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Modified Friedmann-Leme\^ıtre equation for dilaton-spin dark matter in Weyl-Cartan space

Olga V. Babourova
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Abstract

It is proposed to consider dark matter as a perfect dilaton-spin fluid (with particles endowed with intrinsic spin and dilaton charge) in the framework of a gravitational theory with a Weyl-Cartan geometrical structure. The modified Friedmann-Lema\^ıtre equation (with a cosmological term) is obtained for the homogeneous and isotropic Universe filled with the dilaton-spin dark matter. On the basis of this equation, we develop a nonsingular cosmological model starting from an inflation-like stage (for super-stiff equation of state), passing radiation-dominated and matter-dominated decelerating stages and turning into a post-Friedmann accelerating era.

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BibTeXRIS

Olga V. Babourova. 2005-07-25. Modified Friedmann-Leme\^ıtre equation for dilaton-spin dark matter in Weyl-Cartan space. https://arxiv.org/abs/gr-qc/0507104

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