Perturbations of the Quintom Models of Dark Energy and the Effects on Observations

By Gong-Bo Zhao, J. Xia, Mingzhe Li, Bo Feng, Xinmin Zhang. 2005

214 citations recorded by the source corpus.

We study in this paper the perturbations of the quintom dark energy model and the effects of quintom perturbations on the current observations. Quintom describes a scenario of dark energy where the equation of state gets across the cosmological constant boundary w = -1 during evolution. We present a new method to show that the conventional dark energy models based on a single k-essence field and perfect fluid cannot act as the quintom due to the singularities and classical instabilities of perturbations around w= -1. One needs to add extra degrees of freedom for successful quintom model building. There are no singularities or classical instabilities in perturbations of realistic quintom models and they are potentially distinguishable from the cosmological constant. Basing on the realistic quintom models in this paper we provide one way to include the perturbations for dark energy models with parametrized equation of state across -1. Compared with those assuming no dark energy perturbations, we find that the parameter space which allows the equation of state to get across -1 will be enlarged, in general, when including the perturbations.

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/46e871b59f163e1389f66f036b8f9a2db1582c87

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Citations in the corpus

Imperfect Dark Energy from Kinetic Gravity Braiding (2010, result): “At this point, we note that since the action contains second derivatives, therefore possibility of smoothly crossing of the wX = −1 barrier does not contradict the statement proved in [55] and rederived in different ways later in [75, 76, 77, 78, 79, 80, 50].”
SEVEN-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE (WMAP) OBSERVATIONS: COSMOLOGICAL INTERPRETATION (2010, methodology): “In Section 5.5 of Komatsu et al. (2009a), we provided a “WMAP normalization prior,” which is a constraint 32 Zhao et al. (2005) used a multi-scalar-field model to treat w crossing −1.”
A kinematical approach to dark energy studies (2006, background): “…‘phantom’ dark energy models, violate the dominant energy condition (Carroll et al. 2003; Onemli & Woodard 2004) and present serious problems relating to the treatment of dark energy perturbations (Hu 2005; Vikman 2005; Caldwell & Doran 2005; Zhao et al. 2005) when w(z) crosses the boundary w = −1.”
The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: tomographic BAO analysis of DR12 combined sample in Fourier space (2016, background): “We pay particular attention to the DE perturbations when w(a) crosses the −1 boundary (Zhao et al. 2005; Fang, Hu & Lewis 2008).”
Dust of dark energy (2010, result): “[42] G.”
The clustering of galaxies in the SDSS‐III Baryon Oscillation Spectroscopic Survey: cosmological implications of the large‐scale two‐point correlation function (2012, methodology): “Alternatively, as proposed by Zhao et al. (2005), it is possible to consider the dark energy perturbations using a two-field model, with one of the fields being quintessence-like and the other one phantom-like (e.g. the quintom model proposed in Feng et al. 2005) without introducing new internal…”