ar X iv : g r - qc / 0 40 50 38 v 1 7 M ay 2 00 4 SO ( 1 , 1 ) dark energy model and the universe transition ∗
نویسندگان
چکیده
We suggest a scalar model of dark energy with the SO(1, 1) symmetry. The model may be reformulated in terms of a real scalar field Φ and the scale factor a so that the Lagrangian may be decomposed as that of the real quintessence model plus the negative coupling energy term of Φ to a. The existence of the coupling term Lc leads to a wider range of wΦ and overcomes the problem of negative kinetic energy in the phantom universe model. We propose a power-law expansion model of univese with time-dependent power, which can describe the phantom universe and the universe transition from ordinary acceleration to super acceleration.
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