Lennart Brocki

Cold Inflation versus stochastic inflation

The two dynamical realizations of cosmological inflation are discussed, cold and stochastic inflation. After reviewing the description of the expansion of the Universe and different cosmological models it is explained how inflation solves the flatness and horizon problem. It is shown how the fluctuations of the inflaton lead to scale-invariant density fluctuations. The power spectrum of fluctuations in de Sitter space is calculated for a quantized and for a stochastic scalar field.