Cosmography of f(R,L,T) gravity

Abstract

In order to explain the accelerated phase of the universe expansion, several alternatives to the standard model have been proposed, such as dark energy models and alternative theories of gravity. Although these approaches rest on different physical aspects, it has been shown that both can be in agreement with data in the current status of cosmological observations, which leads to an enormous degeneration. Therefore, until evidence of higher experimental accuracy is available, more conservative model-independent approaches are useful for breaking this degenerated cosmological models picture. Cosmography as a kinematic study of the Universe is the most popular candidate in this regard. In the present work we develop, as a novelty in the literature, cosmography of the recently proposed $f(R,L,T)$ gravity, for which $f$ is a generic function of the Ricci scalar $R$, the matter Lagrangian density $L$ and the trace of the energy–momentum tensor $T$. We analyze two different cases for the functional form of the $f(R,L,T)$ function. We find the cosmographic parameters for each model and observationally constrain them using cosmic chronometers, baryon acoustic oscillations and gamma-ray bursts. Remarkably, our analysis demonstrates that $f(R,L,T)$ gravity can accommodate the observed cosmic acceleration.