Kinetic field theory for cosmic structure formation

We apply kinetic field theory to non-linear cosmic structure formation. Kinetic decomposes the density into particles and follows their trajectories through phase space. assume that initial particle momenta are drawn from a Gaussian random field. place particular emphasis on late-time, asymptotic behaviour small spatial scales of low-order statistical measures for distribution in configuration velocity Our main result is power spectra fluctuations ensembles freely streaming along Zel'dovich asymptotically fall off with wave number $k$ like $k^{-3}$ $k\to\infty$, irrespective cosmological model type dark matter assumed, exponent set only by dimensions. This conclusion remains valid density-fluctuation if interactions taken account mean-field approximation. also show bispectrum freely-streaming falls $k^{-11/2}$ under same general conditions.