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arXiv · 1309.4787

ORIGAMI: Delineating Cosmic Structures with Phase-Space Folds

Mark C. Neyrinck·Bridget L. Falck·Alex S. Szalay
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Abstract

Structures like galaxies and filaments of galaxies in the Universe come about from the origami-like folding of an initially flat three-dimensional manifold in 6D phase space. The ORIGAMI method identifies these structures in a cosmological simulation, delineating the structures according to their outer folds. Structure identification is a crucial step in comparing cosmological simulations to observed maps of the Universe. The ORIGAMI definition is objective, dynamical and geometric: filament, wall and void particles are classified according to the number of orthogonal axes along which dark-matter streams have crossed. Here, we briefly review these ideas, and speculate on how ORIGAMI might be useful to find cosmic voids.

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Mark C. Neyrinck, Bridget L. Falck, Alex S. Szalay. 2013-09-18. ORIGAMI: Delineating Cosmic Structures with Phase-Space Folds. https://doi.org/10.1142/9789814623995_0378

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