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On the dynamics of the universe in $D$ spatial dimensions

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 Added by Rodrigo Holanda
 Publication date 2012
  fields Physics
and research's language is English




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In this paper we present the equations of the evolution of the universe in $D$ spatial dimensions, as a generalization of the work of Lima citep{lima}. We discuss the Friedmann-Robertson-Walker cosmological equations in $D$ spatial dimensions for a simple fluid with equation of state $p=omega_{D}rho$. It is possible to reduce the multidimensional equations to the equation of a point particle system subject to a linear force. This force can be expressed as an oscillator equation, anti-oscillator or a free particle equation, depending on the $k$ parameter of the spatial curvature. An interesting result is the independence on the dimension $D$ in a de Sitter evolution. We also stress the generality of this procedure with a cosmological $Lambda$ term. A more interesting result is that the reduction of the dimensionality leads naturally to an accelerated expansion of the scale factor in the plane case.



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