Speaker
Cláudio GOMES
Description
We constrain the viable models of Horndeski gravity after the GWs events by resorting to the Witten positive energy theorem. We find that the free function G3(ϕ,X) in the Lagrangian is con- strained to be a function solely of the scalar field, G3(ϕ). In addition,relations among the free functions are found. Other criteria for stability are also analysed, such as the attractiveness of gravity, and the Dolgov-Kawasacki instability. Some applications for cosmology are discussed.
