Rodrigo R. Cuzinatto , Rajendra P. Gupta , Pedro J. Pompeia
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引用次数: 0
Abstract
In this paper we consider a double-scalar-field extension to scalar–tensor theories of gravity. Our theory is based in the metric tensor and two scalar fields. We keep the idea in Brans–Dicke theory that the gravitational coupling is an effective phenomenon from the dynamics of a scalar field . In addition to that, we raise the speed of light to the status of an independent scalar field. The dynamical analysis of and is performed in the phase space and the conditions for the existence of stable equilibrium points are determined. These conditions accommodate the constraint in accordance with the ansatz that has recently received support from astrophysical and cosmological phenomenology. We analyze this possibility in the context of FLRW cosmology and a chameleon-like mechanism we dubbed -meleon. We obtain specific solutions for the -meleon field, including (i) an O’Hanlon and Tupper-like solution, (ii) dust-matter plus the varying (and ), and (iii) vacuum energy plus the varying (and ).
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