Dynamics and constraints of the dissipative Liouville cosmology

TL;DR

This paper explores a dissipative Liouville cosmology with dilaton dark energy, testing its compatibility with recent cosmological data and its potential to be distinguished from LambdaCDM through structure formation and cluster surveys.

Contribution

It introduces and tests a new Liouville dark energy model against observational data, demonstrating its viability and potential observational signatures.

Findings

Liouville models fit supernova and BAO data well

Growth rates in Liouville models align with observations

Predicted halo distributions differ from LambdaCDM, enabling observational tests

Abstract

In this article we investigate the properties of the FLRW flat cosmological models in which the cosmic expansion of the Universe is affected by a dilaton dark energy (Liouville scenario). In particular, we perform a detailed study of these models in the light of the latest cosmological data, which serves to illustrate the phenomenological viability of the new dark energy paradigm as a serious alternative to the traditional scalar field approaches. By performing a joint likelihood analysis of the recent supernovae type Ia data (SNIa), the differential ages of passively evolving galaxies, and the Baryonic Acoustic Oscillations (BAOs) traced by the Sloan Digital Sky Survey (SDSS), we put tight constraints on the main cosmological parameters. Furthermore, we study the linear matter fluctuation field of the above Liouville cosmological models. In this framework, we compare the observed growth rate of clustering measured with those predicted by the current Liouville models. Performing a chi^2 statistical test we show that the Liouville cosmological model provides growth rates that match sufficiently well with the observed growth rate. To further test the viability of the models under study, we use the Press-Schechter formalism to derive their expected redshift distribution of cluster-size halos that will be provided by future X-ray and Sunyaev-Zeldovich cluster surveys. We find that the Hubble flow differences between the Liouville and the LambdaCDM models provide a significantly different halo redshift distribution, suggesting that the models can be observationally distinguished.