The local effect of Dark Energy in galaxy clusters

TL;DR

This study uses N-body simulations to investigate how Dark Energy influences galaxy outflows in clusters, suggesting a local effect that contributes to the observed Hubble Flow around galaxy clusters.

Contribution

The paper introduces direct N-body simulations to analyze the local impact of Dark Energy on galaxy cluster dynamics and outflows, providing new insights into local cosmological effects.

Findings

Galaxies in the outer regions of clusters exhibit outflows consistent with Dark Energy influence.

Simulations reproduce the local Hubble Flow observed in galaxy clusters.

Evidence suggests Dark Energy has a measurable local effect on galaxy motions.

Abstract

Recently, observational data and high precision mapping of the local velocity field of Local Group and Virgo cluster have revealed a linear velocity-distance relation of the outermost galaxies, properly referred to as Local Hubble Flow. By means of direct N-body method, we performed several simulations in which a galaxy cluster undergoes the action of the Dark Energy force and of the gravitational one induced by the gas. We reproduced the so-called Hubble diagrams, to highlight the outflow of the galaxies lying in the external region of the cluster. Our preliminary results suggest that the observed outflow of galaxies is likely due to the local effect of Dark Energy. Furthermore, the accuracy of the N-body method used, allows us to follow the merging process among some galaxies with the aim to reproduce the formation of a single compact object in the centre of the cluster.