3 papers
math.NA2021
On the derivation of guaranteed and p-robust a posteriori error estimates for the Helmholtz equation
T. Chaumont-Frelet, A. Ern, M. Vohralík
We propose a novel a posteriori error estimator for conforming finite element discretizations of two- and three-dimensional Helmholtz problems. The estimator is based on an equilib…
math.NA2020
Polynomial-degree-robust H(curl)-stability of discrete minimization in a tetrahedron
Théophile Chaumont-Frelet, Alexandre Ern, Martin Vohralík
We prove that the minimizer in the Nédélec polynomial space of some degree p > 0 of a discrete minimization problem performs as well as the continuous minimizer in H(curl), up to a…
math.NA2020
A generalized finite element method for problems with sign-changing coefficients
Théophile Chaumont-Frelet, Barbara Verfürth
Problems with sign-changing coefficients occur, for instance, in the study of transmission problems with metamaterials. In this work, we present and analyze a generalized finite el…