Quantum (informatic) probes for quasi-de Sitter backgrounds

de Sitter space is often encountered in cosmology. In this
talk, I will treat QFT in a quasi-de Sitter background, e.g., inflation,
as an open quantum system and derive, in a systematic manner, quantum
corrections to cosmological observables due to interactions with
unobservable environments. For instance, the "cosmological horizon" is
an example of a spacetime boundary that restricts our observable degrees
of freedom while still allowing energy and information to flow across it
into hidden sectors. Borrowing techniques from Quantum Information
Theory, I will show how an Open Effective Field Theory formalism can
incorporate non-unitary effects in cosmology which capture dissipation
(and decoherence) of primordial fields. On the other hand, different
inflationary backgrounds (such as slow-roll, ultra slow roll etc) have
hidden symmetries which are revealed by quantum informatic tools.