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arXiv · 1409.4400

Dynamics of Robertson-Walker spacetimes with diffusion

Artur Alho·Simone Calogero·Maria P. Machado Ramos·Ana J. Soares
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Abstract

We study the dynamics of spatially homogeneous and isotropic spacetimes containing a fluid undergoing microscopic velocity diffusion in a cosmological scalar field. After deriving a few exact solutions of the equations, we continue by analyzing the qualitative behavior of general solutions. To this purpose we recast the equations in the form of a two dimensional dynamical system and perform a global analysis of the flow. Among the admissible behaviors, we find solutions that are asymptotically de-Sitter both in the past and future time direction and which undergo accelerated expansion at all times.

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Artur Alho, Simone Calogero, Maria P. Machado Ramos, Ana J. Soares. 2014-09-15. Dynamics of Robertson-Walker spacetimes with diffusion. https://doi.org/10.1016/j.aop.2015.01.010

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