E. Vesalainen (Helsinki University)

Recently, Blasten, Päivärinta and Sylvester proved that, in acoustic medium scattering, rectangular corners in the scatterer (suitably understood) always cause non-trivial scattering at all energies. We describe how to extend this result to all corners of angle smaller than 180° in two dimensions, and to all, except possibly numerably many, circular conical corners in three dimensions.

This is joint work with L. Päivärinta and M. Salo.