Accelerating Cosmologies with an Anisotropic Equation of State

نویسندگان

  • Tomi Koivisto
  • David F. Mota
چکیده

If the dark energy equation of state is anisotropic, the expansion rate of the universe becomes directiondependent at late times. We show that such models are not only cosmologically viable but that they could explain some of the observed anomalies in the CMB. The possible anisotropy can then be constrained by studying its effects on the luminosity distance-redshift relation inferred from several observations. A vector field action for dark energy is also presented as an example of such possibility. Subject headings: (cosmology:) cosmic microwave background; cosmology: miscellaneous; cosmology: observations; cosmology: theory; cosmology: large-scale structure of universe

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تاریخ انتشار 2008