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arXiv · 1906.01058

Spinor-helicity variables for cosmological horizons in de Sitter space

Adrian David·Nico Fischer·Yasha Neiman
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Abstract

We consider massless fields of arbitrary spin in de Sitter space. We introduce a spinor-helicity formalism, which encodes the field data on a cosmological horizon. These variables reduce the free S-matrix in an observer's causal patch, i.e. the evolution of free fields from one horizon to another, to a simple Fourier transform. We show how this result arises via twistor theory, by decomposing the horizon<->horizon problem into a pair of (more symmetric) horizon<->twistor problems.

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Adrian David, Nico Fischer, Yasha Neiman. 2019-06-03. Spinor-helicity variables for cosmological horizons in de Sitter space. https://doi.org/10.1103/physrevd.100.045005

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