Radiative effects on false vacuum decay in Higgs-Yukawa theory

Ai, Wen-Yuan; Garbrecht, Björn; Millington, Peter

Abstract

We derive fermionic Green’s functions in the background of the Euclidean solitons describing false vacuum decay in a prototypal Higgs-Yukawa theory. In combination with appropriate counterterms for the masses, couplings and wave-function normalization, these can be used to calculate radiative corrections to the soliton solutions and transition rates that fully account for the inhomogeneous background provided by the nucleated bubble. We apply this approach to the archetypal example of transitions between the quasidegenerate vacua of a massive scalar field with a quartic self-interaction. The effect of fermion loops is compared with those from additional scalar fields, and the loop effects accounting for the spacetime inhomogeneity of the tunneling configuration are compared with those where gradients are neglected. We find that scalar loops lead to an enhancement of the decay rate, whereas fermion loops lead to a suppression. These effects get relatively amplified by a perturbatively small factor when gradients are accounted for. In addition, we observe that the radiative corrections to the solitonic field profiles are smoother when the gradients are included. The method presented here for computing fermionic radiative corrections should be applicable beyond the archetypal example of vacuum decay. In particular, we work out methods that are suitable for calculations in the thin-wall limit, as well as others that take account of the full spherical symmetry of the solution. For the latter case, we construct the Green’s functions based on spin hyperspherical harmonics, which are eigenfunctions of the appropriate angular momentum operators that commute with the Dirac operator in the solitonic background.

Citation

Ai, W.-Y., Garbrecht, B., & Millington, P. (2018). Radiative effects on false vacuum decay in Higgs-Yukawa theory. Physical Review D, 98(7), Article 076014. https://doi.org/10.1103/physrevd.98.076014

• Journal Article Type: Article
• Acceptance Date: Sep 25, 2018
• Online Publication Date: Oct 25, 2018
• Publication Date: Oct 25, 2018
• Deposit Date: Oct 26, 2018
• Publicly Available Date: Oct 26, 2018
• Journal: Physical Review D
• Print ISSN: 2470-0010
• Electronic ISSN: 2470-0029
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 98
• Issue: 7
• Article Number: 076014
• DOI: https://doi.org/10.1103/physrevd.98.076014
• Keywords: Physics and Astronomy (miscellaneous)
• Public URL: https://nottingham-repository.worktribe.com/output/1197414
• Publisher URL: https://journals.aps.org/prd/abstract/10.1103/PhysRevD.98.076014
• Contract Date: Oct 26, 2018