3–Ricci curvature. We find that the late–time trajectories of those models approach attractors that lie in the future of a state that is predicted by observational constraints.'
address:
- 'Fakultät für Physik, Universität Bielefeld, Postfach 100131, 33501 Bielefeld, and'
- |
    Arnold Sommerfeld Center for Theoretical Physics ASC, Ludwig–Maximilians–Universität, Theresienstra[ß]{}e 37, 80333 München, Germany\
    Email: buchert@theorie.physik.uni-muenchen.de
- |
    Laboratoire de l’Univers et ses Théories LUTH, CNRS UMR 8102,\
    Observatoire de Paris–Meudon and Université Paris 7, 92195 Meudon, France\
    Emails: Julien.Larena@obspm.fr and Jean-Michel.Alimi@obspm.fr
author:
- Thomas Buchert
- 'Julien Larena and Jean–Michel Alimi'
title: 'Correspondence between kinematical backreaction and scalar field cosmologies — the ‘morphon field’'
---

Introduction
============

The fact that the spatially averaged inhomogeneous Universe does not evolve as the standard model of cosmology, furnished by a homogeneous–isotropic solution of Einstein’s laws of gravity, has recently become a major topic aiming at a possible solution to the Dark Energy problem [@wetterich], [@beanetal:darkenergy], [@straumann]. While the averaging problem in relativistic cosmology has a long history, initiated by George Ellis [@ellis] (references may be found in [@ellisbuchert] and [@buchert:static]), the backreaction terms, i.e. those averaged contributions that lead to deviations from a Friedmannian cosmology, have been considered quantitatively unimportant. Recent work 