Cosmology with Ricci dark energy

Sergio Del Campo, Júlio C. Fabris, Ramón Herrera, Winfried Zimdahl

Resultado de la investigación: Contribución a una revistaArtículorevisión exhaustiva

23 Citas (Scopus)

Resumen

We assume the cosmological dark sector to consist of pressureless matter and holographic dark energy with a cutoff length proportional to the Ricci scale. The requirement of separate energy-momentum conservation of the components is shown to establish a relation between the matter fraction and the (necessarily time-dependent) equation-of-state parameter of the dark energy. Focusing on intrinsically adiabatic pressure perturbations of the dark-energy component, the matter perturbations are found as linear combinations of the total energy-density perturbations of the cosmic medium and the relative (nonadiabatic) perturbations of the components. The resulting background dynamics is consistent with observations from supernovae of type Ia, baryonic acoustic oscillations and the differential age of old objects. The perturbation dynamics, on the other hand, is plagued by instabilities which excludes any phantom-type equation of state. The only stable configuration is singled out by a fixed relation between the present matter fraction Ωm0 and the present value ω0 of the equation-of-state parameter of the dark energy. However, this instability-avoiding configuration is only marginally consistent with the observationally preferred background values of the mentioned parameters.

Idioma originalInglés
Número de artículo123002
PublicaciónPhysical Review D - Particles, Fields, Gravitation and Cosmology
Volumen87
N.º12
DOI
EstadoPublicada - 12 jun. 2013
Publicado de forma externa

Huella

Profundice en los temas de investigación de 'Cosmology with Ricci dark energy'. En conjunto forman una huella única.

Citar esto