学术报告

Understanding the nature of Electroweak Symmetry Breaking with CEPC-SPPC

by Prof. Xinmin Zhang (Theory Division, IHEP)

Asia/Shanghai
B324

B324

Description
Understanding the nature of electroweak symmetry breaking is a central issue of the particle physics.The discovery of the Higgs boson at LHC answers part of, but not all of the questions. In this informal talk, I will discuss some of the issues on the nature of electroweak symmetry breaking, such as the Higgs potential and the electroweak phase transition and their implications in particle physics and cosmology. For instance, the strong first order phase transition will be crucial important to solving the problem of missing anti-matter in the universe. In the standard model, the Higgs potential is known and simple. However, with Higgs mass around 125 GeV, it proves the vacuum state is not stable and the phase transition is not strong enough for the electroweak baryogenesis. In this talk I will explain how the new physics beyond the standard model at the TeV scale makes it possible for the strong first order phase transition and baryogenesis. The new physics at the TeV scale will generate the anomalous couplings of the Higgs boson itself and also to the W and Z bosons. This is because the longitudinal parts of these gauge fields form a SU(2) doublet with the Higgs boson. In this talk I will also explain the measurement on the anomalous top quark couplings is also important to understanding the nature of electroweak symmetry breaking. With a model independent analysis and an effective Lagrangian technique, I will argue that the CEPC-SPPC will provide an decisive answer to the issue on the first order phase transition and electroweak baryogenesis, which certainly helps us to understand better the nature of electroweak symmetry breaking.
Poster
Slides