Free boundary methods and non-scattering phenomena

Autor: Mikko Salo, Henrik Shahgholian
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Zdroj: Research in the Mathematical Sciences
ISSN: 2197-9847
2522-0144
Popis: We study a question arising in inverse scattering theory: given a penetrable obstacle, does there exist an incident wave that does not scatter? We show that every penetrable obstacle with real-analytic boundary admits such an incident wave. At zero frequency, we use quadrature domains to show that there are also obstacles with inward cusps having this property. In the converse direction, under a nonvanishing condition for the incident wave, we show that there is a dichotomy for boundary points of any penetrable obstacle having this property: either the boundary is regular, or the complement of the obstacle has to be very thin near the point. These facts are proved by invoking results from the theory of free boundary problems.
Comment: 18 pages
Databáze: OpenAIRE