Sphalerons and Energy Barriers in the Weinberg-Salam Theory

摘要

Some recent results regarding nontrivial structure in the configuration space ofthe electroweak standard model and related classical solutions (sphalerons) are presented. It is found that the Sphaleron does not change much as the mixing angle is increased from O to pi/6. At very large Higgs mass the Sphaleron acquires more than one negative mode and other solutions ('deformed sphalerons') appear. The reason for this is given. It is concluded that more and more structure in configuration space appears at higher and higher energies and truly nonperturbative understanding (not just saddle point approximations) of Young-Mills-Higgs theory seems to be required.