Energy Conditions and Segre Classification of Phantom Fields

J. Santos; J. S. Alcaniz

doi:10.1016/j.physletb.2005.05.059

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Energy Conditions and Segre Classification of Phantom Fields

J. Santos·J. S. Alcaniz

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Abstract

Recent discoveries in the field of observational cosmology have provided increasing evidence that the Universe is undergoing a late time acceleration, which has also stimulated speculations on the nature of the dark component responsible for such a phenomenon. Among several candidates discussed in the current literature, phantom fields, an exotic scalar field with a negative kinetic term and that violates most of the classical energy conditions, appear as a real possibility according to recent observational analysis. In this paper we examine the invariant characterization for the energy-momentum tensor of phantom fields through the Segre algebraic classification in the framework of general relativity. We also discuss some constraints which are imposed on the values of $V(ϕ)$ from the classical energy conditions.

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J. Santos, J. S. Alcaniz. 2005-05-24. Energy Conditions and Segre Classification of Phantom Fields. https://doi.org/10.1016/j.physletb.2005.05.059

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