http://arxiv.org/abs/1908.08644
Requiring the existence of a unitary, causal and local UV-completion places a set of positivity bounds on the corresponding effective field theories (EFTs). We apply this positivity argument to the EFT of cosmological perturbations. Taking a $c_T=1$ beyond-Horndeski EFT as an illustrative example, we drive such bounds, which naturally incorporate the cosmological correction of order $H^2/\Lambda^2$, in which $\Lambda$ is the cutoff scale. Applications of our results are briefly discussed.
G. Ye and Y. Piao
Mon, 26 Aug 19
42/55
Comments: 20 pages, 2 figures