogine and Courbage, based on non-unitary similarity transformations Λ that intertwine reversible dynamics and irreversible ones. This would advocate the idea that irreversible behavior would originate at the microscopic level. Reversible evolution with an internal time operator have the ...