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\noindent{\bf Mathematisches Oberseminar} {\it PDG und
Spektraltheorie} (SoSe 2015).

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\noindent{\bf Date:} 16.06.2015.

\noindent{\bf Time and place:} {\bf 16:15} in B 134.

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\noindent{\bf Speaker:} Rafael Tiedra (Pontifical Catholic University of Chile).

\noindent{\bf Titel:} {\it Spectral and scattering properties at thresholds for the Laplacian in a half-space with a periodic boundary condition.}


\noindent{\bf Abstract:}

\noindent  For the scattering system given by the Laplacian in a
half-space with a periodic boundary condition, we derive resolvent
expansions at embedded thresholds, we prove the continuity of the
scattering matrix, and we establish new formulas for the wave
operators. \\
This is a joint work with Serge Richard (University of
Nagoya). 


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Thomas {\O}stergaard S{\o}rensen

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