Why is the Universe Accelerating?
Astrophysics
2009-07-09 v2 General Relativity and Quantum Cosmology
High Energy Physics - Phenomenology
High Energy Physics - Theory
Abstract
The universe appears to be accelerating, but the reason why is a complete mystery. The simplest explanation, a small vacuum energy (cosmological constant), raises three difficult issues: why the vacuum energy is so small, why it is not quite zero, and why it is comparable to the matter density today. I discuss these mysteries, some of their possible resolutions, and some issues confronting future observations.
Keywords
Cite
@article{arxiv.astro-ph/0310342,
title = {Why is the Universe Accelerating?},
author = {Sean M. Carroll},
journal= {arXiv preprint arXiv:astro-ph/0310342},
year = {2009}
}
Comments
22 pages; Contribution to Measuring and Modeling the Universe, Carnegie Observatories Astrophysics Series Vol. 2, ed. W. L. Freedman; references improved