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arXiv · 2312.02492

Cosmological reconstruction and $\Lambda$CDM universe in $f(Q,C)$ gravity

Gaurav N. Gadbail·Avik De·P. K. Sahoo
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Abstract

Symmetric Teleparallel Gravity allows for the reformulation of gravity in the form of nonmetricity by vanishing the contorsion term in the generic affine connection. Our focus is on investigating a recently proposed extension of this theory in which the Lagrangian has the form $f(Q,C)$ by incorporating the boundary term $C$. In this work, we first use a reconstruction approach in $f(Q,C)$ gravity that might admit the $\Lambda$CDM expansion history. Furthermore, we perform a novel approach for cosmological reconstruction of $f(Q,C)$ gravity in terms of e-folding, and it shows how any FLRW cosmology can arise from a specific $f(Q,C)$ gravity. A variety of instances are provided using this approach in which $f(Q, C)$ gravity is reconstructed to yield the well-known cosmic evolution: $\Lambda$CDM era, acceleration/deceleration era which is equivalent to the presence of phantom and non-phantom matter, late-time acceleration with the crossing of phantom-divide line and transient phantom era.

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Gaurav N. Gadbail, Avik De, P. K. Sahoo. 2023-12-05. Cosmological reconstruction and $\Lambda$CDM universe in $f(Q,C)$ gravity. https://doi.org/10.1140/epjc%2Fs10052-023-12288-y

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