Probability Distribution Function of Cosmological Density Fluctuations from a Gaussian Initial Condition: Comparison of One-Point and Two-Point Lognormal Model Predictions with N-Body Simulations

  title={Probability Distribution Function of Cosmological Density Fluctuations from a Gaussian Initial Condition: Comparison of One-Point and Two-Point Lognormal Model Predictions with N-Body Simulations},
  author={Issha Kayo and Atsushi Taruya and Yasushi Suto},
  journal={The Astrophysical Journal},
We quantitatively study the probability distribution function (PDF) of cosmological nonlinear density fluctuations from N-body simulations with a Gaussian initial condition. In particular, we examine the validity and limitations of one-point and two-point lognormal PDF models against those directly estimated from the simulations. We find that the one-point lognormal PDF very accurately describes the cosmological density distribution even in the nonlinear regime (rms variance σnl 4, overdensity… Expand

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