HOMOGENIZATION OF HIGH-CONTRAST MUMFORD-SHAH ENERGIES

We prove a homogenization result for Mumford-Shah-type energies associated to a brittle composite material with weak inclusions distributed periodically at a scale epsilon > 0. The matrix and the inclusions in the material have the same elastic moduli but very different toughness moduli, with the ratio of the toughness modulus in the matrix and in the inclusions being 1/beta(epsilon), with beta(epsilon) > 0 small. We show that the high-contrast behavior of the composite leads to the emergence of interesting effects in the limit: The volume and surface energy densities interact by Gamma-convergence, and the limit volume energy is not a quadratic form in the critical scaling beta(epsilon) = epsilon, unlike the epsilon-energies, and unlike the extremal limit cases.