Complexity in cosmic structures

Francesco Sylos Labini; Andrea Gabrielli

doi:10.1016/j.physa.2004.02.022

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arXiv · astro-ph/0401204

Complexity in cosmic structures

Francesco Sylos Labini·Andrea Gabrielli

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Abstract

We discuss correlation properties of a general mass density field introducing a classification of structures based on their complexity. Standard cosmological models for primordial mass fluctuations are characterized by a sort of large-scale stochastic order, that we call super-homogeneity to highlight the fact that mass fluctuations increase as a function of scale in the slowest possible way for any stochastic mass field. On the other hand the galaxy spatial distribution show complex structures with a high degree of inhomogeneity and fractal-like spatial correlations up to some relevant cosmological scale. The theoretical problem of cosmological structure formation should then explain the growth of strongly correlated and non-linear structures from the very uniform field of density fluctuations given as standard initial condition.

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Francesco Sylos Labini, Andrea Gabrielli. 2004-01-12. Complexity in cosmic structures. https://doi.org/10.1016/j.physa.2004.02.022

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