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arXiv · 0805.3794

Phantom expansion with non-linear Schr\"{o}dinger-type formulation of scalar field cosmology

Theerakarn Phetnora·Roongtum Sooksan·Burin Gumjudpai
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Abstract

We describe non-flat standard Friedmann cosmology of canonical scalar field with barotropic fluid in form of non-linear Schr\"{o}dinger-type (NLS) formulation in which all cosmological dynamical quantities are expressed in term of Schr\"{o}dinger quantities as similar to those in time-independent quantum mechanics. We assume the expansion to be superfast, i.e. phantom expansion. We report all Schr\"{o}dinger-analogous quantities to scalar field cosmology. Effective equation of state coefficient is analyzed and illustrated. We show that in a non-flat universe, there is no fixed $w_{\rm eff}$ value for the phantom divide. In a non-flat universe, even $w_{\rm eff} > -1$, the expansion can be phantom. Moreover, in open universe, phantom expansion can happen even with $w_{\rm eff} > 0$. We also report scalar field exact solutions within frameworks of the Friedmann formulation and the NLS formulation in non-flat universe cases.

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Theerakarn Phetnora, Roongtum Sooksan, Burin Gumjudpai. 2008-05-24. Phantom expansion with non-linear Schr\"{o}dinger-type formulation of scalar field cosmology. https://doi.org/10.1007/s10714-009-0831-9

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