Equivalence between the in-in perturbation theories for quantum fields in Minkowski spacetime and in the Rindler wedge

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We investigate the relation between the time-ordered vacuum correlation functions for interacting real scalar fields in Minkowski spacetime and in the Rindler wedge. The correlation functions are constructed perturbatively within the in-in formalism, often employed in calculations in more general spacetimes. We prove to all orders in perturbation theory that the time-ordered vacuum correlation functions can be calculated in the in-in formalism with internal vertices restricted to any Rindler wedge containing the external points. This implies that the Minkowski in-in (or in-out) perturbative expansion of the vacuum correlation functions is reproduced by the Rindler in-in perturbative expansion of these correlators in a thermal state at the Unruh temperature.
Original languageEnglish
Article number065009
Number of pages12
JournalPhysical Review D - Particles, Fields, Gravitation and Cosmology
Publication statusPublished - 17 Mar 2020

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  • Perturbation theory
  • Quantum fields in curved spacetime
  • Unruh effect

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