English
Related papers

Related papers: Shape Taylor expansion for wave scattering problem…

200 papers

For parameter identification problems the Fr\'echet-derivative of the parameter-to-state map is of particular interest. In many applications, e.g. in seismic tomography, the unknown quantity is modeled as a coefficient in a linear…

Analysis of PDEs · Mathematics 2019-01-30 Thies Gerken , Simon Grützner

In this paper we study propagation of the high frequency electromagnetic waves in a curved spacetime. We discuss a so call spinoptics approach which generalizes a well known geometric optics approximation and allows one to take into account…

General Relativity and Quantum Cosmology · Physics 2024-08-26 Valeri P. Frolov

The phenomenon of Taylor or shear-induced dispersion of a non-passive scalar field in a pulsatile pipe flow is investigated, accounting for the scalar field's influence on fluid density and transport coefficients. By employing multiple…

Fluid Dynamics · Physics 2026-03-13 Prabakaran Rajamanickam , Adam D. Weiss

This paper considers an inverse problem for the classical wave equation in an exterior domain. It is a mathematical interpretation of an inverse obstacle problem which employs the dynamical scattering data of acoustic wave over a finite…

Analysis of PDEs · Mathematics 2020-01-27 Masaru Ikehata

Particle Flow Filters perform the measurement update by moving particles to a different location rather than modifying the particles' weight based on the likelihood. Their movement (flow) is dictated by a drift term, which continuously…

Computational Engineering, Finance, and Science · Computer Science 2025-07-04 Simone Servadio

In this paper, a linear model based on multiple measurement vectors model is proposed to formulate the inverse scattering problem of highly conductive objects at one single frequency. Considering the induced currents which are mostly…

Signal Processing · Electrical Eng. & Systems 2019-06-27 Shilong Sun , Bert Jan Kooij , Alexander G. Yarovoy

The purpose of this research is to describe an efficient iterative method suitable for obtaining high accuracy solutions to high frequency time-harmonic scattering problems. The method allows for both refinement of local polynomial degree…

Computational Physics · Physics 2018-12-26 Ryan Galagusz , Steve McFee

The concept of topological derivative has proved effective as a qualitative inversion tool for a wave-based identification of finite-sized objects. Although for the most part, this approach remains based on a heuristic interpretation of the…

Numerical Analysis · Mathematics 2020-01-08 Marc Bonnet , Fioralba Cakoni

In this note, we study the long-time dynamics of passive scalars driven by rotationally symmetric flows. We focus on identifying precise conditions on the velocity field in order to prove enhanced dissipation and Taylor dispersion in…

Analysis of PDEs · Mathematics 2023-05-30 Michele Coti Zelati , Michele Dolce , Chia-Chun Lo

Multiple scattering methods are widely used to reduce the computational complexity of acoustic or electromagnetic scattering problems when waves propagate through media containing many identical inclusions. Historically, this numerical…

Numerical Analysis · Mathematics 2024-08-07 Carlos Borges , Leslie Greengard , Michael O'Neil , Manas Rachh

We achieve efficient shaping of superscattering by radially anisotropic nanowires relying on resonant multipolar interferences. It is shown that the radial anisotropy of refractive index can be employed to resonantly overlap electric and…

Optics · Physics 2017-09-13 Wei Liu

Scattering amplitudes in quantum field theory are independent of the field parameterization, which has a natural geometric interpretation as a form of `coordinate invariance.' Amplitudes can be expressed in terms of Riemannian curvature…

High Energy Physics - Theory · Physics 2023-02-08 Timothy Cohen , Nathaniel Craig , Xiaochuan Lu , Dave Sutherland

An extension of the Gutzwiller trace formula is given that includes diffraction effects due to hard wall scatterers or other singularities. The new trace formula involves periodic orbits which have arcs on the surface of singularity and…

chao-dyn · Physics 2016-08-14 Gábor Vattay , Andreas Wirzba , Per E. Rosenqvist

We develop a method for optimization in shape spaces, i.e., sets of surfaces modulo re-parametrization. Unlike previously proposed gradient flows, we achieve superlinear convergence rates through a subtle approximation of the shape Hessian,…

Computer Vision and Pattern Recognition · Computer Science 2014-04-15 J. Balzer , S. Soatto

Properties of the wave function equivalent potentials introduced by HAL QCD collaboration are studied in a non-relativistic coupled-channel model. The derivative expansion is generalized, and then applied to the energy-independent and…

Nuclear Theory · Physics 2017-05-03 Takuya Sugiura , Noriyoshi Ishii , Makoto Oka

We investigate higher-order geometric $k$-splines for template matching on Lie groups. This is motivated by the need to apply diffeomorphic template matching to a series of images, e.g., in longitudinal studies of Computational Anatomy. Our…

Chaotic Dynamics · Physics 2015-05-20 F. Gay-Balmaz , D. D. Holm , D. M. Meier , T. S. Ratiu , F. -X. Vialard

Effects of nonlinearity in Thomson scattering of a high intensity laser pulse from electrons are analyzed. Analytic expressions for laser pulse shaping in amplitude and frequency are obtained which control spectrum broadening for…

Plasma Physics · Physics 2014-12-09 S. G. Rykovanov , C. G. R. Geddes , C. B. Schroeder , E. Esarey , W. P. Leemans

In this paper, we use graph theory to solve wave scattering problems in the discrete dipole approximation. As a key result of this work, in the presence of active scatterers, we present a systematic method to find arbitrary large-order zero…

Optics · Physics 2023-06-14 Stefano Scali , Janet Anders , Simon A. R. Horsley

We consider the inverse problem of determining the geometry of penetrable objects from scattering data generated by one incident wave at a fixed frequency. We first study an orthogonality sampling type method which is fast, simple to…

Numerical Analysis · Mathematics 2022-07-21 Thu Le , Dinh-Liem Nguyen , Vu Nguyen , Trung Truong

In this paper we review the results of the author on the theory of scalar and vector wave scattering by small bodies of an arbitrary shape with the emphasis on practical applicability of the formulas obtained and on the mathematical rigor…

Mathematical Physics · Physics 2007-05-23 A. G. Ramm