On Friedrichs--Poincaré-type inequalities
The aim of the paper is to give direct proofs of Friedrichs-type inequalities in \(H^1(\Omega)\) and Poincaré-type inequalities in convenient subspaces of \(W^{1,p}(\Omega)\), \(1<p<\infty\), under certain assumptions on the domain \(\Omega\). Special attention is paid to the constants appearing in these inequalities and to their dependencies on the domain \(\Omega\).
scientific article; zbMATH DE number 2157699