| Abstract: |
We investigate a range of non-singular cosmological scenarios within the framework of Horndeski gravity. In particular, we construct a bouncing Universe model and propose a minimal setup that realizes a non-pathological Genesis scenario. Both constructions allow for a fully stable transition to the kination epoch, during which General Relativity (GR) is restored. These scenarios successfully evade the no-go theorem, albeit at the expense of potential strong-coupling issues in the early phase. The requirement of strong-coupling avoidance imposes stringent constraints on the model parameters and, in certain cases, forbids the generation of a red-tilted scalar spectrum. Furthermore, we explore an alternative scenario in which the Genesis phase precedes a period of Starobinsky inflation. We show that the corrections from the Genesis phase can naturally account for the recent ACT observations.
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