Cosmological acceleration from energy influx

We discuss the cosmological evolution of a 3-brane universe in the presence of energy influx from the bulk. We show that this influx can lead to accelerated expansion on the brane, depending on the equations of state of the bulk and brane matter. The absorption of non-relativistic bulk matter by the brane at an increasing rate leads to a small positive acceleration parameter during the era of matter domination on the brane. On the other hand, the brane expansion remains decelerating during radiation domination. (C) 2003 Published by Elsevier B.V.