Cosmological cutting rules from flat-space unitarity via dressing

Abstract

Using cosmological dressing rules, we uplift flat-space unitarity cuts to discontinuity relations for dS/EAdS observables. In this representation, Cutkosky delta functions map directly to “Disc” operations in the exchanged energy variable. This provides a transparent diagram-by-diagram origin of cosmological cutting rules. We illustrate this with explicit examples at tree level and one loop for conformally coupled scalars.