2013/11/01 by Egert, Moritz, Haller-Dintelmann, Robert, Tolksdorf, Patrick · 1 citation
#35J05 #35J57 #46E35 #FOS: Mathematics #Functional Analysis (math.FA)
paper · doi:10.48550/arxiv.1311.0302
We consider the negative Laplacian subject to mixed boundary conditions on a bounded domain. We prove under very general geometric assumptions that slightly above the critical exponent (1)/(2) its fractional power domains still coincide with suitable Sobolev spaces of optimal regularity. In combination with a reduction theorem recently obtained by the authors, this solves the Kato Square Root Problem for elliptic second order operators and systems in divergence form under the same geometric assumptions.