GW170817 Viable Einstein-Gauss-Bonnet inflation compatible with the atacama cosmology telescope data
Abstract
In this work we investigate several Einstein-Gauss-Bonnet models that are compatible with the GW170817 event, the Atacama Cosmology Telescope data and the BICEP/Keck updated Planck constraints on the tensor-to-scalar ratio. We consider two distinct classes of Einstein-Gauss-Bonnet theories, which are equally successful for GW170817-compatible model building and we examine their viability against the Atacama Cosmology Telescope data and the updated Planck constraints on the tensor-to-scalar ratio. The two models are distinct since the first class relates directly the non-minimal Gauss-Bonnet scalar coupling function with the scalar potential and yields c T 2 = 1 while in the second class, the non-minimal Gauss-Bonnet scalar coupling function and the scalar potential are freely but conveniently chosen and the class of models respects the constraint | c T 2 − 1 | < 6 × 10 − 15 . We provide several examples of models belonging to both the two classes of GW170817-compatible Einstein-Gauss-Bonnet theories and we demonstrate that Einstein-Gauss-Bonnet theories provide a promising theoretical framework for inflationary dynamics.