中国物理学会高能物理分会第十一届全国会员代表大会暨学术年会

We investigate the extent to which perturbative calculations of the electroweak phase transition are arbitrary and uncertain, owing to their gauge, renormalization scale and scheme dependence, as well as treatments of the Goldstone catastrophe and daisy diagrams. Using the complete parameter space of the Standard Model extended by a real scalar singlet with a Z2 symmetry as a test, we explore the properties of the electroweak phase transition in general Rxi and covariant gauges, OS and MSbar renormalization schemes, and common treatments of the Goldstone catastrophe and daisy diagrams. Reassuringly, we find that different renormalization schemes and different treatments of the Goldstone catastrophe and daisy diagrams typically lead to only small changes in predictions for the critical temperature and strength of the phase transition. On the other hand, the gauge and renormalization scale dependence may be significant, and often impact the existence of the phase transition altogether.