2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/51369It is well known that modifications to the Friedmann equation on a warped brane in an anti de Sitter bulk do not provide any low energy distinguishing feature from standard cosmology. However, addition of a brane curvature scalar in the action produces effects which can serve as a distinctive feature of brane world scenarios and can be tested with observations. The fitting of such a model with supernovae Ia data (including SN 1997ff at $z\approx1.7$) comes out very well and predicts an accelerating universe.5 pages, RevTeX. Revised version. Change in title, 1 figure addedHigh Energy Physics - TheoryAstrophysicsGeneral Relativity and Quantum CosmologyHigh Energy Physics - Phenomenologytext