3 papers
math.NA2026
Guaranteed inf-sup bounds and existence verification for semilinear elliptic problems via nonconforming finite elements
Benedikt Gräßle
A Newton--Kantorovich-type argument enables the a posteriori existence verification of a unique regular root near a computed approximation, purely from computable data. This framew…
math.AP2025
Stable skeleton integral equations for general coefficient Helmholtz transmission problems
Benedikt Gräßle, Ralf Hiptmair, Stefan Sauter
A novel variational formulation of layer potentials and boundary integral operators generalizes their classical construction by Green's functions, which are not explicitly availabl…
math.AP2025
Optimal trace norms for Helmholtz problems
Benedikt Gräßle
The natural energy norm for Helmholtz problems is weighted with the wavenumber modulus and induces weighted norms on the trace spaces by minimal extens…