Séminaire / Seminar GReCO |
« To turbulence in black holes and back again » |
L. Lehner |
Motivated by the fluid-gravity correspondence I discuss how turbulence can arise in gravity and its relation to black hole perturbations. In particular, rapidly-spinning black holes can display turbulent gravitational behavior which is mediated by a new type of parametric instability. This instability transfers energy from higher temporal and azimuthal spatial frequencies to lower frequencies - a phenomenon reminiscent of the inverse energy cascade displayed by 2+1- dimensional turbulent fluids. This finding reveals a path towards gravitational turbulence for perturbations of rapidly-spinning black holes, and provides evidence for gravitational turbulence in an asymptotically flat spacetimes. Interestingly, this finding predicts observable gravitational wave signatures from such phenomena in black hole binaries with high spins and gives a gravitational description of turbulence relevant to the fluid-gravity duality.
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mercredi 16 juillet 2014 - 11:00 Salle des séminaires Évry Schatzman Institut d'Astrophysique de Paris |
Pages web du séminaire / Seminar's webpage |