Geodesic stability, Lyapunov exponents, and quasinormal modes
Geodesic stability, Lyapunov exponents, and quasinormal modes
Geodesic motion determines important features of spacetimes. Null unstable geodesics are closely related to the appearance of compact objects to external observers and have been associated with the characteristic modes of black holes. By computing the Lyapunov exponent, which is the inverse of the instability time scale associated with this …