Dynamics of clusters of galaxies in the presence of dark energy: Virgo cluster

TL;DR

The paper investigates how dark energy influences galaxy cluster dynamics, proposing a method to detect radial motions and applying it to Virgo, revealing evidence of cluster expansion linked to galaxy brightness and velocity.

Contribution

It introduces a simple statistical method to identify galaxy radial motions within clusters and applies it to Virgo, providing evidence of cluster expansion due to dark energy effects.

Findings

Galaxies in Virgo subgroups are brighter than in the overall cluster.

A positive correlation exists between galaxy brightness and velocity in subgroups.

Evidence suggests the Virgo cluster is expanding due to dark energy interactions.

Abstract

It is shown that, owing to the interaction of baryonic matter with the carrier of dark energy, all configurations of baryonic matter acquire energy and inevitably must expand. This conclusion applies to all hierarchical levels of the baryonic universe, including galaxy clusters. We propose a simple statistical method for identifying possible radial motions of galaxies within clusters. To illustrate this method, we examined the structural features of the Virgo galaxy cluster and identified its substructure, comprising groups of galaxies of varying multiplicity. Galaxies in the substructure are somewhat brighter than those in the overall cluster, and each subgroup contains an active galaxy. Subgroups are considered to be the product of primordial ejections of matter from the central generator galaxy. It is shown that the average stellar magnitude of galaxies in subgroups positively correlates with their average velocity. This correlation can be interpreted as evidence of cluster expansion.