Standard Model Baryon Number Violation at Zero Temperature from Higgs Bubble Collisions
High Energy Physics - Phenomenology
2026-04-27 v2
Abstract
We compute for the first time baryon number violation at zero temperature from Higgs bubble collisions and find that it can be of the same order as that from thermal sphalerons in the symmetric phase at electroweak temperatures. We study the dependence of the rate of Chern--Simons number transitions on the shape of the scalar potential and on the Lorentz factor of the bubble walls at collision via large-scale (3+1)D lattice simulations of the Higgs doublet and SU(2) gauge fields. We estimate the resulting baryon asymmetry assuming some CP-violating source activated by the Higgs-field variation during the phase transition.
Keywords
Cite
@article{arxiv.2508.21825,
title = {Standard Model Baryon Number Violation at Zero Temperature from Higgs Bubble Collisions},
author = {Nabeen Bhusal and Simone Blasi and Martina Cataldi and Aleksandr Chatrchyan and Marco Gorghetto and Geraldine Servant},
journal= {arXiv preprint arXiv:2508.21825},
year = {2026}
}
Comments
See https://www.youtube.com/watch?v=LhZFCxJ5-4g for an animation. Matches version accepted in PRL. 5 pages + appendices