Cosmological models with the energy density of random fluctuations and the Hubble-constant problem

Kenji Tomita

doi:10.1093/ptep/ptx117

Abstract

First the fluctuation energy is derived from the adiabatic random fluctuations due to the second-order perturbation theory, and the evolutionary relation for it is expressed in the form of rho_f = rho_f (rho), where rho and rho_f are the densities of ordinary dust and the fluctuation energy, respectively. The pressureless matter as a constituent of the universe at the later stage is assumed to consist of ordinary dust and the fluctuation energy. Next, cosmological models including the fluctuation energy as a kind of dark matter are derived using the above relation, and it is found that the Hubble parameter and the other model parameters in the derived models can be consistent with the recent observational values. Moreover, the perturbations of rho and rho_f are studied.

Highlights

At the later stage of the universe, the main constituent is considered to be a pressureless matter consisting of ordinary dust
The fluctuation energy is derived from adiabatic random fluctuations due to second-order perturbation theory, and the evolutionary relation for it is expressed in the form of ρf = ρf (ρ), where ρ and ρf are the densities of ordinary dust and the fluctuation energy, respectively
Cosmological models including the fluctuation energy as a kind of dark matter are derived using the above relation, and it is found that the Hubble parameter and the other model parameters in the derived models can be consistent with the recent observational values

Summary

Kyoto University

Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502, Japan. The fluctuation energy is derived from adiabatic random fluctuations due to second-order perturbation theory, and the evolutionary relation for it is expressed in the form of ρf = ρf (ρ), where ρ and ρf are the densities of ordinary dust and the fluctuation energy, respectively. The pressureless matter as a constituent of the universe at the later stage is assumed to consist of ordinary dust and the fluctuation energy. Cosmological models including the fluctuation energy as a kind of dark matter are derived using the above relation, and it is found that the Hubble parameter and the other model parameters in the derived models can be consistent with the recent observational values. The perturbations of ρ and ρf are studied

Introduction

Evolutionary relation for the fluctuation energy

Cosmological models with the fluctuation energy and the model parameters

Perturbations in cosmological models with the fluctuation energy

At the stage of a