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arXiv · 1004.1505

Viscous Fluids and Gauss-Bonnet Modified Gravity

Olesya Gorbunova·Lorenzo Sebastiani
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Abstract

We study effects of cosmic fluids on finite-time future singularities in modified $f(R,G)$-gravity, where $R$ and $G$ are the Ricci scalar and the Gauss-Bonnet invariant, respectively. We consider the fluid equation of state in the general form, $\omega=\omega(\rho)$, and we suppose the existence of a bulk viscosity. We investigate quintessence region ($\omega>-1$) and phantom region ($\omega<-1$) and the possibility to change or avoid the singularities in $f(R,G)$-gravity. Finally, we study the inclusion of quantum effects in large curvatures regime.

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Olesya Gorbunova, Lorenzo Sebastiani. 2010-04-09. Viscous Fluids and Gauss-Bonnet Modified Gravity. https://doi.org/10.1007/s10714-010-1031-3

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