Abstract
In this paper, we investigate possible solutions to the coincidence problem in flat phantom dark-energy models with a constant dark-energy equation of state and quintessence models with a linear scalar field potential. These models are representative of a broader class of cosmological scenarios in which the universe has a finite lifetime. We show that, in the absence of anthropic constraints, including a prior probability for the models inversely proportional to the total lifetime of the universe excludes models very close to the cold dark matter model. This relates a cosmological solution to the coincidence problem with a dynamical dark-energy component having an equation-of-state parameter not too close to at the present time. We further show that anthropic constraints, if they are sufficiently stringent, may solve the coincidence problem without the need for dynamical dark energy.
- Received 11 March 2011
DOI:https://doi.org/10.1103/PhysRevD.83.103001
© 2011 American Physical Society