title: Chaotic dynamics of the fractional Lorenz system.
abstract: In this Letter we introduce a generalization of the Lorenz dynamical system using fractional derivatives. Thus, the system can have an effective noninteger dimension Sigma defined as a sum of the orders of all involved derivatives. We found that the system with Sigma<3 can exhibit chaotic behavior. A striking finding is that there is a critical value of the effective dimension Sigma(cr), under which the system undergoes a transition from chaotic dynamics to regular one.
authors.affiliation: Institut für Theoretische Physik der Freien Universität Berlin, Arnimallee 14, 14195 Berlin, Germany.
authors.forename: Ilia
authors.initials: I
authors.lastname: Grigorenko
authors.forename: Elena
authors.initials: E
authors.lastname: Grigorenko