Twodimensional anisotropic variational problems

Abstract

We consider local minimizers u:\Omega\rightarrow\mathbb{R}^{N}, \Omega a domain in \mathbb{R}^{2}, of the variational integral \int_{\Omega}f(\nabla u)dx with integrand f of upper (lower) growth rate q(s). We show using a lemma due to Frehse and Seregin that u has Hölder contiuous first derivatives provided that q < 2s.