Year: 2009
Type: article
Abstract: Past and recent data analyses gave some hints of steps in dark energy. Considering dark energy as a dynamical scalar field, we investigate several models with various steps: a step in the scalar potential, a step in the kinetic term, a step in the energy density, and a step in the equation-of-state parameter $w$. These toy models provide a workable mechanism to generate steps and features of dark energy. Remarkably, a single real scalar can cross $w=\ensuremath{-}1$ dynamically with a step in the kinetic term.
Author: Tower Wang
Institution: Peking University
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2020209848