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Natural Phantom Dark Energy, Wiggling Hubble Parameter $H(z)$ and Direct $H(z)$ Data

Hongsheng Zhang·Zong-Hong Zhu
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Abstract

Recent direct $H(z)$ data indicate that the parameter $H(z)$ may wiggle with respect to $z$. On the other hand the luminosity distance data of supernovae flatten the wiggles of $H(z)$ because of integration effect. It is expected that the fitting results can be very different in a model permitting a wiggling $H(z)$ because the data of supernovae is highly degenerated to such a model. As an example the natural phantom dark energy is investigated in this paper. The dynamical property of this model is studied. The model is fitted by the direct $H(z)$ data set and the SNLS data set, respectively. And the results are quite different, as expected. The quantum stability of this model is also shortly discussed. We find it is a viable model if we treat it as an effective theory truncated by an upperbound.

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Hongsheng Zhang, Zong-Hong Zhu. 2008-05-13. Natural Phantom Dark Energy, Wiggling Hubble Parameter $H(z)$ and Direct $H(z)$ Data. https://doi.org/10.1088/1475-7516%2F2008%2F03%2F007

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