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arXiv · 2301.08876

Reconstruction of $f(Q,T)$ Lagrangian for various cosmological scenario

Gaurav N. Gadbail·Simran Arora·P. K. Sahoo
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Abstract

The variety of theories that can account for the dark energy phenomenon encourages current research to concentrate on a more in-depth examination of the potential impacts of modified gravity on both local and cosmic scales. We discuss some cosmological reconstruction in $f(Q,T)$ cosmology (where $Q$ is the non-metricity scalar, and $T$ is the trace of the energy-momentum tensor) corresponding to the evolution background in Friedmann-La\^imatre-Robertson-Walker (FLRW) universe. This helps us to determine how any FLRW cosmology can arise from a specific $f(Q,T)$ theory. We use the reconstruction technique to derive explicit forms of $f(Q,T)$ Lagrangian for the different kinds of matter sources and Einstein's static universe. We also formulate the models using several ansatz forms of the $f(Q,T)$ function for $p=\omega \rho$. We demonstrate that several classes of $f(Q,T)$ theories admit the power-law and de-Sitter solutions in some ranges of $\omega$. Additionally, we reconstruct the cosmological model for the scalar field with a specific form of $f(Q,T)$. These new models with cosmological inspiration may impact gravitational phenomena at other cosmological scales.

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Gaurav N. Gadbail, Simran Arora, P. K. Sahoo. 2023-01-21. Reconstruction of $f(Q,T)$ Lagrangian for various cosmological scenario. https://doi.org/10.1016/j.physletb.2023.137710

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