Horizon problem and inflation

We show that, the part of the universe that is observable today (in principle), could not have evolved out of a domain which was causally connected in the past. This and other issues related to horizon problem in inflationary models are discussed

Gaussian states in de Sitter spacetime and the evolution of semiclassical density perturbations. 2. Inhomogeneous modes

In the computation of density perturbation in inflation it is conventional to assume the inflation field to be in the vacuum state. There are, however, some advantages in relaxing this assumption. In an earlier paper we have estimated the density perturbations in a Gaussian coherent state using a toy-model. Here we extend this work by doing an exact analysis of this problem. The advantages of this method is discussed and the results are compared with earlier results