Precision constrained simulation of the Local Universe

TL;DR

This paper presents a highly precise simulation of the Local Universe using constrained Gaussian random fields, matching observed galaxy distributions and velocities, and demonstrating the method's effectiveness for local cosmic studies.

Contribution

The authors develop a constrained simulation method based on reconstructed velocities, achieving high correlation with observed data and providing a new tool for local universe analysis.

Findings

Correlation of 0.97 between simulated and observed log-density fields

Good agreement between simulated and observed velocity fields

Two-point correlation functions match well for galaxies and dark matter

Abstract

We use the formalism of constrained Gaussian random field to compute a precise large scale simulation of the 60 Mpc/h volume of our Local Universe. We derive the constraints from the reconstructed peculiar velocities of the 2MASS Redshift Survey. We obtain a correlation of 0.97 between the log-density field of the dark matter distribution of the simulation and the log-density of observed galaxies of the Local Universe. We achieve a good comparison of the simulated velocity field to the observed velocity field obtained from the galaxy distances of the NBG-3k. At the end, we compare the two-point correlation function of both the 2MRS galaxies and of the dark matter particles of the simulation. We conclude that this method is a very promising technique of exploring the dynamics and the particularities the Universe in our neighbourhood.