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arXiv · 1209.2339

Observational constraints on a cosmological model with Lagrange multipliers

Antonella Cid·Pedro Labrana
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Abstract

Cosmological models with Lagrange multipliers are appealing because they could explain the behaviour of the dark sector in a unified way. In this work we analyse extensions to the "Dust of Dark Energy model" proposed in arXiv:1003.5751 by including spatial curvature and more general potentials of the scalar field. We perform dynamical system analysis and we determine the evolution of the equation of state parameter as a function of the scale factor. We present observational constraints on this model by using Union2.1 dataset and H(z) data.

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Antonella Cid, Pedro Labrana. 2012-09-11. Observational constraints on a cosmological model with Lagrange multipliers. https://doi.org/10.1016/j.physletb.2012.09.022

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