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Title: What determines the rest frame of bubble nucleation?
Abstract We revisit the question addressed in recent papers by Garriga et al.: what determines the rest frame of pair nucleation in a constant electric field? The conclusion reached in these papers is that pairs are observed to nucleate at rest in the rest frame of the detector which is used to detect the pairs. A similar conclusion should apply to bubble nucleation in a false vacuum. This conclusion however is subject to doubt due to the unphysical nature of the model of a constant eternal electric field that was used by Garriga et al. The number density of pairs in such a field would be infinite at any finite time. Here we address the same question in a more realistic model where the electric field is turned on at a finite timet0in the past. The process of turning on the field breaks the Lorentz invariance of the model and could in principle influence the frame of pair nucleation. We find however that the conclusion of Garriga et al. still holds in the limitt0 → -∞. This shows that the setup process of the electric field does not have a lasting effect on the observed rest frame of pair nucleation. On the other hand, the electric current and charge density due to the pairs are determined by the way in which the electric field was turned on.  more » « less
Award ID(s):
2110466
PAR ID:
10563033
Author(s) / Creator(s):
;
Publisher / Repository:
JCAP
Date Published:
Journal Name:
Journal of Cosmology and Astroparticle Physics
Volume:
2023
Issue:
11
ISSN:
1475-7516
Page Range / eLocation ID:
084
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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