Particle Physics A Theoretical Overview 2016 07 30

Particle Physics: A Theoretical Overview 杨 金 民 中国科学院理论物理研究所 威海暑期学校（2016. 07. 30)

Outline Introduction to Standard Model New Physics Beyond SM

Lecture 4 Higgs Boson in SM Lecture 5 Some Discussions of SM Lecture 6 Fine-tuning Problem and NP Lecture 7 Custodial Symmetry in SM Lecture 8 Top Quark Lecture 9 Neutrino Oscillation

1. Global Symmetry called global transformation

This is a phase transformation Examples: e. g. , L, B, isospin

rotation phase transformation

2. Local Symmetry

2. 1 Originate from electromagnetic theory

2. 2 Abelian gauge symmetry 变换的先后顺序没关系

invariant under U(1) gauge transformation

In summary not invariant under U(1) gauge transformation 引入规范场和规范导数 invariant under U(1) gauge transformation

U(1) gauge-invariant scalar field theory

2. 3 Non-Abelian gauge symmetry 变换的先后顺序有关系

not invariant under SU(2) gauge transformation 引入规范场和规范导数 invariant under SU(2) gauge transformation

-- note the difference from the SM SU(2)