In this work we will review the main properties of brane-world models with
low tension. Starting from very general principles, it is possible to obtain an
effective action for the relevant degrees of freedom at low energies (branons).
Using the cross sections for high-energy processes involving branons, we set
bounds on the different parameters appearing in these models. We also show that
branons provide a WIMP candidate for dark matter in a natural way. We consider
cosmological constraints on its thermal and non-thermal relic abundances. We
derive direct detection limits and compare those limits with the preferred
parameter region in the case in which the EGRET excess in the diffuse galactic
gamma rays is due to dark matter annihilation. Finally we will discuss the
constraints coming from the precision tests of the Standard Model and the muon
anomalous magnetic moment.Comment: 10 pages, 6 figures. Contribution to the Proceedings of the Second
International Conference on Quantum Theories and Renormalization Group in
Gravity and Cosmology, IRGAC 2006, Barcelona, 11-15 July, 200