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arXiv · astro-ph/0203435

Asymptotic behavior of a stratified perturbation in a three dimensional expanding Universe

D. Fanelli·E. Aurell
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Abstract

The non-linear evolution of a stratified perturbation in a three dimensional expanding Universe is considered. A general Lagrangian scheme (Q model) is introduced and numerical investigations are performed. The asymptotic contraction of the core of the agglomeration is studied. A power-law scaling is detected and an heuristic interpretation of the numerical findings is provided. An asymptotic equation for the multi-stream velocity flow is derived and it is shown to agree quantitatively with the dynamics of the Q model. The relation to the adhesion model is discussed.

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D. Fanelli, E. Aurell. 2002-03-25. Asymptotic behavior of a stratified perturbation in a three dimensional expanding Universe. https://doi.org/10.1051/0004-6361%3A20021197

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