Bianchi type III models with anisotropic dark energy


Akarsu O., Kilinc C. B.

GENERAL RELATIVITY AND GRAVITATION, cilt.42, sa.4, ss.763-775, 2010 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 42 Sayı: 4
  • Basım Tarihi: 2010
  • Doi Numarası: 10.1007/s10714-009-0878-7
  • Dergi Adı: GENERAL RELATIVITY AND GRAVITATION
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.763-775
  • Anahtar Kelimeler: Bianchi type III, Anisotropic fluid, Dark energy, Isotropization, CONSTANT DECELERATION PARAMETER, COSMOLOGICAL MODELS, INFLATIONARY UNIVERSE, VACUUM, FIELD, EXPANSION, FLATNESS, ISOTROPY, HORIZON, MAPS
  • İstanbul Teknik Üniversitesi Adresli: Hayır

Özet

The general form of the anisotropy parameter of the expansion for Bianchi type-III metric is obtained in the presence of a single diagonal imperfect fluid with a dynamically anisotropic equation of state parameter and a dynamical energy density in general relativity. A special law is assumed for the anisotropy of the fluid which reduces the anisotropy parameter of the expansion to a simple form (Delta proportional to H-2V-2, where Delta is the anisotropy parameter, H is the mean Hubble parameter and V is the volume of the universe). The exact solutions of the Einstein field equations, under the assumption on the anisotropy of the fluid, are obtained for exponential and power-law volumetric expansions. The isotropy of the fluid, space and expansion are examined. It is observed that the universe can approach to isotropy monotonically even in the presence of an anisotropic fluid. The anisotropy of the fluid also isotropizes at later times for accelerating models and evolves into the well-known cosmological constant in the model for exponential volumetric expansion.