Journal Home Page Cumulative Index List of all Volumes Complete Contentsof this Volume Previous Article Journal of Convex Analysis 13 (2006), No. 1, 037--050Copyright Heldermann Verlag 2006 Estimates of Quasiconvex Polytopes in the Calculus of Variations Kewei Zhang Dept. of Mathematics, University of Sussex, Falmer, Brighton BN1 9RF, Great Britain k.zhang@sussex.ac.uk [Abstract-pdf] \def\dist{\operatorname{dist}} We give direct estimates for the quasiconvex polytopes $Q(K)$ generated by a finite set $K\subset M^{N\times n}$. More precisely, we bound the quasiconvex envelope $Q\dist(\cdot,K)$ near a convex exposed face of $C(X)$ which does not have rank-one connections. Our estimates depend on the weak-(1,1) bounds for certain singular integral operators and the geometric features of the convex polytope $C(K)$. We show by an example that our estimate is local' and independent of the size' of $K$, hence it is a better estimate than the polyconvex hull $P(K)$ which is `size' dependent. Keywords: Direct estimates, quasiconvex polytopes, quasiconvex envelope, singular integral operators, polyconvex hull. [ Fulltext-pdf  (412  KB)] for subscribers only.