author={St'ephane Nonnenmacher},
  journal={Proceedings of the International Congress of Mathematicians (ICM 2018)},
  • S. Nonnenmacher
  • Published 1 May 2019
  • Mathematics
  • Proceedings of the International Congress of Mathematicians (ICM 2018)
The study of wave propagation outside bounded obstacles uncovers the existence of resonances for the Laplace operator, which are complex-valued generalized eigen-values, relevant to estimate the long time asymptotics of the wave. In order to understand distribution of these resonances at high frequency, we employ semiclassical tools, which leads to considering the classical scattering problem, and in particular the set of trapped trajectories. We focus on "chaotic" situations, where this set is… 
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