Chaotic dynamics in the X-ray variability of Her X-1

Abstract

In addition to its fundamental implications on the foundations of statistical physics, the concept of deterministic chaos in dynamical systems has provided considerable impact concerning the experimental characterization of dynamical systems. There exist different methods to derive invariants of such systems from measured time series (for an overview, see Ref.1). The determination of these invariants is possible, if only one single variable of a generally complex system is accessible by observation. This issue underlines the particular importance for astrophysical systems, for which the only observable variable is the electromagnetic radiation.