Publikace ÚTF

Dynamics of time-like geodesics in the static and axially symmetric field of a black hole surrounded by a thin disc is studied by two recurrence methods, the recurrence plots (RPs) and the average of directional vectors (ADVs). Their results supplement the information obtained before from Poincaré surfaces of section and from phase-variable evolutions and the corresponding power spectra. The occurrence of chaos due to the presence of ambient matter may be important for evolution and appearance of astrophysical black-hole systems.