Event

Cosmological correlators is a young field while its sibling, scattering amplitudes, has been studied thoroughly. We consider the implication of non-linearly realized symmetries in cosmology for correlation functions, which is a set of soft theorems analogous to that in scattering amplitude. We introduce the physical mode condition in order for the soft theorems to apply on equal time correlation functions. A set of identities is derived for the quasi-single field scenario and they can be employed to constraint correlation functions. In the second part, we will discuss the possible implication of unitarity on cosmological correlators and challenges to the program of bringing ideas from scattering amplitude to cosmological correlators.