Thawing quintessence with a nearly flat potential

By R. Scherrer, A. A. Sen. 2007

176 citations recorded by the source corpus.

The thawing quintessence model with a nearly flat potential provides a natural mechanism to produce an equation of state parameter, w, close to -1 today. We examine the behavior of such models for the case in which the potential satisfies the slow-roll conditions: [(1/V)(dV/d{phi})]{sup 2}<<1 and (1/V)(d{sup 2}V/d{phi}{sup 2})<<1, and we derive the analog of the slow-roll approximation for the case in which both matter and a scalar field contribute to the density. We show that in this limit, all such models converge to a unique relation between 1+w, {omega}{sub {phi}}, and the initial value of (1/V)(dV/d{phi}). We derive this relation and use it to determine the corresponding expression for w(a), which depends only on the presentday values for w and {omega}{sub {phi}}. For a variety of potentials, our limiting expression for w(a) is typically accurate to within {delta}w < or approx. 0.005 for w<-0.9. For redshift z < or approx. 1, w(a) is well fit by the Chevallier-Polarski-Linder parametrization, in which w(a) is a linear function of a.

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/8f1a618b189dd95cdede23fda6605037d2cafa9c

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

In Nuclear and High Energy Physics

Citations in the corpus

Cosmology and Fundamental Physics with the Euclid Satellite (2012, background): “1), [356] parametrize the case of slow-rolling fields, [1050] study thawing quintessence, [602] and [310] include non-minimally coupled fields, [1077] quintom quintessence, [439] parametrize hilltop quintessence, [309] extend the quintessence parametrization to a class of k-essence models, [616] stu”
Assessing observational constraints on dark energy (2024, unknown): “The models we consider, sometimes referred to as “thawing dark energy” [14], have the property that w ( z ) → − 1 at early times (large z ) because Hubble friction during the matter-and radiation-dominated eras is large enough to freeze the scalar field.”