报告题目：New Structures and Formulations for S-matrices
报告人：何颂 副研究员 （中国科学院理论物理研究所）
In the past decades and especially the last one, powerful new tools and remarkable new structures for perturbative scattering amplitudes in QFT have been discovered. Apart from playing a prominent role in high-energy particle physics, these developments have important implications in a wide range: from string perturbation theory to multi-loop calculations in (super)-gravity, from new mathematics to all-loop amplitudes in N=4 SYM. I will review some recent progress, with focus on two topics: (1) a string-inspired new formulation for amplitudes in gauge theories and gravity, and double-copy between them (2) new geometric structures underlying amplitudes which may hint at a "theory at infinity" for S-matrices.