%0 Journal Article %T Dynamical Instabilities of the Randall-Sundrum Model %A Timon Boehm %A Ruth Durrer %A Carsten van de Bruck %J Physics %D 2001 %I arXiv %R 10.1103/PhysRevD.64.063504 %X We derive dynamical equations to describe a single 3-brane containing fluid matter and a scalar field coupling to the dilaton and the gravitational field in a five dimensional bulk. First, we show that a scalar field or an arbitrary fluid on the brane cannot evolve to cancel the cosmological constant in the bulk. Then we show that the Randall-Sundrum model is unstable under small deviations from the fine-tuning between the brane tension and the bulk cosmological constant and even under homogeneous gravitational perturbations. Implications for brane world cosmologies are discussed. %U http://arxiv.org/abs/hep-th/0102144v2