Vacuum bubble collisions: From microphysics to gravitational waves

Gould, Oliver; Sukuvaara, Satumaaria; Weir, David

Abstract

We comprehensively study the effects of bubble wall thickness and speed on the gravitational wave emission spectrum of collisions of two vacuum bubbles. We numerically simulate a large dynamical range, making use of symmetry to reduce the dimensionality. The high-frequency slope of the gravitational wave spectrum is shown to depend on the thickness of the bubble wall, becoming steeper for thick-wall bubbles, in agreement with recent fully 3+1 dimensional lattice simulations of many-bubble collisions. This dependence is present, even for highly relativistic bubble wall collisions. We use the reduced dimensionality as an opportunity to investigate dynamical phenomena which may underlie the observed differences in the gravitational wave spectra. These phenomena include “trapping,” which occurs most for thin-wall bubbles, and oscillations behind the bubble wall, which occur for thick-wall bubbles.

Citation

Gould, O., Sukuvaara, S., & Weir, D. (2021). Vacuum bubble collisions: From microphysics to gravitational waves. Physical Review D, 104(7), Article 075039. https://doi.org/10.1103/physrevd.104.075039

• Journal Article Type: Article
• Acceptance Date: Sep 28, 2021
• Online Publication Date: Oct 28, 2021
• Publication Date: Oct 28, 2021
• Deposit Date: Jan 13, 2022
• Publicly Available Date: Feb 9, 2022
• Journal: Physical Review D
• Print ISSN: 2470-0010
• Electronic ISSN: 2470-0029
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 104
• Issue: 7
• Article Number: 075039
• DOI: https://doi.org/10.1103/physrevd.104.075039
• Public URL: https://nottingham-repository.worktribe.com/output/6187476
• Publisher URL: https://journals.aps.org/prd/abstract/10.1103/PhysRevD.104.075039