Victor Nistor
Université de Lorraine, Metz, France

We consider the regularity in broken Sobolev spaces for second order, strongly elliptic transmission problems. We consider two cases: that of polygonal domains (joint work with C. Bacuta and H. Li) and that of smooth domains and interfaces (but in arbitrary dimension, joint work with S. Labrunie and H. Mohsen). We show that the "constants" appearing in the classical estimates grow at most polynomialy in the coefficients of the operator.