| عنوان مجله
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INTERNATIONAL JOURNAL OF THEORETICAL PHYSICS
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| چکیده
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Regarding the Veneziano ghost of QCD and its generalized form, we consider
a Friedmann-Robertson-Walker (FRW) universe filled by a pressureless matter and a dark
energy component interacting with each other through a mutual sign-changeable interaction
of positive coupling constant. Our study shows that, at the late time, for the deceleration
parameter we have q → −1, while the equation of state parameter of the interacting ghost
dark energy (GDE) does not cross the phantom line, namely ωD ≥ −1. We also extend our
study to the generalized ghost dark energy (GGDE) model and show that, at late time, the
equation of state parameter of the interacting GGDE also respects the phantom line in both
flat and non-flat universes. Moreover, we find out that, unlike the non-flat universe, we have
q →−1 at late time for flat FRWuniverse. In order to make the behavior of the underlying
models more clear, the deceleration parameter q as well as the equation of state parameter
wD for flat and closed universes have been plotted against the redshift parameter, z. All of
the studied cases admit a transition in the expansion history of universe from a deceleration
phase to an accelerated one around z ≈ 0.6.
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