Inflation for Large Scale Structure

Abstract

Two extensions of ideas lying in the basis of the inflationary scenario of the early Universe and their effect on the large scale structure of the present-day Universe are discussed. The first of them is the possibility of fast phase transitions in physical fields other than an inflaton scalar field during inflation and nor far from the end of it. This results in the appearance of specific features in the inflaton effective potential which, in turn, lead to the generation of localized spikes in the primordial perturbation spectrum. At present, there seems to exist one scale in the spectrum, $k=0.05h$ Mpc$^{-1}$, around which we might see something of this type. The second one is the possibility that we are living at the beginning of a new inflation-like era now. Then observations of clustering of high-redshift objects can provide information sufficient for the unambiguous determination of the effective potential of a corresponding present inflaton scalar field.