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arXiv · 2306.14912

$f(Q,T)$ gravity: From early to late-time cosmic acceleration

Surajit Das·Sanjay Mandal
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Abstract

In this article, we explore the comprehensive narrative of cosmic evolution within a cosmological framework by utilizing a novel form of gravity known as generalized symmetric teleparallel gravity, denoted as $f(Q,T)$ gravity. Here, $Q$ represents the non-metricity scalar, while $T$ denotes the trace of the energy-momentum tensor. We present and analyze two distinct $f(Q,T)$ cosmological models, each characterized by its unique Lagrangian. Our investigation delves into the cosmological parameters of these models, scrutinizing various energy conditions, examining the inflationary dynamics of the early universe through scalar field formulations, and probing the mysterious nature of dark energy using statefinder diagnostics and $(\omega-\omega')$ phase space analysis. Ultimately, our findings offer a comprehensive account of cosmic evolution, spanning from the early universe to its late-time evolution.

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Surajit Das, Sanjay Mandal. 2023-06-19. $f(Q,T)$ gravity: From early to late-time cosmic acceleration. https://doi.org/10.1007/s12648-024-03400-3

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