  In the brane-world scenario, our universe is understood as a three
dimensional hypersurface embedded in a higher dimensional space-time. The
fluctuations of the brane along the extra dimensions are seen from the
four-dimensional point of view as new fields whose properties are determined by
the geometry of the extra space. We show that such branon fields can be
massive, stable and weakly interacting, and accordinlgy they are natural
candidates to explain the universe missing mass problem. We also consider the
possibility of producing branons non-thermally and their relevance in the
cosmic coincidence problem. Finally we show that some of the branon distinctive
signals could be detected in future colliders and in direct or indirect dark
matter searches.
