Perfectly-matched-layer truncation is exponentially accurate at high frequency

J Galkowski, D Lafontaine, E Spence - SIAM Journal on Mathematical Analysis, 2023 - SIAM
We consider a wide variety of Helmholtz scattering problems including scattering by
Dirichlet, Neumann, and penetrable obstacles. We consider a radial perfectly matched layer …

Super-localized orthogonal decomposition for high-frequency Helmholtz problems

P Freese, M Hauck, D Peterseim - SIAM Journal on Scientific Computing, 2024 - SIAM
We propose a novel variant of the Localized Orthogonal Decomposition (LOD) method for
time-harmonic scattering problems of Helmholtz type with high wavenumber. On a coarse …

Wavenumber-explicit stability and convergence analysis of hp finite element discretizations of Helmholtz problems in piecewise smooth media

M Bernkopf, T Chaumont-Frelet, JM Melenk - arXiv preprint arXiv …, 2022 - arxiv.org
We present a wavenumber-explicit convergence analysis of the hp finite element method
applied to a class of heterogeneous Helmholtz problems with piecewise analytic coefficients …

Does the Helmholtz boundary element method suffer from the pollution effect?

J Galkowski, EA Spence - Siam Review, 2023 - SIAM
In d dimensions, accurately approximating an arbitrary function oscillating with frequency
\lesssimk requires ∼ k^d degrees of freedom. A numerical method for solving the Helmholtz …

Decompositions of high-frequency Helmholtz solutions via functional calculus, and application to the finite element method

J Galkowski, D Lafontaine, EA Spence… - SIAM Journal on …, 2023 - SIAM
Over the last 10 years, results from [JM Melenk and S. Sauter, Math. Comp., 79 (2010), pp.
1871–1914],[JM Melenk and S. Sauter, SIAM J. Numer. Anal., 49 (2011), pp. 1210–1243],[S …

Convergence of parallel overlapping domain decomposition methods for the Helmholtz equation

S Gong, MJ Gander, IG Graham, D Lafontaine… - Numerische …, 2022 - Springer
We analyse parallel overlapping Schwarz domain decomposition methods for the Helmholtz
equation, where the exchange of information between subdomains is achieved using first …

A sharp relative-error bound for the Helmholtz h-FEM at high frequency

D Lafontaine, EA Spence, J Wunsch - Numerische Mathematik, 2022 - Springer
For the h-finite-element method (h-FEM) applied to the Helmholtz equation, the question of
how quickly the meshwidth h must decrease with the frequency k to maintain accuracy as k …

Wavenumber-explicit parametric holomorphy of Helmholtz solutions in the context of uncertainty quantification

EA Spence, J Wunsch - SIAM/ASA Journal on Uncertainty Quantification, 2023 - SIAM
A crucial role in the theory of uncertainty quantification (UQ) of PDEs is played by the
regularity of the solution with respect to the stochastic parameters; indeed, a key property …

Applying GMRES to the Helmholtz equation with strong trapping: how does the number of iterations depend on the frequency?

P Marchand, J Galkowski, EA Spence… - Advances in …, 2022 - Springer
We consider GMRES applied to discretisations of the high-frequency Helmholtz equation
with strong trapping; recall that in this situation the problem is exponentially ill-conditioned …

Eigenvalues of the truncated Helmholtz solution operator under strong trapping

J Galkowski, P Marchand, EA Spence - SIAM Journal on Mathematical …, 2021 - SIAM
For the Helmholtz equation posed in the exterior of a Dirichlet obstacle, we prove that if there
exists a family of quasimodes (as is the case when the exterior of the obstacle has stable …