Structure in a loitering universe.

Abstract

The authors study the formation of structure for a universe that undergoes a recent loitering phase. They compare the nonlinear mass distribution to that in a standard, matter dominated cosmology. The statistical aspects of the clustered matter are found to be robust to changes in the expansion law, an exception being that the peculiar velocities are lower by a factor of ?3 in the loitering model. Further, in the loitering scenario, nonlinear growth of perturbation occurs more recently (z ? 3 - 5) than in the matter dominated case. Differences in the high redshift appearances of the two models will result but observable consequences depend critically on the chosen form, onset and duration of the loitering phase.