Inserted: 4 jan 2002
Journal: Proc. R. Soc. Lond. A
We study dielectric breakdown for composites made of two isotropic phases. We show that Sachs' bound is optimal. This simple example is used to illustrate a variational principle which departs from the traditional one. We also derive the usual variational principle by elementary means without appealing to the technology of convex duality.
Keywords: $\Gamma$-convergence, composites, bounds, Dielectric breakdown, variational principle in $L^\infty$