The approach of the three interacting fluids applied to the cosmological constant problem

2018/01/23 by Mónica Forte, Forte, Mónica
Earth and Planetary Sciences · Physics and Astronomy · #Cosmology and Gravitation Theories #Earth Systems and Cosmic Evolution #FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc) #Relativity and Gravitational Theory

paper · pdf · doi:10.48550/arxiv.1801.08036

openalex publication_date 2018/01/23 · openalex created_date 2018/02/02 · openalex updated_date 2026/07/28

Abstract

We present a cosmological model constituted by three perfect fluids, cold dark matter, vacuum energy and radiation, which interacting with each other lead to an equivalent model of three self-preserved fluids that can be identified with the ΛCDM model plus a warm dark matter component. The effective energy densities expressed in terms of the global density of energy, its derivatives and interactions, with parameters adjusted with the observational data allow to show the evolution of the vacuum energy. This supports the difference in 120 orders of magnitude of the so-called problem of the cosmological constant and at the same time the strict limits on its density parameter at early times. The best fits parameters of the model, H₀= 74.06 km/sMpc and q₀=-0.78, z_acc=0.75 are concordant with the bibliography and also allow the so-called problems of coincidence and the crisis of age to be alleviated. A geometric analysis performed with statefinders shows the difference with the ΛCDM model because of the evolution of the effective vacuum density of energy.

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