Browsing by Author "Copeland, E. J."

Now showing items 1-3 of 3

    • Article  

      The dark energy cosmic clock: A new way to parametrise the equation of state 

      Tarrant, E. R. M.; Copeland, E. J.; Padilla, A.; Skordis, C. (2013)
      We propose a new parametrisation of the dark energy equation of state, which uses the dark energy density, Ωe as a cosmic clock. We expand the equation of state in a series of orthogonal polynomials, with Ωe as the expansion ...
    • Article  

      Models of dark matter coupled to dark energy 

      Pourtsidou, A.; Skordis, C.; Copeland, E. J. (2013)
      We present three distinct types of models of dark energy in the form of a scalar field which is explicitly coupled to dark matter. Our construction draws from the pull-back formalism for fluids and generalizes the fluid ...
    • Article  

      Parametrized post-Friedmannian framework for interacting dark energy theories 

      Skordis, C.; Pourtsidou, A.; Copeland, E. J. (2015)
      We present the most general parametrization of models of dark energy in the form of a scalar field which is explicitly coupled to dark matter. We follow and extend the parametrized post-Friedmannian approach, previously ...