Reconstructing quintom from WMAP 5-year observations: Generalized ghost condensate

TL;DR

This paper reconstructs a quintom dark energy model using WMAP 5-year data, demonstrating how a generalized ghost condensate scalar field can realize the crossing of the cosmological constant boundary, and compares it with other models.

Contribution

It introduces a reconstruction of the quintom dark energy model from observational data using the generalized ghost condensate framework, highlighting its effectiveness and comparing with other dark energy parametrizations.

Findings

The generalized ghost condensate model can realize the crossing of w=-1.

Reconstruction from WMAP data supports the viability of the quintom scenario.

Comparison shows differences between models based on data fitting.

Abstract

In the 5-year WMAP data analysis, a new parametrization form for dark energy equation-of-state was used, and it has been shown that the equation-of-state, $w(z)$, crosses the cosmological-constant boundary $w=-1$. Based on this observation, in this paper, we investigate the reconstruction of quintom dark energy model. As a single-real-scalar-field model of dark energy, the generalized ghost condensate model provides us with a successful mechanism for realizing the quintom-like behavior. Therefore, we reconstruct this scalar-field quintom dark energy model from the WMAP 5-year observational results. As a comparison, we also discuss the quintom reconstruction based on other specific dark energy ansatzs, such as the CPL parametrization and the holographic dark energy scenarios.