Maximum principle for viscosity sub solutions and viscosity sub solutions of the Laplacian
Summary: The aim of this paper is to characterize the upper semicontinuous (resp. lower semicontinuous) viscosity sub (resp. super) solutions of the Laplacian which do not take the value \(+\infty\) (resp. \(-\infty\)) as precisely the sub (resp. super) harmonic functions.
upper and lower semicontinuous sub- and super solutions
scientific article; zbMATH DE number 591116