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arXiv · 1411.1268

The Peak/Dip Picture of the Cosmic Web

Graziano Rossi
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Abstract

The initial shear field plays a central role in the formation of large-scale structures, and in shaping the geometry, morphology, and topology of the cosmic web. We discuss a recent theoretical framework for the shear tensor, termed the `peak/dip picture', which accounts for the fact that halos/voids may form from local extrema of the density field - rather than from random spatial positions; the standard Doroshkevich's formalism is generalized, to include correlations between the density Hessian and shear field at special points in space around which halos/voids may form. We then present the `peak/dip excursion-set-based' algorithm, along with its most recent applications - merging peaks theory with the standard excursion set approach.

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Graziano Rossi. 2014-11-05. The Peak/Dip Picture of the Cosmic Web. https://arxiv.org/abs/1411.1268

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