Detailed program of the event: - 4 p.m. (sharp) in SRZ 216/217: Introductory talk for PhD students and postdocs by Dr. Francesco Deangelis - 4.30 p.m. Coffee and tea will be served in the Cluster Lounge (Orléans-Ring 12) - 5 p.m. (sharp) in SRZ 216/217: Colloquium-talk by Prof. Dr. Antoine Gloria: Title: Effective ellipticity for high contrast homogenization Abstract: Homogenization is the art of averaging coefficients of differential operators in a consistent way. It is the mathematical theory associated with composite materials. The theory is by-now well-understood for linear elliptic equations with random coefficients that are uniformly bounded and elliptic. For applications to mathematical physics and to more contemporary homogenization problems, it is however desirable to move away from uniform ellipticity. In this colloquium I will introduce a concept of effective ellipticity field and ellipticity radius, which quantifies how and at which scale an elliptic operator with (degenerate and unbounded) stationary ergodic coefficients is close to a uniformly elliptic operator. Combined with nonlinear concentration of measure, this allows to extend quantitative homogenization theory to the setting of high- (and even infinite-) contrast. - 6 p.m. Informal reception in the Cluster Lounge (Orléans-Ring 12)