Speaker: Kei-ichi Maeda (Waseda University, Tokyo)

Title: Relativistic dynamical systems and gravitational waves

Abstract:

After the discovery of the gravitational waves, gravitational wave physics and astronomy have provided us new information about strong gravitational phenomena and new physics. For example, speed of gravitational waves, equation of state at very high dense regions, constraint on gravitational theories, and so on. In order to observe gravitational waves, we have used the templates of emitted gravitational waves from a binary system. However, we may have a more complicated relativistic dynamical system in nature, which may not be integrable. We may expect chaotic behavior in such a system, for which it is very difficult to make appropriate templates. In this talk, we study chaos in a relativistic dynamical system of compact objects and the gravitational waves emitted from such a system. We then look for some characteristic features of the gravitational waves, which could be used in gravitational wave observation. We also discuss a hierarchical triple system with the Kozai-Lidov mechanism, which shows the oscillation between the eccentricity of inner binary and relative inclination. The evolution curve of the cumulative perihelion shift, which is indirect evidence of gravitational wave emission, will be bent since the gravitational waves are emitted strongly when the eccentricity becomes large. We then show the observability of gravitational waves from such a triple system. We also consider relativistic effects such as Lense-Thirring precession.

Room: Sala de Reuniões e Seminários (2-8.3) (2nd Floor of Physics Building)