The Nonlinear Evolution of Rare Events
نویسنده
چکیده
In this paper I consider the nonlinear evolution of a rare density fluctuation in a random density field with Gaussian fluctuations, and I rigorously show that it follows the spherical collapse dynamics applied to its mean initial profile. This result is valid for any cosmological model and is independent of the shape of the power spectrum. In the early stages of the dynamics the density contrast of the fluctuation is seen to follow with a good accuracy the form
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تاریخ انتشار 1994