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A critical-density closed Universe in Brans-Dicke theory

S. del Campo·N. Cruz
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Abstract

In a Brans-Dicke (BD) cosmological model, the energy density associated with some scalar field decreases as $\displaystyle a^{{-2}(\frac{ω_{o}+ {\frac12}%}{ω_{o}+1})} $ with the scale factor $a(t)$ of the Universe, giving a matter with an Equation of state $\displaystyle p=-{1/3}(\frac{2+ω_{o}}{1+ω_{o}}) ρ$. In this model, the Universe could be closed but still have a nonrelativistic-matter density corresponding to its critical value, $Ω_{o}=1$. Different cosmological expressions, such as, luminosity distance, angular diameter, number count and ratio of the redshift tickness-angular size, are determined in terms of the redshift for this model.

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S. del Campo, N. Cruz. 2000-04-28. A critical-density closed Universe in Brans-Dicke theory. https://doi.org/10.1046/j.1365-8711.2000.03675.x

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