Sign on

SAO/NASA ADS Astronomy Abstract Service

· Find Similar Abstracts (with default settings below)
· Electronic Refereed Journal Article (HTML)
· arXiv e-print (arXiv:0707.2153)
· References in the article
· Citations to the Article (111) (Citation History)
· Refereed Citations to the Article
· Also-Read Articles (Reads History)
·
· Translate This Page
Title:
Dark Energy from structure: a status report
Authors:
Buchert, Thomas
Affiliation:
AA(Université Lyon 1, Centre de Recherche Astrophysique de Lyon, CNRS UMR 5574; , Laboratoire de l‘Univers et ses Théories LUTh ,CNRS UMR 8102, Observatoire de Paris and Université Paris 7)
Publication:
General Relativity and Gravitation, Volume 40, Issue 2-3, pp. 467-527 (GReGr Homepage)
Publication Date:
02/2008
Origin:
SPRINGER
Keywords:
Relativistic Cosmology, Inhomogeneous Universe Models, Backreaction, Observational Cosmology, Dark Energy
DOI:
10.1007/s10714-007-0554-8
Bibliographic Code:
2008GReGr..40..467B

Abstract

The effective evolution of an inhomogeneous universe model in any theory of gravitation may be described in terms of spatially averaged variables. In Einstein’s theory, restricting attention to scalar variables, this evolution can be modeled by solutions of a set of Friedmann equations for an effective volume scale factor, with matter and backreaction source terms. The latter can be represented by an effective scalar field (“morphon field”) modeling Dark Energy. The present work provides an overview over the Dark Energy debate in connection with the impact of inhomogeneities, and formulates strategies for a comprehensive quantitative evaluation of backreaction effects both in theoretical and observational cosmology. We recall the basic steps of a description of backreaction effects in relativistic cosmology that lead to refurnishing the standard cosmological equations, but also lay down a number of challenges and unresolved issues in connection with their observational interpretation. The present status of this subject is intermediate: we have a good qualitative understanding of backreaction effects pointing to a global instability of the standard model of cosmology; exact solutions and perturbative results modeling this instability lie in the right sector to explain Dark Energy from inhomogeneities. It is fair to say that, even if backreaction effects turn out to be less important than anticipated by some researchers, the concordance high-precision cosmology, the architecture of current N-body simulations, as well as standard perturbative approaches may all fall short in correctly describing the Late Universe.
Bibtex entry for this abstract   Preferred format for this abstract (see Preferences)
   

Find Similar Abstracts:

Use: Authors
Title
Keywords (in text query field)
Abstract Text
Return: Query Results Return    items starting with number
Query Form
Database: Astronomy
Physics
arXiv e-prints