Analysis of Large Scale Structure using Percolation, Genus and Shape Statistics (original) (raw)
1999, Proceedings of the International Astronomical Union
We study a class of FRW space-times with a non-minimally coupled scalar field. We find exact solutions of the Klein-Gordon equation and show that negative values of the coupling parameter xi, lead to more long range power in the two point function and in the vacuum expectation value of the energy-momentum tensor tmn. This fundamentally affects Inflationary particle production of massless non-minimal scalars since the dominant contribution to comes from Hubble-scale modes. As a result the energy density of created scalar particles exceeds that of conventional matter at late times, leading to Omegam < 1 and a `coasting' expansion rate a propto t. Thus Inflation can generically predict Omegam < 1 while retaining a flat geometry if the vacuum contains contributions from massless non-minimal scalar fields. This might provide a resolution to the `Omega problem' for low density cosmological models.
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