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arXiv · 2212.01398

Complex geodesics in de Sitter space

Shira Chapman·Damián A. Galante·Eleanor Harris·Sameer U. Sheorey·David Vegh
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Abstract

The two-point function of a free massive scalar field on a fixed background can be evaluated in the large mass limit by using a semiclassical geodesic approximation. In de Sitter space, however, this poses a puzzle. Certain spacelike separated points are not connected by real geodesics despite the corresponding two-point function in the Bunch-Davies state being non-vanishing. We resolve this puzzle by considering complex geodesics after analytically continuing to the sphere. We compute one-loop corrections to the correlator and discuss the implications of our results to de Sitter holography.

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Shira Chapman, Damián A. Galante, Eleanor Harris, Sameer U. Sheorey, David Vegh. 2022-12-02. Complex geodesics in de Sitter space. https://doi.org/10.1007/jhep03(2023)006

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