English
Related papers

Related papers: Eigenstructure of the linearized electrical impeda…

200 papers

This paper is devoted to studying impedance eigenvalues (that is, eigenvalues of a particular Dirichlet-to-Neumann map) for the time harmonic linear elastic wave problem, and their potential use as target-signatures for fluid-solid…

Analysis of PDEs · Mathematics 2022-01-31 Michael Levitin , Peter Monk , Virginia Selgas

We consider Inverse Electrical Impedance Tomography (EIT) problem on recovering electrical conductivity and potential in the body based on the measurement of the boundary voltages on the $m$ electrodes for a given electrode current. The…

Optimization and Control · Mathematics 2024-12-17 Ugur G. Abdulla , Saleheh Seif

Light injected into a spherical dielectric body may be confined very efficiently via the mechanism of total internal reflection. The frequencies that are most confined are called resonances. If the shape of the body deviates from the…

Optics · Physics 2020-09-30 Julius Gohsrich

In this second part of our series of papers, we develop an abstract framework suitable for de Rham complexes that depend on a parameter belonging to an arbitrary Banach space. Our primary focus is on spectral perturbation problems and the…

Spectral Theory · Mathematics 2025-02-19 Pier Domenico Lamberti , Dirk Pauly , Michele Zaccaron

We consider generalized operator eigenvalue problems in variational form with random perturbations in the bilinear forms. This setting is motivated by variational forms of partial differential equations with random input data. The…

Numerical Analysis · Mathematics 2024-06-13 Jürgen Dölz , David Ebert

We show that the perturbative expansion of the two-level correlation function, $R(\omega)$, in disordered conductors can be understood semiclassically in terms of self-intersecting particle trajectories. This requires the extension of the…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Robert A. Smith , Igor V. Lerner , Boris L. Altshuler

A large i.i.d. random matrix with deterministic low-rank perturbation has been extensively studied, particularly in the aspects of the ESD (Empirical Spectral Distribution) and the outliers of eigenvalues. In this work, we investigate the…

Information Theory · Computer Science 2025-06-24 Kun Chen , Zhihua Zhang

We develop the shape derivative analysis of solutions to the problem of scattering of time-harmonic electromagnetic waves by a bounded penetrable obstacle. Since boundary integral equations are a classical tool to solve electromagnetic…

Numerical Analysis · Mathematics 2010-02-22 Martin Costabel , Frédérique Le Louër

We study a perturbed Floquet Hamiltonian $K+\beta V$ depending on a coupling constant $\beta$. The spectrum $\sigma(K)$ is assumed to be pure point and dense. We pick up an eigen-value, namely $0\in\sigma(K)$, and show the existence of a…

Quantum Physics · Physics 2008-11-26 P. Duclos , P. Stovicek , M. Vittot

We present a theoretical framework for deriving the general $n$-th order Fr\'echet derivatives of singular values in real rectangular matrices, by leveraging reduced resolvent operators from Kato's analytic perturbation theory for…

Machine Learning · Statistics 2025-11-17 Róisín Luo , James McDermott , Colm O'Riordan

This work addresses the Galerkin isogeometric discretization of the one-dimensional Laplace eigenvalue problem subject to homogeneous Dirichlet boundary conditions on a bounded interval. We employ GLT theory to analyze the behavior of the…

Numerical Analysis · Mathematics 2025-10-15 Lamsahel Noureddine , Abdeladim El Akri , Ahmed Ratnani

The multifrequency electrical impedance tomography consists in retrieving the conductivity distribution of a sample by injecting a finite number of currents with multiple frequencies. In this paper we consider the case where the…

Numerical Analysis · Mathematics 2017-04-18 Habib Ammari , Faouzi Triki , Chun-Hsiang Tsou

We consider the scattering problem on locally perturbed periodic penetrable dielectric layers, which is formulated in terms of the full vector-valued time-harmonic Maxwell's equations. The right-hand side is not assumed to be periodic. At…

Analysis of PDEs · Mathematics 2019-08-23 Alexander Konschin

A low-order nonconforming finite element discretization of a smooth de Rham complex starting from the $H^2$ space in three dimensions is proposed, involving an $H^2$-nonconforming finite element space, a new tangentially continuous…

Numerical Analysis · Mathematics 2025-12-05 Xuewei Cui , Xuehai Huang

A Gelfand triplet for the Hamiltonian H of the infinite-dimensional Friedrichs model on the positive half line with Hilbert-Schmidt perturbations is constructed such that exactly the resonances (poles of the inverse of the Livsic-matrix)…

Mathematical Physics · Physics 2007-05-23 Hellmut Baumgärtel

The present article is devoting a numerical approach for solving a fractional partial differential equation (FPDE) arising from electromagnetic waves in dielectric media (EMWDM). The truncated Bernoulli and Hermite wavelets series with…

Numerical Analysis · Mathematics 2021-04-05 Vijay Kumar Patel

Geometrically frustrated magnetic molecules have attracted a lot of interest in the field of molecular magnetism as well as frustrated Heisenberg antiferromagnets. In this article we demonstrate how an approximate diagonalization scheme can…

Strongly Correlated Electrons · Physics 2018-10-23 R. Schnalle , A. Laeuchli , J. Schnack

We consider a variant of the classic Steklov eigenvalue problem, which arises in the study of the best trace constant for functions in Sobolev space. We prove that the elementary symmetric functions of the eigenvalues depend…

Analysis of PDEs · Mathematics 2012-10-15 Pier Domenico Lamberti

We develop the shape derivative analysis of solutions to the problem of scattering of time-harmonic electromagnetic waves by a bounded penetrable obstacle. Since boundary integral equations are a classical tool to solve electromagnetic…

Numerical Analysis · Mathematics 2012-03-19 Martin Costabel , Frédérique Le Louër

In this work we develop and analyze an adaptive finite element method for efficiently solving electrical impedance tomography -- a severely ill-posed nonlinear inverse problem for recovering the conductivity from boundary voltage…

Numerical Analysis · Mathematics 2019-05-16 Bangti Jin , Yifeng Xu , Jun Zou