Peculiar acceleration

TL;DR

This paper explores the potential to observe peculiar acceleration in nearby galaxies and clusters, which could provide insights into gravitational potentials without virialization assumptions, complementing cosmological redshift measurements.

Contribution

It investigates the feasibility of detecting peculiar acceleration effects in local structures, expanding methods to study gravitational potentials beyond cosmological redshift observations.

Findings

Peculiar acceleration effects are comparable to cosmological velocity shifts.

Potential to reconstruct gravitational potential without virialization assumptions.

Discussion on translating theory into observable quantities.

Abstract

It has been proposed recently to observe the change in cosmological redshift of distant galaxies or quasars with the next generation of large telescope and ultra-stable spectrographs (the so-called Sandage-Loeb test). Here we investigate the possibility of observing the change in peculiar velocity in nearby clusters and galaxies. This ``peculiar acceleration'' could help reconstructing the gravitational potential without assuming virialization. We show that the expected effect is of the same order of magnitude of the cosmological velocity shift. Finally, we discuss how to convert the theoretical predictions into quantities directly related to observations.