Multidimensional Cosmology with Anisotropic Fluid: Acceleration and Variation of G

نویسنده

  • J.-M. Alimi
چکیده

A multidimensional cosmological model describing the dynamics of n+1 Ricci-flat factor-spaces Mi in the presence of a one-component anisotropic fluid is considered. The pressures in all spaces are proportional to the density: pi = wiρ , i = 0, ..., n . Solutions with accelerated expansion of our 3-space M0 and small enough variation of the gravitational constant G are found. These solutions exist for two branches of the parameter w0 . The first branch describes superstiff matter with w0 > 1, the second one may contain phantom matter with w0 < −1, e.g., when G grows with time.

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تاریخ انتشار 2006