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String Dilaton Fluid Cosmology

S. Capozziello·G. Lambiase·R. Capaldo
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Abstract

We investigate $(n+1)$-dimensional string-dilaton cosmology with effective dilaton potential in presence of perfect-fluid matter.We get exact solutions parametrized by the constant $\gam$ of the state equation $p=(\gam-1)ρ$, the spatial dimension number $n$, the bulk of matter, and the spatial curvature constant $k$. Several interesting cosmological behaviours are selected. Finally we discuss the recovering of ordinary Einstein gravity starting from string dominated regime and a sort of asymptotic freedom due to string effective coupling.

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S. Capozziello, G. Lambiase, R. Capaldo. 1998-05-13. String Dilaton Fluid Cosmology. https://doi.org/10.1142/s0218271899000183

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