The serendipity of electroweak baryogenesis

Area of Science:

• Particle Physics
• Cosmology

Background:

• The Standard Model (SM) of particle physics does not explain the universe's matter-antimatter asymmetry or its flavour structure.
• Electroweak (EW) baryogenesis is a theoretical framework to explain this asymmetry.

Purpose of the Study:

• To explore a novel approach linking the origin of flavour structure to CP violation for EW baryogenesis.
• To investigate if varying Yukawa couplings during Higgs field evolution can generate the observed baryon asymmetry.

Main Methods:

• Investigating the role of time-varying Yukawa couplings during the Higgs mechanism.
• Analyzing CP violation sourced from fermion Yukawa couplings during electroweak symmetry breaking.
• Calculating the baryon asymmetry for different Yukawa coupling variation scenarios.

Main Results:

• Yukawa couplings varying with the Higgs field can serve as a source of CP violation for EW baryogenesis.
• This approach bypasses stringent constraints from electric dipole moment experiments.
• The computed baryon asymmetry naturally achieves the observed cosmic abundance.

Conclusions:

• A connection between flavour physics and EW baryogenesis is established through time-varying Yukawa couplings.
• This framework offers new possibilities for explaining the matter-antimatter asymmetry within extensions of the Standard Model.
• Models like Randall-Sundrum or Composite Higgs provide a motivated context for these ideas.