BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20250713T145910EDT-7171tUfSxG@132.216.98.100 DTSTAMP:20250713T185910Z DESCRIPTION:Title: Scattering theory for differential forms and its relatio n to cohomology\n Abstract: I will consider spectral theory of the Laplace operator on a manifold that is Euclidean outside a compact set. An example of such a setting is obstacle scattering where several compact pieces are removed from $R^d$. The spectrum of the operator on functions is absolute ly continuous. In the case of general $p$-forms eigenvalues at zero may ex ist\, the eigenspace consisting of L^2-harmonic forms. The dimension of th is space is computable by cohomological methods. I will present some new r esults concerning the detailed expansions of generalised eigenfunctions\, the scattering matrix\, and the resolvent near zero. These expansions cont ain the L^2-harmonic forms so there is no clear separation between the con tinuous and the discrete spectrum. This can be used to obtain more detaile d information about the L^2-cohomology as well as the spectrum. If I have time I will explain an application of this to physics. (joint work with Al den Waters)\n\n\n For zoom meeting information please contact dmitry.jakobs on [at] mcgill.ca\n DTSTART:20200619T160000Z DTEND:20200619T170000Z SUMMARY:Alexander Strohmaier (Leeds) URL:/mathstat/channels/event/alexander-strohmaier-leed s-322828 END:VEVENT END:VCALENDAR