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arXiv · 1201.1448

The correspondence between a scalar field and an effective perfect fluid

Valerio Faraoni
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Abstract

It is widely acknowledged that, for formal purposes, a minimally coupled scalar field is equivalent to an effective perfect fluid with equation of state determined by the scalar potential. This correspondence is not complete because the Lagrangian densities P and -rho, which are equivalent for a perfect fluid, are not equivalent for a minimally coupled scalar field. The exchange between these two Lagrangian densities amounts to exchanging a canonical scalar field with a phantom scalar field.

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Valerio Faraoni. 2012-01-06. The correspondence between a scalar field and an effective perfect fluid. https://doi.org/10.1103/physrevd.85.024040

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