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arXiv · hep-th/0311180

A First-Quantized Formalism for Cosmological Particle Production

Alex J. Hamilton·Daniel Kabat·Maulik K. Parikh
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Abstract

We show that the amount of particle production in an arbitrary cosmological background can be determined using only the late-time positive-frequency modes. We don't refer to modes at early times, so there is no need for a Bogolubov transformation. We also show that particle production can be extracted from the Feynman propagator in an auxiliary spacetime. This provides a first-quantized formalism for computing particle production which, unlike conventional Bogolubov transformations, may be amenable to a string-theoretic generalization.

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Alex J. Hamilton, Daniel Kabat, Maulik K. Parikh. 2004-05-12. A First-Quantized Formalism for Cosmological Particle Production. https://doi.org/10.1088/1126-6708%2F2004%2F07%2F024

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