Speaker
Description
Throughout the years, various theoretical and experimental findings have challenged the validity of General Relativity at both ultraviolet and infrared scales. In an effort to address some of these shortcomings, extendend gravity models considering modifications of the gravitational action have been proposed. One possible extension involves including the so-called Gauss-Bonnet term in the Lagragian. In doing so, additional geometric contributions can effectively play the role of a cosmological constant, without the need to invoke dark energy models. Among the different possible formulations, the starting action can be selected using the Noether symmetry approach, a physically motivated criterion based on Noether's theorem, aimed at identifying viable models that exhibit symmetries. We demonstrate that applying this approach to a scalar-tensor Gauss Bonnet model allows for a reduction of the dynamical system and the associated minisuperspace, thus enabling the derivation of exact solutions to the equations of motion. In particular, we consider a cosmological context, where the method proves useful in addressing both the early- and late-time accelerated phases of the Universe.
