activity
20102026
most citedStability Analysis for Magnetic Resonance Elastography

3 citations · 13 across the 19 of their papers we have counts for

collaborators

24 papers

math.AP2026

The scattering matrix for the p-form Laplacian on asymptotically conic manifolds

Nelia Charalambous, Alden Waters

The Hodge decomposition at infinity gives rise to distinct tangential scattering channels for differential forms on asymptotically conic manifolds. We construct co-closed generaliz…

math.AP2025

A Pöschl--Teller approximation to the wave equation outside a torus

Ronald Quirchmayr, Alden Waters

We prove dispersive estimates for an approximation to the wave equation in the exterior of a torus. Because no separation of variables into a basis of eigenfunctions and eigenvalue…

math.AP2023

Dispersive Estimates for Maxwell's Equations in the Exterior of a Sphere

Alden Waters, Yan-Long Fang

The goal of this article is to establish general principles for high frequency dispersive estimates for Maxwell's equation in the exterior of a perfectly conducting ball. We constr…

math.NA2022

Approximation of the non-linear water hammer problem by a Lax-Wendroff finite difference scheme

Hugo Carrillo-Lincopi, Alden Waters, Teke Xu

We study the water hammer problem in the case of a sudden closing of a valve upstream, and we consider a Lax-Wendroff finite difference scheme in order to obtain a numerical soluti…

math.AP2021

The relative trace formula in electromagnetic scattering and boundary layer operators

Alexander Strohmaier, Alden Waters

This paper establishes trace-formulae for a class of operators defined in terms of the functional calculus for the Laplace operator on divergence-free vector fields with relative a…

math.SP2021

The Birman-Krein formula for differential forms and electromagnetic scattering

Alexander Strohmaier, Alden Waters

We consider scattering theory of the Laplace Beltrami operator on differential forms on a Riemannian manifold that is Euclidean near infinity. Allowing for compact boundaries of lo…

math.AP2020

Observability for Schrödinger equations with quadratic Hamiltonians

Alden Waters

We consider time dependent harmonic oscillators and construct a parametrix to the corresponding Schrödinger equation using Gaussian wavepackets. This parametrix of Gaussian wavepac…

math.AP2020

Analytic properties of heat equation solutions and reachable sets

Alexander Strohmaier, Alden Waters

There recently has been some interest in the space of functions on an interval satisfying the heat equation for positive time in the interior of this interval. Such functions were…

math.SP2020

A relative trace formula for obstacle scattering

Florian Hanisch, Alexander Strohmaier, Alden Waters

We consider the case of scattering of several obstacles in for . In this setting the absolutely continuous part of the Laplace operator with Dirichlet…

math.AP2019

Geometric and Obstacle Scattering at Low Energy

Alexander Strohmaier, Alden Waters

We consider scattering theory of the Laplace Beltrami operator on differential forms on a Riemannian manifold that is Euclidean at infinity. The manifold may have several boundary…

math.OC2018

Rank optimality for the Burer-Monteiro factorization

Irène Waldspurger, Alden Waters

When solving large scale semidefinite programs that admit a low-rank solution, an efficient heuristic is the Burer-Monteiro factorization: instead of optimizing over the full matri…

math.AP2018

Asymptotics for optimal design problems for the Schrödinger equation with a potential

Alden Waters, Ekaterina Merkurjev

We study the problem of optimal observability and prove time asymptotic observability estimates for the Schrödinger equation with a potential in , with $Ω\subset \ma…

math.AP2018

Unique Determination of Sound Speeds for Coupled Systems of Semi-linear Wave Equations

Alden Waters

We consider coupled systems of semi-linear wave equations with different sound speeds on a finite time interval and a bounded Lipschitz domain in , with b…

math.AP2015

Low Regularity Ray Tracing for Wave Equations with Gaussian beams

Alden Waters

We prove observability estimates for oscillatory Cauchy data modulo a small kernel for -dimensional wave equations with space and time dependent and coefficients…

math.AP2015

Recovery of the sound speed for the Acoustic wave equation from phaseless measurements

Joonas Ilmavirta, Alden Waters

We recover the higher order terms for the acoustic wave equation from measurements of the modulus of the solution. The recovery of these coefficients is reduced to a question of st…

math.AP2015★ 3 cited

Lower resolvent bounds and Lyapunov exponents

Semyon Dyatlov, Alden Waters

We prove a new polynomial lower bound on the scattering resolvent. For that, we construct a quasimode localized on a trajectory which is trapped in the past, but not in the fut…

math.AP2015★ 2 cited

Stability Analysis in Magnetic Resonance Elastography II

Heiko Gimperlein, Alden Waters

We consider the inverse problem of finding unknown elastic parameters from internal measurements of displacement fields for tissues. In the sequel to Ammari, Waters, Zhang (2015),…

math.AP2015

A deterministic optimal design problem for the heat equation

Heiko Gimperlein, Alden Waters

For the heat equation on a bounded subdomain of , we investigate the optimal shape and location of the observation domain in observability inequalites. A new deco…

math.AP2014★ 3 cited

Stability Analysis for Magnetic Resonance Elastography

Habib Ammari, Alden Waters, Hai Zhang

We consider the inverse problem of finding unknown elastic parameters from internal measurements of displacement fields for tissues. The measurements are made on the entirety of a…

math.AP2013

Stability estimate and the Aharonov-Bohm effect for the Klein-Gordon equation with time-dependent vector potentials

Ricardo Salazar, Alden Waters

We consider the relativistic Schrödinger (Gordon-Klein) equation with a time dependent vector and a scalar potential on a bounded cylindrical domain. Using a standard Geometric Opt…

math.AP2013★ 2 cited

Stability for Time Dependent X-ray Transforms and Applications

Alden Waters

We prove a logarithmic stability estimate for the time dependent X-ray transform on . To do so, we extend a known result by Begmatov for the stabi…

math.AP2013★ 1 cited

Stable determination of X-ray transforms of time dependent potentials from the dynamical Dirichlet-to-Neumann map

Alden Waters

We consider compact smooth Riemmanian manifolds with boundary of dimension greater than or equal to two. For the initial-boundary value problem for the wave equation with a lower o…

math.AP2012★ 2 cited

Spectral Rigidity for Periodic Schrödinger Operators in Dimension 2

Alden Waters

We consider two dimensional real-valued analytic potentials for the Schrödinger equation which are periodic over a lattice . Under certain assumptions on the form of the potenti…

math.AP2010

A Parametrix Construction for the Wave Equation with Low Regularity Coefficients Using a Frame of Gaussians

Alden Waters

We construct a frame of complex Gaussians for the space of functions. When propagated along bicharacteristics for the wave equation, the frame can be used to bu…