# Luc C. Tartar

## University Professor of Mathematics, Emeritus

**Address:**

Department of Mathematical Sciences

Carnegie Mellon University

5000 Forbes Avenue

Pittsburgh, PA 15213

# Education

Dr.Sc., University of Paris

# Research

My research concerns the development of mathematical tools for studying the oscillating solutions of the nonlinear partial differential equations of continuum mechanics. For physical phenomena described at a microscopic level you need to understand what equations should be used at a macroscopic level, and the mathematical model used is based on different notions of weak convergence.

One aspect, called homogenization, is related to effective properties of mixtures. One problem is to obtain sharp bounds for effective coefficients while another is to understand how waves are damped in composite materials.

A second aspect is related to the phenomenon of relaxation in nonconvex optimization problems.

A third aspect concerns hyperbolic conservation laws and admissibility conditions for shocks, as well as propagation and interaction of oscillations for semilinear hyperbolic systems.

A fourth aspect concerns the adequation of these methods for questions like fluid turbulence, quantum mechanics and statistical mechanics.

# Select Publications

Tartar, L., "Homogenization, Compensated Compactness, H-measures," Lecture Notes in preparation.

Tartar, L. (1995), "Beyong YOUNG measures," Meccanica 30, 505–526.

Tartar, L. (1992), "On Mathematical Tools for Studying Partial Differential Equations of Continuum Physics: H-measures and Young Measures," Developments in Partial Differential Equations and Applications to Mathematical Physics, G. Buttazzo, G.P. Galdi & L. Zanghirati eds, 201–217, Plenum Press, New York, 1992.

Tartar, L. (1991), "H-measures and Applications," International Congress of Mathematicians, Kyoto, 1990, 1215–1223, Vol. II, Springer, 1991.

Tartar, L. (1990), "H-measures, a New Approach for Studying Homogenization, Oscillations and Concentration Effects in Partial Differential Equations," Proc. Roy. Soc. Edin. 115A: 193–230.

Tartar, L. (1989), "H-measures and Small Amplitude Homogenization," Random Media and Composites, R.V. Kohn & G.W. Milton eds, 89–99, SIAM, Philadelphia, 1989.