LOCALIZATION project funded by ANR PRCI gathers a team from Orsay and from Munich to produce the largest constrained simulations of our local Universe. The aim of the project is to search, in the local matter distribution, for an answer to both the σ8 tension and the CMB anomalies observed in the Planck data, by performing a comprehensive analysis of local galaxy clusters and Large-Scale Structure (LSS) and of their impact on the CMB.
Replicas of the local clusters and LSS will be produced in unique state-of-the-art constrained hydrodynamic simulations, namely high fidelity clones of the local Universe within roughly 300 Mpc radius valid down to cluster scales. Thanks to LOCALIZATION’s cluster clones, we will derive for the first time the exact relation between cluster masses and their observed proxies. Thanks to LOCALIZATION’s constrained simulations, we will perform the first exhaustive estimate of the contribution from all possible secondary CMB anisotropies that contribute at the largest angular scales and establish their relation with the observed anomalies in Planck data.