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Universal Behavior of Phase Correlations in Non-linear Gravitational Clustering

Peter Watts·Peter Coles·Adrian Melott
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Abstract

The large-scale structure of the Universe is thought to evolve by a process of gravitational amplification from low-amplitude Gaussian noise generated in the early Universe. The later, non-linear stages of gravitation-induced clustering produce phase correlations with well-defined statistical properties. In particular, the distribution of phase differences $D$ between neighboring Fourier modes provides useful insights into the clustering phenomenon. Here we develop an approximate theory for the probability distribution $D$ and test it using a large battery of numerical simulations. We find a remarkable universal form for the distribution which is well described by theoretical arguments.

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Peter Watts, Peter Coles, Adrian Melott. 2003-04-22. Universal Behavior of Phase Correlations in Non-linear Gravitational Clustering. https://doi.org/10.1086/376351

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