摘要

The recent observational available data for an accelerated expansion state of the present universe, obtained from distant SNeIa gave strong support to the search of alternative cosmologies. Recently, there have been a number of different attempts to modify Einstein's gravity to yield accelerated expansion at late times. Unfortunately, many of the theoretical models discussed in the literature are plagued with theoretical problems, in particular the singularity problem at the origin of time. In the present work we have analyzed a multidimensional spacetime Friedmann-Robertson-Walker (FRW) model with a decaying cosmological constant and a varying gravitational constant. Many interesting consequences are revealed, in particular the behavior of the scale factor and the shape of the universe in terms of the number of extra dimensions.

  • 出版日期2009-11