On the boundary conditions in estimating $\nabla \omega$ by div $\omega$ and curl $\omega .$

Gyula Csató, Olivier Kneuss, Dhanya Rajendran

In this paper we study under what boundary conditions the inequality $$\|\nablaω\|_{L^2(Ω)}^2\leq C\left(\|{\rm curl}ω\|_{L^2(Ω)}^2+ \|{\rm div}ω\|_{L^2(Ω)}^2+\|ω\|_{L^2(Ω)}^2\righ…