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Reconstructing K-essence

A. A. Sen
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Abstract

We present a model independent method of reconstructing the Lagrangian for the k-essence field driving the present acceleration of the universe. We consider the simplest k-essence model for which the potential is constant. Later we use three parametrizations for the Hubble parameter $H(z)$, consistent with the recent SN1a data, to yield the Lagrangian $F$. Our reconstruction program does not generate any physically realistic Lagrangian for models that allow phantom crossing, whereas models without phantom crossing, yield well behaved Lagrangian.

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A. A. Sen. 2006-02-28. Reconstructing K-essence. https://doi.org/10.1088/1475-7516%2F2006%2F03%2F010

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