Michel Rieutord (Institut de Recherche en Astrophysique et Planétologie, Université Paul Sabatier et Observatoire Midi-Pyrénées). Oscillations in rotating fluids: singularities of low-frequency modes in spherical shells.

Stars and planets are all rotating. Due to the conservation of angular momentum, this leads to specific oscillations known as inertial oscillations. These oscillations are low-frequency and own many peculiarities, like singularities. In this talk I will review the recent progresses in the understanding of these oscillations, especially those of a fluid in a spherical shell that are appropriate for celestial bodies and which raise many mathematical problems. I will also discuss how the properties of these waves might affect the oscillation spectrum of starsand planets, their internal dynamics or their response to a tidal forcing.