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arXiv · 0906.2085

Proposal for the origin of the cosmological constant

R. Dale·J. A. Morales-Lladosa·D. Saez
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Abstract

We work in the framework of a simple vector-tensor theory. The parametrized post-Newtonian approximation of this theory is identical to that of general relativity. Our attention is focused on cosmology. In an homogeneous isotropic universe, it is proved that the energy density, $ρ_{A}$, of the vector field $A$, and its pressure, $p_{A}$, do not depend on time, and also that the equation of state is $ρ_{A} = -p_{A}$. This means that, in the theory under consideration, there is a cosmological constant, which is not vacuum energy, but the dark energy of the cosmic vector field $A$, whose evolution is classical.

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R. Dale, J. A. Morales-Lladosa, D. Saez. 2009-08-20. Proposal for the origin of the cosmological constant. https://arxiv.org/abs/0906.2085

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