In this work, we consider a braneworld model with a timelike extra dimension. There are strong constraints to the parameter values of such a model resulting from the claim that there must be a physical solution to the Friedmann equation at least between now and the time of recombination. We fitted the model to supernova type Ia data and checked the consistency of the result with other observations. For parameter values that are consistent with observations, the braneworld model is indistinguishable from a $\Lambda \mathrm{CDM}$ universe as far as the considered cosmological tests are concerned.

• Received 14 December 2008

DOI:https://doi.org/10.1103/PhysRevD.79.083531