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arXiv · 2108.04234

An accelerated universe with negative equation of state parameter in Inhomogeneous Cosmology with $k$-essence scalar field

Somnath Mukherjee·Debashis Gangopadhyay
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Abstract

We obtain a scaling relation for spherically symmetric k-essence scalar fields $\phi(r,t)$ for an inhomogeneous cosmology with the Lemaitre-Tolman- Bondi (LTB) metric. We show that this scaling relation reduces to the known relation for a homogeneous cosmology when the LTB metric reduces to the Friedmann-Lemaitre-Robertson-Walker (FLRW) metric under certain identifications of the metric functions. A k-essence lagrangian is set up and the Euler-Lagrangian equations solved assuming $\phi(r,t)=\phi_{1}(r) + \phi_{2}(t)$. The solutions enable the LBT metric functions to be related to the fields. The LTB inhomogeneous universe exhibits accelerated expansion i.e.cosmic acceleration driven by negative pressure.

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Somnath Mukherjee, Debashis Gangopadhyay. 2021-08-08. An accelerated universe with negative equation of state parameter in Inhomogeneous Cosmology with $k$-essence scalar field. https://arxiv.org/abs/2108.04234

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