Dark energy with polytropic equation of state

نویسندگان

  • Utpal Mukhopadhyay
  • Saibal Ray
چکیده

Equation of state parameter plays a significant role for guessing the real nature of dark energy. In the present paper polytropic equation of state p = ωρn is chosen for some of the kinematical Λ-models viz., Λ ∼ (ȧ/a), Λ ∼ ä/a and Λ ∼ ρ. Although in dust cases (ω = 0) closed form solutions show no dependency on the polytropic index n, but in non-dust situations some new possibilities are opened up including phantom energy with supernegative (ω < −1) equation of state parameter.

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تاریخ انتشار 2005