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arXiv · 2601.08917

Cosmological Cutting Rules from Flat-Space Unitarity via Dressing

Arhum Ansari·Sachin Jain·Deep Mazumdar
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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.

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Arhum Ansari, Sachin Jain, Deep Mazumdar. 2026-01-13. Cosmological Cutting Rules from Flat-Space Unitarity via Dressing. https://arxiv.org/abs/2601.08917

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