Lev Kofman

Reheating after inflation.

The theory of reheating of the Universe after inflation is developed. We have found that typically at the first stage of reheating the classical inflation field

Evolution of one point distributions from Gaussian initial fluctuations

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NONTHERMAL PHASE TRANSITIONS AFTER INFLATION

rapidly decays into

Dynamics of gravitational instability is nonlocal

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Statistics of Gravitational Microlensing Magnification. II. Three-dimensional Lens Distribution

particles or into other bosons due to a broad parametric resonance. Then these bosons decay into other particles, which eventually become thermalized. Complete reheating is possible only in those theories where a single particle

Statistics of cosmological inhomogeneities

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Non-Gaussianity as a Probe of the Physics of the Primordial Universe and the Astrophysics of the Low Redshift Universe

can decay into other particles. This imposes strong constraints on the structure of inflationary models, and implies that the inflation field can be a dark matter candidate.

The Origin of Matter in the Universe: Reheating after Inflation

We study the quasilinear evolution of the one-point probability density functions (PDFs) of the smoothed density and velocity fields in a cosmological gravitating system beginning with Gaussian initial fluctuations. Our analytic results are based on the Zeldovich approximation and laminar flow. A numerical analysis extends the results into the multistreaming regime using the smoothed fields of a CDM N-body simulation. We find that the PDF of velocity, both Lagrangian and Eulerian, remains Gaussian under the laminar Zeldovich approximation, and it is almost indistinguishable from Gaussian in the simulations. The PDF of mass density deviates from a normal distribution early in the quasilinear regime and it develops a shape remarkably similar to a lognormal distribution with one parameter, the rms density fluctuation

Non-Gaussianity as a probe of the physics of the primordial universe and the astrophysics of the low redshift universe

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Cosmic Web: Origin and Observables

. Applying these results to currently available data we find that the PDFs of the velocity and density fields, as recovered by the pot procedure from observed velocities assuming