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arXiv · 2304.02300

How different connections in flat FLRW geometry impact energy conditions in $f(Q)$ theory?

Ganesh Subramaniam·Avik De·Tee-How Loo·Yong Kheng Goh
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Abstract

In this study of the modified $f(Q)$ theory of gravity in the spatially flat Friedmann-Lema\^itre-Robertson-Walker (FLRW) spacetime, we explore all the affine connections compatible with the symmetric teleparallel structure; three classes of such connections exist, each involving an unknown time-varying parameter $\gamma(t)$. Assuming ordinary barotropic fluid as the matter source, we first derive the Friedmann-like pressure and energy equations. Next we impose constraints on the parameters of two separate $f(Q)$ models, $f(Q)=Q+\beta Q^2$ and $f(Q)=Q+\beta\sqrt{-Q}$ from the traditional energy conditions. Observational values of some prominent cosmological parameters are used for this purpose, yielding an effective equation of state $\omega^{eff}=-0.82$.

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Ganesh Subramaniam, Avik De, Tee-How Loo, Yong Kheng Goh. 2023-04-05. How different connections in flat FLRW geometry impact energy conditions in $f(Q)$ theory?. https://doi.org/10.1002/prop.202300038

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