Informal presentation on spin, the little group, and the spinor helicity method

by Andrew Lifson

Tuesday 12 Jan 2021, 11:15 → 12:15 Europe/Stockholm

This informal session will discuss Wigner's quantum mechanics asa basis for understanding what a particle is and how to define its quantum numbers through the little group and measure its spin. After this introduction I will show the basic building blocks of the spinor-helicity formalism, an efficient formalism which has been used in the last 35 years to find remarkably simple expressions for scattering amplitudes. Finally, the link between the two topics will be shown. This informal session is designed 
to be at an introductory level, to be informal (and open to questions and discussions at any time) and somewhat interactive.

Andrew-informal.mp4

spinIntro.pdf