Multicanonical sampling of rare trajectories in chaotic dynamical systems

In chaotic dynamical systems a number of rare trajectories with low level of chaoticity are embedded in chaotic sea while extraordinary unstable trajectories can exist even in weakly chaotic regions In this study a quantitative method for searching these rare trajectories is developed the method is based on multicanonical Monte Carlo and can estimate the probability of initial conditions that lead to trajectory fragments of a given level of chaoticity The proposed method is successfully tested with four-dimensional coupled standard maps where probabilities as small as 10(-14) are estimated (C) 2010 Elsevier BV All rights reserved