Structure Formation with Scalar Fields

P. T. P. Viana, A. R. Liddle

Abstract
We discuss structure formation models where a presently evolving scalar field behaves dynamically either as a decaying cosmological constant or as dust. We find that the first case provides a successful alternative to classical cosmological constant models, keeping all the characteristics that have made these some of the most able models in reproducing the available observational data, and with the added possibility of a different recent background evolution for the Universe. We allow the presence of spatial perturbations in the scalar field, and study their effect on the growth of adiabatic energy density perturbations in a cold dark matter component. We consider two alternatives for the scalar field potential: an exponential and that associated with a pseudo-Nambu Goldstone boson.

Astrophysics and Space Science
Volume 261, Page 291
January 1999

DOI: 10.1023/A:1002063708895
ADS Bibliographic code: 1998Ap&SS.261..291V