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arXiv · 1301.3311

Canonical and phantom scalar fields as an interaction of two perfect fluids

Mauricio Cataldo·Fabiola Arevalo·Patricio Mella
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Abstract

In this article we investigate and develop specific aspects of Friedmann-Robertson-Walker (FRW) scalar field cosmologies related to the interpretation that canonical and phantom scalar field sources may be interpreted as cosmological configurations with a mixture of two interacting barotropic perfect fluids: a matter component $ρ_1(t)$ with a stiff equation of state ($p_1=ρ_1$), and an "effective vacuum energy" $ρ_2(t)$ with a cosmological constant equation of state ($p_2=-ρ_2$). An important characteristic of this alternative equivalent formulation in the framework of interacting cosmologies is that it gives, by choosing a suitable form of the interacting term $Q$, an approach for obtaining exact and numerical solutions. The choice of $Q$ merely determines a specific scalar field with its potential, thus allowing to generate closed, open and flat FRW scalar field cosmologies.

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Mauricio Cataldo, Fabiola Arevalo, Patricio Mella. 2013-01-15. Canonical and phantom scalar fields as an interaction of two perfect fluids. https://doi.org/10.1007/s10509-012-1346-5

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