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arXiv · 1802.00687

Large-distance behaviour of the massless vector two-point function in de Sitter spacetime

Nicola Rendell
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Abstract

We study the long-distance behaviour of the massless vector propagator in (n)-dimensional de Sitter spacetime, where $n \geq 4$. Specifically, we consider the massless limit of the vector propagator in the Stueckelberg theory, which is an extension of Proca theory, with an additional gauge-fixing term. We work to leading order in the de Sitter-invariant distance $Z$ to show that, in the large $Z$ limit, this propagator tends to a gauge dependent constant, where the gauge worked in is described by the Stueckelberg parameter $ξ$. In the Landau gauge, where $ξ=0$, this constant is found to be 0. This result is in agreement with the 4 dimensional case discussed by Youssef.

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Nicola Rendell. 2018-05-03. Large-distance behaviour of the massless vector two-point function in de Sitter spacetime. https://doi.org/10.1142/s0218271818430058

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