Cosmological Models Separable in Non-comoving Coordinates

نویسنده

  • José M. M. Senovilla
چکیده

We study new separable orthogonally transitive abelian G2 on S2 models with two mutually orthogonal integrable Killing vector fields. For this purpose we consider separability of the metric functions in a coordinate system in which the velocity vector field of the perfect fluid does not take its canonical form, providing thereby solutions which are non-separable in comoving coordinates in general. Some interesting general features concerning this class of solutions are given. We provide a full classification for these models and present several families of explicit solutions with their properties.

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تاریخ انتشار 1998