Dynamical reconstruction of the $\Lambda$CDM model in scalar-tensor $f(R,T)$ gravity

Understand

In this work, we use the dynamical system approach to explore the cosmological background evolution of the scalar-tensor representation of $f(R,T)$ gravity, where $R$ is the Ricci scalar and $T$ is the trace of the stress-energy tensor.

• The motivation for this work resides in finding dynamical cosmological behaviors comparable with the $\Lambda$CDM model without the necessity of recurring to a dark energy component.
• We introduce a set of dynamical variables that allow for a direct comparison with the cosmological standard model and the current experimental measurements, and develop a dynamical system framework to analyze the cosmological evolution of Friedmann-Lema\^itre-Robertson-Walker (FLRW) universes within this theory.
• In this framework, we obtain the critical points in the cosmological phase space and perform fully numerical integrations of the dynamical system to extract the cosmological behavior, subjected to initial conditions compatible with the measurements by the Planck satellite.