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arXiv · 1011.3755

Infrared behavior and gauge artifacts in de Sitter spacetime: The photon field

Ahmed Youssef
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Abstract

We study the infrared (long distance) behavior of the free photon field in de Sitter spacetime. Using a two-parameter family of gauge fixing terms, we show that the infrared (IR) behavior of the two-point function is highly gauge-dependent and ranges from vanishing to growing. This situation is in disagreement with its counterpart in flat spacetime, where the two-point function vanishes in the IR for any choice of the gauge fixing parameters. A criterion to isolate the "physical" part of the two-point function is given and is shown to lead to a well-behaved two-point function in the IR.

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Ahmed Youssef. 2011-07-14. Infrared behavior and gauge artifacts in de Sitter spacetime: The photon field. https://doi.org/10.1103/physrevlett.107.021101

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