Approaches to understanding cosmic acceleration
Abstract
Theoretical approaches to explaining the observed acceleration of the universe are reviewed. We briefly discuss the evidence for cosmic acceleration, and the implications for standard general relativity coupled to conventional sources of energy-momentum. We then address three broad methods of addressing an accelerating universe: the introduction of a cosmological constant, its problems and origins; the possibility of dark energy and the associated challenges for fundamental physics and the option that an infrared modification of general relativity may be responsible for the large-scale behavior of the universe.
- Publication:
-
Reports on Progress in Physics
- Pub Date:
- September 2009
- DOI:
- 10.1088/0034-4885/72/9/096901
- arXiv:
- arXiv:0904.0024
- Bibcode:
- 2009RPPh...72i6901S
- Keywords:
-
- Astrophysics - Cosmology and Extragalactic Astrophysics;
- General Relativity and Quantum Cosmology;
- High Energy Physics - Phenomenology;
- High Energy Physics - Theory
- E-Print:
- Invited review article for Reports on Progress in Physics, 55 pages, 7 figures. References added, numerous minor edits. Accepted for publication in Reports on Progress in Physics