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 for a wide range of subjects: 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, focusing 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.

Short bio: After bachelor degrees on physics/astronomy and ?mathematics from Peking University, I got a PhD on theoretical physics ?from Peking University in 2009, and worked as postdoc at ?Albert-Einstein Institute (2009-2012), joint postdoc at Perimeter ?Institute and Member at Institute for Advanced Study (2012-2015). In ?Sep 2015, I jointed Institute of Theoretical Physics, CAS as an ?Associate Professor. My research area is theoretical high-energy ?physics, especially on fundamental questions in Quantum Field Theory, ?String Theory and Quantum Gravity. In the past decade, I have been ?mostly working on scattering amplitudes in QFT and related topics in ?gauge/gravity duality.