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arXiv · 2112.09284

Vacuum decay in the Lorentzian path integral

Takumi Hayashi·Kohei Kamada·Naritaka Oshita·Jun'ichi Yokoyama
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Abstract

We apply the Lorentzian path integral to the decay of a false vacuum and estimate the false-vacuum decay rate. To make the Lorentzian path integral convergent, the deformation of an integral contour is performed by following the Picard-Lefschetz theory. We show that the nucleation rate of a critical bubble, for which the corresponding bounce action is extremized, has the same exponent as the Euclidean approach. We also extend our computation to the nucleation of a bubble larger or smaller than the critical one to which the Euclidean formalism is not applicable.

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Takumi Hayashi, Kohei Kamada, Naritaka Oshita, Jun'ichi Yokoyama. 2021-12-17. Vacuum decay in the Lorentzian path integral. https://doi.org/10.1088/1475-7516/2022/05/041

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