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arXiv · 1807.03724

The quasi-linear nearby Universe

Yehuda Hoffman·Edoardo Carlesi·Daniel Pomarède·Hélène M. Courtois·Stefan Gottlöber·Noam I. Libeskind·Jenny G. Sorce·Gustavo Yepes
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Abstract

The local Universe provides a unique opportunity for testing cosmology and theories of structure formation. To facilitate this opportunity we present a new method for the reconstruction of the quasi-linear matter density and velocity fields from galaxy peculiar velocities and apply it to the Cosmicflows-2 data. The method consists of constructing an ensemble of cosmological simulations, constrained by the standard cosmological model and the observational data. The quasi-linear density field is the geometric mean and variance of the fully non-linear density fields of the simulations. The main nearby clusters (Virgo, Centaurus, Coma), superclusters (Shapley, Perseus-Pisces) and voids (Dipole Repeller) are robustly reconstructed. Galaxies are born biased with respect to the underlying dark matter distribution. Using our quasi-linear framework we demonstrate that the luminosity-weighted density field derived from the 2M++ redshift compilations is non-linearly biased with respect to the matter density field. The bias diminishes in the linear regime.

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Yehuda Hoffman, Edoardo Carlesi, Daniel Pomarède, Hélène M. Courtois, Stefan Gottlöber, Noam I. Libeskind, Jenny G. Sorce, Gustavo Yepes. 2018-07-10. The quasi-linear nearby Universe. https://doi.org/10.1038/s41550-018-0502-4

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