NONCHAOTIC ATTRACTORS WITH HIGHLY FLUCTUATING FINITE-TIME LYAPUNOV EXPONENTS

The implications of large fluctuations of finite-time Lyapunov exponen ts are discussed for nonchaotic systems. We show that for a nonchaotic system driven by quasiperiodic force, if its finite-time Lyapunov exp onents periodically become positive, the resulting attractor can be st range but nonchaotic. With long enough expanding time intervals, a nea rly periodic force can also lead to strange nonchaotic attractors. For the case of a periodic force, a special typical periodic attractor th at is sensitive to micronoise is obtained. With the different finite c omputing precisions, different pseudoperiodic orbits can be obtained.