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arXiv · hep-th/0309098

Relationship between (2+1) and 3+1)--Friedmann--Robertson--Walker cosmologies

A. Garcia·M. Cataldo·S. del Campo
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Abstract

In this work we establish the correspondence between solutions to the Friedmann--Robertson--Walker cosmologies for perfect fluid and scalar field sources, where both ones fulfill state equations of the form $p+ρ=γf(ρ)$, not necessarily linear ones. Such state equations are of common use in the case of matter--fluids, nevertheless, for a scalar field, they introduce relationships on the potential and kinetic scalar field energies which restrict the set of solutions. A theorem on this respect is demonstrated: From any given (3+1)--cosmological solution, obeying the quoted state equations, one can derive its (2+1)--cosmological counterpart or vice-versa. Some applications are given.

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A. Garcia, M. Cataldo, S. del Campo. 2003-09-09. Relationship between (2+1) and 3+1)--Friedmann--Robertson--Walker cosmologies. https://doi.org/10.1103/physrevd.68.124022

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