Leaking from the phase space of the Riemann-Liouville fractional standard map
arXiv:2302.13008 · doi:10.1016/j.chaos.2023.113532
Abstract
In this work we characterize the escape of orbits from the phase space of the Riemann-Liouville (RL) fractional standard map (fSM). The RL-fSM, given in action-angle variables, is derived from the equation of motion of the kicked rotor when the second order derivative is substituted by a RL derivative of fractional order . Thus, the RL-fSM is parameterized by and which control the strength of nonlinearity and the fractional order of the RL derivative, respectively. Indeed, for and given initial conditions, the RL-fSM reproduces Chirikov's standard map. By computing the survival probability and the frequency of escape , for a hole of hight placed in the action axis, we observe two scenarios: When the phase space is ergodic, both scattering functions are scale invariant with the typical escape time . In contrast, when the phase space is not ergodic, the scattering functions show a clear non-universal and parameter-dependent behavior.