Cosmic slowing down of acceleration using $f_{gas}$

TL;DR

This paper uses recent $f_{gas}$ measurements to analyze the universe's expansion, suggesting that cosmic acceleration may have peaked and is now slowing down, confirmed by independent data sets.

Contribution

It demonstrates the potential of $f_{gas}$ data as an independent probe to detect the slowing down of cosmic acceleration, revisiting previous findings with new observational evidence.

Findings

Evidence of cosmic acceleration peaking and slowing down.

Independent confirmation using $f_{gas}$ data.

Supports previous results with new data sets.

Abstract

We investigate the recent - low redshift - expansion history of the universe using the most recent observational data. Using only data from 42 measurements of $f_{gas}$ in clusters, we found that cosmic acceleration could have already peaked and we are witnessing now its slowing down. This effect, found previously by Shafieloo, Sahni and Starobinsky in 2010 using supernova data (at that time the Constitution SNIa sample) appears again using an independent observational probe. We also discuss the result using the most recent Union 2.1 data set.