Disformal couplings and the dark sector of the universe

@article{deBruck2015DisformalCA,
  title={Disformal couplings and the dark sector of the universe},
  author={Carsten van de Bruck and Jack Morrice},
  journal={Journal of Cosmology and Astroparticle Physics},
  year={2015},
  volume={2015},
  pages={036 - 036}
}
Interactions between dark matter and dark energy, allowing both conformal and and disformal couplings, are studied in detail. We discuss the background evolution, anisotropies in the cosmic microwave background and large scale structures. One of our main findings is that a large conformal coupling is not necessarily disallowed in the presence of a general disformal term. On the other hand, we find that negative disformal couplings very often lead to instabilities in the scalar field. Studying… 

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