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arXiv · 2310.19865

Finite-Temperature Instantons from First Principles

Thomas Steingasser·Morgane König·David I. Kaiser
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Abstract

We derive the finite-temperature quantum-tunneling rate from first principles. The rate depends on both real- and imaginary-time; we demonstrate that the relevant instantons should therefore be defined on a Schwinger-Keldysh contour, and how the familiar Euclidean-time result arises from it in the limit of large physical times. We generalize previous results for general initial states, and identify distinct behavior in the high- and low-temperature limits, incorporating effects from background fields. We construct a consistent perturbative scheme that incorporates large finite-temperature effects.

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Thomas Steingasser, Morgane König, David I. Kaiser. 2023-10-30. Finite-Temperature Instantons from First Principles. https://doi.org/10.1103/physrevd.110.l111902

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