PERIOD-DOUBLING OF A TORUS IN A CHAIN OF OSCILLATORS

We have experimentally studied the transition to chaos in a quasi-one- dimensional chain of nonlinear coupled oscillators, with periodic boun dary conditions. We show that as long as the dynamics are not chaotic, this transition follows an unusual scenario: the period doubling of a T2 torus. During this scenario all oscillators remain in phase. When the chain of oscillators bifurcates to chaos, it loses its spatial hom ogeneity and localized wave holes randomly propagate along the chain.