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Updated: Jul 8, 2026
07:46
Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Standard Model Baryon Number Violation at Zero Temperature from Higgs Bubble Collisions.
Nabeen Bhusal1, Simone Blasi1, Martina Cataldi1,2
1Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany.
Physical Review Letters
|July 7, 2026
Summary
Baryon number violation from Higgs bubble collisions can match thermal sphaleron rates. This study computes this rate for the first time, impacting early universe cosmology and the matter-antimatter asymmetry.
Area of Science:
- Particle Physics
- Cosmology
- Quantum Field Theory
Background:
- The origin of the universe's baryon asymmetry is a major unsolved problem in physics.
- Electroweak phase transitions and associated non-perturbative processes are potential sources of this asymmetry.
Purpose of the Study:
- To compute baryon number violation from Higgs bubble collisions at zero temperature.
- To compare this rate with thermal sphaleron rates in the symmetric phase.
- To investigate the dependence of Chern-Simons number transitions on scalar potential shape and bubble wall Lorentz factor.
Main Methods:
- Large-scale (3+1)D lattice simulations.
- Simulating Higgs doublet and SU(2) gauge fields.
- Estimating baryon asymmetry from CP-violating sources during the phase transition.
Main Results:
- Baryon number violation from Higgs bubble collisions can be of the same order as thermal sphaleron rates.
- The rate of Chern-Simons number transitions depends on the scalar potential and bubble wall dynamics.
Conclusions:
- Higgs bubble collisions provide a significant mechanism for baryon number violation.
- This finding offers a new avenue for explaining the observed baryon asymmetry in the universe.
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